Touch display to digital encoding system

• US 4,110,749 A
• Filed: 05/06/1977
• Issued: 08/29/1978
• Est. Priority Date: 05/06/1977
• Status: Expired due to Term

• Current Assignee: Tektronix Incorporated (Fortive Corp.)
• Original Assignee: Tektronix Incorporated (Fortive Corp.)
• Inventors: Silzars, Aris, Janko, Bozidar
• Primary Examiner(s): Trafton, David L.
• Application Number:
  US05/794,438
• Time in Patent Office: 480 Days
• Field of Search: 340/166 EL, 340/337, 340/365 R, 340/365 S, 340/365 C, 178/18
• US Class Current: 345/173
• CPC Class Codes: G06F 3/0488 using a touch-screen or digitiser, e.g. input of commands through traced gestures
• CPC Class Codes: H03K 17/962 Capacitive touch switches
• CPC Class Codes: H03K 17/98 having a plurality of control members, e.g. keyboard
• CPC Class Codes: H03M 11/20 Dynamic coding, i.e. by key scanning H03M11/26 takes precedence

Abstract

A system for inputting data into a display device by touch-sensitive contact areas disposed adjacent the display device and including state of the art electronic recognition circuitry associated with the contact areas for synchronously converting the data to discrete elements of information. Specifically, the transparent contact pads are overlayed over a display with each pad coupled with a multiplexer followed by a synchronous quadrature filter function performed by yet another multiplexer in such a manner that data displayed may be altered.

Claims

1. A touch display to digital encoding system, comprising:

display means including means for providing light images;

means associated with said display means for inputting N data units thereto, said means including a touch contact means sensitive to touching by a human body for providing N data units;

electronic recognition circuitry responsive to said N data units for synchronously converting said N data units to discrete elements of information to digitally encode said N data units, said circuitry comprising

(a) first means for selecting one out of said N data units and transmitting the selected data unit to a single channel, said first means including means for synchronously selecting said data unit;

(b) second means responsive to said data unit for providing a signal which is a synchronous rectified version of said data unit, said second means including unity gain amplifier means for rectifying said data unit;

(c) third means responsive to said signal for sychronously providing a filtered signal, said third means including synchronously switched means for filtering said signal;

(d) means for comparing said filtered signal and a reference signal to provide said discrete elements of information; and

means responsive to said discrete elements of information for providing control data, said means also being operatively associated with said display means for inputting said N data units thereto.

2. The system according to claim 1 wherein said display means is a cathode-ray tube and said means for providing light images is a viewing screen adapted to be responsive to said light images for providing a visually observable image.

3. The system according to claim 1 wherein said first means defines a multiplexer.

4. The system according to claim 1 wherein said third means defines a demultiplexer.