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. 25, 2006
Filed:
Oct. 22, 2003
Hideaki Tamiya, Kanagawa, JP;
Kayoko Taniguchi, Kanagawa, JP;
Akihiro Kuroda, Kanagawa, JP;
Sony Precision Technology, Tokyo, JP;
Abstract
A displacement pickup is provided which includes a displaceable scale () having defined therein a first area () where positional information is recorded with a predetermined pitch and a second area () where positional information is recorded with a predetermined pitch different from that in the first area (), a first reading system () to read the positional information recorded in the first area (), a first phase detector () to detect a first phase on the basis of the positional information read by the first reading system (), a second reading system () to read the positional information recorded in the second area (), a second phase detector () to detect a second phase on the basis of the positional information read by the second reading system (), a phase comparator () to make a comparison between the first and second phases, and an origin signal generator () to generate an origin signal according to the result of comparison from the phase comparator ().