Projection display apparatus
US4787737A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Mar 16, 1987 |
| Grant date | Nov 29, 1988 |
| Priority date | — |
| Expiry date | Mar 16, 2007 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N9/3141
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A projection display apparatus includes a light source unit for generating light for image formation, an electro-optical display device for displaying an optical image by utilizing the light emitted from the light source unit, and an enlarging/projection lens. The light source unit, the display device, and the projection lens are accommodated in a housing with vent openings. The housing also includes a fan for cooling the interior of the housing with cool air and a cooler for maintaining a display panel within a predetermined temperature range. The light source unit includes a lamp and a reflector and is designed not to cause image deformation and formation of a shadow of a discharge portion. In order to display a television image on the display device, all television image display circuit units excluding an antenna are accommodated in the housing. The enlarging/projection lens can control a magnification and a focal point of the image projected on the screen.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.