A kind of image square telecentric lens for space

Abstract

The invention provides an image-side telecentric lens for a space. The image-side telecentric lens comprises seven lenses. The image-side telecentric lens has a structure form in which the lenses are arranged in a sequence of a positive lens, a negative lens, a positive lens, a negative lens, a positive lens, a negative lens and a positive lens. A convenient-machining spherical surface structure form is adopted on each lens. The materials, the clear apertures, the thicknesses and the focal power absolute values of the lenses are different from one another. The focal length of an optical system is 35mm. A least F value is 2.5. The focal lengths are relatively short, but the focal power and material thermal expansion coefficient of the optical module are reasonably selected, thereby realizing mutual compensation in a vacuum high-temperature condition or a vacuum low-temperature condition, and obtaining relatively high ground and space environment adaptability. Relatively high imaging quality of the lens can be kept on a normal-temperature normal-pressure condition, a -50 DEG C vacuum condition, a +50 DEG C vacuum condition. Normal-temperature normal-pressure assembling of an object surface can be realized. Furthermore readjustment of an image surface after arriving at the space is not required.

Description

technical field [0001] The invention relates to a fixed-focus optical lens, in particular to a large aperture fixed-focus image-side telecentric optical lens suitable for space imaging applications. Background technique [0002] With the development of space exploration, the demand for optical imaging lenses suitable for space exploration is increasing, and the types are also increasing. However, the space environment is complex. Compared with the ground environment, not only there is a large temperature difference, but the pressure is also very different. Changes in temperature and pressure will lead to changes in the thickness, spacing, focal power, and relative refractive index of each lens in the optical system, resulting in changes in the image plane position of the optical system (that is, defocusing phenomenon), and a decrease in imaging quality. [0003] Aerospace products require as few moving parts as possible to ensure the reliability of the device. Under the con...

AI Technical Summary

Problems solved by technology

In addition, the focal length of the star sensor is usually about 35mm, and the F-number is relatively small (less than 3), but it measures the position of the center of mass of the target through the diffuse spot centroid algorithm. It is not necessary to consider the defocus problem caused by the environment such as thermal vacuum when designing. Diffuse circularity

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