Imaging lens with high resolution and short overall length
US7408723B1 · kind B1 · utility
Assignee
Inventor
Key dates
| Filing date | Nov 28, 2007 |
| Grant date | Aug 5, 2008 |
| Priority date | — |
| Expiry date | Nov 28, 2027 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG02B13/004
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
An exemplary imaging lens includes, in this order from the object side to the image side thereof, a first lens of positive refraction power, a second lens of negative refraction power, a third lens of positive refraction power, and a fourth lens of negative refraction power. The imaging lens satisfies the formulas of: (1) 1<T/F<1.29; (2) R3/F>15 and (3) R7>0, R6<0, where T is the overall length of the imaging lens, F is the effective focal length of the imaging lens, R3 is the radius of curvature of the object-side surface of the second lens, R6 is the radius of curvature of the image-side surface of the third lens, and R7 is the radius of curvature of the object-side surface of the fourth lens.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.