微米孔阵列振幅型光子筛的设计和制作

在软X射线波段,各种材料的折射率均接近或小于1,常规的折射光学元件将无法使用,但是可以用光子筛等新型衍射光学元件实现软X射线波段的聚焦、成像和色散.光子筛具有体积小、重量轻、易复制和特殊的光学性能等优点,可以构成微型光机电集成系统(MOEMS),有效提高器件效能,降低成本,在军事、工业和民用等方面,应用市场潜力很大.综述了光子筛的国内外研究进展,介绍了光子筛的成像原理,根据标量衍射理论探讨了低数值孔径振幅光子筛的基本设计方法和制作工艺,给出了光子筛的计算机仿真结果,并且用激光直写方法在镀铬石英基片上刻蚀了特征尺寸为5 μm的微米孔阵列光子筛,实验测试了光子筛的成像性能.

Design and Fabrication of Low-Numerical-Aperture Amplitude-Photon Sieve

It is difficult to use a traditional refractive lens to focus soft x rays, because of the strong absorption of solid materials in this spectral region. However, photon sieve, which is a novel diffractive optical element consisting of a large number of precisely positioned holes distributed over a flat surface, can be used to the focusing and imaging of soft x rays. Photon sieve can be used as a part of MOEMS to improve the efficiency and lower the cost because it is small in size, light in weight, repeatable in manufacture as well as special optical performance. This new kind of MOEMS can be widely applied to martial, industrial, civilian and other fields. The imaging principle of photon sieve was introduced. The methods of design and fabrication of low-numerical-aperture amplitude-photon sieve were discussed, and the simulation results of photon sieve were presented, according to scalar diffraction theory. Laser-beam lithographic process was used to produce the photon sieve which feature size is 5um on a chrome-coated quarts plate. The imaging performance of the photon sieve was tested.