Minimum image entropy technology applied to the real-time autofocusing system of space optical remote sensors

For space remote sensors with high resolution, large caliber, and long focal length, in-orbit automatic focusing technique is a significant application technology. Minimum image entropy (MIE) technology applied to real-time autofocusing system of space optical remote sensor possesses creativity and engineering significance. MIE's theoretical analysis, algorithm's computer simulation, and "Experimental Optical System" experiment have successfully validated MIE's validity as the criterion for optical remote sensor's auto-focusing. Related data indicate that for a diffraction-limited optical system with the f-ratio of F # = 39, the detecting sensitivity for checking-focus can be better than 0.1 mm, by means of MIE.