Patent · US Expired

Ultrasonic coordinate input apparatus

US5637839A · kind A · utility

75Cited by
0References
20Claims
0Family size

Assignee

Inventors

Key dates

Filing dateDec 29, 1994
Grant dateJun 10, 1997
Priority date
Expiry dateDec 29, 2014

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10S367/907
  • WIPO fieldComputer technology
  • WIPO sectorElectrical engineering

Abstract

An ultrasonic coordinate input, apparatus comprising a plurality of ultrasonic wave receivers to receive ultrasonic wave emitted by a cordless ultrasonic pen and propagating in an ultrasonic propagating medium, a plurality of receiving circuits for detecting the rising edges of received signals of the ultrasonic wave receivers, a measuring circuit for measuring the difference in time of receiving ultrasonic wave between the ultrasonic wave receivers and a calculating circuit for calculating the coordinates of ultrasonic wave input position according to the result of measurement. When the receiving circuits, the measuring circuit and the calculating circuit are installed together with the ultrasonic wave receivers on the ultrasonic propagating medium, the entire apparatus can be made small in size.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.