四象限探测器的特性测试

研究了用四象限探测器检测光斑中心位置时,入射光斑的各种特性和外部环境对象限探测器输出产生的影响。通过理论推导得出了入射椭圆高斯光斑时光斑中心位置与探测器输出的关系公式及检测灵敏度公式;搭建实验系统完成了室内及野外测试实验。实验结果表明,室内环境下探测器具有较高的检测精度与细分能力;在极限灵敏度下通过数字滤波可以使器件具有36细分的能力;测量了象限探测器的电压特性,完成了背景光特性、光斑大小特性、信噪比特性测试实验。野外实验表明,光强闪烁对探测器影响很大,当大气折射率结构常数为10-16时,距离在830 m时器件仅具有7细分能力,距离在12.5 km时基本没有细分能力,已经无法进行光斑检测。

Experimental testing on characteristics of four-quadrant detector

The basic characteristics of incident spots and effects of external space environments on a four-quadrant detector were researched when it was used to detect the spot center. The formulae of the output and sensitivity of the detector were proposed when the incident spots showed an elliptical Gaussian-distribution. An experimental system was set up to test and verify the characteristics of the quadrant detector in an indoor test and a field test. Experimental results demonstrate that the detector has higher detection accuracy and subdivision in the indoor test, and can offer a 36-subdivision with digital filtering at a limited sensitivity. By the voltage characteristic curves, the background lights, spot sizes and the ratio of signal to noise were studied. The experiments in the field were also completed between the two spots of 830 m and 12.5 km. It is pointed out that the influence of irradiance scintillation on the detector is rigider than that of the indoor test. When the refractive index structure parameter is 10^－16, the subdivision is only 7 in a distance of 830 m, furthermore, it can not detect spots in 12.5 km for the subdivision is invalid.