温度与微结构高度误差对衍射光学元件衍射效率的影响研究

基于衍射光学元件的衍射效率与微结构高度误差的关系,提出了环境温度、微结构高度误差与衍射效率和带宽积分平均衍射效率的数学分析模型。研究了环境温度变化对带宽积分平均衍射效率的影响,分析了工作在一定温度范围内时带宽积分平均衍射效率与相对微结构高度误差的关系。对于工作在8~12μm长波红外波段的衍射光学元件,偏离设计波长越远,其衍射效率受温度的影响越大。温度的变化会引起100%衍射效率对应的峰值相对微结构高度误差发生改变。当衍射光学元件的相对微结构高度误差在±15%范围内时,衍射效率在-40℃~80℃的整个温度范围内高于91.89%,带宽积分平均衍射效率在整个温度范围内高于88.58%。

Research on the Influence of Temperature and Microstructure Height Erroron Diffraction Efficiency for Diffractive Optical Elements

Based on the relationship between diffraction efficiency and microstructure height error for diffractive optical elements(DOEs),mathematical analytical models of environment temperature,microstructure height error,and diffraction efficiency/polychromatic integral diffraction efficiency(PIDE)were put forward.The influence of ambient temperature on the PIDE was researched and the relationship between the PIDE and microstructure height error within a certain temperature range was analyzed.For a DOE working within an 8-12μm long-waveband infrared range,the influence of temperature on the diffraction efficiency was significant as the wavelength deviated from the designed value.The peak relative microstructure height error corresponding to the 100%diffraction efficiency changed with the change of temperature.When the relative microstructure height error of the DOE was within±15%,the diffraction efficiency was higher than 91.89%in the temperature range from-40℃ to 80℃ and the PIDE was higher than 88.58%in the entire temperature range.