Zoom lens barrel for macrofocusing
US4523815A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Jul 1, 1983 |
| Grant date | Jun 18, 1985 |
| Priority date | — |
| Expiry date | Jul 1, 2003 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG02B7/10
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
A zoom lens barrel capable of macro-photographing, having lens assemblies with a focusing lens assembly has a mount ring, a zooming ring and a focusing ring. The barrel further comprises a guide means between the mount ring and the focusing ring for enabling the focusing ring not only to rotate for normal photographing, and for macro-photographing, but also to move in the axial direction, a connecting ring which rotates to move only the focusing lens assembly, a macrohelicoid ring which rotates to move the whole lens assemblies while maintaining a predetermined spatial relationship therebetween, and a switching means for selectively connecting the connecting ring or the macrohelicoid ring to the focusing ring in accordance with the axial movement of the focusing ring.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.