Video display having progressively dimmed video images and constant brightness auxiliary images
US5386247A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jun 2, 1993 |
| Grant date | Jan 31, 1995 |
| Priority date | — |
| Expiry date | Jun 2, 2013 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N5/63
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
An on-screen display generator for use in an image display system is disclosed. The on-screen display generator includes a main image signal source, and an auxiliary image signal source which includes a controller for varying the perceived brightness of the image represented by the auxiliary image signal in response to a first control signal. A video signal processor, coupled to the main image signal source and the auxiliary image signal source, includes circuitry for combining the main and auxiliary image signals to produce a combined image signal. The video signal processor further includes a controller for varying the perceived brightness of the image represented by the combined image signal in response to a second control signal. A control signal generator generates the first and the second control signals in such a manner that the perceived brightness of the auxiliary image signal remains substantially constant when the perceived brightness of the main image is varied. This on-screen display generator is disclosed as being embodied in a sleep timer in a television receiver.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.