天体的红外成像探测在天文学领域中有其特殊和重要的作用,高性能红外探测器是红外天文观测的关键器件,因此红外焦平面阵列探测器性能参数的测试评价对于红外天文观测具有非常重要的意义。针对天文应用的特殊性,通过分析红外焦平面阵列(Infrared focal plane array,IRFPA)探测器的特点,给出了增益、读出噪声、线性和暗流等性能参数的测试原理和方法,建立了测试平台,该测试平台可实现1~14μm波长范围的IRFPA探测器性能参数测试;完成了一台采用国产3~5μm HgCdTe芯片研制的IRFPA探测器性能参数的测试。测试结果表明,该IRFPA探测器的线性度非常好,可以达到99.9%以上,但读出噪声和暗电流较大,与国外为天文观测研制的高性能探测器相比尚有很大的差距。
Infrared imaging detection of astronomical objects is of great importance in astronomy and astrophysics.A high-performance infrared detector is crucial to infrared astronomical observations.The performance test and evaluation of an infrared focal plane array(IRFPA)detector in this article are significant for infrared astronomy.According to the particularity of astronomical application,we give test principles and methods of performance parameters such as gain,readout noise,linearity and dark current,by analyzing characteristics of an IRFPA detector.A laboratorial testing platform is established to realize the performance test of an IRFPA detector with a wavelength range of 1~14μm.We have completed a performance test of an IRFPA detector made of a domestic 3~5μm HgCdTe chip.The test results reveal that the linearity of the IRFPA detector is pretty good,over 99.9%.Due to the relatively large readout noise and dark current,there is still a wide gap between the IRFPA detector and high-performance astronomical detectors abroad.