Title:
INCREMENTAL OPTICAL ENCODER
Document Type and Number:
WIPO Patent Application WO2001018492
Kind Code:
A9
Abstract:
An incremental optical encoder (10) for measuring angle of rotation or linear displacement of a movable member and for determining the direction of such movements comprises a light source (11a) emitting a light beam along an optical path, an encoder plate (20), secured to the movable member, provided with a series of opaque zones and light transmissive zones (18A, 18B) arranged so as to cross the optical path and to modulate the light beam upon movement of the encoder plate, and a plurality of light detectors (A, B) arranged for generating output signals in quadrature upon movement of the encoder plate. The light detectors are arranged in separated and inter-digitated detector arrays and in at least two channels. A reticule (24) is located between the detectors and the encoder plate, and a detent structure establishes a gap between the reticule and the encoder plate.
Inventors:
BARNETT DONALD E
LEUNG ALLAN
LEUNG ALLAN
Application Number:
PCT/US2000/024368
Publication Date:
November 21, 2002
Filing Date:
September 05, 2000
Export Citation:
Assignee:
AMERICAN PREC IND INC (US)
International Classes:
G01D5/347; (IPC1-7): G01D5/347
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