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:
Oct. 22, 1991
Filed:
Mar. 22, 1990
Wacom Co., Ltd., Saitama, JP;
Abstract
An input/output apparatus includes a coordinate input device and a display device which are stacked on each other. The coordinate input device detects position coordinates of an input designating device by (a) intermittently transmitting radio waves from a tablet to excite a tuned circuit incorporated in the input designating device and (b) receiving radio waves generated by the tuned circuit while transmission of radio waves by the tablet is suspended. The times while the display data latch pulses are generated in the display device is synchronized with the transmission of radio waves from the tablet in the coordinate input device. In consequence, noise is not generated in synchronism with the generation of the display data latch pulses while the tablet receives the radio waves, so noise is not imposed on a signal received by the tablet. As a result, there is no reduction in the accuracy with which position is detected on the basis of the received radio waves and malfunction of the apparatus is substantially eliminated.