Electric lamp and discharge devices: systems – Cathode ray tube circuits – Cathode-ray deflections circuits
Patent
1982-07-12
1983-12-20
Blum, Theodore M.
Electric lamp and discharge devices: systems
Cathode ray tube circuits
Cathode-ray deflections circuits
315 13C, H01J 2970, H01J 2976
Patent
active
044220197
ABSTRACT:
An apparatus of providing vertical smoothing of convergence correction signals in a digital convergence system is disclosed. The surface of a cathode ray tube is subdivided into a matrix including a plurality of intersecting rows and columns and having a plurality of intersections corresponding thereto. A value is assigned to each intersection of a row and a column of said matrix. An electron beam traces a plurality of scan lines within each of the rows of the matrix. For each scan line within a row of the matrix, a convergence correction signal is synthesized using the plurality of values associated with the plurality of intersections in said row. A plurality of horizontal discontinuities are present in the convergence correction signal as a result of the different magnitudes associated with the plurality of values used to synthesize the convergence correction signal. Using conventional filtering techniques, the impact of the horizontal discontinuities in the convergence correction signal may be minimized thereby providing horizontal smoothing of the convergence correction signal. When the electron beam begins tracing the plurality of scan lines in the next, subsequent row of the matrix, a vertical discontinuity is produced, i.e., a gap or an overlap between groups of scan lines traced by the electron beam. The impact of these vertical discontinuities can be minimized by providing vertical smoothing of the convergence correction signal. This vertical smoothing is accomplished by using a linear interpolator to interpolate between values associated with two adjacent, vertically oriented intersections of said matrix, and by progressively changing the magnitude of the convergence correction signal in response thereto. Vertical smoothing of the convergence correction signal is accomplished and the vertical discontinuities between groups of scan lines traced by the electron beams are eliminated.
REFERENCES:
patent: 4316211 (1982-02-01), Mackey et al.
patent: 4354243 (1982-10-01), Ryan et al.
Blum Theodore M.
Bouchard John H.
Jones Allston L.
Tektronix Inc.
LandOfFree
Apparatus for providing vertical as well as horizontal smoothing does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Apparatus for providing vertical as well as horizontal smoothing, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Apparatus for providing vertical as well as horizontal smoothing will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-109603