菱体型消色差相位延迟器的光谱特性分析

Spectral characterization of the rhomb-type achromatic retarder

从全内反射相变方程出发,以菲涅尔菱体为例,分析了消色差相位延迟器的相位延迟量随折射率变化的光谱特性,结果表明:在所设计的中心波长处,延迟器件不仅仅局限于选择低色散的材料,色散较大的高折射率材料制作的延迟器件也可以具有良好的消色差性,且较大的全内反射角有利于改善延迟器件的消色差性.从而为优化菱体型相位延迟器的消色差性,扩大材料的选取范围提供理论指导.

Based on the total-reflection phase transformation theory of phase retardation, spectral characterization of the phase re-tardation varying with refractive index is analyzed, by means of the Fresnel rhomb. The result indicates that in the designed center of the wavelength, the retarder is not only confined within the low dispersive medium, but high-index material with higher disper-sion can also obtain good achromatism, and at the same time the bigger angle of total reflection can improve achromatism of the phase retarder. So the theoretical basis is provided for optimizing achromatism of the rhomb-type retarder and the material select-ing scope can be extended.