紫外全息闪耀光栅的制作

通过理论计算研究了影响闪耀光栅衍射效率的因素,并利用离子束刻蚀模拟程序模拟刻蚀闪耀光栅来确定闪耀光栅的制作参数。以理论计算的闪耀光栅参数为依据,以刻蚀模拟程序为指导,基于全息-离子束刻蚀工艺制作了闪耀波长分别为250nm和330nm,光栅尺寸分别为85mm×85mm,60mm×60mm,线密度均为1200lp/mm的闪耀光栅。第一种光栅闪耀角为8.54°,非闪耀角为72°,其250nm波长自准直入射时的-1级衍射光衍射效率约为81%;第二种光栅闪耀角为11.68°,非闪耀角为74°,330nm波长自准直入射时的-1级衍射光衍射效率约为80%。实验结果表明,提出的方法可以在制作闪耀光栅的过程中实现对闪耀角的精确控制,获得的实验结果与理论计算结果符合较好。利用该方法能够在大尺寸基底上获得衍射效率75%的紫外闪耀光栅。

Fabrication of ultraviolet holographic blazed grating

The factors effecting on the diffraction efficiencies of blazed gratings were researched and the parameters fabricating the blazed gratings were determined by holographic ion beam etching. On the basis of above, two kinds of blazed gratings with a line density of 1200 lp/mm and blazed wavelength of 250 nm and 330 nm were fabricated, respectively, and then their blazed angles were measured by a Atomic Force Microscopy(AFM) and the diffraction efficiencies were measured by a plane grating diffraction efficiency instrument. Obtained results show that the 250 nm blazed grating with a size of 85 mm×85 mm has a blazed angle of 8.54°and a right angle of 72° and its diffraction efficiency is about 81% at 250 nm. Moreover, the 330 nm blazed grating with a size of 60 mm×60 mm has a blazed angle of 11.68°and a right angle of 74° and its diffraction efficiency is about 80% at 330 nm. These data demonstrate that experimental results are well in agreement with that calculated ones and illustrate that blazed angles can be controlled in grating fabrication process. By using the proposed method, the ultraviolet blazed gratings with diffraction efficiency more than 75% can be fabricated on a large size substrate.