Lens system and image observation apparatus
US11874448B2 · kind B2 · utility
0Cited by
8References
8Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Aug 28, 2019 |
| Grant date | Jan 16, 2024 |
| Priority date | — |
| Expiry date | Sep 26, 2040 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG02B27/02
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
Proposed is a lens system capable of providing, to a user, a high-definition image in which generation of concentric circles is reduced. The lens system has one or more Fresnel lenses. A lens surface of each of the Fresnel lenses has a plurality of grooves that is concentrically formed. Both a pitch which is the distance between two adjacent grooves and the depth of each of the plurality of grooves vary with the distance from an optical axis that passes through the center of the lens system.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.