Active-Matrix Thin-Film Transistor Liquid-Crystal Displays

Abstract

Publisher Summary Despite their recent emergence, liquid-crystal displays (LCDs) are widely used and are expected to replace many of the older displays in many applications, because of their unusual combination of low power consumption, thin structure, light weight, and low cost. This chapter discusses LCDs based on thin-film transistor (TFT) elements, commonly called as “TFT LCDs.” It also describes the material aspects of TFT elements, their performance characteristics, design, structure, and the operation of complete TFT LCDs. The electrical driving schemes used and the application areas of these displays are also presented in the chapter. In the active-matrix approach, a suitable active circuit element is incorporated at each pixel to overcome the limitation of direct-drive multiplexing. These active elements can consist of thin-film field-effect transistors or diode elements. The active-matrix concept effectively helps to achieve high contrast ratio and wide viewing angle along with large number of scan lines. Moreover, the active-matrix approach allows images to be produced with a much better grey scale than is possible with direct-drive multiplexed operation.