F19mm large relative aperture mechanical passive type athermalized lens and compensation adjusting method

Abstract

The invention relates to a f19mm large relative aperture mechanical passive type athermalized lens and a compensation adjusting method. The lens comprises an optical system and a mechanical structure. The optical system of the lens is equipped with a convex lens A, a concave lens B and a convex lens C that are sequentially arranged in a light incident direction. The mechanical structure of the lens includes a main lens barrel front set and a main lens barrel back set. A telescoping mechanism set, which is used for positioning and guaranteeing distances and which can telescope according to the principle of expansion with heat and contraction with cold, is disposed between the main lens barrel front set and the main lens barrel back set. The f19mm large relative aperture mechanical passive type athermalized lens has a compact structure, and mechanical passive type athermalization and high transmittance can be achieved. In the optical design, focal power is reasonably distributed, and through combination of lens barrel materials with different coefficients of expansion, the telescoping mechanism set expends with heat and contracts with cold to push the convex lens A to move so that image plane drift compensation is achieved, and temperature self-adaptive mechanical passive type athermalized features are obtained. The lens can match a long-wave infrared un-cooled 640*512,17[mu]m detector to carry out live recording and security monitoring tasks.

Description

technical field [0001] The invention relates to a f19mm large relative aperture mechanical passive athermal lens and a compensation adjustment method. Background technique [0002] The infrared lens has the advantages of strong anti-interference ability, strong ability to penetrate smoke and haze, can work all day and all day, and has good anti-invisibility ability. With the rapid development of infrared imaging technology, infrared lenses have been widely used in security monitoring and other fields. However, the environment in which infrared lenses are used is complex and often undergoes large temperature changes. Compared with the optical materials in the visible light band, the infrared optical materials used in infrared lenses have a larger temperature coefficient of refractive index. Under different ambient temperatures, the thermal expansion and contraction of optical materials and mechanical materials make the curvature radius and thickness of the lens As the air g...

AI Technical Summary

Problems solved by technology

However, the infrared lens is used in a complex environment and often experiences large temperature changes.

The infrared optical material used in the infrared lens has a larger temperature coefficient of refraction than the optical material in the visible light band. When the air gap changes, the refractive index of the optical material will also change with the temperature, which will cause the best image plane of the optical system to deviate, reduce the imaging quality of the optical system, and seriously affect the imaging performance of the lens

Therefore, in order to adapt to applications in different environments, the infrared optical system needs to be designed with athermalization so that it has a certain ability to adapt to temperature. However, there are few types of such lenses on the market at present, which cannot meet the needs of the market.

Images