Screen-type optical tester with adjustable environmental brightness

Abstract

A screen-type optical tester with an adjustable environmental brightness can adjust a target brightness and a background brightness independently, and is used for testing the visual resolutions of various hole types on targets. The overall structure of the optical tester with the adjustable environmental brightness is characterized in that five connecting pipes, a left hemispherical casing, a right hemispherical casing and a telescopic sleeve form a target optical access, a background optical access and a brightness environment separately, and a convex lens, multiple sets of optical attenuation slices and a screen are arranged in the target optical access, and a convex lens, three flat mirrors and multiple sets of optical attenuation slices are arranged in the background optical access; a light source is located on the focuses of the two convex lenses, and a sliding groove plate is driven by a stepping motor, and can do reciprocating motion in a limiting guide plate via a rack and pinion mechanism; three targets can be arranged in the sliding groove plate, each target can be put in and taken out from the sliding groove plate freely, and the flat mirrors in a sphere can change the incidence angle and the reflection angle of light rays by adjusting a rotating screw rod and a T-shaped groove plate, and an eye-distance can be adjusted by the telescopic sleeve.

Description

Technical field: [0001] The invention relates to a screen-type optical testing device which can independently adjust target brightness and background brightness, and is used for testing the visible resolution of various hole types on the target. Background technique: [0002] As an image input device, CCD cameras have been widely used in machine vision inspection, aerospace reconnaissance, robot navigation, industrial inspection, medical analysis and other fields in recent years. Its imaging quality directly determines the performance of its application system. In order to evaluate the imaging quality of CCD cameras, the minimum resolvable contrast ratio (MRC) evaluation index was introduced. Based on this, relevant scientific research departments at home and abroad have successively developed various systems for measuring MRC, mainly using the structure of a single integrating sphere or two overlapping integrating spheres. The front and back sides of the target are illumina...

AI Technical Summary

Problems solved by technology

However, the experimental results show that the adjustment range of the target brightness and background brightness in the above methods is too narrow, especially the adjustment of the target brightness is not uniform enough, and the requirements for the processing method are too high and the structure is too complicated

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