Photographic lens for electronic still camera
US5963381A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Dec 23, 1997 |
| Grant date | Oct 5, 1999 |
| Priority date | — |
| Expiry date | Dec 23, 2017 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG02B13/04
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
Successively from an object side, a negative lens having a concave surface directed onto an image surface side, a positive meniscus lens having a convex surface directed onto the image surface side, a positive lens having a convex surface directed onto the image surface side, a negative lens having a concave surface directed onto the image surface side, and a biconvex lens are disposed, thereby yielding a photographic lens for electronic still camera which can favorably correct distortion while attaining a compact size and a wide angle of view. Successively disposed from the object side are a negative first lens L.sub.1 having a concave surface directed onto the image surface side, a second lens L.sub.2 made of a positive meniscus lens having a convex surface directed onto the image surface side, a third lens L.sub.3 made of a biconvex lens whose surface with a stronger curvature is directed onto the image surface side, a negative fourth lens L.sub.4 having a concave surface directed onto the image surface side, and a fifth lens L.sub.5 made of a biconvex lens; while being configured to satisfy the following conditional expressions (1) to (4): EQU 0.8<-f.sub.1 /f<1.2 (1) EQU 1.1<f.…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.