Application prospects of low-light night vision technology

A system that uses the above-mentioned generations of low-light image intensifiers combined with objective lenses and eyepieces and directly observes with the human eye is called a low-light direct viewing system. Also developing in parallel are low-light television systems, which usually use low-light image intensifiers and various camera tubes or CCD couplings. Low-light TV is used for nighttime observation through a monitor. The scene image is displayed on the fluorescent screen of the monitor, so it can be observed by multiple people at the same time. It can also be equipped with multiple monitors for observation by different command levels. Due to the large image area displayed by the monitor, human eyes can observe for a long time without fatigue. The image signal of low-light TV can be transmitted using both open-circuit and closed-circuit methods, and the monitor can also be set in any desired ideal position, so it has high concealment and mobility. Applying image processing technology to low-light TV can filter out noise, improve signal-to-noise ratio, and improve contrast and image quality. Low-light TV can be widely used in fields such as night surveillance, observation, aiming, driving, command, warning, navigation, bombing, landing, fire control, guidance, tracking, remote sensing, telemetry, reconnaissance photography and underwater operations.

In the military, low-light night vision technology has been used in night reconnaissance, aiming, vehicle driving, photoelectric fire control and other battlefield operations, and can be combined with infrared, laser, radar and other technologies to form a complete photoelectric reconnaissance, measurement and warning system . In other aspects, low-light image photon counter technology that can be used for early warning of long-range targets (100km satellites and missiles); pulse-gated observation low-light image intensifier; optically addressed microchannel spatial light modulator; GaAs cathode strong current pulse Laser (laser weapon) abroad has reached 1802/Acm, 35MW microwave output; high-gain, long-life, low-noise, high-current MCP technology matching the above corresponding types of low-light night vision devices, such as long-life, low-noise MCP technology ; High gain, high current, wide dynamic MCP technology, high gain, high resolution, low noise bending MCP technology, etc. The application of low-light night vision devices has not only made great progress in the military, but also allows us to see every bit of the dark world, becoming an indispensable part of future technology.

Low-light night vision device refers to the use of natural night skylights such as weak moonlight, starlight, atmospheric glow, and galaxy light as illumination at night, and uses a light intensifier to amplify and convert the weak photons reflected back from the target into a visible image to achieve Instrument for night observation. The important part of the low-light night vision device is the light image intensifier. Low-light night vision equipment consists of four main components: strong light objective lens, image intensifier, eyepiece, and power supply. In terms of optical principles, low-light night vision devices are special telescopes with image intensifiers.

Low-light night vision device is a type of night vision equipment developed in the 1960s. It is a nighttime observation instrument that uses an image intensifier to enhance the low light reflected from the target so that the human eye can see the target image. The low-light night vision device itself does not require an active light source and is a passive imaging system. Therefore, it overcomes the shortcomings of active infrared night vision devices that are prone to self-exposure and is more suitable for use by troops in night battles. Low-light night vision devices have been equipped with three generations of products in foreign countries. The first generation product was a low-light night vision device developed in the 1960s that used a three-stage cascade image intensifier. The second generation product is a low-light night vision device developed in the 1970s that uses a micro-channel plate image intensifier. The third generation product is a low-light night vision device developed in the 1980s that uses a highly sensitive gallium arsenide photocathode thin tube. In addition, low-light TV was developed using scanning imaging technology.

Weak natural light radiates through the target surface, enters the night vision device, and is focused on the photocathode surface of the image intensifier (coinciding with the back focal plane of the objective lens) under the action of the strong light objective lens, and excites photoelectrons; the photoelectrons are electronically optics inside the image intensifier Under the action of the system, it is accelerated, focused, and imaged, and bombards the fluorescent screen of the image intensifier at a high speed, and excites strong enough visible light, thus turning a distant target illuminated only by weak natural light into visible light suitable for human eyes to observe. image. Through further magnification of the eyepiece, more effective visual observation is achieved. The above process includes two conversions from optical images to electronic images and then to optical images.

Low-light night vision devices have been equipped with various arms of the land, sea and air. For example, individual soldiers carry binocular or monocular night vision glasses, helmet sights and mid-range weapon sights. As a warrior's nighttime super vision eyes, you can observe far and near, search, track and identify, etc. Similarly, low-light night vision devices installed on airplanes greatly improve pilots' vision at night and help the airplane land.

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