Calculated intensity correlated imaging autocollimator and measurement method

Abstract

Disclosed are a calculated intensity correlated imaging autocollimator and a measurement method. The calculated intensity correlated imaging autocollimator comprises a light source, a digital micromirror device (DMD), a controller, a beam splitter, a lens, a device-under-test (DUT) reflective mirror, a CCD and an intensity correlated calculation module. A synchronous control module of the controller generates a synchronous clock signal which is applied to the DMD and the CCD. The intensity correlated calculation module records a light field modulation matrix generated by a light field modulation module and an echo signal received by the CCD simultaneously, and performs second-order intensity correlated calculation to indirectly calculate a tiny rotation angle of the DUT. The invention introduces a calculated correlated imaging method in quantum imaging technology to the design of the autocollimator, and can be used for effectively reducing the measurement errors caused by air turbulence and other factors and improving the sensitivity and stability of a system.

Description

technical field [0001] The invention relates to a computational intensity correlation imaging autocollimator and a measurement method, and belongs to the field of precision testing and measuring instruments. Background technique [0002] Autocollimator (also known as self-collimation micro collimator) is a testing instrument that uses the principle of self-collimation to measure small angles. It converts the rotation angle of the mirror on the test piece into the change of the line quantity on the receiving device of the autocollimator, and indirectly detects the slight angle change of the reflective surface by measuring the change of the line quantity. Autocollimator is mainly used in small angle measurement, flatness and parallelism measurement, etc. It is a commonly used measuring instrument in machinery manufacturing, aerospace industry, metrology, scientific research and other departments. [0003] Most of the autocollimators commonly used at this stage are CCD photoel...

AI Technical Summary

Problems solved by technology

However, whether it is a linear array CCD or an area array CCD photoelectric autocollimator, its accuracy is limited by parameters such as the number of CCD pixels and pixel size. Improve the measurement accuracy. In addition, the stability of the indication value of the traditional autocollimator is also severely challenged by the atmospheric disturbance caused by the heat generated by the machine.

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