Share Email Print

Proceedings Paper

Modulated pitch phase gratings used in displacement encoder
Author(s): K. Hane
Format Member Price Non-Member Price
PDF $14.40 $18.00
cover GOOD NEWS! Your organization subscribes to the SPIE Digital Library. You may be able to download this paper for free. Check Access

Paper Abstract

The binary phase grating with the modulated pitch is investigated for a simple displacement encoder. The index grating consists of a binary phase grating to eliminate the zero-th order diffraction and the pitch of the grating is modulated to compensate the higher harmonics of the encoder displacement signal. Therefore, an undistorted sinusoidal signal as a function of displacement is obtained by simply superimposing a conventional binary amplitude scale grating on the modulated pitch phase gratings with any air gap between the gratings. The characteristics of the proposed gratings and the encoder signal are investigated by the Fresnel diffraction theory. The proposed grating was fabricated lithographically and the signal was examined experimentally. Considering these results, this method can reduce interpolation error and will be effective for an encoder in precision machining.

Paper Details

Date Published: 1 September 1996
PDF: 2 pages
Proc. SPIE 2778, 17th Congress of the International Commission for Optics: Optics for Science and New Technology, 2778F8 (1 September 1996); doi: 10.1117/12.2316237
Show Author Affiliations
K. Hane, Tohoku Univ. (Japan)

Published in SPIE Proceedings Vol. 2778:
17th Congress of the International Commission for Optics: Optics for Science and New Technology
Joon-Sung Chang; Jai-Hyung Lee; ChangHee Nam, Editor(s)

© SPIE. Terms of Use
Back to Top