Numerical investigation of method combined Doppler effect with multi-beam laser heterodyne for measurement of the small angle

This paper proposes a novel method is used to measure angle, namely multi-beam laser heterodyne measurement for angle. This method is the combination of Doppler effect and heterodyne technology, the oscillating mirror is placed in the measurement light path, it can load the information of angle to the frequency difference of the multi-beam laser heterodyne signal by the frequency modulation of the oscillating mirror, this method can obtain many values of small angle after the multi-beam laser heterodyne signal demodulation simultaneously and the measurement accuracy can be improve by averaging these measure values. Case of small angle measurement, this novel method is used to simulate measurement incident angle of standard plane mirror by MATLAB, the obtained result shows that the relative measurement error of this method is just 0.5216% and the measurement accuracy can be improve.