JP2016117345A - Virtual image display device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a virtual image display device capable of preventing processing load on the device side from becoming large without frequently changing the distance from a user to a virtual image.SOLUTION: A video output from a projector 4 is projected onto a screen 5, and the video projected on the screen 5 is caused to be reflected on a front window 7 of a vehicle 2 so that it is viewed by an occupant 8 of the vehicle, thereby generating a virtual image 9 of the video to be viewed by the occupant 8 of the vehicle. An HUD 1 obtains congestion information for a side ahead in the traveling direction of the vehicle from a VICS center, which is an external server, and controls a generated distance L, which is a distance from the occupant 8 of the vehicle to the virtual image 9, based on the obtained congestion information.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a virtual image display device that displays a virtual image visually recognized by a user.

  Conventionally, various means have been used as information providing means for providing driving information such as route guidance and obstacle warnings to passengers of moving bodies such as vehicles. For example, display on a liquid crystal display installed on a moving body, sound output from a speaker, and the like. In recent years, as one of such information providing means, a head-up display device (hereinafter referred to as HUD) is used in a space different from a position where an image is actually displayed using an illusion of human eyes. There is a virtual image display device for visually recognizing an image.

  For example, as described in JP 2009-150947 A, a HUD installed particularly on a vehicle as a moving body is located in front of a vehicle window (for example, a front window) as viewed from the vehicle occupant and has a foreground with a front view. The driving information (for example, speed display, obstacle warning, route guidance display, etc.) can be generated as a virtual image. As a result, the occupant can reduce the line-of-sight movement as much as possible when visually confirming the driving information, and can further reduce the burden during driving.

  Here, in order to more effectively guide the virtual image, it is important to appropriately set the position (more specifically, the distance from the occupant to the virtual image) where the virtual image is generated. For example, in order to generate a virtual image of a warning for an obstacle, it is desirable to generate a virtual image at a position where the obstacle actually exists. Therefore, in the technique of Patent Document 1, the distance from the occupant to the virtual image can be arbitrarily changed by moving the position of the screen on which the image is projected along the optical path. There has been proposed a technique for detecting the distance to an object and controlling the movement of the screen so that the distance from the occupant to the virtual image coincides with the detected distance.

JP 2009-150947 A (page 9-10, FIG. 1)

  However, in the technique described in Patent Document 1, since the laser sensor is a means for detecting the current distance from the passenger to the obstacle, the screen moves each time the distance from the passenger to the obstacle changes. The distance from the passenger to the virtual image will also change. As a result, the distance from the occupant to the virtual image frequently changes according to the distance from the occupant to the obstacle, and there is a problem that it is difficult for the occupant to visually recognize the virtual image. There is also a problem that the processing load on the apparatus side related to the movement of the screen becomes large.

  The present invention has been made to solve the above-described conventional problems. Since the distance from the user to the virtual image is controlled based on the wider area information acquired from the external server, the distance from the user to the virtual image is frequently set. It is an object of the present invention to provide a virtual image display device that prevents the processing burden on the device side from increasing without changing to the above.

  In order to achieve the above object, a virtual image display device according to the present invention includes a video display surface that displays a video, and a virtual image generation that generates a virtual image of the video by allowing a user to visually recognize the video displayed on the video display surface. And a traffic information acquisition unit that acquires traffic information ahead of the user in the traveling direction from an external server, and a generation that is a distance from the user to the virtual image based on the traffic information acquired by the traffic information acquisition unit Generation distance control means for controlling the distance.

  According to the virtual image display device according to the present invention having the above-described configuration, the distance from the user to the virtual image is frequently changed because the distance from the user to the virtual image is controlled based on wider area information acquired from the external server. Therefore, it is possible to generate a virtual image that is easy for the user to visually recognize at an appropriate position in consideration of the surrounding situation. Further, it is possible to reduce the processing load on the apparatus side related to the control of the virtual image generation position as compared with the conventional case.

It is the figure which showed the installation aspect to the vehicle of HUD which concerns on this embodiment. It is the figure which showed the internal structure of HUD which concerns on this embodiment. It is the figure which showed the structure of the projector. It is the figure which showed the screen. It is the figure which showed the inclination aspect of the screen. It is the figure which showed the 1st mirror and the 2nd mirror. It is the figure which showed the change aspect of the optical path length by moving a 1st mirror and a 2nd mirror. It is a figure explaining the production | generation distance of a virtual image. It is the figure which showed the virtual image visually recognized from the passenger | crew of a vehicle. It is the block diagram which showed the structure of HUD which concerns on this embodiment. It is a flowchart of the generation distance change processing program concerning this embodiment. It is the figure which showed an example of the virtual image visually recognizable from the passenger | crew of a vehicle. It is a flowchart of the sub process program of the traffic congestion determination process which concerns on this embodiment. It is the figure which showed an example of the identification method of a traffic congestion degree. It is a flowchart of the sub process program of the production | generation distance control process which concerns on this embodiment. It is a figure explaining the identification method of the control start point. It is a table used for the determination process of optimal generation distance. It is a flowchart of the sub process program of the production | generation distance change process based on the vehicle speed which concerns on this embodiment. It is a flowchart of the sub process program of the control cancellation | release determination process which concerns on this embodiment.

  DESCRIPTION OF EXEMPLARY EMBODIMENTS Hereinafter, a virtual image display device according to the invention will be described in detail with reference to the drawings with regard to an embodiment in which the virtual image display device is embodied in a head-up display device mounted on a vehicle.

  First, the configuration of a head-up display device (hereinafter referred to as HUD) 1 according to the present embodiment will be described with reference to FIG. FIG. 1 is a diagram showing an installation mode of the HUD 1 according to the present embodiment on the vehicle 2.

  As shown in FIG. 1, the HUD 1 is installed inside the dashboard 3 of the vehicle 2, and includes a projector 4 and a screen 5 on which an image from the projector 4 is projected. Then, the image projected on the screen 5 is reflected on the front window 7 in front of the driver's seat through the mirror and concave mirror 6 provided in the HUD 1 as will be described later, and is made visible to the passenger 8 of the vehicle 2. ing. The image projected on the screen 5 includes information related to the vehicle 2 and various information used for assisting driving of the occupant 8. For example, warnings for obstacles (other vehicles and pedestrians), guidance information set by the navigation device, guidance information based on the guidance route (arrows indicating right and left turn directions, etc.), warnings to be displayed on the road surface (attention to rear-end collision, speed limit, etc.) ), Current vehicle speed, information signs, map images, traffic information, news, weather forecast, time, connected smartphone screen, TV program, and the like.

  Moreover, in HUD1 of this embodiment, when the passenger | crew 8 visually recognizes the image which reflected the front window 7 and was projected on the screen 5, it is not the position of the front window 7, but the front of the front window 7 on the passenger | crew 8. An image projected on the screen 5 at a distant position is configured to be visually recognized as a virtual image 9. The virtual image 9 that can be seen by the occupant 8 is an image projected on the screen 5, but the vertical direction and the horizontal direction may be reversed through the concave mirror 6 and the mirror. In this embodiment, as will be described later, the concave mirror 6 and a plurality of mirrors are used, but the image projected on the screen 5 by optimizing the number of mirrors is a virtual image without being inverted in the vertical and horizontal directions. It will be visually recognized as 9. Further, the size is also changed through the Fresnel lens and the concave mirror 6.

  Here, regarding the position where the virtual image 9 is generated, more specifically, the distance L from the occupant 8 to the virtual image 9 (hereinafter referred to as a generation distance) L, the curvature of the concave mirror 6 and Fresnel lens provided in the HUD 1, the screen 5 and the concave mirror 6 It is possible to set appropriately depending on the relative position and the like. For example, if the curvature of the concave mirror 6 or the Fresnel lens is fixed, the generation distance L is determined by the distance along the optical path from the position where the image is displayed on the screen 5 to the concave mirror 6. In the HUD 1 of this embodiment, the position of the mirror that changes the direction of the optical path is moved between the screen 5 and the concave mirror 6 as described later, or the position at which the image is projected onto the inclined screen 5 is changed. The distance can be changed. As a result, the generation distance L can be changed as appropriate. For example, the generation distance L can be changed between 2.5 m and 40 m.

  A front camera 10 is installed above the front bumper of the vehicle, behind the rearview mirror, and the like. The front camera 10 is an imaging device configured by a camera using a solid-state imaging device such as a CCD, for example, and is installed with the optical axis direction facing forward in the traveling direction of the vehicle. Then, by performing image processing on the captured image captured by the front camera 10, the situation of the front environment (that is, the environment in which the virtual image 9 is superimposed) viewed by the occupant 8 through the front window 7 is detected. Is done. A sensor such as a millimeter wave radar may be used instead of the front camera 10.

  Next, a more specific configuration of the HUD 1 will be described with reference to FIG. FIG. 2 is a diagram showing an internal configuration of the HUD 1 according to the present embodiment.

  As shown in FIG. 2, the HUD 1 includes a projector 4, a screen 5, a concave mirror 6, a first mirror 11, a second mirror 12, a reflecting mirror 13, a cover glass 15, a control circuit unit 16, and a CAN. The interface 17 is basically configured.

  Here, the projector 4 is an image projection apparatus using an LED light source, a lamp light source, or a laser light source as a light source, and is, for example, a laser scanning projector. The projector 4 may be a DLP projector, a liquid crystal projector, or an LCOS projector. When a projector other than the laser scanning projector is used, it is necessary to separately arrange a projection lens for the projector 4.

  FIG. 3 is a diagram showing the configuration of the projector 4. As shown in FIG. 3, the projector 4 includes a laser light source 18 inside. For example, in a laser scanning projector, the laser light output from the light source 18 is reflected by the MEMS mirror 19 and scanned on the screen 5. As a result, a desired image is projected onto the screen 5.

  On the other hand, the screen 5 is a projection medium on which an image projected from the projector 4 is projected. For example, a transmissive screen made of a diffusing plate such as ground glass or a microlens array is used. Here, FIG. 4 is a diagram showing the screen 5.

  As shown in FIG. 4, the screen 5 has a projection area 21 as a video projection surface on which a video is projected, and a video projected from the projector 4 using the light from the light source 18 is displayed. That is, the screen 5 corresponds to a video display surface on which video is displayed. In addition, the passenger | crew 8 will visually recognize the image | video projected by the projector 4 from the opposite side to a projection side.

  Further, instead of the projector 4 and the screen 5, a liquid crystal display, an organic EL display, or the like may be used as a means for displaying an image to be visually recognized by the passenger 8. In that case, the backlight of the liquid crystal display or the light emitting element of the organic EL display corresponds to the light source, and the surface on which the image is displayed in the liquid crystal display or the organic EL display corresponds to the liquid crystal display surface.

  The screen 5 is disposed so as to be inclined with respect to the optical path 22 of the light source 18 connecting the screen 5 and the concave mirror 6. More specifically, the generated virtual image 9 is tilted in a direction in which the lower end of the virtual image 9 is positioned closer to the user side than the upper end, that is, in a direction in which the upper end of the screen 5 is on the light source 18 (projector 4) side as shown in FIG. Are arranged. Note that the inclination angle θ of the screen 5 (defined by the inclination from the plane perpendicular to the optical path 22) is a range in which the generation distance L can be changed (for example, 2.5 m to 40 m) and the generated virtual image 9. It is set as appropriate based on the angle of inclination. For example, 3 degrees.

  The concave mirror 6 is a projection mirror that generates a virtual image 9 (see FIG. 1) in front of the occupant 8 by enlarging and reflecting the image displayed on the screen 5 and causing the occupant 8 to visually recognize the image. And a virtual image production | generation means is comprised with the front window 7. FIG. As the concave mirror 6, a spherical concave mirror, an aspherical concave mirror, or a free-form curved mirror for correcting distortion of a projected image is used.

  The first mirror 11 is disposed between the screen 5 and the concave mirror 6 along the optical path 22 connecting the screen 5 and the concave mirror 6, and the optical path 22 incident from the screen 5 in the first direction is defined as the first direction. The light reflecting means changes in a different second direction. Similarly, the second mirror 12 is disposed between the screen 5 and the concave mirror 6 along the optical path 22 connecting the screen 5 and the concave mirror 6, and the optical path 22 incident in the second direction from the screen 5 is different from the second direction. The light reflecting means changes in the third direction. In particular, in this embodiment, as shown in FIG. 6, the angle formed by the reflective surface of the first mirror 11 with the reflective surface of the second mirror is 90 degrees, and the angle formed by the reflective surface of the first mirror 11 with the first direction. Is 45 degrees, and the first mirror 11 and the second mirror 12 are arranged so that the angle between the reflection surface of the second mirror 12 and the third direction is 45 degrees. That is, in this embodiment, the first direction and the third direction are configured to be parallel to each other and opposite to each other.

  Moreover, the 1st mirror 11 and the 2nd mirror 12 are comprised so that movement is possible integrally along a 1st direction. Specifically, by driving the mirror drive motor 23 on the back side of the first mirror 11 and the second mirror 12, the first mirror 11 and the second mirror 12 are parallel to the first direction as shown in FIG. It is possible to move in the front-rear direction with respect to the correct direction.

  Then, by moving the first mirror 11 and the second mirror 12, the optical path length X of the optical path 22 connecting the screen 5 to the concave mirror 6 is changed. Specifically, as shown in FIG. 7, when the first mirror 11 and the second mirror 12 are moved in a direction approaching the screen 5, the optical path length X is shortened. On the other hand, if the first mirror 11 and the second mirror 12 are moved away from the screen 5, the optical path length X becomes longer. Specifically, the optical path length X is displaced by a distance that is twice the amount of movement of the first mirror 11 and the second mirror 12. That is, if the first mirror 11 and the second mirror 12 are moved 5 mm toward the screen 5, the optical path length X is shortened by 1 cm, and the first mirror 11 and the second mirror 12 are moved 3 mm away from the screen 5. If moved, the optical path length X becomes 6 mm longer. As a result of changing the optical path length X, it is possible to change the length of the generation distance L, which is the distance from the occupant 8 to the virtual image 9, as will be described later.

  In the present embodiment, as shown in FIG. 6, the first direction and the third direction are configured to be parallel and opposite to each other, but the first direction and the third direction are not necessarily parallel to each other and the reverse direction. There is no need to configure it to be. Specifically, if the first mirror 11 and the second mirror 12 are arranged so that the first direction and the third direction are different by 90 degrees or more, the first mirror 11 and the second mirror 12 are moved. The optical path length X of the optical path 22 connecting the screen 5 to the concave mirror 6 can be changed.

  In the present embodiment, the first mirror 11 and the second mirror 12 are configured to move in a direction parallel to the first direction. However, the first mirror 11 and the second mirror 12 are not necessarily moved in a direction parallel to the first direction. It is good also as a structure which moves to predetermined directions (for example, 5 degree | times and 10 degree | times) different directions. Even in this case, it is possible to change the optical path length X of the optical path 22 connecting the screen 5 to the concave mirror 6 by moving the first mirror 11 and the second mirror 12.

  The mirror drive motor 23 is a stepping motor. And HUD1 can control the mirror drive motor 23 based on the pulse signal transmitted from the control circuit part 16, and can position the position along the optical path 22 of the 1st mirror 11 and the 2nd mirror 12 appropriately. It becomes.

  In the HUD 1 of the present embodiment in which the screen 5 is disposed so as to be inclined with respect to the optical path 22 and the positions of the first mirror 11 and the second mirror 12 are movable as described above, The virtual image 9 of the image 26 projected on the screen 5 is generated as shown in FIG. 8 by changing the position of the image 26 projected and moving the first mirror 11 and the second mirror 12. The position (specifically, the generation distance L that is the distance from the occupant 8 to the virtual image 9) and the inclination angle of the virtual image 9 can be changed.

  Here, the generation distance L and the inclination angle of the virtual image 9 are the optical path length X of the optical path 22 connecting the screen 5 to the concave mirror 6 and the position where the image 26 is displayed on the screen 5, more specifically, the image 26 on the screen 5. Depends on the distance along the optical path 22 from the displayed position to the concave mirror. Therefore, in the present embodiment, the generation distance L and the inclination angle of the virtual image 9 are changed by moving the positions of the first mirror 11 and the second mirror 12 or changing the position where the image 26 is projected onto the inclined screen 5. It is possible to change. Specifically, when the position of the image 26 projected on the screen 5 is moved upward, or the first mirror 11 and the second mirror 12 are moved away from the screen 5, the image 26 is displayed on the screen 5. As a result, the distance along the optical path 22 from the raised position to the concave mirror becomes longer, and as a result, the generation distance L becomes longer (that is, the virtual image 9 can be viewed farther from the occupant 8). When the first mirror 11 and the second mirror 12 are moved away from the screen 5, the inclination angle φ of the virtual image 9 with respect to the ground surface becomes small (that is, the virtual image 9 becomes more parallel to the ground surface). ). On the other hand, when the position of the image 26 projected on the screen 5 is moved downward or when the first mirror 11 and the second mirror 12 are moved in a direction approaching the screen 5, the position where the image 26 is displayed on the screen 5. To the concave mirror 6 along the optical path 22 is shortened, and as a result, the generation distance L is shortened (that is, the virtual image 9 is viewed closer to the occupant 8). Further, when the first mirror 11 and the second mirror 12 are moved in a direction approaching the screen 5, the inclination angle φ of the virtual image 9 with respect to the ground surface increases (that is, the virtual image 9 becomes more perpendicular to the ground surface). ).

  Therefore, when the HUD 1 determines a position for generating the virtual image 9 (specifically, a generation distance L that is a distance from the occupant 8 to the virtual image 9), the HUD 1 generates the virtual image 9 at a position corresponding to the determined generation distance L. The optical path length X (that is, the position of the first mirror 11 and the second mirror 12) and the position at which the image 26 is projected on the screen 5 are determined, and then the first optical path length X is determined so as to be the determined optical path length X. The mirror 11 and the second mirror 12 are moved, and the position at which the image 26 is projected onto the screen 5 is also controlled. More specifically, a lower limit value and an upper limit value that can change the generation distance L are set by first determining the positions of the first mirror 11 and the second mirror 12, and then the image 26 is projected onto the screen 5. The generation distance L is configured to be changeable within the range from the set lower limit value to the upper limit value by appropriately changing the position to be performed.

  Since the generation distance L depends on the distance along the optical path 22 from the position where the image 26 is displayed on the screen 5 to the concave mirror as described above, in particular, the position of the image 26 displayed on the screen 5 is It is displaced when the distance from the concave mirror 6 is displaced in the direction in which the distance changes (that is, the short side direction of the screen 5). Further, the displacement amount of the generation distance L with respect to the displacement amount of the display position of the image 26 differs depending on the distance from the position where the image 26 is displayed to the concave mirror 6. That is, as the position where the image 26 is displayed is farther from the concave mirror 6 (that is, when the optical path length X is longer or when the image 26 is projected above the screen 5), the displacement amount of the generation distance L with respect to the displacement amount of the display position of the image 26 becomes smaller. growing. That is, when the optical path length X is short or below the screen 5, the generated distance L does not change greatly even if the display position of the image 26 is displaced. However, when the optical path length X is long or above the screen 5, Even when the display position is slightly displaced, the generation distance L is greatly displaced.

  Further, the range in which the generation distance L can be changed and the range in which the tilt angle φ of the virtual image 9 can be changed are such that the tilt angle θ of the screen 5 and the first mirror 11 and the second mirror 12 can be moved. Determined by range. In particular, in the present embodiment, when the first mirror 11 and the second mirror 12 are moved to the most screen 5 side, the inclination angle φ is an angle very close to 90 degrees, regardless of the position where the image 26 is projected. The generation distance L is designed to be approximately 2.5 m. On the other hand, in the state where the first mirror 11 and the second mirror 12 are moved to the position farthest from the screen 5, the inclination angle φ is an angle close to 0 degrees and is projected to the lowermost part of the projection area 21. The generation distance L of the lower end of the virtual image 9 of the image 26 is 15 m, and the generation distance L of the upper end of the virtual image 9 of the image 26 projected above the projection area 21 is 40 m. That is, when the image 26 straddling from the lower end to the upper end of the projection area 21 is displayed, the virtual image 9 straddling the section whose distance from the occupant 8 is 15 m to 40 m is generated.

  Here, the image 26 projected on the screen 5 is reflected by the concave mirror 6, but is also reflected by the first mirror 11, the second mirror 12, and the reflecting mirror 13, so that the generated virtual image 9 is the screen. The image projected on 5 and the top / bottom / left / right are non-inverted images. That is, the image 26 projected above the screen 5, the virtual image 9 generated based on the image 26 is also visually recognized from the occupant 8 in the vertical direction, and the image 26 projected below the screen 5 is the image. 26 is also visually recognized from the passenger 8 on the lower side in the vertical direction. Therefore, the virtual image 9 generated at a position far from the occupant 8 can be seen upward from the occupant 8. Here, when the vehicle occupant 8 visually recognizes the front environment through the front window 7, basically, the one located farther away looks higher. Therefore, it becomes possible to make the superimposed display of the virtual image 9 and the front environment easy to see by making the front environment visible by tilting the screen 5 correspond to the virtual image 9.

  Further, since the virtual image 9 having a longer generation distance L has a smaller inclination angle φ, for example, guidance is provided by causing the occupant 8 to visually recognize the vehicle by superimposing it on the surrounding environment such as an arrow for guiding the traveling direction of the vehicle or a warning displayed on the road surface. When generating the virtual image 9 to be performed, the virtual image 9 is generated along the road surface (the ground surface) as much as possible by setting the generation distance L long (for example, 20 m). As a result, the generated virtual image 9 can be appropriately superimposed on the surrounding environment. On the other hand, for example, when generating the virtual image 9 for guidance by causing the occupant 8 to visually recognize the vehicle without superimposing it on the surrounding environment such as the current vehicle speed, TV screen, and map image, the generation distance L is set short ( For example, the virtual image 9 is generated as perpendicular to the road surface (ground surface) as possible. As a result, it is possible to generate a virtual image 9 that is easy to see for the user.

  On the other hand, the reflection mirror 13 changes the optical path 22 in the HUD 1 by further reflecting the light from the light source 18 reflected by the first mirror 11 and the second mirror 12 in the direction of the concave mirror 6 as shown in FIG. It is a light reflecting means.

  The cover glass 15 is a transmissive plate-like member disposed on the upper surface of the HUD 1. The image displayed on the screen 5 is reflected by the concave mirror 6 and is made visible to the occupant 8 through the cover glass 15. Note that a Fresnel lens may be used as the cover glass 15. When a Fresnel lens is used as the cover glass 15, a flat mirror can be used instead of the concave mirror 6.

  The control circuit unit 16 is an electronic control unit that controls the entire HUD 1. Here, FIG. 10 is a block diagram showing a configuration of the HUD 1 according to the present embodiment.

  As shown in FIG. 10, the control circuit unit 16 includes a CPU 31 as an arithmetic device and a control device, a RAM 32 used as a working memory when the CPU 31 performs various arithmetic processes, a control program, and a generation distance described later. An ROM 33 in which a change processing program (see FIG. 11) is recorded, an internal storage device such as a flash memory 34 for storing a program read from the ROM 33 and a position setting table to be described later are provided. The control circuit unit 16 is connected to the projector 4 and the mirror drive motor 23, respectively, and controls the drive of the projector 4 and various motors.

  The CAN (controller area network) interface 17 is an interface for inputting / outputting data to / from CAN, which is a vehicle-mounted network standard that performs multiplex communication between various vehicle-mounted devices and vehicle equipment control devices installed in the vehicle. It is. The HUD 1 is connected to a control device (for example, the navigation device 48, the AV device 49, etc.) of various vehicle-mounted devices and vehicle equipment via the CAN so as to be able to communicate with each other. Thereby, the HUD 1 is configured to be able to project information acquired from the navigation device 48, the AV device 49, and the like. Also, traffic information such as VICS (registered trademark) information and probe information can be acquired from the navigation device 48.

  Next, a generation distance change processing program executed by the CPU 31 in the HUD 1 having the above configuration will be described with reference to FIG. FIG. 11 is a flowchart of the generated distance change processing program according to this embodiment. Here, the generated distance change processing program is executed after the ACC power supply of the vehicle is turned on, and changes the distance from the occupant 8 of the virtual image 9 to be visually recognized by the occupant 8 of the vehicle to an appropriate distance according to the surrounding situation. It is a program. The programs shown in the flowcharts of FIGS. 11, 13, 15, 18, and 19 below are stored in the RAM 32 and the ROM 33 provided in the HUD 1, and are executed by the CPU 31.

  In this embodiment, in the normal state after the ACC power supply of the vehicle is turned on, the positions of the first mirror 11 and the second mirror 12 are set to the “reference position”. Here, the “reference position” is the generation distance L of the lower end of the virtual image 9 generated based on the video 26 projected to the lowermost side of the projection area 21 (that is, the display position of the video 26 in the projection area 21). The lower limit of the changeable range of the generation distance L based on the optical path length X is 15 m. For example, the position farthest from the screen 5 is the “reference position”. As described above, since the screen 5 is arranged to be inclined with respect to the optical path 22, when the positions of the first mirror 11 and the second mirror 12 are set to the “reference position”, the projected area 21. The generation distance L of the upper end of the virtual image 9 generated based on the image 26 projected on the uppermost side (that is, the upper limit of the changeable range of the generation distance L based on the display position of the image 26 in the projection area 21) is It becomes 40m longer than 15m. That is, the virtual image 9 can be generated when the distance from the vehicle occupant 8 is in the range of 15 m to 40 m.

  In the generation distance change processing program executed after the positions of the first mirror 11 and the second mirror 12 are set to the “reference position”, in step (hereinafter abbreviated as S) 1, the CPU 31 moves the projector 4 to the projector 4. And the projector 4 starts projecting an image onto the screen 5. The video projected by the projector 4 includes information related to the vehicle 2 and various information used for assisting the driving of the occupant 8. For example, a warning for an obstacle (another vehicle or a pedestrian), a guidance route (scheduled travel route) set by the navigation device 48, guidance information based on the guidance route (such as an arrow indicating the traveling direction of the vehicle), and a warning displayed on the road surface (Notes of rear-end collision, speed limit, etc.), current vehicle speed, information signs, map images, traffic information, news, weather forecast, time, connected smartphone screen, TV screen, etc. In particular, in the present embodiment, an arrow indicating the traveling direction of the vehicle, which is guidance information based on the guidance route set by the navigation device 48, is output.

  As a result, for example, when a guidance route is set in the navigation device 48, and there is no intersection to be turned right or left in front of the vehicle in the traveling direction, the vehicle travels straight ahead in the traveling direction of the vehicle as shown in FIG. A virtual image 9 of an arrow indicating the direction is generated. In the present embodiment, the virtual image 9 is generated so that the virtual image 9 indicated by an arrow is positioned on the ground, and more specifically, the lower end of the virtual image 9 is positioned on the ground. When an intersection to be turned right or left approaches in front of the traveling direction of the vehicle, a virtual image 9 of an arrow indicating a right / left turn is generated instead of an arrow indicating a straight traveling direction. Note that the position within the range of 15 m to 40 m at which the virtual image 9 is generated can be set in detail based on the position at which the video 26 is projected onto the projection area 21. Basically, the image 26 is projected so as to generate the virtual image 9 at a position where the distance from the passenger 8 to the lower end of the virtual image 9 is 20 m (hereinafter referred to as a standard position). However, as described later, when there is a traffic jam section ahead of the traveling direction of the vehicle, control is performed so that the position where the virtual image 9 is generated is changed from the standard position (S4, S5). The distance from the occupant 8 to the virtual image 9 is basically controlled by changing the projection (display) position of the video 26 in the projection area 21, but the changeable range based on the projection position of the video 26 ( For example, when the first mirror 11 and the second mirror 12 are in the reference position, the position of the first mirror 11 and the second mirror 12 is moved when it is necessary to change the distance beyond 15 m to 40 m). Also do.

  The “standard position” may be changed according to the road type of the road on which the vehicle travels. Specifically, it is desirable to set a longer distance from the occupant 8 to the virtual image 9 when the road type is a high standard road than when the road type is a general road. For example, in the case of a general road, the position where the distance from the occupant 8 to the lower end of the virtual image 9 is 20 m is set as the standard position, and from the occupant 8 to the lower end of the virtual image 9 on a high-standard road such as an automobile-only road or a highway. The position where the distance is 30 m may be the standard position.

  Next, in S2, the CPU 31 executes a congestion determination process (FIG. 13) described later. The traffic jam determination process is a process for determining the traffic jam situation on the road ahead in the traveling direction along the planned travel route of the vehicle, as will be described later.

  Subsequently, in S3, the CPU 31 determines whether or not the “congestion flag” is turned on. Note that the “congestion flag” is stored in the RAM 32 or the like, and it is determined in the traffic congestion determination process of S2 that there is a road section with a congestion level of “congested” or “congested” ahead in the traveling direction along the planned travel route of the vehicle. It is turned on when

  If it is determined that the “congestion flag” is ON (S3: YES), that is, there is a road section with a congestion level of “congested” or “congested” ahead in the traveling direction along the planned travel route of the vehicle. If so, the process proceeds to S4. On the other hand, when it is determined that the “congestion flag” is OFF (S3: NO), that is, a road section with a congestion level of “congested” or “congested” ahead in the traveling direction along the planned travel route of the vehicle. If no exists, the process returns to S2. As a result, the virtual image 9 of the arrow indicating the traveling direction of the vehicle is continuously generated at the standard position (position where the distance from the occupant 8 to the lower end of the virtual image 9 is 20 m) (FIG. 12). After that, the generation position of the virtual image 9 basically does not change until the congestion section approaches, no matter how the vehicle speed changes. That is, the generation distance L is not dependent on the vehicle speed.

  In S4, the CPU 31 executes a generation distance control process (FIG. 15) described later. The generation distance control process is a process for controlling the generation distance L, which is the distance from the occupant 8 to the virtual image 9, according to the traffic congestion status, road type, vehicle speed, etc. in the forward direction of the vehicle, as will be described later. It is.

  Next, in S5, the CPU 31 executes a generation distance changing process (FIG. 18) based on the vehicle speed described later. The generation distance changing process based on the vehicle speed is a process for controlling the generation distance L, which is a distance from the occupant 8 to the virtual image 9, in accordance with a change in the vehicle speed of the vehicle, as will be described later.

  Subsequently, in S6, the CPU 31 executes a control release determination process (FIG. 19) described later. The control release determination process is a process for determining whether or not to continue the control of the generation distance L (S4, S5) based on the traffic congestion state, the road type, and the vehicle speed of the vehicle, as will be described later. is there.

  Thereafter, in S7, the CPU 31 determines whether or not the “control release flag” is ON. The “control release flag” is stored in the RAM 32 or the like, and the control of the generation distance L (S4, S5) based on the traffic congestion state, the road type, and the vehicle speed of the vehicle is terminated in the control release determination process of S6. It is turned on when it is determined that it should be.

  If it is determined that the “control release flag” is ON (S7: YES), that is, the control of the generation distance L based on the traffic congestion status, road type, and vehicle speed should be terminated. If it is determined, the process proceeds to S8. On the other hand, when it is determined that the “control release flag” is OFF (S7: NO), that is, the control of the generation distance L based on the traffic congestion status, the road type, and the vehicle speed is continued. If it is determined that it should be performed, the process returns to S5. Thereafter, the control (S4, S5) of the generation distance L based on the traffic congestion situation, the road type, and the vehicle speed of the vehicle is continuously performed.

  In S8, the CPU 31 returns the generation position of the virtual image 9 changed in S4 and S5 to the standard position before the change.

  In S8, when the current positions of the first mirror 11 and the second mirror 12 have been moved from the “reference position”, the CPU 31 drives the mirror drive motor 23 to drive the first mirror 11 and the second mirror 11. The mirror 12 is moved to the “reference position”. When the projection position of the image 26 on the screen 5 is changed, a control signal is transmitted to the projector 4 to return the projection position of the image 26 to the original position. As a result, the virtual image 9 of the arrow indicating the traveling direction of the vehicle is generated again at the standard position (position where the distance from the passenger 8 to the lower end of the virtual image 9 is 20 m) (FIG. 12). After that, until the traffic jam section approaches again, the generation position of the virtual image 9 basically does not change no matter how the vehicle speed changes. That is, the generation distance L is not dependent on the vehicle speed.

  Next, sub-processing of the congestion determination process executed in S2 will be described with reference to FIG. FIG. 13 is a flowchart of a sub-processing program for traffic jam determination processing.

  First, in S11, the CPU 31 obtains traffic information that specifically defines the degree of traffic congestion on the road from the server of the VICS center, which is an external server. The traffic information may be acquired directly from the VICS center by a communication device provided in the HUD 1 or may be acquired via the navigation device 48. Here, the VICS center detects the degree of traffic jam based on the road type and the average vehicle speed detected by the roadside device installed on the road. Specifically, as shown in FIG. 14, the degree of congestion is specified as one of “congested”, “congested”, and “smooth”. For example, on a city highway, a section where the average vehicle speed of the vehicle is 30 km / h is determined as “congested”, and a section where the average vehicle speed is 15 km / h is determined as “congested”. The traffic jam information may be acquired from a server other than the VICS center (for example, a probe center).

  Next, in S12, the CPU 31 obtains a guide route (scheduled travel route of the vehicle) currently set by the navigation device 48 from the navigation device 48 via the CAN.

  Subsequently, in S13, the CPU 31 determines whether or not there is a road section in which the degree of congestion is determined as “congested” or “congested” within a predetermined distance (for example, within 1 km) ahead of the traveling direction along the planned travel route of the vehicle. To determine.

  When it is determined that there is a road section in which the degree of congestion is determined as “congested” or “congested” within a predetermined distance ahead in the traveling direction along the planned travel route of the vehicle (S13: YES), The process proceeds to S14. On the other hand, when it is determined that there is no road section in which the degree of congestion is determined as “congested” or “congested” within a predetermined distance ahead in the traveling direction along the planned travel route of the vehicle (S13: NO). Shifts to S3 while keeping the traffic jam flag OFF.

  In S14, the CPU 31 reads the traffic jam flag from the RAM 32 and sets it to ON. Thereafter, the traffic jam flag is stored again in the RAM 32, and the process proceeds to S3. The traffic jam flag is set to OFF in the initial state.

  Next, the sub-process of the generation distance control process executed in S4 will be described with reference to FIG. FIG. 15 is a flowchart of a sub-processing program for the generation distance control process.

  First, in S21, the CPU 31 acquires a start point (hereinafter referred to as a “congestion start point”) of a road section in which the degree of traffic congestion determined to be ahead in the vehicle traveling direction in S13 is “congested” or “congested”. If there are a plurality of “congested” or “congested” road sections ahead of the traveling direction of the vehicle, the traffic start point of the road section closest to the vehicle along the planned travel route is acquired.

  Next, in S <b> 22, the CPU 31 identifies a point (hereinafter referred to as a control start point) where the control of the generation distance L based on the traffic congestion state of the road and the vehicle speed is started. Specifically, as shown in FIG. 16, a point a predetermined distance (for example, 100 m) before the traffic jam start point acquired in S21 along the planned travel route is specified as the control start point. The predetermined distance may be changed according to the vehicle speed and the road type.

  Subsequently, in S23, the CPU 31 acquires from the navigation device 48 based on the detection result of the current position of the vehicle via the CAN. Note that it is desirable to specify the current position of the vehicle in detail using a high-precision location technology. Here, the high-accuracy location technology detects the white line and road surface paint information captured from the camera behind the vehicle by image recognition, and further compares the white line and road surface paint information with a previously stored map information DB, thereby driving the vehicle. This is a technology that makes it possible to detect lanes and highly accurate vehicle positions. The details of the high-accuracy location technology are already known and will be omitted.

  Thereafter, in S24, the CPU 31 calculates a road distance along the planned travel route from the current position of the vehicle detected in S23 to the control start point specified in S22.

  Next, in S25, the CPU 31 determines whether or not the host vehicle has reached the control start point, that is, whether or not the distance calculated in S24 has become zero.

  When it is determined that the host vehicle has reached the control start point, that is, the distance calculated in S24 has become 0 (S25: YES), the process proceeds to S26. On the other hand, when it is determined that the vehicle has not reached the control start point, that is, the distance calculated in S24 is not 0 (S25: NO), the process returns to S23.

  In S26, CPU31 acquires the present vehicle speed of the own vehicle using the vehicle speed sensor installed in the vehicle.

  Next, in S27, the CPU 31 acquires the road type of the road section in which the degree of traffic congestion determined to be ahead in the traveling direction of the vehicle in S13 is “congested” or “congested”. In the following embodiments, three types of roads are defined as “general road”, “urban highway”, and “highway”, and road sections where the degree of congestion is determined as “congested” or “crowded” are described above. A description will be given assuming that it belongs to one of the three types.

  Subsequently, in S28, the CPU 31 determines that the current situation is most appropriate based on the traffic jam information acquired in S11, the current vehicle speed of the vehicle acquired in S26, and the road type acquired in S27. The value of the generation distance L (hereinafter referred to as the optimal generation distance) is determined.

Details of the optimum generation distance determination process in S28 will be described below with reference to FIG.
As shown in FIG. 17, the HUD 1 according to the present embodiment stores a table in which the degree of congestion, road type, vehicle speed, and optimum generation distance are associated with each other in the flash memory 34. In S28, the CPU 31 reads the table shown in FIG. 17 from the flash memory 34 and determines the optimum generation distance. For example, when the congestion degree of the road section ahead of the traveling direction of the vehicle is “congested”, the road type is “general road”, and the current vehicle speed of the vehicle is “15 km”, the optimum generation distance is 10 m is determined. If the other conditions are the same, the optimum generation distance becomes shorter in the order of the road type: highway, urban highway, and general road. That is, the optimum generation distance is shorter on the general road than on the high standard road. Further, if the other conditions are the same, the optimum generation distance becomes shorter as the current vehicle speed of the vehicle is slower. Furthermore, if the other conditions are the same, the optimum generation distance becomes shorter as the degree of congestion is higher (that is, the section of “congestion” than “congestion”). In other words, the optimum generation distance is determined to be shorter in a situation where the distance from the preceding vehicle is likely to be clogged. As a result, it is possible to prevent the generated virtual image 9 from being overlapped with the preceding vehicle and embedded in the preceding vehicle.

  Thereafter, in S29, the CPU 31 controls the projection position of the image 26 on the screen 5 and the positions of the first mirror 11 and the second mirror 12 so that the generation distance L of the virtual image 9 becomes the optimum generation distance determined in S28. To do.

  Specifically, the optimum generation distance is within a changeable range of the generation distance L based on the current positions of the first mirror 11 and the second mirror 12 (for example, when the first mirror 11 and the second mirror 12 are at the reference position). 15 m to 40 m), a control signal is transmitted to the projector 4 and the position at which the image 26 is projected onto the screen 5 is changed so that the generation distance L becomes the optimum generation distance. To do. On the other hand, when the optimal generation distance is not within the changeable range of the generation distance L based on the current positions of the first mirror 11 and the second mirror 12, the mirror drive motor 23 is driven to The position of the second mirror 12 is changed from the “reference position”. Specifically, when the optimum generation distance is shorter than the lower limit of the changeable range of the generation distance L based on the current positions of the first mirror 11 and the second mirror 12, the optical path 22 connecting the screen 5 to the concave mirror 6. The positions of the first mirror 11 and the second mirror 12 are moved so that the optical path length X becomes shorter. On the other hand, when the optimum generation distance is longer than the upper limit of the changeable range of the generation distance L based on the current positions of the first mirror 11 and the second mirror 12, the optical path length of the optical path 22 connecting the screen 5 to the concave mirror 6. The positions of the first mirror 11 and the second mirror 12 are moved so that X becomes longer.

Below, the detail of the movement process of the 1st mirror 11 and the 2nd mirror 12 is demonstrated.
First, the CPU 31 reads the position setting table from the flash memory 34, and acquires the positions (target movement positions) of the first mirror 11 and the second mirror 12 that include the optimum generation distance in the changeable range of the generation distance L. The position setting table is for generating the virtual image 9 in the range of the generation distance L for each range of the generation distance L that can be set (in this embodiment, 0.5 m unit between 2.5 m and 40 m). The positions of the first mirror 11 and the second mirror 12 are defined. Subsequently, the CPU 31 determines the drive amount (number of pulses) of the mirror drive motor 23 required to move the first mirror 11 and the second mirror 12 to the target movement position. Thereafter, the CPU 31 transmits to the mirror drive motor 23 a pulse signal for driving the mirror drive motor 23 by the determined drive amount. Then, the mirror drive motor 23 that has received the pulse signal drives based on the received pulse signal. As a result, the positions of the first mirror 11 and the second mirror 12 that can generate the virtual image 9 at a position separated from the vehicle occupant 8 by the optimum generation distance are obtained. Thereafter, the process proceeds to S5.

  Next, the sub-process of the generation distance changing process based on the vehicle speed executed in S5 will be described with reference to FIG. FIG. 18 is a flowchart of a sub-processing program for the generation distance changing process based on the vehicle speed.

  First, in S31, CPU31 acquires the present vehicle speed of the own vehicle using the vehicle speed sensor installed in the vehicle.

  Next, in S32, the CPU 31 determines whether or not the vehicle speed acquired in S31 is decelerated from the vehicle speed used for determining the most recent optimum generation distance (S28, S34).

  And when it determines with the vehicle speed acquired by said S31 decelerating from the vehicle speed used for the determination of the latest optimal production | generation distance (S32: YES), it transfers to S33. On the other hand, if it is determined that the vehicle speed acquired in S31 is the same as or faster than the vehicle speed used to determine the most recent optimum generation distance (S32: NO), the generation distance L, that is, the virtual image 9 The process proceeds to S6 without changing the generation position.

  In S33, the CPU 31 obtains again the road type of the road section in which the degree of congestion determined to be ahead in the traveling direction of the vehicle in S13 is “congested” or “congested”.

  Subsequently, in S34, the CPU 31 determines a new optimum based on the changed vehicle speed based on the traffic jam information acquired in S11, the current vehicle speed of the vehicle acquired in S31, and the road type acquired in S33. Determine the generation distance. The details of the process for determining the optimum generation distance in S34 are the same as in S28, and a description thereof will be omitted.

  Thereafter, in S35, the CPU 31 controls the projection position of the image 26 on the screen 5 and the positions of the first mirror 11 and the second mirror 12 so that the generation distance L of the virtual image 9 becomes the optimum generation distance determined in S34. To do. Note that the details of the process related to the change of the generation distance L in S35 are the same as in S29, and a description thereof will be omitted. Thereafter, the process proceeds to S6.

  And as a result of performing the process of said S31-S35, even if it is a case where the vehicle speed of a vehicle changes after determination of the optimal generation distance, the generation distance L is changed according to the vehicle speed after a change, and a virtual image is set to an optimal position. 9 can be generated. In the present embodiment, the generation distance L is changed only when the vehicle speed of the vehicle is decelerated, and the generation distance L is not changed even when the vehicle speed increases. That is, the control of the generation distance L based on the vehicle speed of the vehicle after the optimal generation distance is once determined is to displace the generation distance L only in the direction in which the generation distance L becomes shorter. As a result, the generation distance L is changed only in a necessary situation (for example, a situation where it is necessary to avoid overlap between the preceding vehicle and the virtual image), and the number of times the generation distance is changed can be reduced. .

  Next, the sub-process of the control release determination process executed in S6 will be described with reference to FIG. FIG. 19 is a flowchart of a sub-processing program for the control release determination process.

  First, in S41, the CPU 31 acquires from the navigation device 48 based on the detection result of the current position of the vehicle via the CAN.

  Next, in S42, the CPU 31 determines that the degree of congestion determined to be ahead in the traveling direction of the vehicle in S13 based on the congestion information acquired in S11 and the current position of the vehicle acquired in S41 is “congestion”. It is determined whether or not the vehicle has passed through the end point of the road section "" or "congested".

  Then, when it is determined that the vehicle has passed the end point of the “congested” or “congested” road section (S42: YES), the control of the generation distance L based on the traffic congestion status, the road type, and the vehicle speed of the vehicle. Is determined to end, and the process proceeds to S46. On the other hand, when it is determined that the vehicle does not pass through the end point of the “congested” or “congested” road section (S42: NO), the process proceeds to S43.

  In S43, the CPU 31 acquires the current vehicle speed of the host vehicle using a vehicle speed sensor installed in the vehicle.

  In S44, the CPU 31 obtains the upper limit of the defined speed of the congestion degree determined in the road section for the road section whose congestion degree is determined to be ahead in the traveling direction of the vehicle in S13 and is “congested” or “congested”. To do. For example, when the road section is “congested”, it is an upper limit speed for determining “congested”, and as shown in FIG. 14, a general road is 10 km / h, an urban highway is 20 km / h, The expressway is 40 km / h. On the other hand, when the road section is “congested”, it is the upper limit speed for determining “congested”. As shown in FIG. 14, a general road is 20 km / h, an urban highway is 40 km / h, The expressway will be 60 km / h.

  Next, in S45, the CPU 31 determines whether or not the current vehicle speed of the vehicle is faster than the upper limit of the traffic speed definition speed acquired in S44.

  If it is determined that the current vehicle speed of the vehicle is faster than the upper limit of the traffic speed definition speed acquired in S44 (S45: YES), “congestion” and “congestion” have already been resolved, It is determined that the control of the generation distance L based on the traffic congestion situation, the road type, and the vehicle speed of the vehicle should be terminated, and the process proceeds to S46. On the other hand, when it is determined that the current vehicle speed of the vehicle is the same as or slower than the upper limit of the congestion speed definition speed acquired in S44 (S45: NO), the traffic congestion status of the road, the road type, and the vehicle speed of the vehicle It is determined that the control of the generation distance L based on the above should be continued, and the process proceeds to S7 while the control release flag remains OFF.

  In S46, the CPU 31 reads the control release flag from the RAM 32 and sets it to ON. Thereafter, the control release flag is stored again in the RAM 32, and the process proceeds to S7. Note that the control release flag is set to OFF in the initial state.

  As described above in detail, according to the HUD 1 according to the present embodiment, an image is projected from the projector 4 onto the screen 5, and the image projected onto the screen 5 is reflected on the front window 7 of the vehicle 2 so as to occupy the vehicle. 8, the virtual image of the image | video which the passenger | crew 8 of a vehicle visually recognizes is produced | generated. Further, the HUD 1 acquires traffic jam information ahead of the traveling direction of the vehicle from the VICS center that is an external server (S11), and based on the acquired traffic jam information, a generation distance L that is a distance from the vehicle occupant 8 to the virtual image 9 (S5, S6). As a result, since the distance from the occupant 8 to the virtual image 9 is controlled based on the wider area information acquired from the external server, the distance from the occupant 8 to the virtual image 9 does not change frequently, It becomes possible to generate a virtual image 9 that is easily visible to the occupant 8 at an appropriate position in consideration of the situation. Further, it is possible to reduce the processing burden on the apparatus side related to the control of the generation position of the virtual image 9 as compared with the conventional case.

Note that the present invention is not limited to the above-described embodiment, and various improvements and modifications can be made without departing from the scope of the present invention.
For example, in the present embodiment, the virtual image is generated in front of the front window 7 of the vehicle 2 by the HUD 1, but the virtual image may be generated in front of a window other than the front window 7. In addition, the object to be reflected by the HUD 1 may be a visor (combiner) installed around the front window 7 instead of the front window 7 itself.

  In the present embodiment, the HUD 1 is installed on the vehicle 2. However, the HUD 1 may be installed on a moving body other than the vehicle 2. For example, it can be installed on a ship or an aircraft. Moreover, you may install in the ride type attraction installed in an amusement facility. In that case, a virtual image can be generated around the ride so that the rider can visually recognize the virtual image.

  In the present embodiment, traffic jam information is acquired as wide area traffic information, and the generation distance L is controlled based on the acquired traffic information. Traffic information other than the traffic jam information (for example, accident information, construction information, etc.) The generation distance L may be controlled based on the lane regulation information. For example, when there is an accident, construction, or lane regulation section ahead of the vehicle traveling direction, it is expected that the distance from the vehicle ahead will be narrowed, so control the generation distance L to be shorter than usual. Is desirable. The external server that acquires the traffic information may be a server other than the VICS center.

  In the present embodiment, the first mirror 11 and the second mirror 12 are integrally moved along the optical path, so that the optical path length X of the optical path 22 connecting the screen 5 to the concave mirror 6 is changed. The first mirror 11 and the second mirror 12 may be fixed, and the optical path length X may be changed by moving the screen 5 and the concave mirror 6 along the optical path. In addition, the first mirror 11 and the second mirror 12 may be configured to be driven by different driving sources as long as the first mirror 11 and the second mirror 12 are configured to move together.

  In the present embodiment, the first mirror 11 and the second mirror 12 are configured to move in a direction parallel to the first direction. However, the first mirror 11 and the second mirror 12 are not necessarily moved in a direction parallel to the first direction. It is good also as a structure which moves to predetermined directions (for example, 5 degree | times and 10 degree | times) different directions. Even in this case, it is possible to change the optical path length X of the optical path 22 connecting the screen 5 to the concave mirror 6 by moving the first mirror 11 and the second mirror 12.

  In the present embodiment, the screen 5 is disposed so as to be inclined with respect to the optical path 22 of the light source 18 connecting the screen 5 and the concave mirror 6, but is disposed so as to be perpendicular to the optical path 22. Also good. In that case, the generation distance L is changed only by moving the first mirror 11 and the second mirror 12.

  In the present embodiment, the virtual image 9 is configured to generate an arrow indicating the traveling direction of the vehicle. However, a warning for an obstacle (another vehicle or a pedestrian), a warning displayed on the road surface (attention for rear-end collision, speed limit, etc.) Or the like may be generated as a virtual image 9.

  In this embodiment, a laser scanning projector that does not require a projection lens is used, but a projector other than the laser scanning projector (for example, a DLP projector, a liquid crystal projector, or an LCOS projector) may be used. Further, instead of the projector 4 and the screen 5, a liquid crystal display, an organic EL display, or the like may be used as a means for displaying an image to be visually recognized by the passenger 8.

  In the present embodiment, the CPU 31 of the HUD 1 is configured to execute each step of the generated distance change processing program (FIG. 11). However, an on-vehicle device (for example, the navigation device 48) other than the HUD 1 or an ECU that controls the vehicle is used. It is good also as a structure which performs a one part or all process.

  Moreover, although the embodiment which actualized the virtual image display device according to the present invention has been described above, the virtual image display device can also have the following configuration, and in that case, the following effects can be obtained.

For example, the first configuration is as follows.
A video display surface for displaying video; a virtual image generating means for generating a virtual image of the video by allowing a user to visually recognize the video displayed on the video display surface; and traffic information ahead of the user in the traveling direction from an external server And a generation distance control unit that controls a generation distance that is a distance from the user to the virtual image based on the traffic information acquired by the traffic information acquisition unit. And
According to the virtual image display device having the above configuration, since the distance from the user to the virtual image is controlled based on the wider area information acquired from the external server, the distance from the user to the virtual image does not change frequently, It becomes possible to generate a virtual image that is easy for the user to visually recognize at an appropriate position in consideration of the situation. Further, it is possible to reduce the processing load on the apparatus side related to the control of the virtual image generation position as compared with the conventional case.

The second configuration is as follows.
The speed acquisition means for acquiring the movement speed of the user and the generation distance control means control the generation distance based on the movement speed of the user.
According to the virtual image display device having the above-described configuration, the distance to the obstacle (for example, the vehicle ahead) in the user's line of sight is predicted based on the moving speed of the user, and a virtual image is generated at an appropriate position that does not overlap with the obstacle. It becomes possible to do.

The third configuration is as follows.
The generation distance control means controls the generation distance to be shorter as the moving speed of the user is slower.
According to the virtual image display device having the above configuration, when the moving speed of the user is slow, it is predicted that the distance to the obstacle (for example, the vehicle ahead) in the user's line of sight is shortened, and the generation distance is shortened. It becomes possible to generate a virtual image at an appropriate position that does not overlap with an obstacle.

The fourth configuration is as follows.
The generation distance control means is characterized in that the generation distance control based on the moving speed of the user displaces the generation distance only in a direction in which the generation distance becomes shorter.
According to the virtual image display device having the above-described configuration, it is possible to reduce the number of times the generation distance is changed by changing the generation distance only in a necessary situation. As a result, the distance from the user to the virtual image does not change frequently, and the processing burden on the apparatus side can be reduced.

The fifth configuration is as follows.
The traffic information acquisition means acquires a traffic congestion situation on the road ahead of the user in the traveling direction as the traffic information, and the generation distance control means indicates that the traffic congestion degree on the road ahead of the user traveling direction is congestion or traffic jam. In this case, the generation distance is controlled based on the moving speed of the user. When the degree of congestion on the road ahead in the traveling direction of the user is smooth, the distance that does not depend on the moving speed of the user is generated. It is characterized by a distance.
According to the virtual image display device having the above-described configuration, in a situation where there is a high possibility that the distance to an obstacle (for example, a vehicle ahead) in the user's line-of-sight direction is likely to be short, the user's line-of-sight direction is based on the moving speed of the user. It is possible to predict the distance to the obstacle (for example, the vehicle ahead) and generate a virtual image at an appropriate position that does not overlap with the obstacle. On the other hand, in a situation where the distance to the obstacle in the user's line of sight is unlikely to be short, the distance from the user to the virtual image is reduced by not changing the generation distance based on the moving speed of the user. The processing load on the apparatus side can be reduced without being changed unnecessarily.

The sixth configuration is as follows.
The generation distance control unit includes a position acquisition unit configured to acquire the position of the user, and the generation distance control unit includes a movement speed of the user until the position of the user passes through an end point of a road section where the degree of congestion is congested or congested. The generation distance is controlled based on the user's position, and after the user's position passes the end point of a road section where the degree of congestion is congested or congested, a distance that does not depend on the moving speed of the user is set as the generation distance. It is characterized by.
According to the virtual image display device having the above-described configuration, in a situation where there is a high possibility that the distance to an obstacle (for example, a vehicle ahead) in the user's line-of-sight direction is likely to be short, the user's line-of-sight direction is based on the moving speed of the user. It is possible to predict the distance to the obstacle (for example, the vehicle ahead) and generate a virtual image at an appropriate position that does not overlap with the obstacle. On the other hand, in a situation where the distance to the obstacle in the user's line of sight is unlikely to be short, the distance from the user to the virtual image is reduced by not changing the generation distance based on the moving speed of the user. The processing load on the apparatus side can be reduced without being changed unnecessarily.

The seventh configuration is as follows.
The generation distance control means determines whether or not the user's position is at a speed corresponding to the congestion degree of the road section when the user's position moves on a road section where the congestion degree is congested or congested. If it is determined that the moving speed of the user is not a speed corresponding to the degree of congestion of the road section, a distance that does not depend on the moving speed of the user is set as the generated distance.
According to the virtual image display device having the above-described configuration, it is possible to determine based on the moving speed of the user whether the congestion or traffic congestion has been eliminated. And when it determines with the condition of congestion and traffic congestion having been eliminated, the distance from a user to a virtual image is unnecessarily changed by setting it as the structure which does not change the generation distance based on a user's moving speed. It is also possible to reduce the processing load on the apparatus side.

The eighth configuration is as follows.
The road type acquisition means for acquiring the road type of the road from which the traffic information has been acquired, and the generation distance control means control the generation distance based on the road type of the road from which the road information has been acquired. .
According to the virtual image display device having the above-described configuration, an appropriate position that predicts an interval to an obstacle (for example, a vehicle ahead) in the user's line of sight based on the road type of the road on which the user moves and does not overlap with the obstacle. It is possible to generate a virtual image.

The ninth configuration is as follows.
The generation distance control means controls the generation distance to be shorter when the road type of the road from which the road information is acquired is a general road than when it is a high-standard road.
According to the virtual image display device having the above configuration, when the road type of the road on which the user moves is a general road, it is predicted that the interval to an obstacle (for example, a vehicle ahead) in the user's line of sight is shortened, By shortening the generation distance, it is possible to generate a virtual image at an appropriate position that does not overlap with an obstacle.

The tenth configuration is as follows.
The traffic information acquisition means acquires traffic conditions on a road ahead of the user in the traveling direction as the traffic information.
According to the virtual image display device having the above-described configuration, an appropriate position that predicts an interval to an obstacle (for example, a vehicle ahead) in the user's line-of-sight direction based on a traffic congestion situation on the road on which the user moves and does not overlap with the obstacle. It is possible to generate a virtual image.

The eleventh configuration is as follows.
The generation distance control means controls the generation distance to be shorter as the degree of congestion on the road ahead in the traveling direction of the user is higher.
According to the virtual image display device having the above-described configuration, when the degree of traffic congestion on the road on which the user moves is high, it is predicted that the distance to the obstacle (for example, the vehicle ahead) in the user's line of sight is shortened, and the generation distance is By shortening it, it becomes possible to generate a virtual image at an appropriate position that does not overlap with an obstacle.

DESCRIPTION OF SYMBOLS 1 Head up display apparatus 2 Vehicle 3 Dashboard 4 Projector 5 Screen 6 Front window 7 Crew 8 Virtual image 9 Front camera 11 1st mirror 12 2nd mirror 14 Concave mirror 21 Projected area 22 Optical path 23 Mirror drive motor 31 CPU
32 RAM
33 ROM
34 Flash memory

Claims (11)

An image display surface for displaying images;
Virtual image generating means for generating a virtual image of the video by allowing a user to visually recognize the video displayed on the video display surface;
Traffic information acquisition means for acquiring traffic information ahead of the direction of travel of the user from an external server;
And a generation distance control unit that controls a generation distance that is a distance from the user to the virtual image based on the traffic information acquired by the traffic information acquisition unit. Speed acquisition means for acquiring the moving speed of the user;
The virtual image display device according to claim 1, wherein the generation distance control unit controls the generation distance based on a moving speed of the user.   The virtual image display device according to claim 2, wherein the generation distance control unit controls the generation distance to be shorter as the moving speed of the user is slower.   4. The virtual image display device according to claim 3, wherein the generation distance control means shifts the generation distance only in a direction in which the generation distance becomes shorter in the generation distance control based on the moving speed of the user. . The traffic information acquisition means acquires the traffic situation on the road ahead in the traveling direction of the user as the traffic information,
The generation distance control means includes
When the degree of congestion on the road ahead of the user's traveling direction is congestion or congestion, the generation distance is controlled based on the moving speed of the user,
5. The generated distance is a distance that does not depend on the moving speed of the user when the degree of congestion on a road ahead in the traveling direction of the user is smooth. The virtual image display device described. Having position acquisition means for acquiring the position of the user;
The generation distance control means includes
Until the position of the user passes through the end point of the road section where the congestion degree is congested or congested, the generation distance is controlled based on the moving speed of the user,
The distance that does not depend on the moving speed of the user is set as the generated distance after the user's position passes through the end point of a road section where the degree of congestion is congested or congested. The virtual image display device according to any one of 5. The generation distance control means includes
In the case where the user's position moves in a road section where the congestion degree is congested or congested, it is determined whether or not the moving speed of the user is at a speed corresponding to the congestion degree of the road section,
The distance generated not to depend on the moving speed of the user is set as the generated distance when it is determined that the moving speed of the user is not a speed corresponding to the congestion degree of the road section. Virtual image display device. Road type acquisition means for acquiring the road type of the road from which the traffic information was acquired;
8. The virtual image display device according to claim 1, wherein the generation distance control unit controls the generation distance based on a road type of the road from which the road information is acquired.   9. The generation distance control means, when the road type of the road from which the road information is acquired is a general road, controls the generation distance to be shorter than a high standard road. The virtual image display device described.   The virtual image display device according to claim 1, wherein the traffic information acquisition unit acquires a traffic congestion state on a road ahead of the user in the traveling direction as the traffic information.   The virtual image display device according to claim 10, wherein the generation distance control unit controls the generation distance to be shorter as the degree of congestion on a road ahead in the traveling direction of the user is higher.

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