液晶器件扭曲角与光延迟的光学外差法测试技术理论研究

Theoretical Research of Twist Angle and Optical Retardation Measurement of Liquid Crystal Display by Optical Heterodyne

将光学外差法应用于液晶器件扭曲角与光延迟的测试,提出了测试系统的光路简图,推导出了外差式测试方程,并对此方程进行了数值模拟与分析。此方法将液晶层的相位差转化为光学拍频信号的相位,由传统方法的测量光强转为测量拍频信号的相位差,能克服传统方法的缺点,因此具有较高的精度与抗干扰性。

A method of optical heterodyne was developed to measure twist angle and optical retardation of liquid crystal display in this paper. A schematic diagram of optical path was put forward, and formulas required in heterodyne were deduced. The numerical simulation and analysis of the formulas were also stated. The phase difference of liquid crystal cell is entirely converted to the phase of the beat signal. The phase difference of the beat signal was measured by simple optics in this method, other than light intensity in conventional methods. This heterodyne method can get rid of the drawbacks of conventional methods. Thus high precision and anti-jamming can be expected.