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:
Jun. 01, 1993
Filed:
Feb. 24, 1992
Hidejiro Kadowaki, Yokohama, JP;
Ken Tsuchii, Tokyo, JP;
Makoto Takamiya, Kawasaki, JP;
Kosuke Yamamoto, Yokohama, JP;
Masafumi Wataya, Kawasaki, JP;
Toshiyuki Yanaka, Tokyo, JP;
Haruhiko Takahashi, Yokohama, JP;
Hiroshi Sugiyama, Yokohama, JP;
Yasuhiko Ishida, Tokyo, JP;
Canon Kabushiki Kaisha, Tokyo, JP;
Abstract
A Doppler velocity meter has a radiation source for emitting a radiation beam the wavelength of which fluctuates, such as a laser; an optical system for directing the radiation beam to an object at an incident angle .theta. and a detector for detecting scattered beam generated from the object by directing the radiation beam. The optical system has a diffraction grating which serves to change the incident angle .theta. in accordance with a change in the wavelength .lambda. of the radiation beam in such a manner as to maintain the value of sin .theta./.lambda. substantially constant. The velocity meter can accurately detect the velocity of movement of the object regardless of any change in the wavelength .lambda., because the diffraction grating serves to substantially compensate for any change in the frequency of the scattered beam caused by the change in the wavelength.