图像矩心内插法在空间相机实时检焦中的应用

自动检调焦技术是保证空间相机拍摄出高质量图象的重要技术手段,本文提出了一种自准直法精密检焦系统,该方法利用五棱镜代替大平面反射镜,用CCD作为光电转换器件,用半导体激光器做光源,结构紧凑,稳定可靠.采用矩心法求取光斑在CCD上的移动量,从而计算出离焦量,在测量中通过合理选取阈值和数据平滑技术,提高了检测精度,实验结果表明该方法能够达5μm以内的检焦分辨率

Application of centroid sensing method in real-time autofocusing system used in space camera

Auto-focusing technique is an important method for ensuring high quality image of space camera.In order to refocus in-flight for space camera,a precise auto-focusing system with auto-collimatic method is introduced, in which two pentagonal prisms are substituted for a large mirror,a low power laser is used as the light source and CCD as photoelectric converting device. This system has compact structure and reliable properties. The resolution of the whole measuring system has been improved by the use of signal processing techniques in centroid sensing method such as choosing threshold and data smoothing,the experiments show that the measuring resolution is less than 5μm.