JPS6283717A - Night vision device - Google Patents

Abstract

PURPOSE:To easily confirm visually the target object by providing the control circuit to control the liquid crystal shutter, the video signal converting circuit to convert the output from the image sensor to the video signal and the monitor. CONSTITUTION:The output signal of a two-dimensional image sensor 22 is inputted to a liquid crystal shutter control circuit 24, and the liquid crystal shutter control circuit 24 sets the output value from the two-dimensional image sensor 22 corresponding to the light with the strong background beforehand as the limit value whether or not the light of a liquid crystal part 8 is transmitted. When the strong background light is made incident, the difference signal is used and action is executed so that the electric potential difference between a special transparent mosaic electrode 5 of the liquid crystal shutter part 8 onto which the strong background light is made incident and a transparent counter electrode 7 can be zero. Thus, while the strong background light is interrupted, a target object 1 can easily be observed by the monitor.

Description

[Detailed Description of the Invention] [Industrial Field of Application J] The present invention has a control circuit that controls a liquid crystal shutter according to the output from a liquid crystal shutter unit and a two-dimensional image sensor with seven eyes, and The present invention relates to a night vision device having a high degree of element amplification even in the presence of a strong element.

[Conventional technology]

Conventional night vision devices are configured as shown in the second factor.

Light from a target object 1 illuminated by weak particles such as interlayers is collected by an objective lens 2 and focused on a seven-eye lens plate surface 12 of an image intensifier 10. The image on the fiber root plane 12 is transmitted through the fiber 13 and reaches the photocathode 14. Original electrons according to the original intensity fly out from the photocathode 14, and are accelerated and focused by the electrode 15.

Further, the light is multiplied by the microchannel secondary electron multiplier 17, collides with the fluorescent screen 19, and is changed into two sounds. The image is transmitted through the 7 eye bars 20, and the fiber plate surface 21
reach. Furthermore, the image is captured by two-dimensional image sensor-2
2 fiber 231 - transmitting two-dimensional image sensor -
Reach 22. The two-dimensional image sensor 22 converts the optical signal into a signal fJ.

This signal is input to the video signal conversion circuit 25, converted into a video signal, and then input to the monitor 26 after t.

Then, the image on the monitor 26 is observed. At this time, the high voltage control circuit 11 controls the photocathode 14. A high voltage is supplied to the electrode 15°, the microchannel secondary electron multiplier input surface 16°, the microchannel secondary electron multiplier slope output surface 18°, and the phosphor screen 19.

The current flowing between the micro channel secondary electron multiplier board input surface 16 and the micro channel secondary electron multiplier Sakaide direction 18 is detected, and the current value is determined.

An image intensifier 100 is applied between the microchannel secondary electron multiplier input surface 16 and the microchannel secondary electron multiplier output surface 18 to increase the voltage value kW so that the brightness of the phosphor screen 19 is saturated at a constant value. Komasu 111
! controlling the degree.

[Problem to be solved by the invention J] In the conventional night vision device described above, the value of the 11r current flowing through the microchannel secondary electron multiplier J7 corresponding to all original occultations from the entire field of view of the device is controlled by high voltage. Since it is controlled by circuit 11, if there is a fairly strong fjv source from target object 1 in the background within the entire field of view, the amplification degree of the device decreases and target object 1
? The drawback was that it was difficult to see.

[Means to solve all problems]

The night vision device of the present invention includes a liquid crystal shutter section 8t that blocks part of the light from the entire field of view, and a control circuit 24 that controls the objective lens 2 that forms an image of the target object 1 and the liquid crystal shutter section 8. '@: Has.

〔Example〕

The present invention will be described with reference to the inside.

FIG. 1 shows an embodiment of the present invention. The target object 1 and the background, which are illuminated by a weak source such as a star, are imaged onto the transparent mosaic electrode 5 of the liquid crystal shutter section 8 by the objective lens 3 of the front group. This liquid crystal shutter 8 has a transparent mosaic electrode 5
．． LCD 6. Transparent counter electrode7. It is composed of liquid crystal seal glass 4.

The transparent mosaic electrode 5 and the transparent counter electrode 7 correspond to each picture element of the two-dimensional image sensor 22. A voltage is applied in advance between the transparent mosaic electrode 5 and the transparent counter electrode 7 by the liquid crystal shutter control circuit 24, and the dipole arrangement of the liquid crystal 6 becomes perpendicular to the electrode due to the potential difference. is in a transparent state. The liquid crystal shutter control circuit 2 uses the output value from the two-dimensional image sensor 22.
4 operates so that the potential difference between the specific transparent mosaic electrode 5 and the transparent counter electrode 7 is eliminated, so that the liquid crystal 6 becomes opaque and blocks the p-source tube.

The rear objective lens 9 transfers the image on the transparent mosaic electrode 5 to the 7-fiber plate 12 of the image intensifier lO.
image is formed. The image of the fiber grade surface 12 is transmitted to the fiber 13't- and reaches the photocathode 14. Photocathode 14
Original electrons according to the original intensity fly out from the electron beam, which are accelerated and focused by the electrode 15, further amplified by the microchannel secondary electron multiplier 17, collide with the fluorescent screen 19, and are converted into nine electrons. The image is transmitted through the fiber 20 and reaches the fiber plate surface 21. Further, the seven images are transmitted through the fiber 23 of the two-dimensional image sensor 22 and reach the two-dimensional image sensor 22. In a two-dimensional image sensor, the original intensity is converted into an electrical signal. This signal is input to a video signal conversion circuit 25, converted into a video signal, and then input to a monitor 26. Then, the image on the monitor 26 is observed.

On the other hand, the output signal of the two-dimensional image sensor 22 is input to the liquid crystal shutter control circuit 24, and the liquid crystal shutter control circuit 24 uses the output value from the two-dimensional image sensor 22 corresponding to the strong light in the background in advance. Set it as the limit value for whether or not to allow the principal of S8 to pass through.

When strong background light enters, the difference signal S becomes full river.

It operates so that the potential difference between the special transparent mosaic electrode 5 and the transparent pair rO]ii electrode 7 of the liquid crystal shaft part 8 to which strong background light is incident is set to zero. Therefore, the target object can be observed with seven monitors when strong background light is blocked.

〔Effect of the invention〕

As explained above, the present invention is designed to block light and sound that degrades the visibility performance of the device when the target object 1 is from a fairly bright background.
By operating the image intensifier 1° at a high optical amplification degree, it is possible to realize a night vision device with improved visibility performance.

[Brief explanation of drawings]

FIG. 1 is a block diagram of an embodiment of the present invention. FIG. 2 is a block diagram of a conventional night vision device. DESCRIPTION OF SYMBOLS 1... Target object, 2... Objective lens, 3... Front group objective lens, 4... Liquid crystal seal glass, 5... Transparent mosaic electrode, 6... Nematic liquid crystal, 7...・Transparent pair electrode, 8... Liquid crystal shutter section, 9... Rear group objective lens, 10... Image intensifier, 11... High voltage control circuit, 12... 7 eyelid plate surface, 13... fiber, 14... photocathode,
15... Electrode, 16... Micro channel secondary electron multiplier input surface, 17... Micro channel secondary electron multiplier plate, 18... Micro channel secondary electron multiplier towards Sakaide, 19...・Fluorescent screen, 20...Fiber, 2
DESCRIPTION OF SYMBOLS 1... Fiber plate surface, 22... Two-dimensional image sensor, image sensor, 23... Fiber, 24... Liquid crystal shutter control circuit, 25... Video signal conversion circuit, 26... Monitor . Agent Patent Attorney Susumu Uchihara＼−、ノ

Claims (1)

[Claims] It includes an objective lens that blocks a portion of the light from the entire field of view of the night vision device and forms an image of the target object, and the object image is received by a photocathode and converted into an electronic image. An image intensifier that multiplies an electron image and displays it on a phosphor screen, a two-dimensional image sensor with a fiber that is in close contact with the phosphor screen, and a control that controls the liquid crystal shutter according to the output from the image sensor. A night vision device comprising: a circuit; a video signal conversion circuit that converts an output from the image sensor into a video signal; and a monitor.