液晶空间光调制器用于波前校正的研究  

Wavefront correction using liquid crystal spatial light modulator

作　　者：张洪鑫[1,2] 张健[1] 吴丽莹[1] 向杰[1] 

机构地区：[1]哈尔滨工业大学超精密光电仪器工程研究所,黑龙江哈尔滨150080 [2]哈尔滨理工大学机械动力工程学院,黑龙江哈尔滨150080

出　　处：《红外与激光工程》2008年第6期1062-1065,共4页Infrared and Laser Engineering

基　　金：国家自然科学基金资助项目(60878048)

摘　　要：为了提高液晶空间光调制器用于波前校正的精度，测试了美国BNS公司反射式256×256像素纯相位液晶空间光调制器。由于非线性相位响应特性会降低该器件用于波前校正的性能，因此通过反插值法将相位调制曲线的非线性度减小到原来的1／8，建立了0～2π区间内相位与灰度之间的线性关系。以液晶空间光调制器作为波前校正器，数字相移干涉仪作为波前传感器，对含有高频误差的不规则波面进行了测量和误差校正。畸变波前的峰谷值（PV）由校正前的0．78A减小到校正后的0．27λ，均方根（RMS）由校正前的0．13A减小到校正后的0．02A。实验结果表明：液晶空间光调制器能够代替传统的变形镜，实现低成本、高分辨、高精度的波前校正。In order to improve the precision of wavefront correction using liquid crystal spatial light modulator（LC SLM）, the reflecting 256×256 pixels phase-only LC SLM from American BNS Corporation was tested. The nonlinear phase response of LC SLM can limit its application in wavefront correction. An inverse interpolation algorithm was established to reduce the phase nonlinearity to 1/8 of the original nonlinearity, and the linear relationship between phase and gray scale was established ranging from 0 to 2π. By using LC SLM as a wavefront corrector, and a digital phase shift interferometer as a wavefront sensor, an irregular wavefront with high frequency errors was measured and corrected. The results showed that the peak-to-valley value （PV） was reduced from 0.78λ before correction to 0.27λ after that, and the root means square value （RMS） was decreased from 0.13λ to 0.02λ. The experiment results indicate that the liquid crystal spatial light modulator can replace the traditional deformable mirror for its characteristics of low-cost, high-resolution, and high-precision wavefront correction.

关 键 词：波前校正 液晶 空间光调制器 相位调制特性 

分 类 号：TN761[电子电信—电路与系统]