High magnification zoom lens barrel including a drive ring having a short length to provide a compact camera
US5801888A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jan 11, 1996 |
| Grant date | Sep 1, 1998 |
| Priority date | — |
| Expiry date | Jan 11, 2016 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG02B7/102
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
A high magnification zoom lens barrel including a drive ring having a short length in the optical axis direction to permit a compact camera configuration. The zoom lens barrel includes a first lens group support member to support a first lens group, and a second lens group support member to support a second lens group. The drive ring advances and withdraws the first lens group support member in the optical axis direction as the drive ring itself advances or withdraws in the optical axis direction as it rotates. The drive ring drives the first lens group support member with helicoids. A drive cam member is driven by the drive ring to rotate so that as the drive cam member rotates, it advances and withdraws the second lens group support member relative to the first lens group support member. A second drive ring is inserted into the drive cam member and rotates relative to the drive ring and is able to move in unison with the drive ring in the optical axis direction.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.