JP2586366Y2 - Infrared camera - Google Patents

Description

[Detailed description of the invention]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an infrared camera used in an infrared thermal imaging apparatus, and more particularly to an infrared camera constructed so that dust does not enter an optical scanning mechanism.

[0002]

2. Description of the Related Art Generally, an infrared camera used in an infrared thermal imaging apparatus for detecting infrared radiation emitted from the surface of a subject and displaying the temperature distribution as a visible image (thermal image) is shown in FIGS. It is configured as shown in FIG.
First, the optical system scanning mechanism of the infrared camera will be described. Light from the surface of the subject 1 is blocked from visible light 2 by the silicon window 4 provided in the opening 12 of the case 11, and only the infrared light 3 enters the infrared camera. The infrared ray (infrared ray image) 3 entering the interior is reflected by the first turning mirror 5 located on the same plane as the silicon window 4 in the direction of the vibration mirror 6 located almost on the same plane as the rotating mirror 7. Is done.

The reflected light (infrared light 3) is vertically shaken by about 10 ° by the vibration mirror 6 and is incident on each plane mirror 7a of the rotating mirror 7. Therefore, each plane mirror 7a
Since the vibration mirror 6 is vibrated in the vertical direction by the carbanometer 13, a portion of the surface of the subject 1 that is slightly displaced in the vertical direction is scanned in the horizontal direction.

Usually, the number of horizontal scanning lines of this type of apparatus is 100.
About a book. Since the octahedral rotating mirror 7 is used, the rotating mirror 7 must rotate at least 12.5 times while the vibration mirror 6 shakes by 10 °, and in fact, the return path of the vibration mirror 6 16 rotations in consideration of the time required for the rotation. That is, a range of 10 ° in the vertical direction is scanned by 16 rotations of the rotating mirror 7, and the incident infrared rays 3 are reflected in the direction of the second turning mirror 8, reflected in the direction of the condenser lens 9, and The light beam is converged by the condenser lens 9 and is incident on the infrared detector 10 where it is photoelectrically converted. And
The electric signal of the thermal image is amplified by an amplifier 14 and subjected to various kinds of signal processing by a processor 15.
6 is displayed.

[0005] The infrared ray 3 corresponding to 0.1 ° is incident on the infrared detector 10 by the one-plane mirror 7a.
When the next plane mirror 7b scans, the vibration mirror-6 is used.
Is shifted by 0.1 °, and a position shifted by 0.1 ° in the vertical direction from the portion previously scanned horizontally by the plane mirror 7a is similarly scanned. Therefore, the vertical mirror 10a of the subject 1 is scanned by 12.5 rotations of the rotating mirror 7, and the horizontal viewing angle (15 in this embodiment) is determined by the plane mirrors 7a of the rotating mirror 7 in the horizontal direction. °) is scanned. Therefore, in order to obtain a thermal image of 100 horizontal scanning lines in real time,
The rotating mirror 7 is set to rotate at a high rotation speed of 14,400 rpm, and a real-time thermal image signal of 15 screens can be obtained from the infrared detector 10 per second.

The rotating mirror 7 has eight plane mirrors 7a.
Are arranged in an annular shape, and each of the plane mirrors 7a is attached to a rotating shaft of a motor (not shown) with a plane angle parallel to the center of rotation. Rotating mirror-7
A mirror cover (not shown) is provided to prevent dust from adhering to the plane mirrors 7a... And to prevent noise caused by the rotation of the rotating mirror 7.
Covered with. Next, the infrared detector (sprite element) 10 is spaced apart from the silicon window 4 in the vertical direction, and is arranged as close as possible to the vertical plane where the silicon window 4 is located.

[0007]

[Problems to be solved by the invention] Infrared detector 10
Must be cooled to a constant temperature to maintain its sensitivity. However, since there are many heat generating sources inside the infrared camera, it is necessary to stabilize the environmental temperature, so that outside air is sucked and forcedly circulated to cool the inside of the infrared camera.

On the other hand, the use environment of the infrared camera has been greatly expanded in recent years, and since the infrared camera is used even in a place with a lot of dust, such as a waste cleaning plant, the dust enters into the inside by inhaling outside air. Dust adheres to the optical system such as the rotary mirror 7 and the like, which makes it impossible to accurately measure the amount of infrared rays, that is, the temperature. Therefore, it is conceivable to provide a filter at the outside air intake port.
In this case, there is a problem that the filter has to be frequently replaced and maintenance is troublesome.

[0009]

[Means for Solving the Problems] This invention consists of a window that transmits only infrared rays emitted from the surface of a subject,
A first folding mirror that receives the infrared light transmitted through the window and reflects the infrared light in the vertical direction; a vibrating mirror that receives the infrared light from the first folding mirror and scans the infrared light at a predetermined angle in the vertical direction; A galvanometer to be driven, a rotating mirror to receive infrared light scanned in a vertical direction by the vibrating mirror and scan the infrared light in a horizontal direction,
An optical scanning mechanism including a second folding mirror that receives the horizontally and vertically scanned infrared rays from the rotating mirror and reflects the infrared rays in the horizontal direction; and receives the infrared rays scanned by the optical scanning mechanism and receives heat. In an infrared camera equipped with a processor that amplifies a thermal image signal from an infrared detector that outputs an image signal and that performs image processing, a temperature calibration wall is erected in the gap between the rotating mirror and the galvanometer, A sensor for detecting the room temperature is placed in close proximity to the rotating mirror facing surface of the calibration wall, and a partition wall is provided between the optical system storage room containing the optical system scanning mechanism and the circuit system storage room containing the electric circuit. With this arrangement, the case main body is divided, and an air cooling device for introducing and exhausting outside air into the circuit system storage chamber is provided.

[0010]

The outside air is introduced into the circuit system storage chamber by an air cooling device, and is exhausted to the outside while cooling the inside. At this time, since the outside air does not pass through the optical system storage chamber in which the optical system scanning mechanism is stored, dust due to the outside air does not adhere to the optical system.

[0011]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described in detail with reference to FIGS. 1 is a plan view showing the inside of a housing 21 of the infrared camera, FIG. 2 is a front view of the infrared camera, FIG. 3 is a sectional view taken along line AA of FIG. 1, FIG. FIG. 5 is a sectional view of a main part of the cover 22, FIGS. 6 and 7 are plan and sectional views of a dust-proof packing 36, and FIGS.
It is the front view and side view of the packing 37 mounted | worn with 2. The same components as those in the conventional example have the same names and are denoted by the same reference numerals, and description thereof is omitted.

In FIG. 1 and FIG. 2, a case body 20 forming the outer shape of the infrared camera is provided with a housing 21 and a cover.
The interior of the housing 21 and the cover 22 is partitioned by an optical system storage chamber 24 by a partition wall 23.
And a circuit storage room 25, and lattice-shaped windows 26 and 27 serving as an outside air inlet and an exhaust outlet are provided on both side surfaces where the circuit storage room 25 is located.

The optical system storage chamber 24 contains a germanium window 4, a first folding mirror 5, a vibration mirror 6, a rotating mirror 7, a second folding mirror 8, a condenser lens 9, a galvanometer 13, and the like. , Sensor unit 10b of infrared detector 10
And so on. Further, a room temperature calibration wall 28 is provided between the carbanometer 13 and the rotation mirror 7, and a room temperature detection sensor 29 is provided on the rotation mirror 7 facing the room temperature calibration wall 28. Are arranged. In addition,
In this embodiment, the germanium window 4 is adopted depending on the wavelength of the infrared light to be transmitted, but a silicon window or the like may be used if the wavelength is different.

The circuit system storage room 25 is provided with a circuit board 39 such as the amplifier 14, the processor 15, etc., the infrared detector 10, its cooler 10a, an air cooling device 30, a terminal 31 and the like.

The partition wall 23 is provided to partition the inside of the case body 20 between the optical system storage room 24 and the circuit system storage room 25, and to prevent dust from entering the optical system storage room 24. As shown in FIGS. 4 and 5, the housing 21 and the cover 22 are provided so as to face each other. When the upper surface of the housing 21 is covered with the cover 22,
The main body 20 is configured to be divided into an optical storage room 24 and a circuit storage room 25 by a partition wall 23.

The partition wall 23 on the side of the housing 21 has a structure shown in FIG.
As shown in FIG. 2, a semicircular opening 32 communicating with the optical system storage chamber 24 and the circuit system storage chamber 25 is provided, and this opening 32 is closed from the sensor section 10b of the infrared detector 10. A tube 10c communicating with the rar portion 10a penetrates, and cable grooves 33, 34 for penetrating a cable (not shown) are similarly provided on both sides of the opening 32. It is transparent on the side.

As shown in FIGS. 6 and 7, the end of the partition wall 23 on the cover 22 side, that is, the portion that comes into contact with the partition wall 23 on the housing 21, has a cross section U formed of an elastic member such as rubber. A letter-shaped packing 36 is fitted. As shown in FIGS. 8 and 9, the opening 32 on the side of the housing 21 is made of an elastic member such as rubber so as to prevent dust from the circuit storage chamber 25 from entering the optical storage chamber 24. Part 3
A packing 37 having a hole 37a of size 2 is mounted. At least one surface of the partition wall 23 facing the two storage chambers 24 and 25 has a magnetic sheet such as permalloy.
A magnetic shield plate 38 formed of a shield member is fixed.

Next, the operation will be described. After arranging each part at a predetermined position in the housing 21, the cover-2
The packing 36 is fitted to the end of the partition wall 23 on the second side, and the tube 1 of the cooler 10a located at the opening 32 is fitted.
After the packing 37 is positioned at the portion 0c, the cable bundled with a tape is fitted into the cable grooves 33 and 34, and the upper surface of the housing 21 is covered with the cover 22.
The upper end of the partition wall 23 between the housing 21 and the cover 22 is tightly fixed to each other via a packing 36, and the gap between the optical system storage room 24 and the circuit system storage room 25 is an opening in which the packing 37 is provided. The portion 32 is communicated with the cable grooves 33 and 34 closed by cables.

Then, when the power supply of the infrared camera is turned on, the air cooling device 30 is driven, and the outside air is sucked through one of the windows 26 formed on the side wall of the case body 20, and the case is cooled.
The air is exhausted to the outside from the other window 27 while cooling the inside only through the circuit storage chamber 25 inside the main body 20.

At this time, the opening 32 is shielded by the packing 37 and the cables and the cable grooves 33, 3 are formed.
Since the gap with 4 is almost covered with the packing 36, the outside air containing dust flowing from the window 26 almost passes only through the circuit storage chamber 25 and does not enter the optical storage chamber 24.

However, since the motor for the rotating mirror 7 and the heat generating source such as the galvanometer 13 are provided in the optical system storage room 24, heat is generated by these and the optical system storage room is generated. The room temperature in 24 increases. Therefore, a measurement error occurs. Therefore, the temperature (the amount of infrared rays) from the subject 1 must be corrected for the environmental temperature in the optical system storage room 24.

Then, the infrared ray 3 radiated from the subject 1 having passed through the germanium window 4 is scanned by the rotating mirror 7, and the rotating mirror 7 first scans the room temperature calibration wall 28. Therefore, the environmental temperature detected by the room temperature detecting sensor 29 is calibrated using the temperature of the room temperature calibrating wall 28 as a reference temperature, and the actual temperature of the subject 1 is measured from Planck's radiation formula. The room temperature calibration wall 28 is
There is also an effect of reducing the wind noise of the rotating mirror-7. Therefore, even if the environmental temperature of the optical system storage room 24 becomes high, the temperature of the subject 1 can always be accurately measured.

[0023]

According to a first aspect of the present invention, there is provided a window that transmits only infrared rays emitted from the surface of a subject, a first folding mirror that receives the infrared rays transmitted through the window and reflects the infrared rays in the vertical direction. A vibrating mirror that receives the infrared light from the first folding mirror and scans it at a predetermined angle in the vertical direction, a galvanometer that drives the vibrating mirror, and receives the infrared light that is vertically scanned by the vibrating mirror and receives the infrared light. An optical system scanning mechanism including a rotating mirror that scans in the horizontal direction, a second folding mirror that receives infrared rays scanned horizontally and vertically from the rotating mirror and reflects the infrared rays in the horizontal direction, and performs scanning by the optical system scanning mechanism. Processor that amplifies the thermal image signal from the infrared detector that receives the infrared rays received and outputs it as a thermal image signal and performs image processing In the infrared camera equipped with a mirror, a temperature calibration wall is erected in the gap between the rotating mirror and the galvanometer, and a room temperature detection sensor is placed close to the rotating mirror facing surface of the temperature calibration wall, and the optical system scanning is performed. An air-cooling system that divides the case body by providing a partition wall between the optical system housing room in which the mechanism is housed and the circuit system housing room that houses the electric circuit section, and introduces and exhausts outside air into the circuit system housing room Since the apparatus is arranged, it is possible to always accurately measure the temperature of the subject even when the environmental temperature of the optical system storage room becomes high. Since the outside air containing dust passes only through the circuit storage chamber, the circuit storage chamber is air-cooled by the outside air, and dust from the outside does not enter the optical storage chamber and adhere to the optical storage chamber. In addition, since the temperature is calibrated with respect to the environmental temperature, no error occurs in the temperature measurement. In addition, since the case body is divided into two chambers by the partition wall, not only the dustproof effect, but also the temperature in the circuit storage room does not affect the optical storage room. You can do it. The room temperature calibration wall also has the effect of reducing the wind noise of the rotating mirror.

According to the second aspect of the present invention, the magnetic shield member is fixed to at least one surface of the partition wall, so that not only the effects of the first aspect of the invention but also the circuit system housing chamber and the optical system housing are provided. The two storage rooms can be shielded from each other so as not to be influenced by each other due to electromagnetic noise generated in the rooms.

[Brief description of the drawings]

FIG. 1 is a plan view of a housing showing an embodiment of the present invention.

FIG. 2 is a front view of the infrared camera showing the embodiment of the present invention.

FIG. 3 shows an embodiment of the present invention, and is an AA of FIG.
It is sectional drawing.

FIG. 4 shows an embodiment of the present invention, wherein a housing 2 is provided.
1 is a partially cutaway side view of FIG.

FIG. 5 is a cross-sectional view of a main part of the cover 22, showing an embodiment of the present invention.

FIG. 6 shows an embodiment of the present invention and is a plan view of a dust-proof packing 36. FIG.

FIG. 7 is a cross-sectional view of a dust-proof packing 36, showing an embodiment of the present invention.

FIG. 8 is a front view of a packing 37 mounted on the opening 32 of the partition wall 23, showing an embodiment of the present invention.

FIG. 9 is a side view of a packing 37 mounted on the opening 32 of the partition wall 23, showing an embodiment of the present invention.

FIG. 10 is a perspective view of a main part showing a conventional example.

FIG. 11 shows a conventional example, and is a plan view of a partially cut-out main part.

[Explanation of symbols]

 1... Subject 3... Infrared 4... Germanium window 5... First folded mirror 6... Vibration mirror 7. Mirror 8 Second folded mirror 9 Condenser lens 10 Infrared detector 13 Galvanometer 20 Case body 23 ··· Partition wall 24 ··· Optical system storage room 25 ··· Circuit system storage room 28 ··· Room temperature calibration wall 29 ··· Room temperature detection sensor 30 ··· Air cooling device 38 · ... Magnetic shield plate

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int.Cl. ⁶ , DB name) G01J 5/48 G01J 5/04 G01J 1/04

Claims (2)

(57) [Scope of request for utility model registration] 1. A window that transmits only infrared rays radiated from the surface of a subject, a first folding mirror that receives the infrared rays transmitted through the window and reflects the infrared rays in a vertical direction, and a first mirror that reflects the infrared rays. A vibrating mirror that receives the infrared light and scans it at a predetermined angle in the vertical direction, a galvanometer that drives the vibrating mirror, and a rotating mirror that receives the infrared light scanned vertically by the vibrating mirror and scans it in the horizontal direction An optical system scanning mechanism comprising: a second folding mirror that receives the infrared rays horizontally and vertically scanned from the rotating mirror and reflects the infrared rays in the horizontal direction; and receives the infrared rays scanned by the optical system scanning mechanism. And a processor for amplifying the thermal image signal from the infrared detector and outputting the thermal image signal as a thermal image signal, and for performing image processing. In the X-ray camera, a temperature calibration wall is erected in a gap between the rotating mirror and the galvanometer, and a room temperature detecting sensor is disposed in proximity to the rotating mirror facing surface of the temperature calibration wall; A partition wall is provided between the optical system housing chamber in which the scanning mechanism is housed and the circuit system housing room in which the electric circuit portion is housed to divide the case body and introduce and exhaust outside air into the circuit system housing room. An infrared camera having an air cooling device. 2. The infrared camera according to claim 1, wherein a magnetic shield member is fixed to at least one surface of the partition wall.