A low-cost high-resolution active and passive single-pixel imaging optical-
mechanical system comprises an 
imaging lens, a rotary table, a transmitting part, a receiving part and a 
data processing system. The 
imaging lens is a commercial astronomical 
telephoto lens; according to the emitting part, a 
laser device and an emitting light path are stably fixed to the front end of an 
imaging lens in the mode that a fixing ring and a fixing frame are matched, a 
laser beam passes through two 45-degree reflectors on the emitting light path, then is coaxial with the imaging lens and is emitted to a target, illumination is provided by 
laser during active imaging, illumination is provided by ambient light during 
passive imaging, and the imaging efficiency is improved. And closing the laser. And the receiving part is quickly mounted at the rear end of the imaging lens through threads on the interface nut. The problems that a customized high-resolution optical 
system is high in development cost, long in period and complex in 
system structure in single-pixel imaging, and the period and cost are additionally increased in 
functional development of pointing, focusing and the like are solved, a single-pixel imaging optical-
mechanical system is assembled on a commercial large-aperture astronomical 
telescope, and the active-passive integrated imaging function is achieved.