Oblique projection optical system and projection type display apparatus using the same
US8690349B2 · kind B2 · utility
6Cited by
4References
15Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Apr 10, 2013 |
| Grant date | Apr 8, 2014 |
| Priority date | — |
| Expiry date | Apr 10, 2033 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T29/49995
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A projection type display apparatus including an oblique projection optical system having a plurality of lenses is disclosed. A lens nearest to a projection screen has a vertical effective image area through which a light flux passes. The lens is arranged at a position not including an optical axis shared by the largest number of lenses among the plurality of lenses. A flat mirror for returning the optical path is arranged between the particular lens and the projection screen at a predetermined angle to the optical axis. An enlarged image obtained by the light flux returned by the flat mirror is formed toward a display screen.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.