基于高斯拟合测量CCD灵敏度均匀性

在精密度要求较高的图像测量领域中,CCD灵敏度的不均匀对测量精度有较大的影响。因此,提出了一种基于小孔衍射原理的高斯曲面拟合像面光场测量CCD灵敏度均匀性的方法。由于CCD自身的物理结构设计不均匀性、响应非线性以及暗电流等噪声因素使得光响应偏离实际值,该方法通过对CCD像面上感兴趣光场域进行高斯曲面拟合来确定零点像素的灰度响应。对所有像素测量完成之后通过归一化即可计算出CCD灵敏度均匀性。实验结果表明:对所使用的CCD47-10系列,计算其CCD灵敏度均匀性为2.14%。该测量方法基本满足设计原理简单、稳定性可靠、抗干扰能力强的要求,完成了快速、自动测量。

Measure CCD Sensitivity Uniformity Based on Gauss Fitting

In high accurate image measurement, The non -uniform of CCD sensitivity will affect the measured result. A Gauss curved surface fit light field on image plane method based on aperture diffraction theory to measure the CCD sensitivity uniformity is proposed. Because some noise fact like uneven material design, nonlinear and dark current cause photoresponse deviate actual value, the method measures every zero pixel gray value through fitting the Region of Interest of light field by Gauss curved surface. Then, calculate CCD sensitivity uniformity by the whole measured pixels normalization. The result is that ： for the CCD which is one of CCD47 - 10 series. The CCD sensitivity uniformity is 2.14%. The measure system can basically meet the requirement： reliable stability, high anti - interference and complete the measurement quickly and automatically.