Lens barrel of short length having the capability of a large zooming magnification and a zoom lens capable of a large forward movement
US5373397A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jan 8, 1993 |
| Grant date | Dec 13, 1994 |
| Priority date | — |
| Expiry date | Jan 8, 2013 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG02B7/102
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
A lens barrel having a fixed frame fixed to the body of a camera; a first cam frame mounted to rotate about the outer surface of the fixed frame; a second cam frame arranged inside the fixed frame and rotatable around the optical axis upon rotation of the first cam frame; a movable member integral with the second cam frame, extending in the direction of the optical axis and rotatable around the optical axis so that rotation of the movable member around the optical axis with respect to the fixed frame is restricted, the movable member having a linear-movement key extending in the direction of the optical axis; a lens holding frame inside the second cam frame and guided by with the movable member around the optical axis, the movable member being connected to the second cam frame on the outer surface thereof, the lens holding frame engaging the inner surface of the linear-movement key, and movable forward/rearward along the optical axis due to rotation of the second cam frame; and another lens holding frame movable forward/rearward along the optical axis due to rotation of the second cam frame, and limited to linear movement by the linear movement key.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.