The development of a diffraction-type four-degrees-of-freedom sensor based on the three-dimensional diffraction method and collimation method is described in this paper. This sensor is designed to be integrated with a linear laser encoder to allow five-degrees-of-freedom measurement. It is composed of a miniature collimation-type sensor, a reflective diffraction grating and a quadrant detector to simultaneously measure a straightness error and three rotational angles. Based on the diffraction method, the reflective diffraction grating reflects the incident laser from the collimation-type sensor to several diffractive laser rays and only the 0 and +1-order diffractive laser rays are detected by the collimation-type sensor and a quadrant detector respectively. According to the changed spot positions of the diffraction laser lights on the collimation-type sensor and the quadrant detector, a straightness error and the three rotational errors can be solved simultaneously.
Chien-Hung Liu Wen-Yuh Jywe Chao-Kuang Chen W.H.Hsien Lih-Horng Shyu Liang- Wen Ji Van-Tsai Liu Tung-Hui Hsu Chih-Da Chen
Graduate Institute of Electro-Optical and Materials Science, National Formosa University, Taiwan, Ch Institute of Mechanical and Electro-Mechanical Engineering, National Formosa University, Taiwan, Chi Department of Mechanical Engineering, National Cheng Kung University, Tainan,Taiwan, China, 701 Department of Electrical Engineering, National Formosa University, Huwei,Taiwan, China, 632 Department of Mechanical Engineering, National Chung-Cheng University, Chiayi,Taiwan, China Institute of Mechtronoptic Systems, Chien Kuo University of Technology, Changhua,Taiwan, China, 500
(0)