漏电流对CMOS探测器成像品质的影响分析

摘要

CMOS探测器近年来在工业、民用、航天等领域得到了广泛的应用,而漏电流对CMOS探测器成像品质影响的研究却较少.文章针对CMOS探测器在低读出速率时造成图像噪声过大的原因进行了分析,发现CMOS探测器的漏电流是产生该种图像噪声主要成因,并对不同读出速率下的像质进行了试验分析.理论和试验结果表明:在较低的读出速率时,CMOS探测器的漏电流产生的噪声过大,导致图像噪声的增大,影响了像质.因此,设计CMOS相机时应重点考虑低读出速率时,CMOS探测器漏电流对像质的影响,必要时要增加缓存,以便获得更好的像质.文章将为CMOS探测器在低速读出应用、设计提供一定的参考.%CMOS image sensor is widely used in industrial, civil, aerospace and other fields in recent years. However, the influence of the leakage current to the CMOS image quality is less studied. According to the mechanism analysis of the CMOS sensor, it is found that the leakage current of the CMOS image sensor is the main reason of the image noise. The leakage current mechanism of CMOS image sensor is analyzed and image quality is analyzed under different readout rates. Theoretical and experimental results show that the image noise is increased at lower readout rates, because of the influence of the leakage current of the CMOS. And the results show that the image noise will increase at the bottom of image. Therefore, designing CMOS camera should consider the effects of low readout rate to image noise, and it is necessary to increase cache for obtaining better image quality. The study of this paper will provide strong guidance for CMOS design in low-speed readout applications.