Illumination control unit for display system with spatial light modulator
US5467146A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Mar 31, 1994 |
| Grant date | Nov 14, 1995 |
| Priority date | — |
| Expiry date | Mar 31, 2014 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N9/31
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
An illumination control unit (17) for a projection display system (10) that uses a digital mirror device (DMD) (15) to generate images. The illumination control unit (17) has a first set of lenses (23) for receiving light from a source and focussing the light to a color filter (24). A second set of lenses (25) receives the colored light and directs it to a prism (28). The prism (28) bends the light toward the reflective mirrors (30) of the DMD (15), and a collimating lens (28a) provides a beam that is approximately the size of the mirror array of the DMD (15). An optical shutter (26) is interposed between the second set of lenses (25) and the prism (28a), and permits the system (10) to achieve a "black state" between image displays or to achieve modulated brightness levels of images being displayed.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.