多通道宽响应域TDI CCD成像系统的非均匀性校正

发布时间：2018-03-27 22:25

本文选题：成像系统　切入点：非均匀性校正　出处：《光学学报》2017年11期

【摘要】：针对时间延迟积分(TDI)电荷耦合器件(CCD)成像系统多通道间存在响应非均匀问题,开展了基于辐射定标的校正方法研究。结合成像系统的信号处理流程,推导了响应非均匀性校正的理论模型,提出了一种基于加权最小二乘的定标校正方法,分别在1/4、1/2和3/4饱和响应处采集三组图像数据,并利用高斯加权函数对三组通道间的校正参数进行加权最小二乘拟合,从而获得优化的校正参数。利用TDI CCD成像系统进行实验验证,结果表明,系统的响应非均匀性(1/2饱和响应处)由原来的4.09%降低至0.85%,并优于两点校正法的1.93%,同时该方法在宽响应域内均获得了良好的校正效果,具有精度高、实用性强等特点,可应用于机载、星载等相机载荷,为获取高质量的遥感图像数据奠定技术基础。
[Abstract]:In order to solve the problem of nonuniform response between multiple channels of time delay integral TDI (TDI) charge-coupled device (CCD) imaging system, the correction method based on radiometric calibration is studied, which is combined with the signal processing flow of the imaging system. A theoretical model of response nonuniformity correction is derived, and a calibration method based on weighted least squares is proposed, in which three sets of image data are collected at 1 / 4 / 1 / 2 and 3 / 4 saturation response, respectively. The optimized correction parameters are obtained by using Gao Si weighting function to fit the correction parameters between the three groups of channels by weighted least squares. The experimental results of TDI CCD imaging system show that, The response nonuniformity of the system is reduced from 4.09% to 0.85%, which is better than that of the two-point correction method (1.93%). At the same time, the method has good correction effect in wide response domain, and has the characteristics of high accuracy and strong practicability. It can be applied to airborne, spaceborne and other camera payloads, which lays a technical foundation for obtaining high quality remote sensing image data.
【作者单位】：中国科学院长春光学精密机械与物理研究所;中国科学院大学;
【基金】：国家973计划(2016YFB0501202)
【分类号】：TN386.5

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