红外多光谱相机的图像串扰校正方法

一种红外多光谱相机在1.55~2.35μm的波长区域有两个波段,由于探测器位于同一焦平面基底上以及读出电路设计等的影响,两谱段间存在串扰现象.首先对图像的串扰现象进行了描述,并对产生串扰现象可能的机理进行了分析.其次,从Hg Cd Te探测器焦平面阵列的内部结构及探测器的关键参数入手分析了光通过在焦平面区域的多次反射来进行反射及传输是光串扰及电串扰的机理;同时读出电路不准确设计也导致了串扰现象,并对串扰现象进行数学建模.研究发现B10波段的串扰(负/正冲激)与B11波段的阶跃(上升/下降沿)相关.最后基于所创建的数学模型对串扰现象进行了校正.

Image crosstalk correction method of the infrared multispectral camera

There are two bands in the wavelength of 1.55-2.35μm region for the infrared multispectral camera. Due to the detectors being located on the same focal plane assembly and the design of the readout circuits, one band was found to have crosstalk from other band. Firstly, the crosstalk phenomenon in the infrared multispectral camera image was described and the mechanism of crosstalk phenomenon was investigated. Secondly, based on the aspects of the inner structure of the HgCdTe detector's focal plane array and some important parameters of the detector, it was found that light is reflected and transported by multiple reflections in the focal plane area, which was mechanism of optical and electrical crosstalk phenomenon. Meanwhile, the readout circuits' inaccurate design could also lead to crosstalk phenomenon. Mathematical model was built based on crosstalk phenomenon. The research shows that the crosstalk phenomenon (negative/positive pulse) of B10 is relevant to the step (ascending/descending edge) of B11. At last, the crosstalk math model is validated and relevant correction algorithm is developed.