Goudarzi Khouygani Mohammad Hossein, Jeng Jeng-Ywan
Appl Opt. 2020 Jul 1;59(19):5764-5771. doi: 10.1364/AO.393951.
This paper presents a novel optical encoder, M-encoder, which can be used within high-precision metrology systems based on the technology of customized prism and homodyne detection. The M-encoder is an exposed encoder measuring reflective glass and metal scale, which is targeting the biggest area of the encoder market, 20 µm pitch, and has a resolution under 100 nm. The error of 23 nm for 100 mm traveling distance has been measured. The applied technology has successfully improved alignment tolerances, in which the tolerance of installation achieved to ±0.5, ±0.5, and ±1 for pitch, yaw, and roll angle, respectively. The accuracy of results has been verified by comparing them with one of the commercial encoders and also by using an HP interferometer. The results show the resolution and accuracy can be compatible with the market products. In addition, a new method of grating calibration has been described based on the Littrow configuration, and the pitch of the fabricated scale by a femtosecond laser has been measured with the accuracy of 2 nm.
本文介绍了一种新型光学编码器——M编码器，它基于定制棱镜和零差检测技术，可用于高精度计量系统。M编码器是一种测量反射玻璃和金属标尺的外露式编码器，目标是编码器市场最大的领域，即20 µm节距，分辨率低于100 nm。已测量出100 mm行程距离的误差为23 nm。所应用的技术成功提高了对准公差，其中安装公差在节距、偏航和滚转角方面分别达到±0.5、±0.5和±1。通过将结果与一种商用编码器进行比较以及使用惠普干涉仪，验证了结果的准确性。结果表明，分辨率和精度可与市场产品相媲美。此外，还描述了一种基于 Littrow 配置的光栅校准新方法，并且已测量出飞秒激光制造的标尺节距，精度为2 nm。
