液晶取向层微双折射的测量研究

The Measurment of Small Birefringence in PI of Liquid-Crystal

用旋转检偏器和锁相放大器测量圆偏振光经过样品(双折射片)后其偏振态的微小改变,进而测得样品的相延量δ,测量标准偏差为10^(-2)nm。

The possibility of different measurements of small birefringence (about 10^(-2) rad) is discussed theoretically, experimentally by comparison, and the device of high precision(10^(-2) nm) is performed. Using the rotating polarizor and lock-in amplifier, we detect the small change of the polarization states of the light passing the birefringent sample. To test the device, we use Solid compensator whose linearity and homogeneity is not very good to measure the stability of the system. Further more, We measure the retardation δ which is proportional to the tense exerted on the optical-elastic material, and get the linearity index and precision of the device. Finally, We look into the future of making instrument and application.