Last year, we introduced a TFT‐LCD with RGBW color system. The primary advantage of the RGBW system is that its optical efficiency is at least 50% higher than the RGB system. However, it is not a simple task to incorporate the new color system into the existing infrastructure of the RGB system: the driving circuitry, fabrication of color filter, and color conversion. In this report, the practical hurdles are discussed and the solutions are presented.

In this paper, we propose a compensation method for variations in the subthreshold slope (SS) and threshold voltage (Vth) of the low-temperature polycrystalline silicon thin-film transistors (LTPS TFTs) in an attempt to improve the image quality of the active matrix organic light-emitting diode (AMOLED) displays for mobile applications. The proposed compensation method provides a uniform voltage to the OLED according to the gray level without being affected by variations in the SS and Vth of the LTPS TFTs. To verify the performance of the proposed compensation method, a test pattern, including two pixel circuits designed for 5.7-inch quadruple high-definition AMOLED display was fabricated and measured. The measurement results showed that the proposed compensation method achieved an emission current error of the pixel circuit of only ±3.1 LSB at the 255 th gray level. Therefore, the proposed compensation method is very suitable for AMOLED displays requiring high image quality.INDEX TERMS Thin film transistors, organic light-emitting diode displays, pixel circuit, high image quality.

We propose a new LCD mode named as Charge-Pumped Super Patterned Vertical Alignment (CP S-PVA) which can utilize 1G-1D driving. In this mode, the voltage difference between two subpixels is controlled by a unique charge-pumped structure. This results in equal level of off-axis image quality and transmittance to TT S-PVA. Moreover, this new mode has good production yield and production margin. Operation schemes and display performance of CP S-PVA are presented.

A simple and cost‐effective vertical alignment mode, named Smart Viewing Angle(SVA) mode, for active‐matrix (AM) LCDs was developed where all the domain dividers are fabricated only on the TFT substrate side. The crucial component is the director control electrode (DCE) under the openings of the pixel electrode. The DCE maintains higher voltage than that of the pixel electrode via additional TFTs, which distorts the electric field in such a way that stable domain division is accomplished. Compared to the conventional VA modes where the additional process is required, SVA mode can achieve the wide viewing angle without any additional processes.