超低频全息光栅的制作与频率选控

Fabrication of ultra-low frequency holographic grating and control of spatial frequency

针对超低空间频率(f<20mm-1)的特殊要求,提出利用平板分振幅法制作低频全息光栅的新思路。该方法光路简单,使用器件少,性能稳定。通过对大量实际光栅样品的测量,详细研究了光栅常数和空间频率的特性。利用线性规划和指数拟合对数据进行分析,得到光栅常数(空间频率)-实验参数的定标方程。基于该定标方程,提出了控制全息光栅空间频率的精确方法。

For the scope of ultra- low spatial frequency （f 〈 20mm^- 1 ）, a new method of making holographic grating is presented by using flat - splitting amplitude method. The method is simple, stable and need less apparatus. Based on the measurement of a great deal of grating samples, properties of raster constant and spatial frequency are researched in detail. Utilizing linear regression and exponential decay fit, formulas of raster constant （spatial frequency） - experimental parameter are derived. Furthermore, a method to precisely control the frequency of grating is presented with the above calibration equations.