System and method for on-site point-by-point calibration of brightness and chrominance of the whole screen of LED display screen

The invention discloses a system and a method for on-site point-by-point calibration of the brightness and chrominance of the whole screen of an LED display screen. The system comprises LED display screen optical parameter acquisition equipment, display screen calibration parameter processing equipment, display screen signal input control and parameter transmission equipment and display screen calibration operation and screen control equipment. The method comprises the following steps: acquiring image data of information on original red, green and blue values of a single point in the lightened part of the LED display screen and values of actual brightness and colors when single colors of red, green, blue and while are displayed; and determining the calibration coefficients of the single point to realize calibration. The method acquires data by in a way of uniformly distributing the luminous points of the display screen in arrays which have the same point number and shape and alternately distributed at equal intervals, thereby avoiding clear horizontal and vertical patterns which use an acquisition area as a unit and are caused by the jump of regional edge calibration data when an original suborigin acquires data and interference among adjacent points caused by reduced pixel pitch and ensuring the calibration effect.