With the increase in resolution of mobile phones, aperture rate of panel is getting lower and lower, in order to maintain the luminance required to meet consumers' needs, the luminance of the backlight needs to be continuously enhanced, but the problem brought by enhancing the backlight brightness is the power consumption of backlight is getting larger and larger, and the product's battery life is reduced. One technology solution to solve this problem is to adapt a pixel unit structure with four sub-pixels in a display apparatus, that is, each pixel unit includes a red sub-pixel R, a green sub-pixel G, a blue sub-pixel B, and a white sub-pixel W. Comparing to the conventional pixel unit, this structure adds the white sub-pixel W, by using color resist material of transparent material having a more than 99% transmittance, increasing the transmittance of each pixel unit as a whole, thereby the number of light sources in the backlight can be reduced, and the backlight power consumption has also been significantly reduced.
However, the actual display of the display apparatus is more often a color image, such as a character, scenery or the like. In this case, since ¼ region is occupied by the white sub-pixel W in the RGBW pixel structure, and the luminance of the backlight is low, the color (R+G+B) image is presented a certain degree of darkness, besides, due to the presence of the white sub-pixel W will cause the appearance of color to be diluted, such as dark red to light red, which is the display quality of the RGBW pixel structure product need to be improved.