LED Display Optical Model-by-point Correction System

In the point by point color calibration process of the LED display, it is necessary to capture each LED lamp’s accurate optical data was required. In most widely used the point by point calibration system for the LED display, industrial camera was used to measure the optical data of LED lamp on the screen. As an imaging optical system, the collection direction is not likely facing each LED lamp’s optical axis direction, so the LED lamp’s brightness data collected by the system would be incorrect caused by the direction angle difference. Thus a LED display’s luminance attenuation model was required to correct the LED lamp’s brightness data.In this thesis, based on the theory of photometry, according to the LED lamp’s light distribution curve in the far field pattern, the LED lamp’s light intensity distribution function was obtained by fitting; and combined with the luminance distribution of the imaging optical system, deduced the light attenuation model of the LED display, then a3D coordinate system was built with the XY plane in the LED display screen, in which simulated the model and did the experimental verification, to prove the feasibility of the model. Taking care the outdoor calibration mode, the relevant parameters for the attenuation model could not be accurately measured, first used the low-pass filtering model to process the original light intensity data, after processing the data, then used the processed data to fit the parameter values required by the attenuation model, finally compare the fitting model with the actual model, and verified the method’s feasibility.