Color video projection system employing reflective liquid crystal display device
US6661475B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Mar 23, 2000 |
| Grant date | Dec 9, 2003 |
| Priority date | — |
| Expiry date | Mar 23, 2020 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N9/3167
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
An image projector (8, 68) includes a light source (14) that illuminates a three-path reflective LCD assembly (25, 74) that produces images for projection by a projection lens (27). The light source produces S-polarized light rays that are received by a spectrally selective wave plate (36) that changes a first wavelength range of light to P-polarized light rays (34) and transmits without polarization change second and third wavelength ranges of light. A plate-type transflective polarizing beam splitter (40) transmits the P-polarized first wavelength range light rays and reflects S-polarized second and third wavelength range light rays (34). The P-polarized first wavelength range light rays transmit through a field lens (421) and impinge on a first reflective LCD light valve (261). The S-polarized second and third wavelength range light rays strike a pleochroic filter (48), which divides them into second and third wavelength range light rays (44, 46) that propagate through field lenses (422, 423) and impinge on respective second and third LCD light valves (262, 263). The light rays impinging on dark state pixels on the first LCD light valve are reflected without polarization directi…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.