Variable focal length camera with focus adjusting device
US5086312A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Aug 31, 1990 |
| Grant date | Feb 4, 1992 |
| Priority date | — |
| Expiry date | Aug 31, 2010 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG02B7/10
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
A variable focal length camera having at least one auxiliary lens system which is inserted into or withdrawn from the optical axis of a main lens system. A lens holder holding the auxiliary lens system is swingably mounted on a shaft extending in the direction of the optical axis, and moves forward and rearward along the shaft for focus adjustment. In order to cancel the component of a force in the direction of the optical axis exerted by a tool by which a focus adjusting device is operated, the shaft is arranged to be motionless in the direction of the optical axis. According to a preferred embodiment, on the intermediate portion of the shaft, there is formed a thread meshing with a base portion of the lens holder so that the position of the lens holder is adjusted through rotation of the shaft, and after this lens position adjustment the base portion is fixed to the shaft.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.