EP0305017A2
Expired / Lapsed
EP
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A television receiver having means for the suppression of line flicker
Assignee: Bang and Olufsen AS
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Filing: 1988-08-25
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Granted: —
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Expires: 2008-08-25
Abstract
Abstract In TV receivers line flicker occurs at horizontal transition or separation lines between a light and a dark picture area as reproduced in successive half pictures in respective positions mutually vertically displaced by one line width, whereby the separation line is jumping up and down. This is counteracted by a detector (18) continually detecting the distribution of the intensity of the video signal in an area vertically above and underneath the picture spot and producing a correction signal whenever a significant difference of intensity is detected. This signal is fed to or generated in a control unit (20) which affects the vertical deflector system (6) in a manner such that in one or both of the half pictures the line under reproduction will be displaced to such an extent that the said separation line in both of the half pictures will be reproduced in entirely or approximately the same geometrical height position on the screen, whereby the said jumping is eliminated or reduced.
Inventors
- 👤 Knud Erik Madsen
- 👤 Runo Rolighed Nielsen
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-03 01:58
CPC Classifications
H; H04; H04N; H04N7/00; H04N7/01; H04N7/0127; H04N7/0132
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
197 words
A television receiver having means for suppression of line flicker, such means comprising a detector unit for detecting a potentially line flicker producing operation of the receiver and a control unit, which, in response to such a detection, is operable to produce a correction signal to the vertical deflector system of the picture reproducing unit of the receiver, by which the line track of the picture spot is displaced upwardly or downwardly to a location near or nearer the line level of the corresponding neighboring line in the preceding half picture, characterized in that the detector unit is designed and arranged for continuous detection of the difference between the intensity of the actual video signal and the intensity of the video signal reproduced in a corresponding spot in at least one over- or underlying line in an interlace pattern on the screen, and in that the control unit is operable to produce the said control signal only in such situations in which it is detected by said detector unit that the picture spot is moved along a line portion forming a horizontal line of separation between over- and underlying picture areas of pronounced mutually different light intensity.
Claim 2
Dependent Claim
197 words
A television receiver having means for suppression of line flicker, such means comprising a detector unit for detecting a potentially line flicker producing operation of the receiver and a control unit, which, in response to such a detection, is operable to produce a correction signal to the vertical deflector system of the picture reproducing unit of the receiver, by which the line track of the picture spot is displaced upwardly or downwardly to a location near or nearer the line level of the corresponding neighboring line in the preceding half picture, characterized in that the detector unit is designed and arranged for continuous detection of the difference between the intensity of the actual video signal and the intensity of the video signal reproduced in a corresponding spot in at least one over- or underlying line in an interlace pattern on the screen, and in that the control unit is operable to produce the said control signal only in such situations in which it is detected by said detector unit that the picture spot is moved along a line portion forming a horizontal line of separation between over- and underlying picture areas of pronounced mutually different light intensity.
Claim 3
Dependent Claim
31 words
A receiver according to claim 1, characterized in that the control unit is designed so as to effect a dynamic line displacement towards the picture area of the higher light intensity.
Claim 4
Dependent Claim
108 words
A receiver according to claim 1, characterized in that the detector unit is additionally designed to be able to detect the situation that the picture spot is moved along a line portion, the light intensity of which is contrasting with the intensity in both the overlying and the underlying picture areas, and that the control unit is adapted to hereby effect a displacement of such a line portion less than a whole line width, preferably approximately half a line width upwardly in the one half picture and downwardly in the other for effecting an at least approximate merging of these line portions in the respective two half pictures.
Claim 5
Dependent Claim
34 words
A receiver according to claims 1 or 3, characterized in that the control unit is designed for effecting a line displacement of 0.6-0.9 of a line width, preferably approximately 2/3 of a line width.
Claim 6
Dependent Claim
67 words
A receiver according to claim 1, characterized in that the received video signal is fed to the reproduction unit through a delay and memory unit having a capacity corresponding to at least a single picture line, and that the detector unit is adapted to continually detect the intensity of the video signal along one or more lines preceding the actually reproduced line in the same half picture.
Claim 7
Dependent Claim
45 words
A receiver according to claim 1, in which the detector unit is operable to detect the intensity of the luminance signal in a graduated manner and the control unit is operable to effect a correspondingly graduated displacement of the line track of the picture spot.
Claim 8
Dependent Claim
39 words
A receiver according to claim 1, characterized in that the control unit in a receiver of the cathode beam type is connected with a small deflector coil, which is separate from the vertical deflector coil, but operating parallel therewith.
References Cited (Backward Citations)
No citation records indexed.
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