基于方向性模型的红外焦平面阵列混叠效应研究

Aliasing effect of the IR focal plane arrays based on angular-dependence model

提出一种定量评价红外焦平面阵列混叠效应的方法,这种方法基于采样传递函数和混叠效应的方向性,建立了焦平面阵列设计参数与混叠效应间的定量关系。利用此方法定量分析了矩形阵列和六边形阵列的混叠情况,结果表明:六边形阵列的混叠值较矩形高4%。完成了混叠效应对焦平面阵列任意方向上等效带宽的修正,进而分析混叠对其成像质量的影响,结果表明:当考虑混叠时,矩形阵列的成像质量较六边形高11%。

A method to determine the aliasing effects of infrared focal plane arrays was proposed, and specifically the aliasing value in each direction was determined based on the angular dependence of both sample transfer function and aliasing equation. The mean value as the aliasing value of the array was defined. Further, this model was used to calculate the aliasing value of the rectangular and hexagonal lattices of the same pixel, showing that the hexagonal lattice＇s aliasing value is higher by 4%. The equivalent bandwidth in each direction of the staring array was corrected allowing for the degradation caused by the aliasing effects. The image quality of rectangular and hexagonal lattices with aliasing effects was quantified, showing that the rectangular lattice in the sense of image-quality is superior to the hexagonal lattice by 11%.