EP 0411917 A1 19910206 - Security of video monitors.
Title (en)
Security of video monitors.
Title (de)
Sicherheit für Videomonitoren.
Title (fr)
Sécurité pour moniteur vidéo.
Publication
Application
Priority
GB 8917450 A 19890731
Abstract (en)
In order to prevent eavesdropping by detecting radiation given off by a video monitor dummy radiation is generated to disguise blank periods in the information. Also, the video information may be stored in order in alternating field stores 20, 22, and is read out from the stores under control of a random number generator 40, so that the lines of video information are displayed in random order on the cathode ray tube 62, but in the correct position.
IPC 1-7
IPC 8 full level
G09G 1/16 (2006.01)
CPC (source: EP)
G09G 1/165 (2013.01); G09G 2360/18 (2013.01)
Citation (search report)
- [X] EP 0240328 A2 19871007 - DATASAFE LTD [GB]
- [X] EP 0235947 A2 19870909 - INT COMPUTERS LTD [GB]
- [X] EP 0168861 A2 19860122 - NEDERLANDEN STAAT [NL]
Designated contracting state (EPC)
AT BE CH DE DK ES FR GB GR IT LI LU NL SE
DOCDB simple family (publication)
EP 0411917 A1 19910206; AU 6056290 A 19910311; GB 2237711 A 19910508; GB 8917450 D0 19901010; WO 9102344 A1 19910221
DOCDB simple family (application)
EP 90308448 A 19900731; AU 6056290 A 19900731; GB 8917450 A 19890731; GB 9001186 W 19900731