SU1649345A1 - Device for checking lens quality - Google Patents

Abstract

The invention relates to the quality control of optical systems and is used to quickly control the quality of lenses by their optical transfer function. 1 of the invention is to reduce the time and increase the accuracy of control by eliminating the need to use a micro-lens. The images of the test object 2 are constructed by the collimator 3 and the test 6 lenses with translucent 4 lenses and 5 deflecting mirrors at controlled points of the center and field angle of the objective focal plane and analyzed with modulator 7 and photodetectors 8, 12 and 13, Modulator rotates uniformly with the help of the motor 11, at the same time performing a deep scan of the images by placing it on the axis of rotation at an angle to it. Signal processing and the search for the focal plane are carried out with the aid of a measuring instrument 10 of the angle of rotation of the position of the modulator in the elec. throne unit 9. 4 Il. (L

Description

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Measurements are made on signals coming from photodetectors J2 and 13. The measurement process is ultimately necessary to compare measured values with threshold values. If at least one of the three sum signals is less than the threshold value, the lens under test is considered unusable and the electronic unit supplies the appropriate signal.

Claims (1)

Invention Formula . A device for monitoring the quality of lenses, containing successively located a light source, a test object, a collimator lens, a deflecting mirror, an image analysis unit, including a disk modulator and a photoreceiver, an electronic unit containing a measuring and logic unit, and an expiration indicator, characterized in that, in order to reduce time and increase control accuracy, a translucent mirror is installed in front of the deflecting mirror at an angle of 45 and the optical axis of the collimator lens in the form of a glass plate on which two mutually perpendicular transparent slits are applied on an opaque background, 3 photoreceivers and a modulator of the angle of rotation of the modulator are inserted in the image analysis unit, three transparent tracks on an opaque background are printed on the disk of the modulator equally spaced parallel narrow transparent slits, deposited in concentric circles with radii R R „.zliJiE F. five &  -Ј five / where y is the distance in the modulator plane from the optical axis of the test lens to the controlled field of view; 1 - slot length on the modulator disk; R. is the distance from the axis of rotation of the modulator to the optical axis of the lens under test. moreover, in two modulator tracks with radii R- and R, the direction of each of the slots is oriented at an angle of 45 ° to the direction of the axis of rotation of the modulator Q and at an angle to each other in the third with a radius RT of the direction of slots the axis of rotation of the modulator, 25 GD f v moreover, the modulator is installed on the axis of rotation at an angle Od to it, i.e. where d l . & 1G arctg -, - error of the position of the focal plane of the test lens the axis of rotation of the modulator is parallel to the optical axis and is located relative to it so that the angle in the plane of the modulator disk with the vertical at the controlled point of the Eret- field, neither between the axis of rotation of the modulator and the optical axis of the test lens was 45 °, the photodetectors are located behind the plane of the modulator disk near the respective tracks, and the electronic unit includes three identical channels connected to the corresponding photoreceivers. Ж 1Ж-1 12 FIG. 2 ftsg.Z