Method for eliminating swing error of three-dimensional laser imager

The invention discloses a method for eliminating the swing error of a three-dimensional laser imager, which can effectively eliminate the influence of the swing error on the measurement precision. The method comprises the following steps: (1) measuring the same distance position by adopting two transmitting signals with the phase difference of pi/4, acquiring phase values measured twice, and generating a measurement vector; (2) evaluating the noise covariance matrix in combination with related Kalman filtering and a maximum likelihood criterion method, and eliminating random errors in the working process of the three-dimensional laser imager by taking a measurement vector as an input value and a state vector as an output value; and (3) respectively taking the two measurement vector sequences obtained in the step (1) as input values of the step (2), outputting a state vector, returning to the step (1) for processing, generating a state vector sequence, calculating a measurement phase value, and respectively pr