面阵CCD信号采集系统的噪声抑制

分析了CCD输出噪声及其一般抑制方法,提出了一种基于面阵CCD信号采集系统的噪声抑制方法。设计了CCD信号采集系统的噪声抑制电路和处理电路,应用于CCD442A型面阵CCD;并使用积分球对采集系统进行辐射定标,计算得到系统的信噪比。仿真和辐射定标实验表明,该面阵CCD信号采集系统具有相关双采样和暗电平校正功能,抑制了CCD输出信号的复位噪声和暗电流噪声;在中等照度条件下,系统信噪比达到40dB。

Noise Suppression of Area Array CCD Signal Acquisition

Based on properties of the noise module on the CCD output signal, general methods to suppress different noise were introduced. Based on area array CCD, the technique of suppressing noise of CCD signal acquisition scheme was presented. Noise suppressing and processing circuits of CCD signal acquisition scheme were designed. These circuits were used in signal acquisition scheme of CCD442A.The SNR of the acquisition system was also calculated by means of integrating spheres. According to the simulation and laboratory radiometric calibration experiment, the results show that the reset noise and the dark current noise are suppressed by the signal acquisition scheme of CCD442A with correlated double sampling(CDS) and black level offset compensation, and the system SNR exceeded 40 dB at medium illumination.