Photographing lens
US6992840B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Dec 24, 2003 |
| Grant date | Jan 31, 2006 |
| Priority date | — |
| Expiry date | Dec 29, 2023 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG02B13/0095
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
A photographing lens includes an aperture stop having a predetermined aperture, a first lens having a positive refractive power and a convex surface facing the object side, a second lens having a positive refractive power and aspherical surfaces on both sides, the object-side aspherical surface being concave, and a third lens having a negative refractive power and aspherical surfaces on both sides, the object side surface being convex. The aperture stop and the first, second, and third lenses are arranged in order from the object side toward the image-plane side. With such a three-unit, three element lens configuration, a proper back focus is ensured, aberrations are properly corrected, and the total lens length and thickness of the photographing lens are reduced. The photographing lens can be suitably applied to high-resolution image pickup devices with a million pixels or more.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.