Zoom lens device with zooming position detector
US6195211A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Mar 28, 2000 |
| Grant date | Feb 27, 2001 |
| Priority date | — |
| Expiry date | Mar 28, 2020 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG02B15/142
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
A zoom lens device has a zooming position detector consisting of a code plate and a brush device. The code plate is mounted to a front face of a shutter unit that is attached to a front end of an axial movement barrel. The axial movement barrel is located inside a helical movement barrel so as to be immovable in the axial direction relative to the helical movement barrel, but is rotated relative to the helical movement barrel for zooming. The brush device is mounted to an inner peripheral portion of a lens barrel that is located near the face of the shutter unit and rotates relative to the face of the shutter unit, such that the electric contact strips brush the code plate while the shutter unit rotates relative to the lens barrel for zooming. A zooming position of the zoom lens device is determined based on output signals from the brush device.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.