CO2探测仪近红外焦平面无效像元检测方法

针对HgGdTe探测器均匀性差、无效像元多,过多无效像元会降低碳卫星CO2探测仪红外焦平面探测器探测精度,提出了一种基于探测器性能测试数据进行无效像元筛选的方法.首先利用CO2探测仪冷光学实验设备采集暗背景数据与响应度数据,然后计算暗背景数据的DN值均值与标准差、各个像元的响应度曲线,利用直方图阈值筛选出暗像元、亮像元、不稳定像元、平均拟合偏差较大等无效像元,最终利用各种无效像元集合交并集确定最终无效像元.结果表明:基于各种无效像元集合交并集确定最终无效像元的无效像元筛选方法准确度更高.通过遍历筛选出无效像元的响应值,从而确认了无效像元筛选的合理性.

Detective Method of Invalid Pixels of Near-infrared Focal Plane Arrays of CO2 Detector

As HgGdTe detector with poor uniformity has more invalid pixels, which can reduce the accuracy of near-infrared focal plane arrays of CO2 detector. One method based on the use of the performance test data of the de-tector is promoted. Firstly, dark background data and responsiveness data are collected using the thermal-vacuum test-ing equipment of CO2 detector. Then the mean value and standard deviation of dark background data and the response cure of each pixel are calculated. Dark pixels, bright pixels, unstable pixel, the pixels whose average fitting deviation are very big are selected using the histogram threshold. Finally,using the intersection and union of different invalid pix-el set determine the final invalid pixel set. The invalid pixel selection method based on the intersection and union of different invalid pixel sets is more accurate. The validity of this method is proved by scanning the performance of all the bad pixels detected above.