Projection system featuring light source luminuous flux sensing and compensation
US7425932B2 · kind B2 · utility
Assignee
Inventor
Key dates
| Filing date | Jul 11, 2003 |
| Grant date | Sep 16, 2008 |
| Priority date | — |
| Expiry date | Oct 7, 2024 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N9/3194
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A projection system having a projection display (20), at least one light source (10), and a sensor means for sensing and compensating for changes in the luminous flux emitted by the at least one light source (10) is described. The sensor means comprises in this case at least one sensor arrangement (30; 31, 32; 33, 34) for sensing components (M) of the light from the light source (10) that are directed into a region surrounding an entering face of an optical component (11) of the projection system. It has been found that there is a very good correlation between these components (M) of the light from the light source (10) and those other components (I) of the light that actually reach the projection display (20), which means that by controlling a power supply unit (10c) for the light source (10) and/or a driver unit (20a) driving the projection display (20) in a suitable manner it is possible very effectively to suppress fluctuations in brightness that occur as a result of, for example, unstable arc discharges.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.