Image distortion correcting device and image distortion correcting method
US6989872B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jul 23, 2001 |
| Grant date | Jan 24, 2006 |
| Priority date | — |
| Expiry date | Dec 9, 2022 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N3/2335
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A write PLL circuit generates a write clock signal for writing a video signal into a line memory. A readout PLL circuit generates a read clock signal for reading out the video signal stored in the line memory. An inner pincushion distortion correction voltage generation circuit modulates a correction waveform in the horizontal scanning period of time by a correction waveform in the vertical scanning period of time, to generate an inner pincushion distortion correction waveform, and adds a DC correction pulse to the inner pincushion distortion correction waveform and outputs the inner pincushion distortion correction waveform as an inner pincushion distortion correction voltage. A capacitive coupling circuit superimposes the inner pincushion distortion correction voltage on an output voltage of a loop filter of the readout PLL circuit, and feeds the inner pincushion distortion correction voltage to a VCO as a control voltage.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.