PC光学树脂计量圆光栅的制作

为了解决目前计量圆光栅的玻璃基片无法适应振动强度大、冲击力强等恶劣环境的问题,提出了采取新型材料聚碳酸酯(PC)来替代玻璃作为计量圆光栅制作基片的方法。分析了PC光学树脂的透光特性、耐热性和耐化学性能,给出了清洗PC的具体配方;结合现有光刻复制工艺,研制出先胶后铬的新型复制工艺;最后,以PC作为计量圆光栅基片,在蒸镀真空度为1.2×10-3Pa,蒸发距离为150mm的条件下,采用蒸发源质量控制膜厚的镀铬工艺参数,制作出了PC光学树脂基片的计量圆光栅。在45×显微镜下观察光栅线条,结果显示,线条陡直,无龟裂,表明该新型工艺可行,工艺参数正确,为进一步研制以PC光学树脂计量圆光栅为核心元件的精密测角仪器等提供了试验基础。

Manufacturing technology of PC optical resin metrological grating

To solve the problems that the glass base slices of metrological gratings can not suffer the bad environments such as strong vibration and big impact, a new type material,Polycarbonate(PC),was chosen to replace the glass to manufacture metrological gratings. The optical characteristics,light transmittance,heat tolerance and the chemical resistance of the PC were analyzed and a cleanout method for the PC was given. On the basis of traditional manufacturing of gratings, a new manufacturing technology,namely,coating first and vacuum plating Cr afterwards,was developed. Finally,by taking the PC as a base slice,a PC optical resin metrological grating was produced in the vacuum degree of 1.2×10^-3 Pa and evaporation distance of 150 mm, in which the film thickness was controlled by the quality of Cr. The PC metrological grating was observed in a 45× microscope.Results show that the edges of lines are vertical and no slips. The results indicate that the technology is feasible and technologic parameters are correct.It can provide an examination basis to develop precision measuring angle instruments.