面阵CMOS图像传感器性能测试及图像处理

CMOS图像传感器具有驱动简单、单电源供电、集成度高、功耗低、抗辐射能力强等优点。但是在航天光学遥感领域，CMOS图像传感器应用还不普遍。在该领域亟需大规模、高读出速度、大动态范围的图像传感器，CMOS图像传感器LUPA4000正是这样一款高性能面阵图像传感器，因此，选择LUPA4000作为研究对象，对其缺陷像元、光响应非均匀性、信噪比等性能指标进行测试。测试结果表明存在缺陷像元数量多、光响应非均匀性较大、信噪比较低等问题。根据测试结果采用暗背景扣除、缺陷像元替换、非均匀校正三种方法进行图像处理。对每种方法单独处理和各种方法组合处理的处理效果从图像信噪比和成像图像质量两方面进行分析评估，结果表明:非均匀校正联合缺陷像元替换的处理方法处理效果最佳。

Performance test and image processing of area CMOS image sensor

CMOS image sensor have the advantages of simple drive signals, single power supply voltage, high integration, low power consumption and strong radiation resistance. But in the field of space optical remote sensing, CMOS image sensor is not widely applied. The large-scale, high reading rate, high dynamic range CMOS image sensor is urgently in need. The 4 Megapixel CMOS image sensor of LUPA4000 is just such one. So LUPA4000 was chosen as the research target and its performance was tested. The image processing was conducted according to the results of performance test. In the research work, the parameters of defective pixels, response non uniformity(PRNU) and signal to noise ratio(SNR) were tested. The test results show that the CMOS image sensor of LUPA4000 has the following problems: the defective pixels are numerous, the PRNU is not ideal and the SNR is low. So the following image processing methods were adopted: dark background deduction to decrease the dark signal noise, defective pixels replacement to reduce the influence of defective pixels, and nonuniformity correction to reduce PRNU. The different processing combination among the three methods was applied .In order to evaluate the treatment effect of above processing combination, the contrasts of SNR and imaging quality between the original images and processed images were executed. The contrast results show that the method that combined defective pixels replacement with nonuniformity correction is the best combination.