为测量红外模拟探测器量子效率, 搭建了基于参量下转换效应的测量系统.利用光学参量振荡器调谐输出的2 576.5 nm波长连续激光束作为泵浦源、ZnGeP2晶体作为非线性晶体, 获取了3.42 μm和10.4 μm的相关光子对.实验中通过将采集到的两个通道的光电流/电压信号转换为等效光子计数, 并利用两光路平衡测量的方法对每个模式的平均光子计数进行校正, 实现了碲镉汞红外模拟探测器在10.4 μm处的绝对功率响应度定标, 得到了相对合成不确定度优于4.53%的定标结果.

The measurement facility based on parametric down-conversion technique is established to measure the quantum efficiency of the infrared analogy detector. Uses the CW laser beam of 2 576.5 nm wavelength tuning out of Optical Parametric Oscillator (OPO) laser as the pump source and the ZnGeP2 crystal as the nonlinear crystal, obtained the correlated photon pairs of 3.42 μm and 10.4 μm. The charge amount of the collected photo-current/voltage signal is converted into the equivalent photon counting, and the dual channel data fluctuation is carried out for the average photon counting of each mode through the method of double light path balance measurement, realized the absolute power responsivity calibrated of an MCT infrared detector at 10.4 μm, the results show a relative combination uncertainty of about better than 4.53% for this calibration method.