Study And Implementation Of Gray Controls For Asynchronous Pseudo Color LED Display Screen

LED panel screen, composed by LED dots matrix, plays more and more important role in the media of advertisement, because of the improvement of light intension, the advancement of the LED craftwork technology and the drop of the price. In recent years, LED panel screen has developed from displaying single text format information to showing mixed dynamic pictures. This article prepares the system design of the indoor asynchronous pseudo color LED display and the hardware implementation of the gray-grade scanning based on the analyses on gray-grade display.A great of study has spent on the gray-grade display principles of the bi-color LED display based on the irradiance mechanism of LED with the property of visual acuity. In asynchronous LED display system, the picture displayed is created in the software set up in PC, then the linear transformation and theγrectification in order to accord with the eye visual property, prepared before displayed, will be validated in the LED display screen. A new scheme of image data storey with SDRAM based on the FPGA is proposed. The hardware implementation of the control mechanism for SDRAM is described in detail.