A 20x medium-wave continuous zoom lens with an ultra-short non-diffractive surface

Abstract

The present invention proposes an ultra-short non-diffraction surface 20 times medium-wave continuous zoom optical lens, which has an objective lens group, a single-lens zoom group, a single-lens compensation group, a fixed lens group and a focusing lens group in sequence along the optical path; the first optical The axial space length from one surface to the last optical surface is 110mm; changing the position of the single lens zoom group and single lens compensation group along the optical axis can achieve 20 times continuous zoom. The present invention adopts aspheric surface, material optimization, rational allocation of focal length, shortens the lens length, and has a compact structure. The axial length from the first optical surface to the last optical surface is only 110 mm, and the image quality remains good during the 20 times zooming process. Moreover, the optical system does not use a diffraction surface, which improves the energy transmittance of the system and the sensitivity to temperature difference of the system, and reduces the processing difficulty and cost. The assembly is simple and easy for mass production.

Description

technical field [0001] The invention relates to a 20-fold medium-wave continuous zoom lens with an ultra-short non-diffraction surface, belonging to the field of optical technology. Background technique [0002] The infrared continuous zoom thermal imager is an imaging system whose focal length can be changed continuously, while the position of the image plane remains stable and the image quality remains good during the zooming process. In order to obtain images of different sizes on the image plane of a fixed-focus infrared camera, the distance between the target object and the lens must be changed or a lens with a different focal length must be replaced. The infrared continuous zoom thermal imager can continuously change the focal length of the system. Therefore, it can obtain target images of continuously changing sizes on the image plane, which is very beneficial for photoelectric detection, reconnaissance, and tracking. [0003] The usual infrared continuous zoom lens ...

AI Technical Summary

Problems solved by technology

In addition, most domestic continuous zoom optical systems use a diffractive surface to correct chromatic aberration. The use of a diffractive surface will reduce the energy transmittance of the lens, reduce the temperature sensitivity of the system, and increase the difficulty and cost of lens processing. Therefore, an ultra-short continuous zoom without a diffractive surface is developed. Optical systems are in great demand

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