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:
May. 04, 1982
Filed:
Sep. 29, 1980
Akio Nakashima, Yokohama, JP;
Yoshimasa Okamoto, Yokohama, JP;
Hitachi, Ltd., , JP;
Abstract
A CRT drive circuit for amplifying a video signal applied through a video signal transmission cable to a level sufficient to drive a CRT wherein a circuit for clamping the video signal to a white level during the entire period when the cable is disconnected is provided at an input stage, a blanking circuit for clamping the video signal to a black level during a flyback period is provided in an intermediate stage, and a D.C. restore circuit for clamping the black level of the video signal output to a level corresponding to a black level input to the CRT is provided at an output stage. When the cable is disconnected, the entire display area of the CRT screen displays white so that the CRT drive circuit can be readily checked for proper operation.