Image-forming optical system
US6771427B1 · kind B1 · utility
Assignee
Inventor
Key dates
| Filing date | Jan 14, 2002 |
| Grant date | Aug 3, 2004 |
| Priority date | — |
| Expiry date | Jan 14, 2022 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG03B21/28
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
A luminous flux, from one conjugate surface (A), having an opening angle of at least 10° sequentially passes through a first optical system (30) having a luminous flux convergent action in the vicinity of its reference axis and a second optical system (31) having a luminous flux divergent action in the vicinity of its reference axis, and converges on another conjugate surface (B). A specific condition is given to the converging distance of each converging point at a luminous flux section including a principal ray according to the passing position of the luminous flux through the first optical system (30) to thereby implement an oblique-incident optical system having a half angle of at least 60° and a comparatively simple structure irrespective of a type of an optical element used.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.