基于图像清晰度检测的光栅刻划平台调平装置

Grating ruling platform leveling device based on image clarity measurement

针对制备衍射光栅时刻划平台倾斜导致的光栅槽型误差,提出了一种基于图像清晰度检测与电动倾斜台调节的光栅刻划平台在线调平装置。建立了图像清晰度与光栅刻划平台倾角间关系的模型,应用该模型,控制光栅刻划平台在一定范围内实现了闭环动态调平。对上述理论研究进行了试验验证。试验结果表明,该调平装置简单可行;对于50mm×50mm的光栅毛胚,调平装置可控制刻划平台的水平倾角在4″以内,满足光栅刻划对平台定位精度的要求。该装置既可用于刻划前的调平准备,也可推广应用于光栅刻划过程中的实时检测。

To reduce the grating groove errors caused by the inclination of a grating ruling platform in the fabrication of diffractive gratings this paper proposes a real-time leveling device for the grating ruling platform based on image clarity measurement and electrically adjusting a tilting table.A physical model was built based on the inclination relations between the image clarity measuring and the inclination angle of grating ruling platform.Based on the model,the leveling device could control the grating ruling platform to implement the closed loop dynamic leveling within a certain range.The above theory was verified by tests.The results show that the leveling device is simple and feasible.For a grating blank with a size of 50 mm×50 mm,it controls the inclination of the grating ruling platform to be within 4″,meeting the requirements of the grating ruling for platform positioning accuracy.Moreover,the leveling device can be used in leveling before ruling and also in ruling processing in real time.