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. 02, 2000
Filed:
Sep. 09, 1997
Yasuhiko Ishida, Tokyo, JP;
Naoki Kawamata, Utsunomiya, JP;
Canon Kabushiki Kaisha, Tokyo, JP;
Abstract
An angular division apparatus for circumferentially dividing a rotating object into a plurality of areas by using Doppler pulses includes an optical head for applying a beam emitted from a light source unit to a rotating object and detecting Doppler pulses based on a shift of the frequency of the light scattered from the rotating object, and a counting unit for counting the Doppler pulses output from the optical head to determine the number of pulses for one revolution of the rotating object. The number of Doppler pulses for one revolution is divided by a division number for dividing the rotating object into a plurality of areas in the angular direction. The rotating object is divided into a plurality of areas in the angular direction thereof by using the number of Doppler pulses per divided area.