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. 08, 2003
Filed:
Dec. 21, 2000
Takashi Ueda, Kyoto, JP;
Rohm Co., Ltd., Kyoto, JP;
Abstract
The optical encoder according to the present invention comprises an optical unit and a light controlling member. The optical unit includes a light emitter for emitting light and a light receiver for receiving the light from the light emitter. The light controlling member includes a plurality of transparent portions for passing the light from the light emitter and a plurality of nontransparent portions disposed alternately with the transparent portions for blocking the light from the light emitter. The transparent portion and the nontransparent portion are so arranged that any pair of adjacent transparent portion and nontransparent portion has a constant length in a direction of the adjacency. The optical unit and the light controlling member are movable relative to each other in a direction of arranging the transparent and the nontransparent portions. The light receiver is provided with one or any greater number of light receiver groups each including a plurality of adjacent light receiving elements arranged in a direction of the relative movement between the optical unit and the light controlling member. Each light receiver group has, in said direction of the relative movement, a length which is unequal to said constant length of the adjacent transparent portion and nontransparent portion.