The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jul. 25, 2000
Filed:
May. 17, 1996
Applicant:
Inventor:
Atsushi Ieki, Gifu, JP;
Assignee:
Okuma Corporation, Nagoya, JP;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
G02B / ; G01B / ; G01B / ; H01J / ;
U.S. Cl.
CPC ...
359569 ; 359575 ; 2502 / ;
Abstract
An encoder has the capability of outputting a stable displacement signal with small distortion. The encoder includes a first scale and a second scale. The first or second scale has a scale pattern in which pattern elements are arranged in such a manner that the spacings between adjacent pattern elements are not constant but vary in phase relative to the reference phase of a reference pattern element by amounts of P/(2.multidot.L), P/(2.multidot.m), P/(2.multidot.n), P/(2.multidot.o), . . . (L, m, n, o, . . . are positive integers, P is the mean pattern period) and by amounts of combinations of sums of these values.