Zhang Shuo, Bi Yong, Sun Lipeng, Chen Yongran
Appl Opt. 2020 Mar 10;59(8):2541-2550. doi: 10.1364/AO.384077.
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.
面阵成像激光雷达是面阵成像光学系统与测距激光雷达相结合的产物。通过扩展照明和面阵探测,无需机械扫描即可对目标进行三维测量。本文采用了一种CMOS型内置光学混频器,它是一种矩阵深度传感器。传感器芯片单个像素的尺寸决定了其在二维分布测量中的最大分辨率精度,这在一定程度上也限制了测量精度的提高。本文提出了一种后处理测量方法,该方法将处理的数据对象从单个像素扩展到区域像素,将位移测量转化为幅度分布变化的测量,并有效利用单个像素与像素区域之间的级联特性。目的是突破单个像素尺寸的限制,从而提高测量精度。通过理论计算和实验测量验证了该方法的有效性,实际测试中测量精度提高了6倍。该方法无需突破像素物理尺寸的限制即可提高现有系统设备的测量精度和性能,对实际应用具有很高的价值。