考虑填充率下亚像元与过采样成像MTF对比

针对探测器存在填充率时过采样和亚像元成像质量评价问题,利用亚像元算法反演线阵探测器像元扩散函数,发现较过采样成像不仅能在1/m微扫描作用下减小采样间隔,还能使探测器矩形窗口压缩m倍.根据MTF和一阶过零频率概念,得到同一填充率下亚像元较过采样对欠采样成像改善程度要大,且随着填充率的提高该优势愈加趋于明显.对比评价对实际亚像元算法成像的前景和优势给与理论上的肯定.

Contrast MTF Between Sub-Pixel Arithmetic and Over-Sampling Imaging Considering Filling Rate

In order to model the estimation for the over-sample and sub-pixel imaging considering the detector's filling rate,the detector pixel spread function is derived adversely by the sub-pixel arithmetic.Compared to the over-sample imaging under the 1/m micro-scanning,not only is the sample distance reduced but also the rectangle size of cell detector is compressed to 1/m of the original after the process of sub-pixel arithmetic.Based on the definition of MTF and first-zero frequency,image improvement using sub-pixel arithmetic is larger than the over-sample transform under the same filling rate,and this predominance is boosted up when the filling rate increases.This conclusion in comparison gives evidences in theory for the prospective and advantage of sub-pixel arithmetic imaging.