Zhao Zixin, Xiao Zhaoxian, Zhuang Yiying, Zhang Hangying, Zhao Hong
State Key Laboratory for Manufacturing Systems Engineering, School of Mechanical Engineering, Xi'an Jiaotong University, Xi'an, Shaanxi 710049, People's Republic of China.
Institude of Systems Engineering, China Academy of Engineering Physics, Mianyang, Sichuan 621000, People's Republic of China.
Rev Sci Instrum. 2018 Aug;89(8):083116. doi: 10.1063/1.5031938.
This paper proposes a new interferometric method to measure the phase modulation characteristics of a liquid crystal spatial light modulator (LC-SLM). In our proposed method, the beam was incident perpendicular to the SLM and the combined grayscale pattern loaded into the SLM consisted of three parts. The left part was a blazed diffraction grating, and the two right parts were grayscale with different constant values. The gray value in the downward section remained constant at zero, while it gradually increased from 0 to 255 in the upward section. By changing the gray value of the combined grayscale loaded on the LC-SLM, different sheared fringe patterns, generated by the interference between the constant phase-modulated beam and the +1 order diffracted beam of the blazed grating, could be obtained. The phase modulation value could then be calculated using only one sheared fringe pattern. As a result, our proposed method can reduce the effect of environmental vibration or air turbulence and improve measurement precision. The experimental results are presented to validate the method's potential.
本文提出了一种新的干涉测量方法，用于测量液晶空间光调制器（LC-SLM）的相位调制特性。在我们提出的方法中，光束垂直入射到SLM上，加载到SLM中的组合灰度图案由三部分组成。左边部分是闪耀衍射光栅，右边两部分是具有不同恒定值的灰度图案。向下部分的灰度值保持为零不变，而向上部分的灰度值从0逐渐增加到255。通过改变加载在LC-SLM上的组合灰度图案的灰度值，可以获得由恒定相位调制光束与闪耀光栅的 +1 级衍射光束之间的干涉产生的不同剪切条纹图案。然后仅使用一个剪切条纹图案就可以计算出相位调制值。结果，我们提出的方法可以减少环境振动或空气湍流的影响并提高测量精度。给出了实验结果以验证该方法的潜力。
