Projection zoom lens and optical projector provided with the same
US6985302B2 · kind B2 · utility
Assignee
Inventor
Key dates
| Filing date | Jan 28, 2004 |
| Grant date | Jan 10, 2006 |
| Priority date | — |
| Expiry date | May 20, 2024 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG02B15/145527
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
A projection zoom lens comprises a first lens group having a negative refracting power and including a single meniscus lens having an aspherical surface facing an object surface, a second lens group having positive refracting power and including a single second-group lens, a third lens group having negative refracting power and including a compound lens, a fourth lens group including a single fourth-group lens, and a fifth lens group having positive refracting power and including a single fifth-group lens. The fifth lens group is kept stationary, and the first, the second, the third and the fourth lens group are shifted on the optical axis toward the screen to increase the magnification of the projection zoom lens.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.