Method of improving the measurement accuracy of plane array imaging laser radar by pixel cascade.

ABSTRACT

The plane array imaging laser radar is the product of the combination of the area array imaging optical system and the range laser radar. With extended illumination and area array detection, the target can be measured in three dimensions without mechanical scanning. In this paper, a CMOS-type built-in optical mixer is used, which is a kind of matrix depth sensor. The size of a single pixel of the sensor chip determines its maximum resolution accuracy in two-dimensional distribution measurement, which also restricts the improvement of measurement accuracy to a certain extent. In this paper, a post-processing measurement method is proposed, which expands the processed data object from a single pixel to a regional pixel, transforms the measurement of displacement into the measurement of amplitude distribution changes, and effectively utilizes the cascaded characteristics between a single pixel and pixel area. The purpose is to break through the limitation of the size of a single pixel and thus improve the measurement accuracy. The validity of the method is verified by theoretical calculation and experimental measurements, and the measurement accuracy is improved by 6 times in practical test. This method can improve the measurement accuracy and performance of existing system equipment without breaking through the limitation of pixel physical size and will be highly interesting for practical applications.