Illumination system and projection device
US-2024231212-A9 · Jul 11, 2024 · US
Projection optical system and image display apparatus
US8950874B2 · US · B2
| Field | Value |
|---|---|
| Publication number | US-8950874-B2 |
| Application number | US-201213611578-A |
| Country | US |
| Kind code | B2 |
| Filing date | Sep 12, 2012 |
| Priority date | Sep 16, 2011 |
| Publication date | Feb 10, 2015 |
| Grant date | Feb 10, 2015 |
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- Title
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Abstract
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A projection optical system for use in an image display apparatus having an illumination optical system applying light from a light source, and an image display device receiving the light from the illumination optical system to form a projection image includes a projector lens composed of plural lenses, a first mirror, and a second mirror formed of a concave mirror. The projection optical system is configured to project the projection image onto a projection surface. A projection luminous flux passing through the projector lens to be incident on the first mirror is a luminous flux exhibiting divergence. The projection luminous flux reflected off the second mirror after having reflected off the first mirror is converged once, and the once converged projection luminous flux is projected onto the projection surface. A lens surface of a lens located closest to the first mirror among the lenses of the projector lens is convex.
First claim
Opening claim text (preview).
What is claimed is: 1. A projection optical system for use in an image display apparatus having an illumination optical system configured to apply light emitted from a light source, and an image display device configured to receive the light applied from the illumination optical system to form a projection image, the projection optical system comprising: a projector lens composed of a plurality of lenses; a first mirror; and a second mirror formed of a concave mirror, the projectio…
Assignees
Inventors
Classifications
- G03B21/2066Primary
Physics · mapped topic
- G02B17/08Primary
Physics · mapped topic
Physics · mapped topic
Physics · mapped topic
Physics · mapped topic
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Frequently asked questions
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- What does patent US8950874B2 cover?
- A projection optical system for use in an image display apparatus having an illumination optical system applying light from a light source, and an image display device receiving the light from the illumination optical system to form a projection image includes a projector lens composed of plural lenses, a first mirror, and a second mirror formed of a concave mirror. The projection optical syste…
- Who is the assignee on this patent?
- Tatsuno Hibiki, Ricoh Co Ltd
- What technology area does this patent fall under?
- Primary CPC classification G03B21/2066. Mapped technology areas include Physics.
- When was this patent published?
- Publication date Tue Feb 10 2015 00:00:00 GMT+0000 (Coordinated Universal Time) (B2). Legal status and post-grant events are not shown on this page.
- What related patents are in patentsdb?
- We list 8 related publications on this page (citations in our corpus or others sharing the same primary CPC).