用衍射效率比测浮雕矩形光栅参量

Determining the Relief Rectangular Grating′s Parameters with the Diffraction Efficiencies Ratio

基于矩形光栅的标量衍射效率公式,提出一种根据0级和1级衍射效率比来测量浮雕矩形光栅的刻槽深度和折射率的方法,并对衍射效率与刻槽深度和入射角的关系进行分析.对刻槽深度分别为2.90,1.01μm的熔石英离子刻蚀矩形光栅进行测量,从实验上验证测量方法的正确性.研究结果表明:通过测量透过光栅的0级和1级衍射光强比,可反演出矩形光栅刻槽深度和塑料光栅材料的折射率,所测量光栅刻槽深度和折射率的误差均小于1%.

Based on the scalar diffraction efficiency formula,a new method of measuring the relief grating groove depth and the refractive index using the diffraction intensity ratio of the zero-order and the first-order is proposed.The relationship between diffraction efficiency and groove depth as well as angle of incidence was analyzed.By measuring the groove depth of 2.90 and 1.01 μm of fused silica ion etching rectangular grating,experimentally verified the correctness of the measurement method.The results show that the rectangular grating groove depth and,the refractive index can be determined by measuring the diffraction intensity ratio of zero-order and first-order and the relative error is less than 1%.