JPH07244167A - Optical detection device and vehicle applying said device - Google Patents

Abstract

PURPOSE:To precisely detect a mark even when an optical face has been contaminated and to prevent a malfunction when a traffic lane is detected by a method wherein beams of reflected light from different light receiving regions on the surface of an object are received separately by at least three photodetectors and the mark or the like on the surface of the object is detected. CONSTITUTION:Light projecting elements 10 to 12 are turned on. Respective beams of reflected light are received by photodetectors 14 to 16, they are amplified 21 to 23, and they are then demodulated 24 to 26. Then, a DC signal from the demodulation circuit 24 and a threshold value which is set by a threshold-value generation circuit 13 are compared 29. When the DC signal is larger than the threshold value, 0 is output, and, when the DC signal is smaller, 1 is output. A DC signal from the circuit 26 and the threshold value are compared 30. When the DC signal is larger than the threshold value, 0 is output, and, when the DC signal is smaller, 1 is output. When outputs of the comparators 29, 30 are both 1, the output of an AND gate 31 is 1, and a CPU 32 operates an R alarm 33 so as to inform that a vehicle has come too much to the right side. On the other hand, an optical detection device 110 operates an L alarm 34. In this manner, only when a white line comes in the field of view of the photodetector 15 in the center, the white line is detected, an inessential region is eliminated, and a malfunction is prevented.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical detection device for projecting light onto an object surface such as a road for a vehicle or a road for an unmanned vehicle, and detecting a reflected light to detect a mark or the like on the surface of the object. The present invention relates to a vehicle to which the device is applied.

[0002]

2. Description of the Related Art Conventionally, as an optical object detecting device, there is a photoelectric switch used in a factory line or the like. Usually, this photoelectric switch has only a detection object as a light receiving field (light receiving area), The presence or absence of the object is detected based on the result of comparison between the absolute amount of light received by the light receiving element and the reference value. Further, as a device that contributes to the prevention of drowsiness of a driver of a vehicle, there is, for example, one disclosed in Japanese Patent Laid-Open No. 271411/1992. , Give a warning. That is, it has two light-receiving fields arranged in parallel, and it is determined whether the road surface is a white line or a white line based on the difference in brightness between the light-receiving fields, and a warning is given when the shift from the road surface to the white line is detected. In this case, when the two light-receiving fields of view are both dark, it is determined to be a road surface, and when one of the light-receiving fields of view is bright and the other light-receiving field of view is dark, it is determined to be a white line.

[0003]

However, such a conventional optical object detecting device has the following problems. (B) When the optical surface of a photoelectric switch becomes dirty, the absolute amount of received light may change, which may prevent accurate presence / absence detection. In an easy environment, it was not practical in terms of reliability. (B) Even in the device of the above-mentioned publication which detects the white line, the lane marking line of the white line or the yellow line and the road surface are determined by the difference in brightness between the two light-receiving fields. However, there is a risk that accurate determination cannot be made, and high reliability in an environment susceptible to contamination cannot be obtained. (C) Further, the device of the above-mentioned publication has a problem in that a malfunction occurs or a dead zone occurs on a split road surface having a boundary where one side is concrete and the other side is asphalt. That is, as shown in FIG. 7B, when both the visual fields 2A and 2B are at the positions intermediate between the white line 1 and the road surface 3, the light and shade are the same. I will end up. This position is the dead zone. The occurrence of this dead zone may miss the warning opportunity for the driver, and is not preferable due to the characteristics of the device. On the other hand, on the split road surface, when the visual field 2A is on a dark road surface (asphalt) and the visual field 2B is on a bright road surface (concrete) as shown in FIG.
Even if it is not, the white line 1 is determined, and a useless warning is given to the driver. (D) In either the photoelectric switch or the device of the above publication, the object surface having a reflectance different from the reference value is simply present in the detection region, or the boundary between the object surfaces having a relatively different reflectance. Can be detected only in the detection area, and by detecting where in the detection area the portion (or boundary) with different reflectance is located,
It was not possible to make detailed judgments about the presence of marks and the like on the surface of an object and notify them in stages.

Therefore, according to the present invention, it is possible to optically finely determine the existence state of marks and the like on the surface of an object.
Provided are an optical detection device capable of accurately detecting marks even when the optical surface is dirty, and having no dead zone in applications such as lane detection on a road surface and causing less malfunction, and a vehicle to which the device is applied. Is intended.

[0005]

In order to achieve the above object, an optical detecting device according to a first aspect of the present invention comprises a light projecting means for irradiating a surface of an object with light, and the light projected by the light projecting means. The light receiving means comprises at least three light receiving elements for receiving the reflected light on the object surface, and each of these light receiving elements is configured to separately receive the reflected light from different light receiving areas on the object surface, and the light receiving means. A detection unit that detects a detected portion such as a predetermined mark formed on the surface of the object based on the outputs of at least three light receiving elements.

According to a second aspect of the present invention, in the optical detecting device, the light receiving means is set such that at least the width between the outer edges of the light receiving regions on both outermost sides is larger than the width of the detected portion.

According to another aspect of the optical detecting device of the present invention, the detecting means compares the outputs of at least three light receiving elements,
It is characterized in that the detected part is detected based on their relative outputs. The optical detection device according to claim 4,
The object surface is a road surface, and the detected portion is a road surface display.

According to another aspect of the optical detecting device of the present invention, the light projecting means includes a light projecting element and a uniformizing means for reducing a deviation of a light amount distribution of light from the light projecting element between the light receiving regions. It is characterized by having. An optical detecting device according to a sixth aspect is characterized in that the light projecting means includes a plurality of light projecting elements.

An optical detection device according to a seventh aspect is characterized in that the light receiving means includes one light receiving lens common to each light receiving element. 9. The optical detection device according to claim 8, wherein one light projecting / receiving lens common to the light projecting means and the light receiving means is provided, and the light projecting means irradiates the object surface with light through the light projecting / light receiving lens. In addition, the light receiving means is configured to receive the reflected light from the surface of the object through the light projecting / receiving lens.

An optical detecting device according to a ninth aspect is characterized in that the light projecting means and the light receiving means are provided with polarizing elements whose transmission polarization planes are orthogonal to each other. A vehicle according to claim 10 is a vehicle equipped with the optical detection device according to any one of claims 1 to 9 for detecting a road surface display, and is based on detection of the road surface display by the optical detection device. It is characterized in that it is provided with an informing means for informing the driver of the vehicle that the road surface display has been detected.

The vehicle according to claim 11 is characterized in that the notifying means makes a stepwise notification based on detection of a road surface display by the optical detection device.

A vehicle according to claim 12 is a vehicle equipped with the optical detection device according to any one of claims 1 to 9 for detecting a road surface display, wherein the road surface display is detected by the optical detection device. On the basis of the above, a steering angle control means for controlling the steering angle of the wheels is provided.

According to a thirteenth aspect of the present invention, the optical detection device is attached to at least left and right side portions of the vehicle, respectively, and based on the outputs of at least these two optical detection devices, the informing means or the steering angle control. It is characterized in that the means is configured to notify or control the steering angle. The vehicle according to claim 14, wherein the optical detection device is
At least one of the light receiving areas is positioned outside the vehicle. Claim 15
The vehicle described above is characterized in that the respective light receiving regions in the optical detection device are positioned so as to be arranged obliquely with respect to the traveling direction of the vehicle.

[0014]

According to the first aspect of the present invention, the detected portion formed on the object surface is detected based on the outputs of at least three light receiving elements that separately receive the reflected light from different light receiving regions on the object surface. Therefore, it is possible to optically and finely determine the existence state of the mark or the like on the surface of the object by the light receiving regions of three or more places. For example, even when detecting a high reflection band such as a white line on the road surface, the white line or the like may be detected depending on which of the three or more light receiving elements has a larger amount of received light than a reference value (threshold). It is also possible to determine whether it is on the center side or the end side in the entire area where the light receiving area of is arranged.

According to the second aspect of the present invention, the width between the outer edges of the light receiving areas on both outermost sides, that is, the width of the detection area is set larger than the width of the detected portion to be detected. Therefore, the dead zone does not occur on the white line on the road,
Further, it is possible to surely detect the split road surface without misidentifying it. That is, in this case, the entire width of the high reflection band such as a white line can be positioned inside the detection region, and in this state, only the amount of light received for the light receiving regions on both ends is naturally small. At the same time, the amount of received light is less than the reference value, and the amount of received light in the central light receiving area is greater than or equal to the reference value (that is,
(When the full width of the high reflection band is located inside the detection area)
In addition, by determining that the white line or the like exists, the presence of the white line or the like can be reliably detected. In other words, if there are three or more light-receiving areas, and the width of the detection area that these light-receiving areas extend is larger than the width of the detected area, the edges of the detected area (the boundaries where the intensity of reflected light changes) are on both sides. Both can be recognized at the same time, and the existence, the current position, etc. can be determined after determining the width of the detected portion to some extent and determining that the detected portion is the predetermined detected portion. Also, when the detected part or part of it is present in the detection area, any light-receiving area or part of it is protruding from the detected part. The amount of light received by the device is not always uniform. Therefore, by comparing the amount of light received by each light-receiving element, a white line or the like on the road surface (a portion where the reflectance is locally different) is detected. Even if it is determined to be the surface), the insensitive body as in the conventional case does not occur.

According to the third aspect of the invention, the predetermined detected portion is detected based on the relative output of each light receiving element, that is, by comparing the amount of light received by each light receiving element. Therefore,
Compared with the case where the detected portion is determined by comparing the received light amount with an absolute reference value, malfunction does not easily occur even if there is dirt on the optical surface of the device side or dirt on the object surface side. This is because if the surface of the object is uniformly soiled, the relative value of the amount of received light in each light receiving region does not change even if the absolute value of the amount of received light changes.

According to the fourth aspect of the invention, the detected portion is displayed on the road surface. Therefore, it is possible to finely detect the presence status of the road surface display (for example, the proximity status to the vehicle). According to the fifth aspect of the invention, the homogenizing means reduces the deviation of the light amount distribution of the light from the light projecting means between the light receiving regions. Therefore, for example, even if the optical surface of the light projecting element is partially contaminated, the decrease in the amount of light due to this contamination is uniform in each light receiving region, and thus erroneous detection due to dirt is unlikely to occur. Further, since a plurality of light projecting elements are provided, and even if there are variations in the amount of light emitted from these light projecting elements, the variations are also uniform in each light receiving region, so that erroneous detection due to this variation does not occur.

According to a sixth aspect of the invention, the light projecting means is composed of a plurality of light projecting elements. Therefore, the light amount of the light projecting means is increased to relatively reduce the influence of external light (sunlight, light of indoor lighting, light of external light, etc.), and the occurrence of malfunction due to external light can be easily reduced. According to the invention of claim 7,
One light receiving lens common to each light receiving element is provided. Therefore, even if the lens surface becomes dirty, the decrease in brightness due to this dirt becomes uniform in each light-receiving area, and erroneous detection due to this dirt hardly occurs.

According to an eighth aspect of the invention, one light projecting / receiving lens is provided in common for the light projecting means and the light receiving means. Therefore, it is possible to reduce the cost, and
It is possible to reduce the dependency of the detection characteristic on the distance variation between the device and the surface of the object to be detected. In the invention according to claim 9, the light projecting means and the light receiving means are provided with polarizing elements whose transmission polarization planes are orthogonal to each other. Therefore, when a high reflection band such as a white line is detected as the predetermined detected portion, it is possible to reliably distinguish the high reflection band formed of a mirror surface such as a puddle or a glass surface and perform a detection operation without malfunction. That is, in a white line or the like, light is diffusely reflected and the direction of polarization changes variously.
Even when such polarizing elements that are orthogonal to each other are provided, the reflected light sufficiently reaches the light receiving means and is detected. However, in the case of a mirror surface, the irradiation light uniformly polarized by the polarizing element on the light projecting means side. Is directly specularly reflected, so that the polarization direction is perpendicular to the polarization element on the light receiving / receiving stage side, and the light is blocked by this polarization element.

According to the tenth aspect of the invention, the optical detection device of the present invention is mounted on a vehicle, and the road surface display is detected by the driver of the vehicle based on the detection of the road surface display by the optical detection device. A notifying means for notifying the user is provided. Therefore, it is possible to inform the driver that the road surface display is at a predetermined position with respect to the vehicle and call various cautions. For example, if the central separation lane (white line or the like), which is a type of road surface display, is detected, the driver can be warned to prevent the driver from driving to the opposite lane due to drowsiness or the like. According to the invention of claim 11, the notifying means performs stepwise notification based on detection of road surface display by the optical detection device. Therefore, for example, the driver is warned step by step while changing the mode from a weak one to a strong one according to the degree of approach to the vehicle such as a lane, and the driver is not unnecessarily anxious. You can According to a twelfth aspect of the present invention, the optical detection device of the present invention is mounted on a vehicle, and the steering angle control means for controlling the steering angle of the wheels is provided based on the detection of the road surface display by the optical detection device. Therefore, for example, by causing the vehicle to travel along the lane, it becomes possible to autonomously drive the vehicle.

According to the thirteenth aspect of the present invention, the optical detecting device is attached to at least both left and right sides of the vehicle. Therefore, the notification function by the notification means or the self-sustained running function by the steering angle control means can be performed more finely and with higher accuracy. For example, in the notification function, a stop line or the like in a direction perpendicular to the traveling direction can be detected separately from the lane along the traveling direction, and in the self-sustained traveling function, for example, along the lanes provided on both sides of the vehicle track It becomes possible to run a fixed orbit accurately. In the invention according to claim 14, at least one light receiving area among the respective light receiving areas is positioned outside the vehicle. Therefore, the notification function by the notification means or the self-sustained travel function by the steering angle control means can be performed more finely and with higher accuracy. That is,
The warning function can detect the lane, etc. before the vehicle gets on the lane, etc., and warn that the vehicle is approaching the lane, etc. It is possible to detect early that the vehicle is about to deviate from the above and to control the steering angle to an appropriate steering angle earlier, and it is possible to prevent meandering and the like. According to the fifteenth aspect of the present invention, the respective light receiving regions in the optical detection device are positioned so as to be arranged obliquely with respect to the vehicle traveling direction. Therefore, even in the notification function or the self-sustaining traveling function, the detected parts (lanes, stop lines, etc.) in various directions can be detected step by step without omission, and safer and smoother traveling of the vehicle can be realized. That is, if the light receiving area is arranged diagonally,
Whether it is a detected part extending in a direction parallel to the vehicle traveling direction (for example, a center separation line) or a detected part extending in a direction (lateral direction) perpendicular to the vehicle traveling direction (for example, a stop line) , The degree of approach of these various detected parts to the vehicle (approach in the advancing direction and the lateral direction) is determined by determining which of the three or more light receiving elements has a larger amount of received light than a reference value (threshold value). Position) can be detected.

[0022]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below with reference to the drawings. Example 1. FIG. 1 is a block diagram showing the configuration of a white line detecting device to which the first embodiment of the optical detecting device according to the present invention is applied. This white line detection device detects a white line or a yellow line on a road. In the figure, reference numerals 10, 11, and 12 denote light emitting elements such as light emitting diodes, lamps, and semiconductor lasers, which are arranged in parallel in a direction perpendicular to the traveling direction of a vehicle (not shown) at regular intervals. It is attached to the right end of the front part of a vehicle (not shown) such that the light projecting direction can be freely adjusted within a range of 180 degrees. A light projecting lens (convex lens) 13A is arranged in front of the light projecting elements 10 to 12, as shown in FIG. In this case, the respective center lines of the light projecting elements 10 to 12 are the projecting lens 13A.
Is oriented to pass through the center of. By the light projecting elements 10 to 12 and the light projecting lens 13A, the visual fields 2A, 2B,
2C (light receiving area) is obtained. These light projecting elements 10 to 1
By providing one light projecting lens 13A common to the two, even if dirt is attached to the surface of this light projecting lens 13A, shadows due to this dirt appear evenly in the fields of view 2A, 2B, 2C. The brightness of 2C decreases uniformly.
Therefore, even if dirt is attached to the surface of the light projecting lens 13A, the brightness of the visual fields 2A, 2B, and 2C does not vary, and erroneous detection due to this does not occur. In the optical system shown in FIG. 2, when the number of light projecting elements is larger than the number of fields of view, a plurality of light projecting elements are made to project one field of view in an overlapping manner. Although the light projecting elements 10 to 12 and the light projecting lens 13A are provided separately, the light projecting elements 10 to 12 may be formed integrally with the light projecting lens 13A. Further, the entire width of the detection area formed by the visual fields 2A, 2B and 2C (the outer edge of the visual field 2A and the visual field 2C).
The distance from the outer edge of the
The width is set larger than the width of the white line 1.

In FIG. 1, each of 14, 15 and 16 is a light receiving element such as a phototransistor or a photoconductive cell, and a field of view 2 of the light projected by the light projecting elements 10 to 12.
The reflected light from A, 2B and 2C is received. As shown in FIG. 4, a light receiving lens (convex lens) 13B is arranged in front of these light receiving elements 14 to 16. In addition, the light receiving element 14
Nos. 16 through 16 are oriented so that their respective center lines pass through the center of the light projecting lens 13B. The light receiving element 14 receives the reflected light of the light projected by the light projecting element 10, and the light receiving element 15 receives the reflected light of the light projected by the light projecting element 11. Further, the light receiving element 16 receives the reflected light of the light projected by the light projecting element 12. Light receiving element 14-1
Reference numeral 6 denotes the light projecting element 10 corresponding to the visual fields 2A, 2B and 2C.
Like Nos. 12 to 12, they are arranged in parallel at a constant interval in the direction perpendicular to the traveling direction of the vehicle. Further, the light receiving elements 14 to 16
The light projecting elements 10 to 12 are arranged in parallel at a predetermined interval as shown in FIG. The light emitting elements 10 to 12 and the light receiving elements 14 to 16 having the same structure are also attached to the left end of the front part of the vehicle. That is, the same thing is attached to the left and right of the front part of the vehicle. The light receiving element 14
16 to 16 and the light receiving lens 13B are provided separately, the light receiving elements 14 to 16 may be formed integrally with the light receiving lens 13B.

In FIG. 1, reference numerals 17, 18, and 19 denote drive circuits for pulse-driving the light projecting elements 10 to 12, and 20 denotes a timing circuit for controlling the drive timing of the light projecting elements 10 to 12, as shown in FIG. Light emitting elements 10 to 1 at timing
2 is turned on to illuminate each of the light receiving visual fields 2A, 2B and 2C in a time division manner. By making the light emitting elements 10 to 12 pulse-lighted, it becomes possible to reduce the influence of ambient light. Two
Each of 1, 22, and 23 is an amplifier circuit, and the light receiving element 14
The light reception signals output from ˜16 are amplified to a predetermined level and output. Each of 24, 25, and 26 is a demodulation circuit, which outputs a DC signal proportional to the magnitude of the light-receiving signals output from the light-receiving elements 14 to 16. In this case, the operation timing of the demodulation circuits 24 to 26 is synchronized with the drive timing of the light projecting elements 10 to 12. That is, the light projecting element 10
The demodulation circuit 24 operates in synchronization with the driving of the
The demodulation circuit 25 operates in synchronization with the driving of the
The demodulation circuit 26 operates in synchronization with the driving of the. In this way, the demodulation circuits 24-2 are synchronized with the driving of the light projecting elements 10-12.
6 is operated, it is possible to eliminate crosstalk between the light receiving elements 14 to 16 which is likely to occur when a water droplet is attached to the surface of the light receiving lens 13B.

Reference numeral 13 is a threshold value generation circuit, which is a demodulation circuit 25.
The output DC signal is multiplied by M (1>M> 0) to generate a threshold value for the amount of light received by the light receiving elements 14 and 16. That is, among the light receiving elements 14 to 16, the light receiving elements 14 located on both sides depending on the amount of light received by the light receiving element 15 located in the center,
A threshold value for the 16 received light amounts is generated. Each of 29 and 30 is a comparator, and the comparator 29 compares the threshold value output from the threshold value generation circuit 13 and the DC signal output from the demodulation circuit 24 (corresponding to the amount of light received by the light receiving element 14), The comparator 30 compares the threshold value output from the threshold value generation circuit 13 with the DC signal output from the demodulation circuit 26. In this case, the output of the comparator 29 becomes “0” when the DC signal output from the demodulation circuit 24 becomes larger than the threshold value output from the threshold value generation circuit 13. Further, the output of the comparator 30 becomes “0” when the DC signal output from the demodulation circuit 26 becomes larger than the threshold value output from the threshold value generation circuit 13. Here, only when the white line 1 comes on the light receiving element 15 at the center, the outputs of the comparators 29 and 30 both become "1". In other cases, it becomes "0". An AND gate 31 outputs "1" only when both the outputs of the comparators 29 and 30 are "1".

The light emitting elements 10 to 12 and the light receiving element 14 to
16, drive circuits 17 to 19, timing circuit 20, amplification circuits 21 to 23, demodulation circuits 24 to 26, threshold value generation circuit 1
3, the comparators 29 and 30, and the AND gate 31 constitute the optical detection device 100. An optical detection device 110 having the same configuration as the optical detection device 100 is also provided on the left side of the vehicle front portion. 32 is CP
U, and controls to operate the R alarm device 33 and the L alarm device 34 based on the outputs of the optical detection devices 100 and 110. This CPU has a ROM and a RAM (not shown) built therein (a so-called one-chip CPU), and the ROM has a CPU.
A program for controlling is written. The RAM is also used as a working area. CP
U32 operates the R alarm device 33 when the output of the optical detection device 100 is "1", and operates the L alarm device 34 when the output of the optical detection device 110 is "1". The R alarm device 33 and the L alarm device 34 generate a buzzer or a voice synthesizer or blink a light, and are mounted on the operation panel of the driver's seat so as to be separated from each other. The alarm may be supplied as a voice signal to a speaker such as a car radio or car stereo. Further, the alarm may be gradually increased as the white line 1 detection time elapses.
Further, the warning may be given by displaying an image or vibrating the seat.

The light projecting elements 10 to 12 correspond to the light projecting means, and the driving circuits 17 to 19 correspond to the driving means. The light receiving elements 14 to 16 correspond to light receiving means. Further, the threshold value generation circuit 13, the comparators 29 and 30, the AND gate 31, and the CPU 32 constitute the detection means 130. Further, the comparator 29 corresponds to the first comparing means, and the comparator 30
Corresponds to the second comparison means. Further, the AND gate 31 corresponds to a computing means. The timing circuit 20 corresponds to the timing means. The threshold value generation circuit 13 corresponds to the first threshold value generation means.

In such a structure, the light projecting elements 10 to 10
12 are sequentially turned on at a predetermined interval, and the respective reflected lights are received by the light receiving elements 14 to 16. Then, the received light signals output from the respective light receiving elements 14 to 16 are amplified by the amplifier circuits 21 to 2.
After being amplified at 3, the demodulation circuits 24 to 26 demodulate. The DC signal output from the demodulation circuit 24 is supplied to the comparator 29, and the DC signal output from the demodulation circuit 26 is supplied to the comparator 30. Further, the DC signal output from the demodulation circuit 25 is M (1> M) in the threshold generation circuit 13.
> 0) and is supplied to the comparators 29 and 30.

Then, the comparator 29 compares the DC signal output from the demodulation circuit 24 with the threshold value set in the threshold value generation circuit 13, and the DC signal output from the demodulation circuit 24 is higher than the threshold value. If it is larger, "0" is output.
Further, the comparator 30 compares the DC signal output from the demodulation circuit 26 with the threshold value set in the threshold value generation circuit 13, and if the DC signal output from the demodulation circuit 26 is larger than the threshold value, " 0 "is output. On the contrary,
If the DC signal output from the demodulation circuit 24 is smaller than the threshold value, "1" is output, and if the DC signal output from the demodulation circuit 26 is smaller than the threshold value, "1" is output. When the outputs of the comparators 29 and 30 are "0", the output of the AND gate 31 is "0", and when the outputs of the comparators 29 and 30 are "1", the output of the AND gate 31 is "
It becomes 1 ”.

When the output of the AND gate 31 becomes "1", the CPU 32 determines that the white line 1 is detected and operates the R alarm 33 to move the vehicle to the right side of the driver to reach the white line 1. Tell what you have done. On the other hand, the output of the AND gate (not shown) of the optical detection device 110 is "
When it becomes 1 ", the CPU 32 determines that the white line 1 is detected and operates the L alarm 34 to notify the driver that the vehicle has approached the left side and reached the white line 1. Thus, the center The white line 1 is detected only when the white line 1 comes on the visual field 2B of the light receiving element 15. That is, as shown in Fig. 7A, the central visual field 2B is more sensitive to the white line 1 than the visual fields 2A and 2C on both sides thereof. The output of the AND gate 31 becomes "1", that is, "on" only when the ratio of occupation is large, so that there is no dead zone as in the two-view type shown in Fig. 7B. As shown in (c), even if there is a split road surface, it will not be detected.

Example 2. FIG. 6 is a block diagram showing the configuration of a white line detection device to which the second embodiment of the optical detection device according to the present invention is applied. This white line detection device detects a white line or a yellow line on a road. In this figure, the same parts as those in FIG. 6 described above are designated by the same reference numerals and the description thereof will be omitted. In the figure, reference numerals 27 and 28 each denote a threshold value generation circuit, which multiplies the DC signals output from the demodulation circuits 24 and 26 by N (> 1) to generate a threshold value for the amount of light received by the central light receiving element 15. That is, the light receiving elements 14 and 16 on both sides
A threshold value for the amount of light received by the central light receiving element 15 is generated based on the amount of received light. Here, FIG. 5 is a diagram showing changes in the amount of received light with respect to the degree of dirt on the asphalt. The left side is the amount of received light when detecting asphalt without white stains (for example, dirt due to dirt on the trail of a dump truck), the center is the amount of received light when detecting asphalt with white stains,
The right side is the amount of received light when detecting asphalt without white stains. Also, the chain line shown in this figure is the threshold value, the lower side is the threshold value for asphalt without stain, and the upper side is the threshold value for white stain asphalt.

If the threshold value for asphalt without stain is fixed, white stain asphalt may be erroneously detected. Therefore, instead of directly comparing the amount of light received by the light receiving elements 14 and 16 with the amount of light received by the light receiving element 15, by amplifying and comparing the amount of light received by the light receiving elements 14 and 16, the white stain asphalt may be erroneously detected. There is no. In this case, it is advisable to set the amplification factor such that the threshold value when white dirt asphalt is detected becomes the level shown by the upper chain line in this figure. Of course, the threshold value is set to the light receiving elements 1 on both sides.
Since it is proportional to the amount of light received at 4 and 16, the above relationship is maintained even if the surface of the light receiving lens 13B becomes dirty.

The output of the comparator 29 becomes "1" when the DC signal output from the demodulation circuit 25 becomes larger than the threshold value output from the threshold value generation circuit 27. In other words, when the light receiving amount of the light receiving element 15 in the center becomes larger than the light receiving amount of the light receiving elements 14 on both sides by N (> 1).
The output of the comparator 30 is the demodulation circuit 25.
When the output DC signal becomes larger than the threshold value output from the threshold value generation circuit 28, it becomes "1". In other words, it becomes "1" when the light receiving amount of the central light receiving element 15 becomes larger than the light receiving amount of the other light receiving element 16 on both sides multiplied by N (> 1).

The light emitting elements 10 to 12 and the light receiving element 14 to
16, drive circuits 17 to 19, timing circuit 20, amplification circuits 21 to 23, demodulation circuits 24 to 26, threshold value generation circuit 2
7, 28, comparators 29 and 30, and AND gate 31 form an optical detection device 101. An optical detection device 111 having the same configuration as the optical detection device 101 is also provided on the left side of the vehicle front portion.

The threshold value generating circuits 27 and 28 and the comparator 2
9, 30, the AND gate 31, and the CPU 32 constitute the detection means 131. Further, the comparator 29 corresponds to the first comparing means, and the comparator 30 corresponds to the second comparing means. Further, the AND gate 31 corresponds to a computing means. The timing circuit 20 corresponds to the timing means. The threshold generation circuit 27 corresponds to the second threshold generation means, and the threshold generation circuit 28 corresponds to the third threshold generation means.

In such a structure, the light projecting elements 10 to 10
12 are sequentially turned on at a predetermined interval, and the respective reflected lights are received by the light receiving elements 14 to 16. Then, the received light signals output from the respective light receiving elements 14 to 16 are amplified by the amplifier circuits 21 to 2.
After being amplified at 3, the demodulation circuits 24 to 26 demodulate. The DC signal output from the demodulation circuit 24 is supplied to the threshold value generation circuit 27, multiplied by N (> 1), and then supplied to the comparator 29. Further, the DC signal output from the demodulation circuit 26 is supplied to the threshold generation circuit 28, and N (>
1) After being multiplied, it is supplied to the comparator 30. Comparator 29
The DC signal output from the demodulation circuit 25 is compared with the threshold value set by the threshold value generation circuit 27, and "1" is output when the DC signal output from the demodulation circuit 25 is larger than the threshold value. To be done.

The comparator 30 compares the DC signal output from the demodulation circuit 25 with the threshold value set in the threshold value generation circuit 28, and the DC signal output from the demodulation circuit 25 is higher than the threshold value. If it is larger, "1" is output.
When the outputs of the comparators 29 and 30 both become "1", the output of the AND gate 31 becomes "1", and when the output of one of the comparators 29 and 30 is "0", the AND gate 31 becomes The output becomes "0". When the output of the AND gate 31 becomes "1", the CPU 32 determines that the white line 1 is detected and operates the R alarm device 33 to inform the driver that the vehicle has approached the white line 1 toward the right side. Inform. When the output of the AND gate (not shown) of the optical detection device 111 becomes "1", the CPU 32 determines that the white line 1 is detected and operates the L alarm 34 to notify the driver of the vehicle. Notify you that you have reached the white line 1 by approaching the left side.

In this way, the white line is detected based on the relative amount of light received between the light receiving elements 14 to 16, and the light receiving amount of the light receiving element 15 arranged at the center is N of the light receiving amounts of the light receiving elements 14 and 16 on both sides. The white line 1 is detected only when it is larger than (> 1) times. That is, as shown in FIG. 7 (a), the output of the AND gate 31 is "1", that is, "on", only when the central visual field 2B occupies the white line 1 more than the visual fields 2A and 2C on both sides thereof. become. Therefore, FIG.
There is no dead zone like the two-view type shown in (b). Further, as shown in FIG. 7C, even if there is a split road surface, it is not detected.

Example 3. FIG. 8 is a block diagram showing the configuration of a vehicle safety device to which the third embodiment of the optical detection device according to the present invention is applied. In this embodiment, a circuit for predicting the white line 1 is added to the structure of the second embodiment, and the same parts as those in FIG. 6 are designated by the same reference numerals and the description thereof will be omitted. It should be noted that the prediction here means a weak notification of an initial degree in a series of notifications with different warning intensities, and specifically, in this case, the approach of the white line 1 to the inside of the vehicle. In this case, the driver is informed of an approach that may be dangerous if the vehicle further approaches. Prediction of white line 1 is
This is performed by the threshold generation circuit 38, the comparators 39 and 40, and the OR gate 41. The threshold generation circuit 38 multiplies the DC signal output from the demodulation circuit 25 by N (> 1) and demodulates the demodulation circuit 2
4, a threshold value is generated for the DC signal output. That is, the threshold value for the light receiving amounts of the light receiving elements 14 and 16 on both sides is generated by the light receiving amount of the central light receiving element 15. The comparator 39 outputs the threshold value output from the threshold value generation circuit 38 and the DC signal output from the demodulation circuit 24 (the light receiving element 14).
(Corresponding to the amount of received light of)). The comparator 40 compares the threshold value output from the threshold value generation circuit 38 with the DC signal output from the demodulation circuit 26.

In this case, the output of the comparator 39 becomes "1" when the DC signal output from the demodulation circuit 24 becomes larger than the threshold value output from the threshold value generation circuit 38. In other words, it becomes "1" when the amount of light received by one of the light receiving elements 14 on both sides becomes larger than N times the amount of light received by the central light receiving element 15. Further, the output of the comparator 40 becomes “1” when the DC signal output from the demodulation circuit 26 becomes larger than the threshold value output from the threshold value generation circuit 38. In other words, when the light receiving amount of the other light receiving element 16 on both sides becomes larger than the light receiving amount of the central light receiving element 15, it becomes "1". OR gate 41
Is the output of at least one of the comparators 39 and 40.
When it becomes 1 ", it outputs" 1 ".
2, light receiving elements 14 to 16, drive circuits 17 to 19, timing circuit 20, amplifier circuits 21 to 23, demodulation circuits 24 to 2
6, threshold value generation circuits 27, 28, 38, comparators 29, 3
0, 39, 40, AND gate 31, and OR gate 4
1 constitutes an optical detection device 102. An optical detection device 112 having the same configuration as the optical detection device 102 is also provided on the left side of the vehicle front portion.
The threshold generation circuit 38, the comparator 39, the comparator 40, and the OR gate 41 are circuits added to perform prediction, and the threshold generation circuits 27 and 28, the comparators 29 and 30,
Together with the AND gate 31, it constitutes a detection means 132 for performing stepwise detection.

In such a structure, when the amount of light received by the light receiving elements 14 and 16 on both sides becomes larger than the threshold value set by the central light receiving element 15, the output of the OR gate 41 becomes "1". As a result, the CPU 32 predicts the white line 1 and blinks the R indicator (for example, lamp) 42 to call the driver's attention. When the white line 1 is detected,
The CPU 32 operates the R alarm device 33 to notify the driver that the vehicle has approached the right side and has reached the white line 1. When the output of the OR gate (not shown) of the optical detection device 112 becomes “1”, the CPU 32 predicts the white line 1 and outputs L.
The display 43 is blinked to call the driver's attention. When the white line 1 is detected, the CPU 32 causes the L alarm 34
To move the vehicle to the left side of the driver and the white line 1
Inform you that you have reached In the white line prediction of this embodiment, the white line 1 and the split road surface cannot be accurately discriminated as in the case of the two-view type, but when the white line 1 is predicted, the driver is notified by light to call attention. With a safe driving system, the driver is not overly stressed.

Example 4. FIG. 9 is a block diagram showing the configuration of the characteristic portion of Embodiment 4 of the optical detection device according to the present invention. In this embodiment, white line detection and prediction are performed based on the relative amount of light received between the light receiving elements 14-16. As shown in the figure, the light receiving amount of the central light receiving element 15 is supplied to the positive input end of the comparator 45, and the light receiving amount of the light receiving element 14 located on the left side of the light receiving element 15 is supplied to the negative input end thereof. N
(> 1) times the received light amount is supplied. In addition, the comparator 46
Of the light receiving element 15 is supplied to the positive input end of the light receiving element 15, and the light receiving amount of the light receiving element 16 located on the right side of the light receiving element 15 is multiplied by N (> 1). It
The output of the comparator 45 is supplied to one input end of the AND gate 47 and is supplied to one input end of the NOR gate 48, and the output of the comparator 46 is supplied to the other input end of the AND gate 47. It is also supplied to the other input end of the NOR gate 48. The output of the AND gate 47 is supplied to the set terminal S of the flip-flop 49, and the output of the NOR gate 48 is supplied to the reset terminal R of the flip-flop 49. A white line detection output is obtained from the output terminal Q of the flip-flop 49.

Comparators 45 and 46, AND gate 4
7, the NOR gate 48 and the flip-flop 49 constitute the detecting means 133. In this configuration, the output of the AND gate 47 becomes "1" when the light receiving amount of the light receiving element 15 at the center becomes larger than N (> 1) times the light receiving amount of each of the light receiving elements 14 and 16 on both sides. , And the flip-flop 49 is set, and the output becomes "1". That is, the white line detection state is set. This state is maintained for a period in which the light receiving amount of the light receiving element 15 at the center is larger than N times the light receiving amount of one of the light receiving elements 14 and 16 on both sides. The light receiving amount of the light receiving element 15 at the center is the light receiving element 1 on both sides.
The white line detection state is released when the amount of light received is smaller than N times the light reception amount of 4 and 16. Here, a description will be given again with reference to FIGS. 11 and 12. In the state shown in (e), the amount of light received by the light receiving element 15 in the center is equal to the light receiving elements 1 on both sides
It becomes larger than N (> 1) times the light receiving amount of each of 4 and 16, and the white line 1 is detected. When the white line 1 is detected, the white line 1 is detected even in the state shown in (d). Then, as shown in (c), when the light receiving amount of the light receiving element 15 in the center becomes smaller than N (> 1) times the light receiving amount of the light receiving elements 14 and 16 on both sides, the detection of the white line 1 is canceled.

Example 5. FIG. 10 is a block diagram showing the configuration of the characteristic part of the fifth embodiment of the optical detection device according to the present invention. This embodiment is similar to the fourth embodiment in that the light receiving element 14
The white line detection and prediction are performed based on the relative amount of received light between 16 and 16. As shown in this figure, the comparator 55
Of the central light receiving element 15 is supplied to the positive input terminal of the comparator 56 and the positive input terminal of the comparator 56, and the negative input terminal of the comparator 55 and the negative input terminal of the comparator 57 receive the light receiving element 14 on the left side. Amount N
(> 1) times the received light amount is supplied. In addition, the comparator 56
To the negative input terminal of the comparator 58 and the negative input terminal of the comparator 58 are supplied with the amount of received light which is N (> 1) times the amount of received light of the light receiving element 16 on the right side. The light receiving amount of the right light receiving element 16 is supplied to the end. In addition, the comparator 58
To the positive input terminal of the comparator 60 and the light receiving amount of the light receiving element 14 on the left side are supplied, and the negative input terminal of the comparator 58 and the negative input terminal of the comparator 59 receive light of the central light receiving element 15. Amount N
(> 1) times the received light amount is supplied.

The output of the comparator 55 is supplied to one input terminal of the AND gate 61 and the second input terminal of the NOR gate 62, and the output of the comparator 56 is supplied to the other input terminal of the AND gate 61. And is supplied to the first input end of the NOR gate 62. The output of the comparator 60 is supplied to the third input terminal of the NOR gate 62, and the comparator 5
The output of 8 is supplied to the fourth input of NOR gate 62.
The output of the comparator 59 is supplied to the fifth input terminal of the NOR gate 62, and the output of the comparator 57 is supplied to the sixth input of the NOR gate 62.
It is supplied to the input terminal. The output of the AND gate 61 is supplied to the set terminal S of the flip-flop 63, and the output of the NOR gate 62 is reset terminal R of the flip-flop 63.
Is supplied to. A white line detection output is obtained from the output terminal Q of the flip-flop 63. The comparators 55 to 60, the AND gate 61, the NOR gate 62, and the flip-flop 63 constitute the detecting means 134.

In this configuration, the amount of light received by the central light receiving element 15 is N times the amount of light received by each of the light receiving elements 14 and 16 on both sides.
AND gate 61 when it becomes larger than (> 1) times
Output becomes "1", the flip-flop 63 is set, and the output becomes "1". That is, the white line detection state is set. This state is maintained for a period in which the light receiving amount of one of the light receiving elements 14 and 16 on both sides is larger than the light receiving amount of the other. Then, the white line detection state is released when the light receiving amounts of the light receiving elements 14 and 16 on both sides become the same. Here, a description will be given again with reference to FIGS. 11 and 12. In the state shown in (e), the light receiving amount of the light receiving element 15 in the center becomes larger than N (> 1) times the light receiving amount of each of the light receiving elements 14 and 16 on both sides, and the white line 1 is detected. When the white line 1 is detected, the white line 1 is detected even in the state shown in (b). Then, as shown in (a), the amount of light received by the light receiving element 15 in the center is on both sides.
When it becomes smaller than N (> 1) times the received light amount of 6, the detection of the white line 1 is canceled.

Example 6. FIG. 13 is a diagram showing an optical system on the light projecting side of Example 6 of the optical detector according to the present invention. In this embodiment, as shown in the drawing, a light projecting lens (convex lens) 6 is provided in front of each of the light projecting elements 10 to 12.
6, 67, and 68 are provided, and these projection lenses 6 are further provided.
One diffraction grating 69 is provided in front of 6, 67 and 68. The diffraction grating (uniformizing means) 69 is a light projecting element 10-12.
The projected light is branched and diffused, and the visual fields 2A, 2B, and 2C are set in the overlapping portions of the three spots of the large circular light obtained by this. With such a configuration, the light amounts in the visual fields 2A, 2B, and 2C are uniform even if the light emitting amounts of the light projecting elements 10 to 12 are varied, and the light projecting lenses 66, 67, 68, and the diffraction grating are used. Even if dirt is attached to 69, the light amounts in the visual fields 2A, 2B, and 2C become uniform. In the optical system shown in FIG. 13, the number of light projecting elements is one or more. Further, as the homogenizing means, a prism array or a diffusing plate can be used in addition to the diffraction grating 69, but a diffractive grating which can branch light in a predetermined direction as compared with a diffusing plate that simply disperses light. Alternatively, a prism array or the like is superior.

Example 7. 14 is a perspective view showing an optical system on the light projecting side of Example 7 of the optical detecting device according to the present invention. In this embodiment, as shown in FIG.
2 and one light receiving / receiving lens 71 common to the light receiving elements 14 to 16. By using one light projecting / receiving lens 71 for projecting and receiving light in this manner, cost reduction can be achieved, and the detection or the detection characteristic depends on the distance variation between the applied device and the object or the road surface. It has the advantage that it is small.

Example 8. FIG. 15 is a perspective view showing an optical system of Example 8 of the optical detecting device according to the present invention. In this embodiment, as shown in the drawing, polarizers (polarizing elements) 73A and 7A arranged in front of the light projecting elements 10 to 12 and in front of the light receiving elements 14 to 16 so that their transmission polarization planes are orthogonal to each other.
3B is provided. That is, it is configured to block light components whose polarization plane does not rotate on the target object. The configuration other than the polarizers 73A and 73B is the same as that of the first embodiment.
Is the same as. This configuration can prevent malfunction when there is a puddle 74 on the road surface. When the polarizers 73A and 73B are not provided, a part of the illumination light is normally inverted on the surface of the puddle 74 and is directed to the light receiving elements 14 to 16,
An extremely large amount of light is received as compared with a dry road surface. In particular, when the puddle 74 exists only in a part of the light receiving field of view, the designed light receiving amount ratio cannot be obtained, so that the device malfunctions. Since the specular reflection light from the puddle 74 maintains the polarization plane direction, if there are the polarizers 73A and 73B, the specular reflection component of the illumination light that is linearly polarized through the light projecting side polarizer 73A is the light receiving side polarizer. Light-shielding element 1
4 to 16 is not reached. On the other hand, since the reflected light on the road surface or the white line 1 always has a polarization rotation component, this configuration enables reliable device operation.

Example 9. FIG. 16 is a perspective view showing the appearance of an unmanned vehicle (vehicle) 80 to which the ninth embodiment of the optical detection device according to the present invention is applied. In this figure, reference numeral 81 is an optical detection device, which detects a white line 82 and outputs a detection signal thereof. The white line detecting portion of the optical detecting device 81 has the same configuration as that shown in FIG. A steering device 83 controls the steering angle of the front wheels 84 based on the detection signal output from the optical detection device 81. A drive device 85 drives the rear wheel 86. The unmanned vehicle 80 advances while correcting the direction by detecting the white line 82. Figure 17 shows an unmanned vehicle 80
3 is a block diagram showing the configurations of an optical detection device 81 and a steering device 83 of FIG. The unmanned vehicle 80 is an unmanned vehicle in a factory, a golf course cart, or the like. In this figure, the light receiving amount of the left light receiving element 14 and the light receiving amount of the central light receiving element 15 multiplied by N (> 1) are compared by the comparator 89, and the result is fetched by the CPU 96. Further, the light receiving amount obtained by multiplying the light receiving amount of the left light receiving element 14 by N (> 1) and the light receiving amount of the central light receiving element 15 are compared by the comparator 90, and the result is fetched into the CPU 96.

The light receiving amount of the left light receiving element 14 and the light receiving amount of the central light receiving element 15 are compared by the comparator 91, and the result is fetched by the CPU 96. Further, the light receiving amount of the light receiving element 14 on the left side and the light receiving amount of the light receiving element 16 on the right side are compared by the comparator 92, and the result is fetched by the CPU 96. Further, the light receiving amount of the light receiving element 15 at the center and the light receiving amount of the light receiving element 16 on the right side are compared by the comparator 93, and the result is fetched by the CPU 96. In addition, the light receiving element 1 in the center
The light receiving amount of 5 and the light receiving amount of the light receiving element 16 on the right side are set to N (> 1)
The doubled amount of received light is compared by the comparator 94, and the result is C
It is taken into PU96. Further, the light receiving amount obtained by multiplying the light receiving amount of the central light receiving element 15 by N (> 1) and the right light receiving element 16
The amount of light received by the CPU is compared by the comparator 95, and the result is calculated by the CPU.
96. The CPU 96 has a ROM and a RAM (not shown) built therein, and a program for controlling the CPU is written in the ROM. RAM
Is used as a working area. The CPU 96 creates a command for controlling the steering angle of the steering device 83 based on the outputs of the comparators 89 to 95. The created command is D
After being converted by the / A (digital / analog) converter 97, it is supplied to the steering device 83.

FIG. 18 is a flow chart showing the control of the CPU 96. Here, the output of the light receiving element with the right field of view in the traveling direction
R "・ The output of the light receiving element that has the left field of view in the direction of travel
L "・ The light receiving element output that has a central field of view in the traveling direction
C "-The gain of each output for setting the reference value is defined as" N (common) ". The conditions are: -The width of the white line 82 is constant-The visual field interval is equal to the width of the white line 82-Unmanned vehicle 80 It is assumed that there is a white line 82 in one of the visual fields at the start of (there may be two visual fields), and the traveling direction levels are A (strong) and B.
(Medium) and C (weak).

In FIG. 18, first, in step S10, the amount of light received by the left light receiving element 14 and the amount of light received by the right light receiving element 16 are compared. In this comparison, if it is determined that the received light amount comparison result is L <R, L <N in step S12.
It is determined whether or not C ≦ R, and if it is determined that L <NC ≦ R, the steering angle is increased to the right in step S14. On the other hand, if it is determined that L <NC ≦ R is not satisfied, it is determined whether or not L <C ≦ R is satisfied in step S16, and L <C ≦ R is satisfied.
If it is determined that C ≦ R, the steering angle is set to the right and middle in step S18. On the other hand, if it is determined that L <C ≦ R is not satisfied, it is determined in step S20 whether L <R <C is satisfied. If it is determined that L <R <C is satisfied, step S2 is performed.
At 2, decrease the steering angle to the right. On the other hand, when it is determined that L <R <C is not satisfied, NL ≦ C and NR ≦ C in step S22.
It is determined whether or not In this judgment, NL
When it is determined that ≤C and NR≤C, this step is repeated, and when it is determined that NL≤C and NR≤C are not satisfied, the process returns to step S10.

On the other hand, if it is determined in the comparison in step S10 that the received light amount comparison result is L> R, step S
At 24, it is determined whether or not L ≧ NC> R, and L ≧
If it is determined that NC> R, the steering angle is increased to the left in step S26. On the other hand, if it is determined that L ≧ NC> R is not satisfied, it is determined in step S28 whether L ≧ C> R is satisfied. If it is determined that L ≧ C> R is satisfied, step S30 is determined.
Turn the steering angle to the middle to the left. On the other hand, if it is determined that L ≧ C> R is not satisfied, then it is determined in step S32 whether C>L> R, and if it is determined that C>L> R, the steering angles are decreased to the left in step S34. To do. On the other hand, C>L>
If it is determined that it is not R, the process proceeds to step S22.

FIG. 19 shows the results of comparing the light-receiving field of view and the received-light amount in different cases. (1) When the received light amount comparison result is L <NC ≦ R, the steering angle is increased to the right. (2) When the comparison result of the amount of received light is L <C <R or L <C = R, the steering angle is set to the middle to the right. (3) When the light receiving amount comparison result is L <R <C, the steering angle is decreased to the right. (4) When the received light amount comparison result is NL ≦ C and NR ≦ C, the vehicle goes straight. (5) When the received light amount comparison result is C>L> R, the steering angle is decreased to the left. (6) When the received light amount comparison result is L = C> R or L>C> R, the steering angle is set to the middle to the left. (7) If the received light amount comparison result is L ≧ NC> R, the steering angle is increased to the left. As can be seen from FIG. 19, the unmanned vehicle 80 of the present example controls the steering device 83 finely and finely based on the stepwise detection result of the white line 82, so that the unmanned vehicle can follow the white line 82 without causing a large meandering or the like. It will run smoothly on its own. In addition, by providing the detection devices 81 on both sides of the unmanned vehicle 80,
If you run along the two white lines, you can further improve the track accuracy of self-sustaining running.

Example 10. Next, a tenth embodiment of the present invention will be described with reference to FIGS. This embodiment is an example in which the optical detection device according to the present invention is applied to a lane detection system in a passenger car, and five light-receiving fields (light-receiving regions) are provided. FIG. 20 is a perspective view showing this passenger car, FIG. 21 is a front view showing this passenger car, FIG. 22 is a plan view showing this passenger car, and FIG. 23 shows the optical system (projecting means, light receiving means, etc.) of this detection device. FIG. 24 is a block diagram showing a control system (detection means, etc.) of the present detection device. The same parts as those of the first embodiment described above are designated by the same reference numerals and the description thereof will be omitted. Further, hereinafter, in the graphic symbols of the comparators 29, 30 and the like, for convenience of explanation, a character "+" is attached in the vicinity of the arrow indicating the input on the larger side when the output becomes "1", and the output is added. The character "-" will be added near the arrow indicating the input on the smaller side when becomes "1". Therefore, for example, the comparator 29 is defined in the drawing as a comparator having an input / output characteristic as shown in the upper right of FIG.

As shown in FIGS. 20 to 22, the detection device 200 according to the present embodiment has a right front wheel 15 of a passenger car 150 (vehicle).
1, the road surface 3 (object surface) below that position is set as a detection target, and five fields of view (light receiving areas) 2
00A to 200E. As shown in FIG. 22, the visual field 230 is also present in front of the left front wheel 152 of the passenger car 150.
The detection device 250 having A to 230E is disposed symmetrically with respect to the left and right. The optical system of the detection device 200 is shown in FIG.
As shown in FIG. 3, it comprises a light projecting means 210 and a light receiving means 220. In this case, the light projecting means 210 disperses the light from the three light projecting elements 211, 212, and 213 and these light projecting elements and uniformly irradiates the light into the light projecting region 214 on the road surface. Means). In this case, the light projecting area 214 has a size including all of the visual fields 200A to 200E.

The light projecting means of the present invention may be any one that irradiates light to the light projecting area including at least all the light receiving areas in this way, and the number of light projecting elements may be one if the light quantity is sufficient. Good. Further, as the homogenizing means, a diffusing plate that disperses light in this way may be used, and even in this case, for example, even if there is a variation in the light amount of the light projecting element, the deviation of the light amount between the light receiving regions due to this variation is reduced, The possibility of malfunction is reduced. However, as shown in the sixth embodiment, if the light from each light projecting element is evenly branched to each light receiving area, even if some of the light projecting elements are not lit at all, each light receiving element is received. Since the ratio of the amount of light between areas does not change, malfunctions may occur as long as the absolute amount of light is secured, even if there is a defect in the light projecting element or the optical surface (in this case, the surface of the diffusion plate) is dirty. In this respect, the embodiment as in Example 6 is more excellent.

The light receiving means 220 includes light receiving areas 200A to 200A.
It has five light receiving elements 221 to 225 that individually receive the reflected light from 200E, and one light receiving lens 226 common to these light receiving elements. In this case, as shown in FIGS. 21 to 23, the light receiving regions 200A to 200E are arranged in a row at regular intervals in a direction perpendicular to the traveling direction of the vehicle to form a detection region having a total width of L5. The width L3 of at least three light receiving areas (for example, the distance between the outer edges of the light receiving areas 200A and 200C) in this detection area is set to be larger than the width of the white line 1 to be detected. Further, as shown in FIGS. 21 to 22, a part of the outer light receiving regions (in this case, the light receiving regions 200C, 200
D, 200E) is located on the outer side in the width direction of the passenger car 150. In addition, in order to efficiently receive light, it is preferable that the light receiving elements 221 to 225 are arranged at positions where the images of the light receiving areas 200A to 200E are formed.
Further, each light receiving element can be composed of a single photodiode, CCD or the like as described in the first embodiment, but each light receiving element of the present invention may be composed of a plurality of photodiodes. Alternatively, the CCD may be divided into areas.

Then, the control system of the detection device 200 of the present embodiment, as shown in FIG.
To 200E, three continuous (adjacent) light receiving areas are selected, and among the light receiving elements 221-225, three light receiving elements corresponding to these selected light receiving areas (hereinafter, referred to as inner light receiving areas). In order from the light receiving element 201,
202 and 203. ) Is used to detect the white line. That is, in the case of the present example shown in FIG. 24, the light receiving element 202 in the light receiving area located in the center of the three selected light receiving areas is used as a reference, and the threshold value generation circuit 232 uses the output of the light receiving element 202 as a reference. A threshold value is generated, and the threshold value is compared with the signals based on the outputs of the light receiving elements 201 and 203 corresponding to the light receiving areas on both sides by the comparators 29 and 30, respectively.
Here, the threshold value generation circuit 232, the comparators 29 and 30, and the CPU 32 constitute the detection means 230.

In this case, the threshold value generation circuit 232 is set with two kinds of magnifications M and N (gain), and these magnifications are switched alternately by the signal of the timing circuit 231. The first magnification M is 0 <M
<1 and the second magnification N is N> 1. In this case, the timing circuit 231 outputs a timing signal for intermittently driving the drive circuits 17, 18 and 19 of the light projecting means simultaneously at a predetermined minute interval, and in synchronization therewith (that is, each light projecting element is driven). Each time), and a sequential double tone circuit 2
The operation of operating 4, 25, and 26 is repeated. In addition, the timing signal of the timing circuit 231 causes the threshold value generation circuit 232 to alternately switch the scaling factor from M to N or from N to M every time the operations of the double tone circuits 24, 25, and 26 complete one cycle. At the same time, the CPU 32 performs different processing based on this timing signal when the magnification is M and when the magnification is N. That is, in this case, the CPU 32 activates the alarm device 33 or 34 when both comparators 29 and 30 output "1" when the magnification is M, and when the magnification is N, the comparator 32 operates. From either 29 or 30
When "0" is output, the alarm device 33 or 34 is set to operate.

Therefore, in the above-mentioned white line detection system, first, when there is a normal portion (asphalt surface) of the road surface 3 in any of the light receiving regions of the respective light receiving elements 201 to 203,
Since the outputs of the light receiving elements are substantially the same, "0" is given when the magnification is M, and "1" is given when the magnification is N,
Both of the comparators 29 and 30 output, and C
The processing of PU32 does not activate the alarm. However, when the white line 1 reaches the light receiving area of the outer light receiving element 203 by approaching or riding on the white line 1 on the road surface 3, for example, the light receiving amount of the light receiving element 202 in the central light receiving area is smaller than that of the light receiving element 202 in the central light receiving area. Since the amount of light received by the light receiving element 203 on the outer side is remarkably large, "0" is output from the comparator 29 when the magnification is N, and the alarm device 33 on the right side is activated by the processing of the CPU 32. To do. Further, when the vehicle moves further to the right and the white line 1 widely reaches the light receiving area of the central light receiving element 202, this time, the light receiving element 202 of the central light receiving area 202
The light receiving amount of the light receiving element 203 on the outer side and the light receiving element 20 on the inner side
Since it is significantly larger than 1, the comparators 29 and 30 both output "1" when the magnification is M, and the CPU 32 processes the alarm device 33 on the right side. Further, when the vehicle moves further to the right and the white line 1 broadly reaches the light receiving area of the inner light receiving element 201, the light receiving amount of the light receiving element 201 in the inner light receiving area becomes much larger than that of the light receiving element 202 in the center. Therefore, when the magnification is N, "0" is output from the comparator 30, and in any case, the alarm device 33 on the right side is activated.

As described above, with the detection device 200 of this embodiment, the white line 1 can be detected and the alarm 33 can be activated without causing a dead zone in a wide detection region. In the configuration of the control system, when the split road surface comes into the detection area and the magnification is N, the comparator 29,
The output of 30 has the same result as the case where the white line 1 comes, and the alarm device may be activated by mistake, but since only the central light receiving area does not become significantly brighter, the magnification is M The outputs of the comparators 29 and 30 are never "1". Therefore, for example, the CPU 32 is connected with the same indicators 42 and 43 (which give a weak alarm) as in the third embodiment, and when the magnification is M, both the comparators 29 and 30 output "1". When the alarm device 33 or 34 is operated and the magnification is N and any one of the comparators 29 and 30 outputs "0", the display device 42 on the corresponding side.
Alternatively, setting 43 to activate will give the driver a more gradual and non-misleading stepwise warning. That is, when the magnification is N, the white line 1 can be detected earlier (at a position farther outward from the vehicle), but there is a possibility that the white line 1 is erroneously recognized as a split road surface. At the time of detection, a weak visual warning is given on the display (that is, caution that the danger is expected if going in this direction), while when the magnification is M, the white line 1 is mistaken for a split road surface. The white line 1 is closer to the inside of the vehicle in this case, so a strong warning such as a buzzer sound is generated at the time of detection in this case (the risk of danger is high. Warnings, etc. are given in gradual and detailed warnings.

Further, in the above embodiment, since the white line is detected based on the relative output of the light receiving amount of each light receiving element as in the first embodiment, the fluctuation of the absolute value of the light emitting amount and the reflection of the road surface 3 are detected. Depending on the variation in the rate (thing that is not local),
No malfunction occurs. Further, in the above embodiment, five light receiving areas and light receiving elements corresponding to the light receiving areas are provided, and detection is performed by three of the light receiving areas. Therefore, the position of the detection area with respect to the vehicle is selected by selecting three light receiving elements. 22 can be arbitrarily and easily changed as indicated by the symbols R1 to R3 in FIG.

Further, in the above-described embodiment, since one light-receiving lens 226 is shared by the respective light-receiving elements as in the case of the first embodiment, the optical surface (that is, the surface of the light-receiving lens 226 in this case) is free from dirt and the like. Even if dirt (a light shield) is attached, the relative output of the light receiving element is not affected, and such an effect that the malfunction due to the light shield does not occur is also obtained. That is, for example, as shown in the right column of FIG. 25, if the three light receiving elements are provided with separate light receiving lenses, for example, when stains are unevenly attached to the central light receiving lens as shown in FIG. Since only the output of the light receiving element in the center corresponding to the light receiving lens is relatively lowered, it is determined that the output of each light receiving element becomes uniform and the white line is detected even if the white line is in the center as shown in FIG. Not activated (alarm does not work)
Probability is high. However, as shown in the left column of FIG.
With a configuration in which one common light-receiving lens is provided for three light-receiving elements, the output value of each light-receiving element decreases uniformly even if, for example, the light-receiving lens is unevenly stained as shown in the figure. If the white line is in the center, the warning device will work. This is the same regardless of whether there are five light receiving elements or a plurality of light receiving elements. Note that FIG.
In, PD output means photodiode (light emitting element)
Means output.

The above embodiment may have various modifications (modifications) other than the embodiment described later. For example, in FIG.
Although not shown in FIG. 3, a light projecting lens that concentrates the light, which is emitted from the light projecting elements 211, 212, and 213 and is dispersed by the diffusion plate 215, in the light projecting region 214, may be provided, if necessary. In this case, for example, by arranging each element of the optical system as shown in FIG. 26, one convex lens 290 (projecting / receiving lens) can function as both a receiving lens and a projecting lens. Note that FIG.
, The plurality of light receiving elements 2 are arranged in the direction orthogonal to the paper surface.
21 to 225 or a plurality of light projecting elements 211 to 213 are arranged.

In the control system shown in FIG. 24, three of the five light-receiving regions are selected and the determination for detection is made without changing the selection. The combinations of areas (that is, three light receiving elements) are sequentially shifted one by one, as indicated by reference signs R1 to R3 in FIG. 22, based on the signal of the timing circuit 231, and three light receiving elements for detection are detected. The detection determination can be performed while changing the element. In this case, the three light receiving areas located in the center sequentially change among 200B, 200C, and 200D. Therefore, for example, three types of notification means having different warning intensities are provided as notification means connected to the CPU 32, The light receiving area 200D located outside the
When the white line 1 is detected by the magnification M in the state of being in the center of the individual pieces, a relatively weak warning means is activated,
When the white line 1 is detected by the magnification M in a state where the light receiving areas 200C are at the center of the three light receiving areas, the warning means of a medium warning intensity is activated, and the light receiving areas 200B located at the innermost side of the vehicle are at the center of the three light receiving areas. White line 1 with magnification M in the state
When is detected, it becomes possible to perform control such as activating the notification means having the highest intensity, and it is possible to detect the finer white line 1 and notify based on this.

Further, in the control system shown in FIG. 22, the magnification of the threshold value generating circuit 232 is alternately switched to the above-mentioned M or N to perform the detection determination, but it may be fixed to any one of the determinations. it can. In this case, it is not necessary to input the output signal of the timing circuit 231 to the threshold generation circuit 232 or the CPU 32. In addition, in the control system shown in FIG.
There may be a configuration in which the threshold generation circuit 232 is deleted and the outputs of the demodulation circuits are directly compared. In this case, there is an advantage of simplifying the configuration of the control system, but without the threshold value generation circuit 232, the detection sensitivity depends only on the characteristics of the comparator, and the sensitivity becomes appropriate considering noise such as external light. Since the degree of freedom in design for setting is reduced, the configuration having the threshold value generation circuit is superior in this respect.

Further, there may be a mode in which the white line is detected based on the outputs of all the five light receiving elements. For example, 5
Among the light receiving elements, a threshold value generated by multiplying the output of this light receiving element by, for example, N (1 <N) with reference to the output of the light receiving element corresponding to the innermost light receiving area, and the other four light receiving elements If the output of each of the four light receiving elements is compared with each other and it is determined that the white line is detected when any of the outputs of the four light receiving elements becomes larger than the threshold value, any one of the four light receiving elements is detected. The detection position of the white line (the degree of approach to the vehicle center) can be determined in four stages depending on whether the output of (1) exceeds the threshold value. In this case, at least the entire width L5 (the distance between the outer edges of the light receiving areas 200A and 200E located on both outermost sides in this case) of the detection area including the five light receiving areas is the width of the white line 1 to be detected. It should be set larger than. Further, in the above embodiment, an example in which the position of the optical system (the position of the light receiving area) is fixed is shown, but the detection position can be changed by supporting the optical system such as the light receiving element and the light receiving lens so that the position can be changed. The position of a lane such as a white line with respect to the vehicle may be determined based on this. Also in the configuration of the present embodiment, like the twelfth embodiment to be described later, a stop line other than the lane is detected by the processing of the CPU 32 (determination processing based on whether the detection signals are output from the left and right detection devices). It can also be detected.

Example 11. Next, an eleventh embodiment of the present invention will be described with reference to FIG. This embodiment is a modification of the tenth embodiment, and since the mounting position of the detection device in the passenger car and the structure of the optical system of the detection device are the same as those of the above-described tenth embodiment, the parts common to the tenth embodiment will be described. Are assigned the same reference numerals and explanations thereof are omitted. FIG. 27 is a block diagram showing the control system of the detection apparatus of this embodiment (in the figure, the detection apparatus shows only the detection apparatus 300 on the right side). The control system of the eleventh embodiment is similar to the control system of the tenth embodiment shown in FIG.
While the central light receiving element of the three selected is used as the reference, the output of the light receiving element 201 corresponding to the light receiving area located on the innermost side of the vehicle is used as the reference, as shown in FIG.

That is, the demodulation circuit 24 of the light receiving element 201.
A threshold value generation circuit 232 is connected to the output side of each of the comparators 29 and 30 and the threshold value generated by the threshold value generation circuit 232 and the signals based on the outputs of the light receiving elements 202 and 203 corresponding to the outer light receiving areas are compared. It is designed to compare each. Then, in the CPU 32, the threshold generation circuit 2
When the magnification of 32 is M, the comparator 29
When "0" is output from the comparator 30 and "1" is output from the comparator 30, the corresponding alarm device 33 is activated, and at the timing when the magnification is N, both the comparator 29 and the comparator 30 output "0". When "1" is output, the alarm device 33 is set to operate.

Therefore, in the above-mentioned white line detection system, first, when there is a normal portion (asphalt surface) of the road surface 3 in any of the light receiving regions of the respective light receiving elements 201 to 203,
Since the outputs of the respective light receiving elements are substantially the same, when the magnification is M, "1" is output from the comparator 29 and "0" is output from the comparator 30, and when the magnification is N. Is
The comparator 29 outputs "0" and the comparator 30 outputs "0".
1 "will be output, and the alarm device 33 will not be activated by the processing of the CPU 32. Further, even when the white line 1 reaches the outer light receiving area corresponding to the light receiving element 203, the comparison is made in the case where the magnification is N. The result is the same only when the output from the vessel 30 changes to "0." However, for example, when the right side of the vehicle approaches or runs on the white line 1 on the road surface 3,
When the white line 1 widely reaches the light receiving area of the central light receiving element 202, only the amount of light received by the light receiving element 202 in the central light receiving area becomes significantly larger than the amount of light received by the inner light receiving element 201. Therefore, the magnification is N In some cases comparator 29 and comparator 30
"1" is output from both of the CPU3 and the CPU3.
In the process of 2, the alarm device 33 on the right side is activated.

Further, when the white line 1 reaches further to the light receiving area of the inner light receiving element 201 as the vehicle further shifts to the right, the light receiving amount of the light receiving element 201 in the inner light receiving area is changed to another light receiving element 202 or light receiving area. Since it is much larger than the element 203, the comparator 29 outputs “0” when the magnification is M.
Is output and "1" is output from the comparator 30, and the alarm device 33 on the right side is activated by the processing of the CPU 32. When a split road surface with high reflectance from the right side to the light receiving area in the center of the vehicle comes in, the magnification is N
When the magnification is M, the comparator 29 outputs "1" and the comparator 30 outputs "0". When the magnification is M, the comparator 29 outputs "1". Since "0" is output from the comparator 30, the alarm device 33 does not operate by the processing of the CPU 32.

As described above, in the detection device 300 of this embodiment, the white line 1 is detected in a wide detection area and the alarm device 33 is carefully selected without causing a dead zone and causing a malfunction on the split road surface. Can be activated. According to the configuration of the control system, the magnification is M
When the alarm device is activated by the processing when
When the magnification is N, the white line 1 is located further inward than when the alarm device is activated. Therefore, it is possible to make a reliable and stepwise notification by using this.
That is, for example, when the display devices 42 and 43 (which give a weak alarm) similar to those of the third embodiment are connected to the CPU 32, and when the magnification is N, both comparators 29 and 30 output "1". , The display 42 or 43 is activated, and the magnification is M
In this case, if the comparator 29 outputs “0” and the comparator 30 outputs “1”, the alarm device 33 or 3 is output.
Setting 4 to activate will give the driver a more detailed and erroneous step-by-step warning.

Example 12 Next, a twelfth embodiment of the present invention will be described with reference to FIGS. This embodiment is a modification of the tenth embodiment, and the mounting location of the detection device in the passenger car, the structure of the optical system of the detection device, and the like are the same as those of the tenth embodiment.
The same parts as those of the tenth embodiment are designated by the same reference numerals, and the description thereof will be omitted. FIG. 28 is a block diagram showing the control system of the detection device 400 of this embodiment, and FIG.
Is a diagram showing various modes of output of a plurality of light receiving elements in this example, and FIG. 30 is a diagram showing comparison results (outputs from respective comparators) corresponding to various modes of output of the light receiving elements. As shown in FIG. 28, the control system of the eleventh embodiment uses the output of the light receiving element 201 corresponding to the light receiving area located on the innermost side of the vehicle out of the three selected light receiving areas as a reference. Two threshold generation circuits that generate a threshold are provided. Further, the control system of the eleventh embodiment detects stop lines other than lanes (those extending along the traveling direction of the vehicle), road surface indications of pedestrian crossings, etc. (those extending substantially perpendicular to the traveling direction of the vehicle). It also has a function to do.

That is, the demodulation circuit 24 of the light receiving element 201.
On the output side of the threshold generation circuit 432 and the threshold generation circuit 433
Are connected in parallel, and these threshold value generation circuits 432, 433 are connected.
Comparing the threshold values generated by the comparators with the signals based on the outputs of the light-receiving elements 202 and 203 corresponding to the central and outer light-receiving regions by the comparators 441 to 444, respectively, and by the processing of the CPU 32 based on the outputs of these comparators. An alarm device etc. is activated. Here, the threshold generation circuit 43
2 indicates that the signal output from the demodulation circuit 24 based on the timing signal of the timing circuit 431 is multiplied by M (0 <M <
1) to output a signal (threshold value SM),
Further, the threshold value generation circuit 433 is a signal (threshold value SN) obtained by multiplying the signal output from the demodulation circuit 24 by N times (1 <N) each time.
Is output. Further, the comparators 441 to 444 are
The comparator 44 has the same function as that of the comparator 29 described above.
1 compares the threshold value SM with the output of the demodulator 25, and the comparator 4
42 compares the threshold SM with the output of the demodulator 26, the comparator 443 compares the output of the demodulator 25 with the threshold SN, and the comparator 444 compares the output of the demodulator 26 with the threshold SN. Has become. In this case, the timing circuit 431 outputs a timing signal for intermittently driving the drive circuits 17, 18 and 19 of the light projecting means at a predetermined minute interval at the same time, and in synchronization with this, a sequential tone control circuit 24, 25 and 26. Is working.

The CPU 32 has a signal generation circuit 32.
Lane alarms 33, 34 and display 42 via A,
43 is connected, and based on the outputs of the comparators 441 to 444, for example, a process for operating each alarm device and the like is set as follows. That is, each of the comparators 441 to 444
Is shown in FIG. 30 in accordance with the output mode (correctly, the output mode of the demodulators 24 to 25) a to g of the light receiving elements 201 to 203 (numbers 1 to 3 in the figure) shown in FIG. Indicates the output result. Therefore, in the processing of the CPU 32, in the output mode of the comparison result shown in FIG. 30, in the case of the mode d (1111), it is determined that the road surface is present and the alarm device and the like are not all activated. (0011), aspect e
(1100), mode f (1011), or mode g (01
In the case of 11), the indicator 42 is activated because the white line may be detected, and in the case of the mode a (1101), the alarm device 33 is activated because the white line is surely detected. Is set to.

Further, the CPU 32 is connected with a stop line indicator 440 which indicates that a stop line or the like has been detected, and the following stop line detection processing is also set. That is,
The CPU 32 is a detection device 4 provided on both left and right sides of the vehicle.
When both of the output modes of the comparison results of 00 and 450 are any of the above modes a, b, c, e, f, and g, the stop line indicator 440 is operated.

Therefore, in the above-mentioned white line detection system, first, when there is a normal portion (asphalt surface) of the road surface 3 in any of the light receiving regions of the respective light receiving elements 201 to 203,
Since the outputs of the respective light receiving elements are substantially the same and the output form of the comparison result is the form d (1111), neither the alarm device 33 nor the display device 42 is activated by the processing of the CPU 32. And white line 1
Has reached the light receiving areas on both sides corresponding to the light receiving element 203 or the light receiving element 201, the output form of the comparison result is the form b (1110) or the form c (0011), and the CPU
In the process of 32, only the display 42 is activated. Also, white line 1
Is located over the light receiving areas of the light receiving elements 201 and 202, or when the white line 1 is located over the light receiving areas of the light receiving elements 203 and 202, the output mode of the comparison result is the mode e (1100) or the mode f ( 1011), only the display 42 is operated by the processing of the CPU 32. Further, for example, in the case where a highly reflective portion of the split road surface is located in the light receiving area of the light receiving element 201 and a white line is located in the light receiving element of the light receiving element 203, the output mode of the comparison result is the mode g (0111). From the CP
Only the display 42 is activated by the processing of U32.

Even when the highly reflective portion of the split road surface is located in a part of the light receiving area, the comparison results are output in the modes b (1110), c (0011) and e (1).
100) or mode f (1011), but in this case, since only the display 42 is activated, the driver is not inadvertently given a strong notification. Further, with the above configuration, when the highly reflective portion of the split road surface is located in all of the three light receiving areas, the determination result is the mode d (1111).
Therefore, neither the alarm device 33 nor the display device 42 is activated by the processing of the CPU 32. Also, the total width L of the three light receiving regions
Since 3 is set to be larger than the width of the white line 1 which is the detected portion as described above, the white line 1 is located over each light receiving area, and the determination result is the same as the mode d (1111). Malfunctions are unlikely to occur, but if the reliability is to be further enhanced, the width between the outer edges of two adjacent light-receiving regions among the three light-receiving regions is the white line 1 as shown in the three-view field in FIG. It is preferable to set the width to be larger than the width of the (detected portion).

When the vehicle 150 crosses a stop line, a display of a pedestrian crossing, or the like, the output modes of the comparison results of the detection devices 400 and 450 provided on both left and right sides of the vehicle are the same as the above modes a, b, and Since it is any one of c, e, f, and g, the stop line indicator 440 is operated by the processing of the CPU 32. Therefore, the driver sees the display of the stop line indicator 440 and recognizes that there is a stop line or the like immediately in front of the vehicle, so that the driver can surely comply with traffic regulations such as stopping before the stop line. As a result, it becomes easier to drive safely. When a vehicle crosses a pedestrian crossing display or the like, the comparison result of any one of the above modes a, b, c, e, f, and g may be output, and the display device or the like may operate. There is a problem of erroneous recognition as the detection of the lane 1, but since the detection display of the stop line etc. is separate, the driving vehicle sees this display and the lane is detected, the stop line etc. are detected. Can be distinguished. Further, as will be described later, the alarm devices 33 and 34 of the CPU 32 and the display device 4 are provided.
This problem can be solved by providing an on-delay circuit for delaying the rise of the output signal to the output terminals 2 and 43 so as to ignore the instantaneous input when crossing the stop line or the like.

As described above, the detection device 400 of the present embodiment can detect lanes, stop lines, etc. in a wide detection area and in various modes without causing a dead zone and causing a malfunction on the split road surface. It is possible to detect and give a more detailed notification to the driver. In addition,
In the above embodiment, the alarm device is activated only when the output of the light receiving element corresponding to the central light receiving area among the three is significantly larger than the other light receiving elements. The processing of the CPU 32 for the output mode
Various modifications may be made depending on the conditions such as the width and shape of the white line (detected portion) with respect to the size of the light receiving area, the degree of safety requirement, and the like. For example, with an emphasis on safety, the alarm device may be activated even when the output mode of the comparison result is the mode e (1100) or the mode f (1011).
If the detected part to be detected is a double lane on the road surface (consisting of white lines, etc.),
When the heavy lane is located in the detection area, a comparison result such as the mode g (0111) is obtained. Therefore, the alarm device may be activated in the case of the mode g (0111).

Further, the operation of the alarm device may be determined based on the history (time-series change) of the output form of the comparison result. That is, when a lane such as a white line approaches the vehicle detection area from the outside, for example, mode b (1110)
From aspect a (1101) via aspect e (1100)
Since there should be a time-sequential change such as, the alarm device can be activated only when the mode a (1101) is reached through such a history.
By doing so, even when there is a locally highly reflective portion (for example, a puddle, a convex portion, or the like that is not the detection target) on the road surface, it is possible to prevent malfunction due to such locally highly reflective portion. , A more accurate and stable lane detection warning system. Further, in order to prevent a malfunction due to a locally highly reflective portion or the like and to realize a more stable and proper operation of the alarm device, a so-called on-delay circuit for delaying the rise of the output signal with respect to the input signal in the CPU 32 is provided. Further, it is preferable to provide an off-delay circuit for delaying the rising edge of the output signal in the CPU 32. With this configuration, for example, the white paper or the like that happens to fall on the road surface causes the aspect a (110
In 1), an erroneous operation such as activation of an alarm device is prevented. In addition, the alarm device, which once operated in the mode a (1101), stops due to the mode d (1111) being momentarily caused by, for example, partial peeling of the white line, and the operation is interrupted. It is possible to prevent problems such as being lost.

Further, in the embodiment described above, the light receiving regions are arranged side by side at right angles (in one horizontal line) in the traveling direction of the vehicle as shown in FIG. 22, but as shown in FIG. Light receiving area 4 arranged obliquely to the direction
00A, 400B, 400C, or light receiving area 450
You may set A, 450B, 450C. in this case,
If the distance LX between the outermost edges of the light receiving area in the lateral direction of the vehicle is set larger than the width of the lane, the lane extending in parallel with the traveling direction of the vehicle can be detected by the control system described above, and the stop line detection can be performed. Depending on the function, it is also possible to detect a detected portion extending in the lateral direction such as the stop line T. Also in the stop line detection function, if the interval LY of the outermost edges of the light receiving area in the traveling direction of the vehicle is set to be larger than the width of the stop line T, the finely detailed stepwise detection similar to the above lane detection and Notification is possible. Therefore, with the configuration shown in FIG. 31 or FIG. 32, the detected parts (lanes, stop lines, etc.) in various directions can be detected stepwise without omission, either in the notification function or in the self-sustained travel function. As a result, safer and smoother vehicle traveling can be realized. In this case as well, in the lane detection function, it is possible to prevent the detection of a lane and the detection of a stop line from being confused by assuming that the outputs from the left and right detection devices are simultaneously present. .

Further, in the embodiments described above, lanes, stop lines, etc. on the road surface are exemplified as the detected portion of the present invention, but the present invention also applies to highly reflective portions such as marks on various object surfaces. It goes without saying that it can be detected by the configuration of. Also,
The detected portion of the present invention is not limited to the high reflection portion, but if the relationship of lightness and darkness is reversed, for example, a mark formed of a black line or the like provided on the surface of a white background can be detected with the same configuration. In addition, on the road surface display, lines indicating tracks for unmanned vehicles and so-called road markings such as the above lanes and stop lines (in combination with road signs and traffic signals, traffic regulations, warnings, guidance, and instructions are given. For this purpose, all lines, symbols, characters, etc. that are installed, drawn or affixed on pavement surfaces, curbs, etc. are included. Further, in each of the above embodiments, the detection determination is performed by comparing the outputs of the light receiving elements relatively, but the output of the light receiving elements (output of the demodulation circuit) is directly input to the CPU, for example, to obtain an absolute value. It may be possible to compare with a reference value. Even in this case, by providing three or more light-receiving areas and light-receiving elements corresponding to the light-receiving areas, it is possible to perform finer detection than before.

[0086]

According to the first aspect of the present invention, the detected portion formed on the object surface is formed based on the outputs of at least three light receiving elements that separately receive the reflected light from different light receiving regions on the object surface. To be detected. Therefore, it is possible to optically and finely determine the existence state of marks, irregularities, and the like on the surface of the object by using three or more light receiving regions. For example, even when detecting a high reflection band such as a white line on the road surface, the white line or the like may be detected depending on which of the three or more light receiving elements has a larger amount of received light than a reference value (threshold). It is also possible to determine whether it is on the center side or the end side in the entire area where the light receiving area of is arranged.

According to the second aspect of the invention, the width between the outer edges of the light-receiving areas on both outermost sides, that is, the width of the detection area is set larger than the width of the detected portion to be detected.
Therefore, a white line or the like on the road surface can be reliably detected without causing a dead zone and without being mistaken for a split road surface or the like.

According to the third aspect of the invention, the predetermined detected portion is detected based on the relative output of each light receiving element, that is, by comparing the amount of light received by each light receiving element. Therefore, as compared with the case where the detected portion is determined by comparing the received light amount with an absolute reference value, malfunction does not easily occur even if there is dirt on the optical surface of the device side or dirt on the object surface side.

According to the fourth aspect of the invention, the detected portion is displayed on the road surface. Therefore, it is possible to finely detect the presence status of the road surface display (for example, the proximity status to the vehicle). According to the invention described in claim 5, the unevenness of the light quantity distribution of the light from the light projecting means between the light receiving regions is reduced by the uniformizing means. Therefore, for example, even if the optical surface of the light projecting element is partially contaminated, the decrease in the amount of light due to this contamination is uniform in each light receiving region, and thus erroneous detection due to dirt is unlikely to occur. Further, since a plurality of light projecting elements are provided, and even if there are variations in the amount of light emitted from these light projecting elements, the variations are also uniform in each light receiving region, so that erroneous detection due to this variation does not occur.

According to the sixth aspect of the invention, the light projecting means is composed of a plurality of light projecting elements. Therefore, the amount of light of the light projecting means is increased, and external light (sunlight, light of indoor lighting,
The influence of external light, etc.) can be relatively reduced, and the occurrence of malfunction due to external light can be easily reduced. According to the invention described in claim 7, each light receiving element is provided with a single light receiving lens. Therefore, even if the lens surface becomes dirty, the decrease in brightness due to this dirt becomes uniform in each light-receiving area, and erroneous detection due to this dirt hardly occurs.

According to the eighth aspect of the invention, one light projecting / receiving lens common to the light projecting means and the light receiving means is provided. Therefore, the cost can be reduced, and the dependence of the detection characteristics on the distance variation between the device and the surface of the object to be detected can be reduced. According to the invention described in claim 9, the light projecting means and the light receiving means are provided with the polarizing elements whose transmission polarization planes are orthogonal to each other. Therefore, when a high reflection band such as a white line is detected as the predetermined detected portion, it is possible to reliably distinguish the high reflection band formed of a mirror surface such as a puddle or a glass surface and perform a detection operation without malfunction.

According to the tenth aspect of the invention, the optical detection device of the present invention is mounted on a vehicle, and the road surface display is detected by the driver of the vehicle based on the detection of the road surface display by the optical detection device. A notifying means for notifying the fact is provided. Therefore, it is possible to inform the driver that the road surface display is at a predetermined position with respect to the vehicle and call various cautions. For example, if a centrally separated lane (white line or the like), which is a type of road surface display, is detected, it is possible to give a warning to the driver in order to prevent the driver from driving to the oncoming lane due to drowsiness or the like. According to the invention as set forth in claim 11,
Based on the detection of the road surface display by the optical detection device, the stepwise notification is performed. Therefore, for example, the driver is warned step by step while changing the mode from a weak one to a strong one according to the degree of approach to the vehicle such as a lane, and the driver is not unnecessarily anxious. You can According to the twelfth aspect of the present invention, the optical detection device of the present invention is mounted on a vehicle, and the steering angle control means for controlling the steering angle of the wheel is provided based on the detection of the road surface display by the optical detection device. It was Therefore, for example, by causing the vehicle to travel along the lane, it becomes possible to autonomously drive the vehicle.

According to the thirteenth aspect of the present invention, the optical detecting devices are attached to at least the left and right side portions of the vehicle, respectively. Therefore, the notification function by the notification means or the self-sustained running function by the steering angle control means can be performed more finely and with higher accuracy. Claim 1
According to the invention described in claim 4, at least one of the light receiving areas is set outside the vehicle. Therefore, the notification function by the notification means or the self-sustained travel function by the steering angle control means can be performed more finely and with higher accuracy. According to the fifteenth aspect of the invention, the light receiving areas of the optical detection device are positioned so as to be arranged obliquely with respect to the vehicle traveling direction.
Therefore, even in the notification function or the self-sustaining traveling function, the detected parts (lanes, stop lines, etc.) in various directions can be detected step by step without omission, and safer and smoother traveling of the vehicle can be realized.

[Brief description of drawings]

FIG. 1 is a block diagram showing a configuration of a vehicle safety device to which an optical detection device according to a first embodiment of the present invention is applied.

FIG. 2 is a diagram showing an optical system on a light projecting side of the optical detection device of the first embodiment.

FIG. 3 is a waveform diagram showing a drive pulse of each light projecting element of the optical detection device of the first embodiment.

FIG. 4 is a perspective view showing an optical system on a light projecting side and a light receiving side of the optical detection device of the first embodiment.

FIG. 5 is a diagram showing changes in the amount of light received by the optical detection device of the first embodiment.

FIG. 6 is a block diagram showing a configuration of a vehicle safety device to which an optical detection device according to a second embodiment of the invention is applied.

FIG. 7 is a diagram for explaining the characteristics of the optical detection device of the present invention.

FIG. 8 is a block diagram showing a configuration of a vehicle safety device to which an optical detection device according to a third embodiment of the invention is applied.

FIG. 9 is a configuration diagram of a characteristic part of an optical detection device according to a fourth embodiment of the invention.

FIG. 10 is a configuration diagram of a characteristic part of an optical detection device according to a fifth embodiment of the invention.

FIG. 11 is an explanatory diagram of a characteristic part of the optical detection device according to the fourth and fifth embodiments.

FIG. 12 is an explanatory diagram of a characteristic part of the optical detection device according to the fourth and fifth embodiments.

FIG. 13 is a diagram showing an optical system on a light projecting side of an optical detection device according to a sixth embodiment of the invention.

FIG. 14 is a diagram showing an optical system on a light projecting side and a light receiving side of an optical detection device according to a seventh embodiment of the present invention.

FIG. 15 is a diagram showing an optical system on a light projecting side and a light receiving side of an optical detection device according to an eighth embodiment of the invention.

FIG. 16 is a perspective view showing the appearance of an unmanned vehicle to which the optical detection device according to the ninth embodiment of the invention is applied.

FIG. 17 is a block diagram showing a part of the configuration of an unmanned vehicle to which the optical detection device according to the ninth embodiment is applied.

FIG. 18 is a flowchart showing the operation of the unmanned vehicle to which the optical detection device according to the ninth embodiment is applied.

FIG. 19 is a diagram for explaining the operation of the unmanned vehicle to which the optical detection device according to the ninth embodiment is applied.

FIG. 20 is a perspective view showing a passenger car to which an optical detection device according to a tenth embodiment of the invention is applied.

FIG. 21 is a front view showing a passenger car to which the optical detection device according to the tenth embodiment is applied.

FIG. 22 is a plan view showing a passenger car to which the optical detection device according to the tenth embodiment is applied.

FIG. 23 is a perspective view showing an optical system of an optical detection device according to a tenth embodiment.

FIG. 24 is a block diagram showing a control system of the optical detection device according to the tenth embodiment.

FIG. 25 is a diagram for explaining the function and effect of the optical detection device according to the tenth embodiment.

FIG. 26 is a side view showing an optical system of an optical detection device according to a modification of the tenth embodiment.

FIG. 27 is a block diagram showing a control system of an optical detection device according to an eleventh embodiment of the present invention.

FIG. 28 is a block diagram showing a control system of an optical detection device according to a twelfth embodiment of the present invention.

FIG. 29 is a diagram showing various aspects of outputs of a plurality of light receiving elements in the optical detection device according to the twelfth embodiment.

FIG. 30 is a diagram showing a comparison result (output from each comparator) corresponding to various modes of outputs of a plurality of light receiving elements in the optical detection device according to the twelfth embodiment.

FIG. 31 is a plan view showing an arrangement of light receiving regions in an optical detection device according to a modified example of the present invention.

FIG. 32 is a plan view showing an arrangement of light receiving regions in an optical detection device according to a modified example of the present invention.

[Explanation of symbols]

1 White Line (Detected Part) 2A, 2B, 2C Field of View (Light-Receiving Area) 3 Road Surface (Object Surface) 10-12 Light-Emitting Element (Light-Emitting Means) 14-16 Light-Receiving Element (Light-Receiving Means) 33 R Alarm (Notification Means) ) 34 L alarm device (informing means) 42 R display device (informing device) 43 L display device (informing device) 69 Diffraction grating (uniformizing device) 71 Emitter / receiver lens 73A, 73B Polarizer (polarizing element) 80 Unmanned vehicle ( Vehicle) 82 White line (detected part) 100, 101, 102, 111, 112 Optical detection device 130, 131, 132, 133, 134 Detection means 150 Vehicle 200, 250, 300, 400, 450 Optical detection device 200A- 200E, 250A-250E Light receiving area 210 Light projecting means 211, 215, 213 Light projecting element 215 Diffusion plate (uniformizing means) 220 Light receiving means 221, 2 22, 223, 224, 225 Light receiving element 226 Light receiving lens 230, 330, 430 Detection means 290 Convex lens (light emitting and receiving lens) 440 Stop line indicator (informing means)

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification number Reference number within the agency FI Technical display location G01B 11/00 A G01C 15/00 A G01S 17/66 4240-5J G05D 1/02 E G08G 1 / 16 F 7531-3H

Claims (15)

[Claims] 1. A light projecting means for irradiating an object surface with light, and at least three light receiving elements for receiving reflected light on the object surface of light emitted by the light projecting means,
Based on the outputs of at least three light receiving elements of the light receiving means, each of the light receiving elements is configured to separately receive reflected light from different light receiving areas on the object surface, and formed on the object surface. An optical detection device comprising: a detection unit configured to detect a detected portion such as a predetermined mark. 2. The optical detecting device according to claim 1, wherein the light receiving unit is set such that at least a width between outer edges of the light receiving areas on both outermost sides is set to be larger than a width of the detected portion. 3. The detection means compares the outputs of at least three light receiving elements and detects the detected portion based on the relative outputs thereof.
The optical detection device described. 4. The optical detection device according to claim 1, wherein the object surface is a road surface, and the detected portion is a road surface display. 5. The light projecting means comprises a light projecting element and a uniformizing means for reducing a deviation of a light amount distribution of light from the light projecting element between respective light receiving regions. The optical detection device according to claim 1. 6. The optical detection device according to claim 1, wherein the light projecting means includes a plurality of light projecting elements. 7. The light receiving means includes one light receiving lens common to each light receiving element.
7. The optical detection device according to any one of 1 to 6. 8. A light projecting / receiving lens common to both the light projecting means and the light receiving means is provided, and the light projecting means irradiates light onto an object surface through the light projecting / receiving lens.
7. The optical detection device according to claim 1, wherein the light receiving unit is configured to receive the reflected light from the surface of the object via the light projecting and receiving lens. 9. The optical detecting device according to claim 1, wherein the light projecting unit and the light receiving unit are provided with polarizing elements whose transmission polarization planes are orthogonal to each other. 10. The method according to claim 1, wherein the road surface indication is detected.
A vehicle equipped with the optical detection device according to any one of the items, based on detection of a road surface display by the optical detection device,
A vehicle comprising: a notification unit that notifies a driver of the vehicle that a road surface display has been detected. 11. The vehicle according to claim 10, wherein the notifying unit makes a stepwise notification based on detection of a road surface display by the optical detection device. 12. The method according to claim 1, wherein the road surface indication is detected.
A vehicle equipped with the optical detection device according to any one of the items, based on detection of a road surface display by the optical detection device,
A vehicle provided with a steering angle control means for controlling a steering angle of wheels. 13. The optical detection device is attached to at least left and right side portions of a vehicle, respectively, and based on the outputs of at least these two optical detection devices, the notification means or the steering angle control means notifies or steers the steering angle. 2. The control system according to claim 1, wherein
The vehicle according to any one of 0 to 12. 14. The vehicle according to claim 10, wherein in the optical detection device, at least one light receiving area of each light receiving area is set outside the vehicle. 15. The vehicle according to claim 10, wherein the optical detection device is positioned such that the light receiving regions are arranged obliquely with respect to the vehicle traveling direction.