Abstract
In this paper, a theoretical model is presented for the display process of uniformly-arranged virtual-pixel LED displays with RGBG sub-pixel structure cells. Such displays' modulation transfer function (MTF) is derived theoretically from this model. Experiments were conducted to validate the theoretical model to measure the MTF of virtual-pixel displays and traditional real-pixel displays with a pixel pitch of 0.9 mm. A dual-line spread function measurement method is proposed, which is experimentally shown to be more effective than the conventional single-line LSF measurement method in measuring the MTF of LED displays. The rationality of the theoretical model was analyzed and compared through experiments. Furthermore, a combined subjective and objective evaluation method for the image quality of LED sub-pixel displays is proposed, which analyses the effect of LED sub-pixel multiplexing on the display clarity based on the square root integration method and achieves the subjective goal of quantifying the LED display quality. The research results reveal the theoretical and experimental aspects of virtual-pixel displays and may have practical significance for the design of high-quality LED displays.