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:
May. 07, 1996
Filed:
Sep. 28, 1993
Hyung J Lee, Seoul, KR;
Byung T Kim, Kyungki-Do, KR;
Sejin Electron, Incorporated, Seoul, KR;
Abstract
This invention relates to methods of self-calibration for computer display cursor positioning devices imbedded within a computer keyboard key (sometimes referred to herein as a 'key-type mouse') or other pointing device. A plurality of Force Sensitive Resistor grids ('FSRs') or other pressure sensitive sensors are used to detect relative pressure applied in various directions to a predetermined key of a computer keyboard. An RC circuit is used to indirectly read the values of the FSRs. A predetermined delay period is associated with each sensor followed by a measurement period. The resistance of the FSR is related to the measurement period taken to reach a given voltage value after the predetermined delay period. A positive or negative offset to the predetermined delay period adjusts the time necessary for the RC circuit to reach a predetermined bias voltage value. By breaking the charging time into a delay period and a measurement period the amount of time that the keyboard controller or microprocessor must spend devoted to watching the voltage across the RC circuit for the moment when it reaches V.sub.CC is reduced, improving the operation of the keyboard.