在读出电路有限的像元面积内获得尽可能大的电荷存储量是实现甚高灵敏度红外探测器的关键。基于脉冲频率调制的像元级模数转换(ADC)是实现甚高灵敏度红外探测器读出电路的主要方法, 阐述了像元级脉冲频率调制ADC的原理, 介绍了美国麻省理工学院林肯实验室、法国CEA-LETI在像元级数字读出电路的研究进展。作为从立体空间拓展电路密度的新技术, 介绍了三维读出电路的研究进展。最后介绍了昆明物理研究所甚高灵敏度红外探测器读出电路的研究进展。利用像元级ADC技术和数字域时间延迟积分(TDI)技术, 昆明物理研究所研制的长波512×8数字化TDI红外探测器组件, 峰值灵敏度达到1.5 mK。

The key to realize very high sensitivity infrared detector is to obtain as much charge storage capacity as possible in the limited pixel area of readout circuit. The pixel-level ADC based on pulse frequency modulation is the main method to realize the readout circuit of very sensitive infrared detector. The principle of pixel-level pulse frequency modulation ADC was described. The progress of pixel-level digital readout circuit in MIT Lincoln Laboratory of the USA and CEA-LETI of France were introduced. As a new technology of expanding circuit density from three-dimensional space, the progress of 3D readout circuit was introduced. Finally, the development of readout circuit for very high sensitivity infrared detector in Kunming Institute of Physics was introduced. Using pixel-level ADC technology and digital domain TDI technology, the long-wave 512×8 digital TDI infrared detector assembly was developed by Kunming Institute of Physics with the peak sensitivity of 1.5 mK.