Two measurement methods are proposed in this thesis. Firstly, A modified crystal rotation method is developed. Such idea will much reduce the measurement time from several minutes to few milliseconds. More than the short acquisition time, that modified method does not require any rotation or movement of the test cell. Such features make the modified setup able to install on the production line intrinsically for real time measurement access....[ Read more ]

Two measurement methods are proposed in this thesis. Firstly, A modified crystal rotation method is developed. Such idea will much reduce the measurement time from several minutes to few milliseconds. More than the short acquisition time, that modified method does not require any rotation or movement of the test cell. Such features make the modified setup able to install on the production line intrinsically for real time measurement access.

Secondly, A completely new Pretilt angle measurement method using synthesized retardation compensator is proposed. Due to the rapid development of Liquid Crystal Display, the parameters configuration of liquid crystal display now becomes very critical and extreme. For some sort of pi-Bi-stable Twist Nematic Cell, its cell gap requires less than 1.5um and, also in order to further reduce the states inter-switching voltage, high Pretilt angle are favorable. It is known that it is rather difficult to measure pretilt angle using Crystal Rotation Method under such extreme case. Therefore, a new method for such extreme case is proposed. It makes use of a synthesize compensator combination (QHQ) to record the retardation of the liquid crystal cell. After simple calculations are undertaken, the Pretilt angle in such critical case can be obtained. It also requires no cell gap information too.