Abstract
This work presents three pixel circuits of transflective TFT-LCD. The concept of super patterned vertical alignment (S-PVA) and the structure of single cell gap are adopted in circuit design. With simple fabrication processes, the principle of pixel circuits is to match the operating voltages of liquid crystal in transmissive(T) and reflective(R) regions, respectively. Three proposed pixel circuits in this work can provide wide viewing angle and high image quality for panel.The first pixel circuit, composed of two TFTs, simplifies circuit elements and increases aperture ratio of pixel. The simulation result of this circuit has an error of 29 gray levels in the low gray level and an error of 25 gray levels in the middle gray level. The second pixel circuit, composed of three TFTs and additional two capacitors is used to improve the first pixel circuit. The simulation result has an error of 23 gray levels in the low gray level and an error of 24 gray levels in the middle gray level. Despite the error is large in the high gray level, the pixel in the high gray level is brighter, so human eyes can not identify the difference. The third pixel circuit has three TFTs, special wave driving method is used to control the voltage ratio between T and R regions, the simulation result is well matched to the characteristic curve, which means the error is minimized. The proposed circuits improve image quality and enhance luminating efficiency. These circuits will contribute to wide viewing angle applications in the future.
| Date of Award | 2009 |
|---|---|
| Original language | Chinese (Traditional) |
| Supervisor | Chih-Lung Lin (Supervisor) |