An electrically controlled smart window, which includes two transparent plates arranged oppositely, a power supply component and an in-between light-adjusting area. Hereinto the light-adjusting area is divided into a matrix of light-adjusting units by pixel wall(s), and every units are closely arranged in a grid shape. To the power supply component, an electrode is connected with the pixel wall, and another is localized on the center of light-adjusting unit and did with the transparent plate. Both surface-charged liquid crystal polymer particles and conductive packing fluid are filled into the medium between the two transparent plates. According to the present disclosure, cholesteric liquid crystal polymer microparticles with specific reflection band and surface charges are used as basic reflectors, thereby achieving the significant advantages of being easy to manufacture, low cost, and stable performance, without causing interference to electromagnetic signals.