An electro-optical imaging system is a typical optical-discrete sampling system. Usually, the spatial resolution of the electro-optical imaging system can be improved by means of the technical routes such as the increase of objective lens focal length, the increase of detector array consumption, the size reduction of detector elements, and the increase of detector filling rate. Due to the restriction of device level,the effective data processing method can be used to improve the resolution of an imaging system. The sub-pixel imaging technique and the super-resolution image processing technique based on the discrete CCD/CMOS plane array detectors are mainly introduced, which are widely concerned at home and abroad.