Non uniformity Soft Correction Algorithm for Four-quadrant Detector

摘要

The effect which photoelectric response non uniformity of four-quadrant detector used in target tracking act on the output characteristic linearity and tracking location accuracy is quantitatively analyzed, then a lower limit value of detector non uniformity must corrected is put forward, last a new method of multiple correcting non uniformity caused by differences of dark current, channel gain and photoelectric response between quadrants of detector is presented here. Based on compensation of light distribution, a linear fitting soft correction algorithm is applied to each quadrant photoelectric response in two-dimensions coordinate of detector by turns, this intelligent self correction method can control the non-linear error to 5percent and tracking location accuracy to 2percent. Compared to hardware correction of gain compensated and soft correction method that doesn't eliminate dark current it decreased the non-linear error 2percent, and increased location accuracy near 3percent.