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:
Mar. 08, 1977
Filed:
May. 28, 1975
Yutaka Tochitani, Musashino, JA;
Takashi Shinbata, Musashino, JA;
Yoshitsugu Morioka, Musashino, JA;
Yokogawa Electric Works, Ltd., Tokyo, JA;
Abstract
A graphic display device of the type which receives data and instructions from an external computer and displays graphic patterns such as alphanumeric characters, symbols, etc., upon a cathode ray tube in accordance therewith. The graphic display device has a pattern generator for storing luminance data controlling the formation on the cathode ray tube of predetermined patterns, and a refresh memory for receiving and storing data designating the particular arrangement of patterns to be displayed, and is characterized by an arrangement reducing the required capacity of the pattern generator memory. Pursuant to the invention, the pattern generator is formed with a random access memory into which data can be written and from which data can be read, and has means operated on a time sharing multiplexing basis with data reading operations for writing luminance data supplied by the external computer into the pattern generator memory, and for storing in the refresh memory the addresses of the luminance data written into the pattern generator memory. The pattern generator need store formation data for only those characters actually being displayed on the cathode ray tube, and memory requirements are minimized.