10.6μm激光器一级输出高衍射效率闪耀光栅的研制

Manufacture for High Diffraction Efficiency Grating in the First-order Output of 10.6 μm Laser

建立了实际刻划光栅的物理模型,给出了相应的衍射效率表达式,并研制出了在Littrow安装下一级衍射效率达到97.2%的大功率10.6μm红外激光器用反射式闪耀光栅。实际刻划光栅通常都存在零级面,采用傅里叶分析方法可以推导出计算带有零级面的闪耀光栅衍射效率的一般表达式,由理论分析可知,零级面是造成闪耀光栅衍射效率下降的原因之一。在工艺过程中,通过加大刻划负载使零级面减小,加大侧向压力强化对闪耀面的抛光等,是提高光栅刻槽质量和衍射效率的有效途径。

The physical model of real ruled grating is purposed, the corresponding expression of diffraction efficiency is given, and reflecting blazed grating, which is fixed on the 10.6 μm IR laser with 97.2 percent in the first order diffraction efficiency in Littrow form, is made. There is the zero-order plane in the real ruled grating. We can deduce the general expression of diffraction efficiency of the blazed grating with the zero-order plane by Fourier analysis method. According to the theory analysis we can conclude that the zero-order plane is one of all the reasons that cause decrease in the diffraction efficiency of the blazed grating. In the process of technology, it is an effective method for increasing groove quality and diffraction efficiency that increasing ruled load making the zero-order plane decrease and enhancing lateral pressure intensifying politure to blazed plane.