甚高灵敏度红外探测器读出电路实现方法研究

Implementation method of very high sensitivity infrared detector readout circuit

随着红外焦平面技术的不断发展,红外焦平面探测器应用领域越来越广泛,这对红外焦平面探测器灵敏度提出更高的要求。本文首先分析了传统TDI型读出电路的降噪原理,通过仿真、测试及理论分析论述了传统TDI型读出电路提高红外探测器灵敏度的局限性,并计算出传统TDI型红外探测器所能实现的最优NETD值为4.19 mK。随后分析了像素级数字化TDI型读出电路的噪声来源及如何降低各类噪声,通过仿真结果结合理论计算得出像素级数字化TDI型红外探测器在应用32级TDI时NETD可达到亚毫K级,能够实现甚高灵敏度红外探测器的需求。

With the development of infrared focal plane technology,the infrared focal plane detectors have become widely used,which puts higher requirements on the sensitivity of infrared focal plane detectors.Firstly,In this paper,the noise reduction principle of the traditional TDI readout circuit is firstly analyzed,and the limitations of the traditional TDI readout circuit to improve the sensitivity of the infrared detector are discussed through simulation,testing and theoretical analysis,and the optimal NETD value of the traditional TDI type infrared detector is calculated to be 4.19 mK.Then the noise source of the pixel-level digital TDI readout circuit and the way to reduce various noise are analyzed.Finally the simulation results and theoretical calculations show that the NETD of 32 pixel-ADC TDI can achieve sub-K level,so the readout circuit can achieve the requirements of very high sensitivity infrared detectors.