No abstract

Reflective color LCDs with high image quality, which have very low power consumption when displaying still images and can also display moving pictures, have been developed. Two key technologies are Memory‐in‐Pixel (MIP) fabrication using LTPS technology, and another is optical property optimization by adopting a newly‐developed scattering layer.

In this paper, the performance of a new RGBW reflective display for mobile devices is described, including high reflectance and wide color gamut. In addition, a newly developed 7‐inch WUXGA (1200 times 1920) prototype reflective color LCD using a new RGBW technology is described.

A 3.9" microLED display prototype with LTPS backplanes has been developed by using a newly-designed current and PWM hybrid driving technology to lower the color shift, resulting in achieving a higher frame rate. A novel approach for a reflector cavity process for improving outcoupling efficiency was also proposed.

-A 7.03-in. extended graphics array reflective LCD prototype has been developed by using memory-in-pixel (MIP) technologies with a newly designed system and pixel structure. The MIP system comprising a MIP backplane and a display driver has been optimized to reduce power consumption. The MIP backplane has specific circuits that allow accessing row drivers randomly, and the display driver manages which row should be accessed. Thus, the system is capable of showing a mixture of still and moving images, resulting in low power consumption. A dithering block embedded in the display driver enables to select an appropriate dithering algorithm according to the types of images and the position on the screen. In addition, the novel pixel structure, "three divided patterns", has been designed to improve image quality and to provide visibility in dark environments. The latter is based on a novel approach; interpixel area is used for an aperture to transmit light from the backlight, and the fringe field from adjacent pixel electrodes is used to control LC directions. The feature of the pixel structure is also effective for obtaining equivalent gamma between reflective and transmissive images.