3707715 is referenced by 13 patents and cites 4 patents.

A data input device comprises a single cathode ray tube whose screen is divided into a plurality of zones. Each zone is scanned with a pattern characteristic of a corresponding code by means of a code matrix. Each pattern excites a zone of the screen to display a corresponding alphanumeric or other symbol with an intensity sufficient to excite a photodetector, which provides an output signal indicative of the code corresponding to a zone when this zone is at least partially obscurated, for increasing the luminous intensity of the character on the screen.

Title
Data input device
Application Number
05/107,718
Publication Number
3707715
Application Date
January 19, 1971
Publication Date
December 26, 1972
Inventor
Perotto Pier Giorgio
Assignee
Ing C Olivetti & C
IPC
G08b 05/36
H03K 17/969
H03K 17/94
G06F 03/23
G06F 03/33
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