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. 24, 1998
Filed:
Jan. 22, 1996
Yoshihiro Yanagisawa, Atsugi, JP;
Yuko Morikawa, Kawasaki, JP;
Hiroshi Matsuda, Isehara, JP;
Haruki Kawada, Yokohama, JP;
Kunihiro Sakai, Isehara, JP;
Hisaaki Kawade, Atsugi, JP;
Ken Eguchi, Yokohama, JP;
Eigo Kawakami, Ebina, JP;
Toshimitsu Kawase, Atsugi, JP;
Minoru Yoshii, Tokyo, JP;
Kenji Saitoh, Yokohama, JP;
Akihiko Yamano, Yokohama, JP;
Hiroyasu Nose, Zama, JP;
Canon Kabushiki Kaisha, Tokyo, JP;
Abstract
An encoder includes an electrically conductive reference scale having surface steps formed at predetermined positions; an electrically conductive probe having a tip disposed opposed to the reference scale; wherein the reference scale and the probe are relatively movable in a direction different from the opposing direction of the tip of the probe and the reference scale; a portion for applying an electrical voltage to between the reference scale and the probe; a portion for detecting a change in a tunnel current between the reference scale and the probe, to between which the electric voltage is applied by the voltage applying portion at the time of the relative movement between the scale and the probe, the detecting portion detecting the change in the tunnel current when the probe passes a position opposed to a surface step of the reference scale; and portion for detecting the amount of the relative movement between the scale and probe, on the basis of the detection by the change detecting portion.