A Setting Method of Light Blocking Ring Based on Stray Light Suppression Angle

Abstract

The invention belongs to the field of stray light suppression design of an optical system, and relates to a setting method of a light blocking ring based on a stray light suppression angle. This setting method is mainly based on the properties of the matting paint sprayed on the inner wall of the hood and the minimum stray light suppression angle of the entire optical system. Through reasonable design and arrangement, the point source transmittance PST value at the suppression angle is minimized. The present invention first determines the type of matting black paint sprayed on the inner wall of the hood, then tests the surface properties of the type of matting black paint, and obtains the absorption properties of the matting black paint under different incident angles according to the test results, and selects the matting black paint with the highest absorption rate The incident angle α under the condition is used as the reference angle of the inclination of the light-blocking ring. After the coordinate point A of the ring tip of the primary light-blocking ring is determined, the inclination angle β of the light-blocking ring is set to 90°‑(α+θ) to obtain the The optimal PST value under the inhibition angle.

Description

technical field [0001] The invention belongs to the field of stray light suppression design of an optical system, and relates to a method for setting a light blocking ring based on a stray light suppression angle. Background technique [0002] PST (point source transmittance) is a key index to evaluate the stray light suppression ability of space optical system. [0003] For large-scale space observation cameras, when designing stray light suppression, the proposed index requirements are usually: the PST value of the entire system at the suppression angle θ is required to be less than 10 n The order of magnitude, n is a negative number, usually -7, -8, -9 or even lower. The principle behind this indicator is: under normal circumstances, the off-axis stray light suppression ability of the optical system increases with the increase of the off-axis angle. Enhancement, that is, the PST curve monotonically decreases with the increase of the off-axis angle. [0004] In engineeri...

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Problems solved by technology

[0004] In engineering practice, when the length of the hood of the optical system is fixed, especially when the size is limited, it is usually necessary to iterate the parameters of the light blocking ring repeatedly, so as to obtain the suppression angle under the premise of a certain length of the hood. The result at the smallest PST, in this process, often takes a long time, and it is not easy to obtain obvious improvement

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