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:
May. 12, 1998
Filed:
Jan. 22, 1996
Atsushi Ieki, Kani, JP;
Okuma Corporation, Gifu, JP;
Abstract
An optical encoder comprising a first scale and photo sensitive elements that shift relative to the first scale along the length of the first scale for determining a relative position based on a plurality of signals having a predetermined phase difference from the photo sensitive elements. The optical encoder comprises groups of photo sensitive elements, wherein each group comprising a plurality of photo sensitive elements arranged side by side in the direction of the length, and wherein each photo sensitive element has a width corresponding to the width of the pattern of the first scale. The groups of photo sensitive elements corresponds respectively to the plurality of signals. The photo sensitive elements belonging to one photo sensitive element group and the photo sensitive elements belonging to the other photo sensitive element group are arranged side by side in a mixed fashion in the direction of the length. One photo sensitive element group and the other photo sensitive element group are arranged so that the signal derived from the one photo sensitive element group and the signal derived from the other photo sensitive element group have a predetermined phase difference therebetween.