影响制冷型中波红外焦平面探测器图像质量的因素主要包括响应的非均匀性、响应的漂移特性和盲元等。因此, 在红外焦平面成像系统中要进行实时的非均匀性校正、漂移补偿和盲元替代等信号处理。首先, 设计一套高帧频低噪声640×512像元的制冷型中波红外成像系统, 并进行动态范围标定, 实现其在全动态范围内NETD小于30 mK。接着, 针对焦平面像元的响应特性, 研究了适用于红外成像系统的非均匀性和盲元的校正方法, 提出了基于辐射定标和场景融合的非均匀校正、盲元检测及替代算法。最后, 进行外场红外图像数据采集。经实验验证, 其图像校正效果优良, 易于实现, 且具有较强的环境适应性。

The factors affecting the image quality of refrigerating medium wave infrared (MWIR) focal plane detectors include non-uniformity of response, drift characteristics of response and blind pixel. So signal processing in real time such as non-uniformity correction, drift compensation and blind pixel substitution is required in infrared focal plane imaging system. At first, a refrigerating MWIR image system with high frame frequency, low noise and 640×512 pixels is designed. And the dynamic range is calibrated to implement the NETD≤ 30 mK in full dynamic range. And then, according to the response characteristics of the pixels in the focal plane, the non-uniformity and blind pixel correction method suitable for the infrared imaging system are researched. A non-uniformity correction, blind pixel detection and substitution algorithm based on radiation calibration and scene fusion is put forward. At last, the infrared image data is collected in field experiment. Experimental results show that the method has a good image correction effect, easy to be implemented, and it has strong environmental adaptability.