Oblique projection optical system
US6450648B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Jul 12, 2000 |
| Grant date | Sep 17, 2002 |
| Priority date | — |
| Expiry date | Jul 12, 2020 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG03B21/147
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
An oblique projection optical system performing enlargement projection in a slanting direction from a primary image plane to a secondary image plane, or reduction projection in a slanting direction from the secondary image plane to the primary image plane. The oblique projection optical system has at least two lens units each comprising at least one lens element and having surfaces decentered with respect to each other, wherein zooming is performed by moving, of said lens units, a plurality of lens units, and wherein when a ray connecting a center of the primary image plane and a center of the secondary image plane is referred to as an image plane center ray, the predetermined conditions are satisfied without an intermediate real image being formed between the primary image plane and the secondary image plane.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.