数字全息变焦系统测量液晶空间光调制器相位调制特性

Measuring phase modulation characteristics of liquid crystal spatial light modulator based on digital holographic zoom system

针对液晶空间光调制器(LC-SLM)应用于光信息处理等诸多领域的前提是必须准确测量出其相位调制特性曲线,本文利用全息干涉计量原理和数字全息变焦系统,提出了一种测量LC-LSM相位调制特性曲线的新方法,只需拍摄两幅数字全息图就能获得完整的相位调制特性曲线,并能够消除系统误差,从而降低对光学元件和调试精度的要求,且不需要完成衍射计算。介绍了相关的测量原理,给出了具体的实验测量过程、计算方法,实验结果表明,本文方法具有系统简单、可以消除系统误差和快速的优点。

Liquid crystal spatial light modulator（LC-SLM） has been widely used in many fields such as optical information processing,but it must to measure the phase modulation characteristics accurately.A new method for measuring the phase modulation characteristics of LC-SLM is proposed in this paper,in which the principle of holographic interferometry and the digital holographic zoom system are used.The phase modulation characteristics are calculated through two digital holograms,and at the same time the system error is eliminated,so the requirement of optical component adjustment precision is reduced,and the diffraction calculation is also omitted.The paper introduces associated measurement principle,presents the measurement process,calculation method and experimental results,and proves that the method has many advantages including simple system,low system error and fast measurement speed.