Device uses pattern of transparent contact touch points that are put on cathode ray tube screen. Touch point system compels more precise and unambiguous communication between man and machine than is possible with any other means, and speeds up operation responses

Rasmussen, H.

English

NASA Technical Reports Server

July 1971	 Brief 7I-10263 
.
NASA TECH BRIEF 
Manned Spacecraft Center 	
-4r 
NASA Tech Briefs announce new technology derived from the U.S. space program. They are issued to encourage 
commercial application. Tech Briefs are available on a subscription basis from the National Technical Information 
Service, Springfield, Virginia 22151. Requests for individual copies or questions relating to the Tech Brief program may 
be directed to the Technology Utilization Office, NASA, Code KT, Washington, D.C. 20546. 
Man-Machine Communication:
A Transparent Switchboard for Computers 
The ability of a computer to report information 
and for a man to respond quickly depend upon the con-
trol system. Conventional input controls use punch-
cards, paper or magnetic tape, light-pens and switches; 
conventional outputs are given by means of punch 
cards, written lists, magnetic tape, light bulb displays, 
paper tapes or cathode ray tubes (CRT). These are ade-
quate for most applications but a more direct dialogue 
results from a single man-machine interface. 
In a device designed for NASA, a pattern of trans-
parent contact "touch" points is put on a CRT screen. 
The computer-driven CRT displays information along-
side the contact points and the operator's touches are 
translated by low frequency capacitor couplings into de-
coding logic which tells the machine what points ,have 
been touched. 
An array of contact points is etched into a trans-
parent glass plate coated with tin oxide. This plate over-
lays the CRT. A touch on one of the contacts is related 
by electronic sensing circuits to the computer in the 
form of a logic compatible command. 
A tin oxide coating is used as the medium for the 
contact points because it bonds strongly to glass, is re-
sistant to mechanical use and chemical action, and is 
transparent in thicknesses up to 50 m.. The etching 
process is similar to that used in the production of cop-
per plated printed circuit boards. 
A touch point system compels a more precise and 
unambiguous communication between man and machine 
than is possible with any other means, and it speeds up
operation responses. Because the NASA system uses a 
low conductance frequency measurement a positive 
touch is needed. This precludes false inputs from an un-
steady operator's hand. 
Note:
Requests for further information may be directed 
to:
Technology Utilization Officer 
Manned Spacecraft Center, Code JM7 
Houston, Texas 77058 
Reference: TSP71- 10263 
Patent status: 
This invention is owned by NASA, and a patent 
application has been filed. Royalty-free, nonexclusive 
licenses for its commercial use will be granted by 
NASA. Inquiries concerning license rights should be 
made to:
Patent Counsel 
Mail Code AM 
NASA Manned Spacecraft Center 
Houston, Texas 77058 
Source: Hans Rasmussen 
Massachusetts. Institute of Technology 
under contract to
Manned Spacecraft Center
(MSC-13746) 
Category 02 
This documetct was prepared under the sponsorship of the National 	 Government assumes any liability resulting from the use of the 
Aeronautics and Space Administration. Neither the United States 	 information contained in this document, or warrants that such use 
Government nor any person acting on behalf of the United States 	 will be free from privately owned-rights.
https://ntrs.nasa.gov/search.jsp?R=19710000262 2020-03-17T02:21:00+00:00Z


Man-machine communication - A transparent switchboard for computers

Abstract

Similar works

Full text

Available Versions

NASA Technical Reports Server