LASER HETERODYNE INTERFERENCE MEASURING DEVICE AND METHOD BASED ON PLANE MIRROR REFLECTION

摘要

The present invention relates to a laser heterodyne interference measuring device and method based on plane mirror reflection. The laser heterodyne interference measuring device comprises a dual-frequency laser, a first photoelectric receiver, a second photoelectric receiver, a first polarizing beam splitter, a second polarizing beam splitter, a third polarizing beam splitter, a quarter-wave plate, a corner cube mirror, an optical compensating mirror, and a measured plane mirror. According to the method, two spatial isolation incident light beams of different frequencies are utilized for heterodyne-interference measurement, and optical paths of the measured light beam and the reference light beam are balanced by means of the optical compensating mirror. In the method, the measured plane mirror reciprocates in the propagation direction of incident light beams. By means of the present invention, optical non-linear errors and optical thermal drift errors in laser heterodyne interference measurement are inhibited, a light path structure is simplified, and the accuracy of laser heterodyne interference measurement is increased.