斜入射液晶空间光调制器的特性

Oblique-Incidence Characteristic of Parallel-Aligned Nematic-Liquid-Crystal Spatial Light Modulator

用读出光斜入射到液晶空间光调制器(LC-SLM)的读出面,是一种有效的提高空间光调制器(SLM)读出效率的方法。测量了读出光以不同角度入射到液晶空间光调制器的读出面上时,相位调制深度与写入光强的关系、衍射效率与二值光栅对比度的关系。得到随着入射角度的增加,最大相位调制深度减小,而衍射效率变化并不明显。在45°时有最大相位调制深度2.0936π和35.4%的正一级衍射效率。

It is a valid way to improve the read-out light efficiency of spatial light modulator that the incident readout light obliquely enters the read-out plane of the liquid crystal spatial light modulator. With different incident angles, the relations of the phase modulation depth and the write-in light intensity and of the diffraction efficiency and the contrast of the binary grating are measured. It is found that, with increasing incident angle, the maximum depth of the phase modtalation decreases＇ but obvious change of the diffraction efficiency does not occur. With 45°incident angle, the maximum depth of the phase modulation reaches 2. 09367t, and the positive first order diffraction efficiency is 35.4%.