制冷焦平面高动态范围热成像非均匀校正系数与积分时间的关系

Relationship between Integral Time and Two-point Non-uniform Correction for HDR Imaging of Cooled Focal Plane Array

变积分时间是实现高动态范围(HDR)热成像的最有效手段,但积分时间的变化会使得系统的残留非均匀性噪声也发生变化。从红外系统响应模型出发,推导了两点非均匀校正(NUC)法的增益和偏置校正参数与积分时间的关系,结果表明:增益校正参数与积分时间无关,只有偏置校正参数与积分时间有关;并通过实际热成像系统的测试对比实验,证明了上述结论的正确性。研究结果为变积分时间的HDR热成像系统的NUC提供了合理、可行的校正依据,可极大的简化变积分时间的HDR热成像系统NUC处理过程。

Variable integral time is an effective means to realize the high dynamic range （HDR） of infrared system.Unfortunately,it would lead to serious residual non-uniformity.The relationship between the correction parameters （gain and offset） of two-point non-uniform correction （NUC） and integral time is derived based on the infrared system response model.The result shows that the gain parameters are independent of integral time,and only the bias parameters change with integral time.The correctness of the above conclusions is confirmed by testing it against standard two-point NUC method.The result can provide a reasonable evidence for NUC of infrared system with variable integral time,which only updates the offset parameters but maintain same gain parameters.