可编程等效异形像元的几何超分辨方法

A geometrical super-resolution method of images based on programmable equivalent special shape pixels

为获得高分辨率目标图像,提出了等效异形像元几何超分辨方法。数字微镜器件(DMD)中2×2个微镜对应一个探测器像元,通过顺次控制DMD微镜编码得到4种异形像元,并采集各自状态下的目标图像,通过重建算法得到高分辨率目标图像。通过仿真实验验证了算法的有效性,并对视轴稳定误差对重建图像质量的影响进行分析。最后给出了像元尺寸、系统焦距与视轴稳定精度之间关系。实验结果表明:当探测器和目标之间不存在相对运动时,所得高分辨率图像PSNR可达53.024 3dB,相比于双线性插值方法提高了40.7%;可接受的探测器和目标之间最大相对运动量为1/10像元尺寸;当探测器像元尺寸为15μm、光学系统焦距为1 000mm时,系统对视轴稳定精度要求达到15μrad。所提出的方法可有效提高像元几何分辨率,且具有工程实现性。

In order to gain high-resolution image of the target,the use of DMD in detector pixel geometrical super-resolution method is analyzed in detail.Based on introducing spatial ligh t-modulation of DMD,the geometrical super-resolution method with equivalent novel pixels is given.In t his method,2×2micromirrors in DMD are arranged according to one detector pixel.Different micromirror codes are sent to DMD orderly to gain several novel pixels.With every novel pixel,the detector images the targe t.High resolution image could be gained by using reconstructing arithmetic.The effect of the given arithmetic is validated in the simulating experiment,and the effect of view-of-line stabilization error on reconstructe d image quality is analyzed.At last, the relationship between pixel dimension,optical focal and view-of-line stabi lization error is given.The simulating results show that the PSNR of the reconstruct ed h igh resolution image is 53.0243dB when there is no relative motion between detector and target,and the value is enhanced by 40.7% compared with that of image gained with bilinear interpolation method.The acceptable maximum relative motion between de tector and target is one tenth of the pixel dimension.The requirement of view-of-line stabilization error is 15μra d when pixel dimension is 15μm and optical focal is 1000mm.The proposed method could enhance th e pixel geometrical resolution effectively and could be realized in practice.