JPH07248396A - Radiation resistant television camera and monitor - Google Patents

Abstract

PURPOSE:To provide a radiation resistant television camera by which the whole, television camera can be downsized and lightened by protecting an image pickup element by necessary minimum radiation protective materials when the radiating direction of radiation can be specified and on/from which the image pickup element can be simply mounted/demounted without spoiling the protective action, and a monitor having it. CONSTITUTION:A rearward opening housing space S is formed inside of an outside case 10, and a front wall part of the outside case 10 is composed of first, second and third radiation protective materials 13, 14 and 16, and from the rear, an inside case 20 having a CCD 50 is installed in the housing space S of the outside case 10, and light from the front of the outside case 10 is reflected by a mirror 40, and is introduced to the CCD 50.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a radiation resistant television camera used in a radiation environment such as gamma rays and neutrons, and a monitor equipped with the television camera.

[0002]

2. Description of the Related Art Conventionally, as a radiation resistant television camera of this type, for example, one described in Japanese Patent Laid-Open No. 4-188098 is known.

In such a television camera, a CCD camera (image pickup device) is provided at the approximate center of the spherical portion of the flask-shaped shield body.
And the image reflected by the mirror is taken by a CCD camera. Further, since the spherical portion of the shield body has a substantially uniform thickness, it is configured to shield radiation from all directions with respect to the CCD camera.

[0004]

By the way, when the radiation direction of the radiation can be specified, for example, when the radiation source is the imaging target, the shielding material can prevent the radiation having a straight traveling property from the imaging target. Occasionally, it is enough to block it.

However, the conventional television camera described above has a shielding material (radiation protection material) for shielding radiation from all directions.
Since it has a spherical shape, for example, when a radiation source is taken as an object to be photographed, a shielding material is provided more than necessary, which causes an increase in the size and weight of the entire TV camera. was there.

An object of the present invention is to protect the image pickup element with the minimum necessary radiation protection material when the radiation direction of radiation can be specified, and to reduce the size and weight of the entire television camera. Without sacrificing its protective action
It is an object of the present invention to provide a radiation resistant television camera in which an image pickup device can be easily attached and detached, and a monitoring device including the same.

[0007]

A radiation resistant television camera according to the present invention comprises an outer case having a housing space that opens rearward, and a radiation protection material provided on at least a front wall of a peripheral wall. An inner case that has an image sensor inside and is detachably attached from the rear of the outer case into the accommodation space; and a side of the outer case that is provided in the outer case and that transmits light from the front of the outer case. It is characterized by comprising a mirror that reflects inward from one side, and an optical path formed in the outer case and the inner case and guiding the reflected light from the mirror to the light receiving surface of the image sensor.

The monitoring apparatus of the present invention is characterized by comprising the radiation resistant television camera and display means for horizontally reversing and displaying an image on the image pickup device.

[0009]

According to the radiation resistant television camera of the present invention, an inner case having an image pickup device is detachably attached to the inside of an outer case provided with a radiation protection material on at least a front wall portion thereof, and further outside. The light from the front of the case is reflected by a mirror and guided to the image sensor, and the wall in front of the outer case is directed toward the radiation direction of the radiation, thus protecting the image sensor with the minimum necessary radiation protection material. And realized the size and weight reduction of the entire TV camera,
Further, the image pickup device can be easily attached and detached without impairing its protective action.

Further, the monitoring device of the present invention displays the image on the image pickup device of the television camera by horizontally reversing the display, and consequently displays the image of the object to be photographed without horizontally reversing the image. Improve the workability of monitoring.

[0011]

Embodiments of the present invention will be described below with reference to the drawings.

1 to 5 are views for explaining an embodiment of the present invention.

In FIG. 1, reference numeral 10 denotes an outer case having a substantially rectangular parallelepiped shape, and a housing space S which opens rearward (to the right in FIG. 1) is formed inside the outer case. Outer case 10
The peripheral wall, that is, the front (left in FIG. 1) wall and the four side walls are surrounded by the outer frame 11 and the inner frame 12, and between them, the first and second walls are formed. The radiation protection materials 13 and 14 are laminated. Further, in the front wall portion, an intermediate frame 15 is attached to the outside of the first protective member 13, and between the intermediate frame 15 and the outer frame 11, a third radiation for decelerating fast neutrons is provided. Paraffin as the protective material 16 is filled.
The frames 11, 12 and 15 are formed of an iron plate, and while maintaining strength as a frame, they also fulfill the function of decelerating fast neutrons.

The outer first protective material 13 is a neutron absorbing material for absorbing neutrons decelerated by paraffin as the third protective material 16, and is, for example, trade name "Neutron Stop (SM)". (Made by Ask Co., Ltd.)
Can be used. Chemical composition of the product (% by weight)
Has H of 6.5, O of 17.3, B of 15.7, Si of 30.3, and C of 3.02. The protective member 13 is formed in a flat plate shape, and a total of five pieces are provided on the peripheral wall of the outer case 10, that is, on each of the front wall portion and the four side wall portions. Further, the protective material 13 has a substantially uniform thickness on the peripheral wall of the outer case 10.

The inner second protective material 14 is a gamma ray shielding material, and is made of lead. The protective member 14 has a thickness W ₁ on the front wall portion and a thickness W ₁ on the other side wall portion.
₂ , which is set to be larger than W ₃ , and of the four side walls, the upper wall in FIG. 1 (hereinafter referred to as “upper wall”)
The thickness W ₂ of the protective material 14 in ( ₁ ) is set to be slightly larger than the thickness W ₃ in the other three side walls (W ₁ > W ₂ > W ₃ ). After all, the front wall portion of the outer case 10 is thicker than the other side wall portions.

The upper wall of the outer case 10 has a hole 11 penetrating the frames 11 and 12 and the protective members 13 and 14.
An optical path L is formed by A, 12A, 13A, 14A and a hole 22A of the upper surface plate 22 described later.
The optical path L is a truncated cone-shaped through hole whose diameter increases outward. Also, the frame 1 on the front wall
A guide pin 17 protruding rearward and an intermediate portion of a leaf spring 18 are attached to the inner surface of 2. The guide pin 17 has a tapered cylindrical shape, and both ends of the leaf spring 18 are shown in FIG.
It projects backward as shown in. A stopper piece 19 protruding upward is attached to a fixed position on the inner surface of the frame 12 in the lower wall portion in FIG.

Further, a mirror 40 is attached to the outer surface of the frame 11 on the upper wall of the outer case 10 by a bent frame 41. Mirror 4
As shown in FIG. 1, 0 reflects the visible light incident from the front A direction into the optical path L and transmits radiation such as fast neutron rays and γ rays. For example, the reflecting surface is It is formed by aluminum vapor deposition. The mirror 40 formed by aluminum vapor deposition is less susceptible to the effects of radiation than those formed by silver vapor deposition or plating.

In FIG. 1 and FIG. 2, 20 is an outer case 1.
The image pickup device is an inner case of a substantially cubic shape housed in the housing space S of 0, and is formed by joining the side plate 21 (see FIG. 3) having a U-shaped cross section, the top plate 22, the front plate 23, and the rear plate 24. CCD as
An accommodation space S _{1 for the} (charge coupled device) 50 is formed. A guide plate 25 having a substantially C-shaped cross section as shown in FIG. 3 is attached to the lower surface of the side plate 21,
Further, a surface plate 26 is attached behind the guide plate 25 and the rear plate 24. These plates 21 to 26 are all formed of iron plates and also have a function of decelerating fast neutrons.

As shown in FIG. 4, the CCD 50 is held between two supporting plates 28, 29 having a substantially V-shaped cross section by bolts 27, 27, and further, a leg portion 28A below one supporting plate 28. , 28A are bolts 30, 3
It is attached to the inner surface of the side plate 21 by 0. In this way, the CCD 50 is supported in the accommodation space S ₁ , and its light-receiving surface is parallel to the upper plate 22, that is, along the direction of arrow A in FIG.
It faces the hole 22A formed in 2. Also, the accommodation space S
Within _1, it is accommodated driver 51 for driving the CCD 50, their CCD 50 and the driver 51 is connected to a connector 52 which is attached to the surface plate 27.

Lead is provided on the inner surface of the rear plate 24 as a fourth protective material 31 for shielding γ-rays, and the accommodation space S ₁ is filled with a fifth protective material 32 for absorbing γ-rays. Has been done. As the protective material 32, for example, a trade name “Gamma Stop (LA)” (manufactured by Ask Co., Ltd.) can be used, and its chemical composition (% by weight) is
H is 0.8, Si is 3.7, C is 3.2, and Pb is 90.
2, O is 2.1.

Further, the front plate 23 is formed with a guide hole 23A which can be fitted with the above-mentioned guide pin 17.
Inside the guide plate 25, a hook-shaped body 33 is supported rotatably around the support pins 34 in the directions of arrows B ₁ and B ₂ . The hook-shaped body 33 is formed with a hook portion 33A that can be engaged with the stopper piece 19 described above, and is biased in the direction of arrow B ₁ by a spring (not shown). In addition, the hook-shaped body 33 has an operation portion 33B which projects rearward through a hole 26A formed in the surface plate 26.
Are formed.

The television camera thus constructed is, for example, placed on the camera platform 60 as shown in FIG. 5, and is also installed in the radiation room R ₀ to monitor the radiation source. Used as a device. The platform 60 is, for example,
The television camera is panned and tilted, and is remotely controlled by a controller 61 outside the radiation room R ₀ . A connector 72 attached to one end of a camera cable 71 is connected to the connector 52 of the television camera, and the other end of the camera cable 71 is connected to the radiation chamber R.
_It is connected to an external camera control unit 73 of ₀ , and a monitor (display means) is further connected to the unit 73.
74 is connected. The monitor 74 laterally reverses and displays the image on the CCD 50, as described later.

Next, the operation will be described.

First, the inner case 20 is housed in the outer case 10 from behind. At that time, the inner case 20
Is inserted into the accommodation space S while the outer surfaces of the upper plate 22 and the guide plate 25 are guided by the inner surface of the inner frame 12 of the outer case 10 (see FIG. 3). The guide pin 17 of the outer case 10 is attached to the inner case 2
0 inside the guide hole 23A, gradually entering the inner case 2
0 is positioned. Further, both ends of the leaf spring 18 are shown in FIG.
As shown in FIG. 7, the inner case 20 is pressed and deformed to reduce the impact when the inner case 20 is inserted. When the hook-shaped body 33 is rotated in the direction of arrow B ₁ by a spring (not shown), the hook portion 33A engages with the stopper piece 19 as shown in FIG. 1 to prevent the inner case 20 from coming off. .

The outer case 10 housing the inner case 20 in this way is installed in the radiation chamber R ₀ as shown in FIG. 5, and the camera control unit 73 is attached to the connector 52 via the connector 72 and the camera cable 71. Connected.

The CCD 50 receives the visible light reflected by the mirror 40 through the optical path L and outputs a video signal. The installation angle of the mirror 40 is adjusted in advance according to the positional relationship between the monitored object and the CCD 50. In the case of this example, since the mirror 40 is attached to the outer portion of the outer case 10, it is easy to adjust the optical axis particularly when the CCD 50 is replaced with the inner case 20.

The CCD 50 takes an image of the object to be monitored which is horizontally inverted by the mirror 40. So C
The image on the CD 50 is horizontally reversed and displayed on the monitor 74. Therefore, the monitor 74 scans the image signal from the CCD 50 on the display screen in the left-right direction to invert the image. As another method of horizontally reversing the image on the CCD 50, for example, in the unit 73, a VRA
It is also conceivable that a video reversing means including M is configured so that the video signal from the CCD 50 is temporarily stored in the VRAM for each scanning line, and then is read from the reverse direction and output to the monitor 74. In this case, the scanning direction of the monitor 74 remains normal.

When the CCD 50 is replaced, the operating portion 33B of the hook-shaped body 33 is picked up and the hook-shaped body 3 is held.
3 is pulled out together with the inner unit 20 while being rotated in the direction of the arrow B ₂ , another inner case 20 is attached to the outer case 10.
Just insert it inside. The inner case 20 may be replaced together with the camera cable 71.

By the way, the radiation such as γ-rays and neutrons traveling straight from the direction of arrow A in FIG. 1 is used for the first, second and third protective members 13, which form the front wall of the outer case 10.
14 and 16, the CCD 50 is effectively shielded, so that the CCD 50 is effectively protected. Further, the other wall portion of the outer case 10 only needs to be capable of shielding thermal neutrons, and a two-layer structure of the protective materials 13 and 14 thinner than the front wall portion of the outer case 10 is also sufficient. Therefore, the outer case 10 and the TV camera as a whole are accordingly small in size.
Weight reduction is possible. Further, since the inner case 20 is replaced from the side opposite to the front wall portion of the outer case 10 that is protected intensively, there is no fear that the protective function is impaired.

When the television camera is moved by the platform 60, the range in which the radiation from the direction of the arrow A can be shielded by the front wall of the outer case 10 is set as the movable range of the television camera.

FIG. 6 is a view for explaining another example of the mounting structure of the mirror 40.

In the present example, the frame 41 of the mirror 40 is rotatably supported by the shaft 42 on the outer case 10, and the frame 41 is rotated by the motor 43 in the forward and reverse directions.
With 0, it is configured to rotate in the directions of arrows C ₁ and C ₂ . That is, the bearing 4 attached to the outer case 10
A rod 45 is vertically movably supported between 4A and 44B, and the tip of the rod 45 is a long hole 41A of the frame 41.
Is slidably and rotatably connected in the rod 45
The rack 46 provided in the motor is connected to the output shaft of the motor 43 via gears 47 and 48. Therefore, when the motor 43 rotates in one direction, the rod 45 rises and the mirror 40 rotates in the direction of the arrow C ₁ , and conversely, when the motor 43 rotates in the other direction, the rod 45 descends. Mirror 40 rotates in the direction of arrow C ₂ . Thus, by remotely controlling the motor 43, the angle of the mirror 40 is adjusted.

Considering the optical axis of the television camera shown by the dotted line in FIG. 6, the center of rotation of the mirror 40 is set so that the point P on the mirror 40 on the optical axis is not displaced by the rotation of the mirror 40. You may set it. That is, the mirror 40
An axis line that passes through the point P and extends in the front-back direction of the paper surface of FIG.

[0034]

As described above, in the radiation resistant television camera of the present invention, at least the inside of the outer case provided with the radiation protection material on the front wall portion and the inner case provided with the image pickup device from the rear side. Is detachably attached, and the light from the front of the outer case is reflected by a mirror to guide it to the image sensor. The image pickup device can be protected by the limited radiation protection material to reduce the size and weight of the television camera as a whole, and the image pickup device can be easily attached and detached without impairing the protective action.

Further, since the surveillance device of the present invention has a structure in which the image on the image pickup device of the television camera is horizontally reversed and displayed, as a result, the image of the object to be photographed is displayed without being horizontally reversed. Therefore, the workability of monitoring can be improved.

[Brief description of drawings]

FIG. 1 is a sectional view of a television camera showing an embodiment of the present invention.

FIG. 2 is a cross-sectional view of the inner case shown in FIG.

FIG. 3 is a view on arrow III in FIG. 1.

FIG. 4 is a view on arrow IV in FIG.

FIG. 5 is a schematic configuration diagram of a monitoring device of the present invention.

FIG. 6 is a side view of an essential part showing another embodiment of the present invention.

[Explanation of symbols]

 10 Outer Case 13 First Radiation Protective Material 14 Second Radiation Protective Material 16 Third Radiation Protective Material 19 Stopper Piece 20 Inner Case 33 Hook 50 CCD (Image Sensor) 71 Camera Cable 73 Camera Control Unit 74 Monitor ( Display means) R accommodation space

Claims (4)

[Claims] 1. An outer case, which has a housing space that opens rearward, is provided with a radiation protective material on at least a front wall of a peripheral wall, and an image pickup device provided inside the outer case. An inner case detachably attached to the accommodation space; a mirror provided on the outer case to reflect light from the front of the outer case toward the inside from the side of the outer case; And a light path formed on the inner case to guide the reflected light from the mirror to the light receiving surface of the image pickup device. 2. The outer case is provided with the radiation protection material on each of a front wall portion and a side wall portion, and the radiation protection material provided on the front wall portion is provided on a side wall portion. The radiation-resistant television camera according to claim 1, wherein the radiation-resistant television camera is thicker than the radiation protection material. 3. The radiation resistant television camera according to claim 1, wherein the mirror is provided on the outer case so that the angle can be adjusted. 4. A monitoring apparatus comprising: the radiation resistant television camera according to claim 1, 2, or 3, and a display unit for horizontally reversing and displaying an image on the image sensor.