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:
Dec. 07, 2004
Filed:
Jan. 23, 2001
Hidefumi Notagashira, Kanagawa, JP;
Canon Kabushiki Kaisha, Tokyo, JP;
Abstract
A coordinate input apparatus detects the accurate position of the diffuse light emitted by the light emitting unit of a pointer. The diffuse light emitted from the pointer is collected by a condenser lens, the amount of the diffuse light is detected by a control-signal detecting sensor with a high sensitivity, its output is detected by a frequency detecting unit, and a control-signal detecting unit detects a control signal. The diffuse light emitted from the pointer also passes through a visible-light-cut filter to remove disturbance light, and is received by linear sensors for detecting the direction in which the light comes. The linear sensors are controlled by a sensor control unit. The output signals of the linear sensors are converted by an A-D conversion unit provided for the sensor control unit, sent to a coordinate calculation unit, and the output coordinates on the sensors are calculated.