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:
Aug. 30, 2005
Filed:
Jul. 24, 2001
Applicants:
Nobuhiro Ishikawa, Tsukuba, JP;
Kiyokazu Okamoto, Tsukuba, JP;
Inventors:
Nobuhiro Ishikawa, Tsukuba, JP;
Kiyokazu Okamoto, Tsukuba, JP;
Assignee:
Mitutoyo Corporation, Kawasaki, JP;
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
H03D001/00 ;
U.S. Cl.
CPC ...
Abstract
Two all pass filters () with 90° phase-shifted different center frequencies are employed to pass an alternating signal S with jitters in the period to generate signals Sand S, 90° phase-shifted from each other. A pulse generator () generates a sampling pulse Sp by detecting a zero cross point of the phase-shifted signal S. A full-wave rectifier () rectifies full waves of the phase-shifted signal Sand provides a rectified output to a sampling circuit (), which extracts a peak value of the amplitude at the timing of the sampling pulse Sp.