A reflective point-diffraction carrier-synchronous phase-shifting interference detection device and detection method

Abstract

The invention belongs to the field of optical interference detection, particularly relates to a reflective point-diffraction carrier synchronization phase-shifting interference detection device and a special detection method thereof. The device includes a light source, a collimation and beam expanding system, a first polaroid, a quarter-wave plate, a first lens, an unpolarized beam splitter prism, a second polaroid, a first plane mirror, a second plane mirror, a second lens, a polarized beam splitter prism, a first image sensor and a second image sensor. According to the invention, as the bandwidth usage efficiency of a charge coupled device (CCD), field use ratio of the CCD, real-time measurement, anti-jamming capability and the system complexity are all taken into consideration, the integral performance of the system is improved; the structure is simple, the cost is low, special optical elements such as gratings and polaroid groups are not needed; a microobjective is introduced, so that the method can be applied to micro measurement; and the device provided by the invention requires no change of the optical path during the operation, and is convenient and flexible to operate, high in stability and low in system complexity.

Description

technical field [0001] The invention belongs to the field of optical interference detection, in particular to a reflective point-diffraction carrier synchronous phase-shifting interference detection device and a special detection method thereof. Background technique [0002] Optical phase-shifting interferometry is a non-contact, high-precision full-field measurement method, which is widely used in the fields of optical surface, deformation and thickness measurement. Commonly used interferometry methods include off-axis interferometry, time coaxial interferometry and space coaxial interferometry. Off-axis interferometry separates the terms needed to recover the phase from the interfering terms by introducing a tilt angle between the object and reference beams, causing the interferogram to generate a carrier wave. However, the introduction of the carrier makes the bandwidth of the CCD not fully utilized. The time and space coaxial interferometry does not need to introduce a...

AI Technical Summary

Problems solved by technology

This method has a very good anti-interference ability, but it has the disadvantage of the time phase shift coaxial method, and it needs the actuator to move the polarizer to achieve phase shift, which increases the complexity of the system

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