一种适用于昼夜兼容CMOS图像传感器的动态范围拓展方法

A Dynamic Range Expansion Method for Day Night Compatible CMOS Image Sensor

摘要:

为了提高CMOS图像传感器的动态范围并应用于昼夜兼容成像,提出了一种新的动态范围拓展方法。该方法在像素中设置多个复位屏障,以延长曝光过程中光电二极管的饱和时间,同时通过在不同成像环境中切换像素积分电容大小,提高微光成像时的响应灵敏度和强光成像时的满阱容量,从而实现昼夜兼容高动态成像。经MATLAB仿真证明,该方法可将传统CMOS图像传感器的动态范围从61dB拓展到102dB。

Abstract:

In order to improve the dynamic range of CMOS image sensor and apply it to day night compatible imaging, a new dynamic range expansion method is proposed in this paper. In this method, multiple reset barriers are set in the pixel to prolong the saturation time of photodiode in the exposure process. At the same time, by switching the pixel integral capacitance in different imaging environments, the response sensitivity of low light level imaging and the full well capacity of high light level imaging are improved, so as to realize day night compatible high dynamic imaging. MATLAB simulation shows that this method can expand the dynamic range of traditional CMOS image sensor from 61dB to 102dB.