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:
Apr. 12, 2005
Filed:
Nov. 10, 2003
Hideaki Tamiya, Kanagawa, JP;
Kayoko Taniguchi, Kanagawa, JP;
Eiko Kanbara, Kanagawa, JP;
Sony Precision Technology, Inc., Tokyo, JP;
Abstract
A displacement pickup is provided which comprising a scale () having defined thereon a first area () where positional information is recorded with a predetermined pitch and a second area () where positional information is recorded with a pitch different from that in the first area (), a first reader () which reads the positional information recorded in the first area (), a first phase detector () which detects a first phase on the basis of the positional information read by the first reader (), a second reader () which reads the positional information recorded in the second area (), a second phase detector () which detects a second phase on the basis of the positional information read by the second reader (), a phase comparator () which makes a comparison between the first and second phases, and an origin signal selector () which produce a plurality of signals according to the result of comparison and selects an arbitrary one of the plurality of signals on the basis of the positional information read by the first reader ().