Gamma-correction circuit for blue color video signal in projection television
US6137543A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Dec 19, 1997 |
| Grant date | Oct 24, 2000 |
| Priority date | — |
| Expiry date | Dec 19, 2017 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N9/69
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
The present invention relates to a gamma-correction circuit which can prevent the deterioration of focusing in a projection television. The gamma-correction circuit comprises a gamma-correction section having an input for receiving a blue color video signal and operable to generate a gamma-corrected signal, a peak-beam current limiting section connected to the gamma-correction section and operable to compare a beam current corresponding to the blue color video signal with a predetermined peak-level value, the peak-beam current limiting section further operable to clip or pass the gamma corrected signal according to the comparison, and a video amplifying section connected to the peak-beam current limiting section and operable to amplify clipped or passed signal, and output the amplified signal to a blue color CRT.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.