Long focal length optical passive type athermalization infrared lens

Abstract

The invention relates to a long focal length optical passive type athermalization infrared lens. The long focal length optical passive type athermalization infrared lens, which is sequentially provided with a positive lens A, a negative lens B, and a positive lens C along a light incident direction. An air interval between the positive lens A and the negative lens B is 0.3mm, and the air interval between the negative lens B and the positive lens C is 52mm. The long focal length optical passive type athermalization infrared lens is advantageous in that characteristics such as optical passive athermalization and high transmittance are provided; by selecting optical materials reasonably, the excellent image quality of the optical system in different temperature ranges is guaranteed; an even asphere is adopted to balance the aberration of the system, and then the structure of the optical system is simplified, and the imaging quality of the optical system is better; a main lens tube adopts integrated design, and good mechanical property is provided; rigidity calculation is carried out in the design of the lens structure, the wall thickness of the lens is increased properly, and the inherent frequency of the lens is improved, and therefore the anti-vibration capability of the lens is improved, and the use requirements of the system are guaranteed.

Description

technical field [0001] The invention relates to an optical passive athermalized infrared lens with a long focal length. Background technique [0002] Under the influence of temperature changes in the infrared optical system, the refractive index of all optical materials, the curvature and spacing of each optical element will change accordingly, resulting in thermal defocus of the imaging quality system and a decrease in imaging quality. The athermalization technology of the optical system is to keep the focal length of the optical system unchanged or change little in a large temperature range through certain compensation technology, so as to ensure that the optical system has better image quality in this temperature range . [0003] At present, athermalization technology can be divided into three categories: electromechanical active, mechanical passive and optical passive. The electromechanical active type is realized by using temperature measurement technology and servo t...

AI Technical Summary

Problems solved by technology

[0002] Under the influence of temperature changes in the infrared optical system, the refractive index of all optical materials, the curvature and the interval of each optical element will change accordingly, resulting in thermal defocus of the imaging quality system and a decrease in imaging quality

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