How does the infrared athermal lens perform imaging

Background technique: In the civilian field, in addition to high resolution, small size and light weight, infrared athermalized lenses are also required to have low cost and maintain working performance in different high and low temperature environments. However, most infrared optical athermal lenses currently on the market generally use three or more optical structures, and their basic types are positive, negative, and positive refractive powers. They use single crystal germanium, zinc selenide, etc., to cooperate with the sulfur system. To achieve optical athermalization. Because materials such as single crystal germanium and zinc selenide are scarce, expensive, and high in density, optical lenses are heavy and costly. This type of lens cannot meet the needs of the civilian market. Technical realization elements: To In view of the shortcomings of the prior art, the technical problem to be solved by the present invention is to provide an economical infrared athermalized lens and imaging method. In order to solve the above technical problems, the technical solution of the present invention is: an economical infrared athermalized lens, the optical imaging system of the lens is provided with a positive meniscus lens A and a positive meniscus lens B along the light from left to right. , The air space between the positive meniscus lens A and the positive meniscus lens B is 14.1mm, and the positive meniscus lens A and the positive meniscus lens B are both chalcogenide glass lenses. Further, the focal length of the optical imaging system of the lens is f, where the focal lengths of the positive meniscus lens A and the positive meniscus lens B are f1 and f2, respectively; and the focal length f satisfies the following ratio: 1.5<f1/f<3 , 0.5<f2/f<2.0. Further, a parallel flat plate is arranged between the positive meniscus lens B and the image surface of the IMA. An economical infrared athermalized lens imaging method: the light enters the meniscus positive lens A and the meniscus positive lens B in sequence, and then imaging is performed. Compared with the prior art, the present invention has the following beneficial effects: reasonable design, simple system structure, small volume, light weight, low cost, and mass production can be realized.