EP0237174A2
Expired / Lapsed
EP
⏱️ 0.0 years remaining
Device for displaying wide-aspect images on a non-wide-aspect screen
Assignee: British Broadcasting Corp
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Filing: 1987-02-03
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Granted: —
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Expires: 2007-02-03
Abstract
Abstract A cathode ray tube video display device is adapted to display wide aspect ratio signals by reducing the vertical scanning amplitude of the scanning raster. The scan is collapsed in the vertical direction without reducing the number of lines used to display the active picture, leaving unscanned bands at the top and bottom of the display. The device can change between a normal raster scanning mode and such a collapsed wide screen mode automatically in response to an indicator in the received video signal.
Inventors
- 👤 John Philip Chambers
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-10-24 13:25
CPC Classifications
H; H04; H04N; H04N7/00; H04N7/01; H04N7/0117; H04N7/0122; G; G01; G01R; G01R13/00; G01R13/20; G01R13/22; G01R13/24; H04N7/015
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
95 words
A cathode ray tube (CRT) video display device for displaying pictures with a raster of horizontally-scanned lines, including a CRT, and scanning means for the CRT operable in a normal mode of operation in which the scanning raster covers the whole display to display a picture of normal aspect ratio, and in which the scanning means is also operable in an alternative mode to display a picture of larger aspect ratio, in which alternative mode the vertical scanning amplitude of the raster is reduced relative to the height of the display in the normal mode.
Claim 2
Dependent Claim
95 words
A cathode ray tube (CRT) video display device for displaying pictures with a raster of horizontally-scanned lines, including a CRT, and scanning means for the CRT operable in a normal mode of operation in which the scanning raster covers the whole display to display a picture of normal aspect ratio, and in which the scanning means is also operable in an alternative mode to display a picture of larger aspect ratio, in which alternative mode the vertical scanning amplitude of the raster is reduced relative to the height of the display in the normal mode.
Claim 3
Dependent Claim
34 words
A CRT display device according to claim 1, including means responsive to an indicator included in a received video signal to cause the scanning means to switch automatically to the alternative mode of display.
Claim 4
Dependent Claim
32 words
A CRT display device according to claim 1 or 2, in which in the two scanning modes the vertical extent of the scanning raster is centred at substantially the same horizontal point.
Claim 5
Dependent Claim
14 words
A broadcast television receiver incorporating a CRT display device in accordance with claim 1.
References Cited (Backward Citations)
No citation records indexed.
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