Small lens system including seven lenses of ++−+++− or −+−+++− refractive powers
US11409081B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Dec 27, 2019 |
| Grant date | Aug 9, 2022 |
| Priority date | — |
| Expiry date | Apr 21, 2041 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG02B9/64
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
Disclosed is a small lens system including a first lens, a second lens, a third lens, a fourth lens, a fifth lens, a sixth lens, and a seventh lens sequentially arranged from an object, wherein the first lens has a convex surface facing the object, the second lens has a convex surface facing the object and a positive refractive power, the third lens has a positive or negative refractive power, the fourth lens has opposite surfaces convex toward an image, the fifth lens has opposite surfaces convex toward the image, the sixth lens has at least one aspherical surface and is configured such that the object-side surface of the sixth lens is convex in the vicinity of an optical axis, and the seventh lens has at least one aspherical surface and is configured such that at least one inflection point is provided on the aspherical surface of the seventh lens.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.