提高短波红外光谱仪信噪比的均衡曝光技术

A Balanced Exposure Technique to Improve the Signal to Noise Ratio of a Shortwave Infrared Spectrometer

针对短波红外焦平面光谱仪传统曝光方式在一大类应用场景中的不足之处,提出了一种提高短波红外焦平面光谱仪成像信噪比的均衡曝光技术:即给予焦平面上不同光谱维以不同的积分时间来提高整个焦平面的成像信噪比。实验系统包括中科院上海技术物理研究所自主研制的短波红外焦平面探测器、探测器驱动电路、信号采集与处理电路、上位机软件等。实验对比了3.31 ms、5.76 ms、8.22 ms、10.68 ms、13.14ms这5档积分时间的信噪比及其对比,经过测试,在忽略驱动及读出电路噪声的情况下,实验值与理论值接近,该技术有效提高了红外光谱仪成像信噪比。

The traditional exposure methods of shortwave infrared focal plane spectrometer have shortcomings in a variety of applications.This paper proposes a balanced exposure technique to eliminate these shortcomings.To improve the signal to noise ratio of the spectrometer,different spectral dimensions are given different integral times.We built an experiment system that included a shortwave infrared focal plane detector,a driver circuit,a signal acquisition and processing circuit,and PC software.The results of five different integral times(3.31 ms,5.76 ms,8.22 ms,10.68 ms,13.14 ms)and the contrast between them are close to the theoretical values.We conclude that this exposure technique can significantly improve the signal to noise ratio.