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:
Feb. 26, 2002
Filed:
Feb. 08, 2000
Hirokazu Sakuma, Tokyo, JP;
Takashi Okamuro, Tokyo, JP;
Yoshimitsu Sato, Tokyo, JP;
Toshiro Nakashima, Tokyo, JP;
Hajime Nakajima, Tokyo, JP;
Mitsubishi Denki Kabushiki Kaisha, Tokyo, JP;
Abstract
An interference-type distance measuring device generates a reference beam having a first frequency and detection beam having a second frequency and directs these beams toward a moving detection unit which reflects these beams toward an interference system, where these beams are used to generate a detection interference wave. A reference interference wave generated by the interference system is converted into a first sine-wave signal, the interference detection wave is converted into a second sine-wave signal, first and second cosine-wave signals are generated from the first and second sine-wave signals, and the position of the motion detection unit is detected based upon these four signals.