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. 04, 2020
Filed:
Nov. 22, 2017
Mitutoyo Corporation, Kanagawa, JP;
Hirokazu Kobayashi, Saitama, JP;
Osamu Kawatoko, Ibaraki, JP;
MITUTOYO CORPORATION, Kanagawa, JP;
Abstract
An encoder includes a light source. A booster circuit boosts a power supply voltage output by a battery, and outputs the boosted voltage. The voltage is applied to one end of a light-emitting diode. A driver circuit is inserted between another end of the light-emitting diode and a ground, the driver circuit controlling current flowing through the light-emitting diode. A voltage detector circuit detects a voltage between the light-emitting diode and the driver circuit. A control circuit causes the booster circuit to boost the power supply voltage when the voltage is lower than the power supply voltage; stops the boosting performed by the booster circuit when the voltage is equal to the power supply voltage; and controls the driver circuit such that, after the voltage reaches a predetermined value, current flows to the light-emitting diode.