Zoom lens barrel with decreased outer diameter
US5892988A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Jan 30, 1997 |
| Grant date | Apr 6, 1999 |
| Priority date | — |
| Expiry date | Jan 30, 2017 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG02B7/10
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
Because the keys located on the first rotating barrel have essentially the same inner diameter as the second rotating barrel, no unnecessary space is formed inside the first rotating barrel and the second rotating barrel. In addition, although the inner diameter of the keys of the first rotating barrel and the inner diameter of the second rotating barrel are essentially the same, because the keys engage with the straight advancement grooves on the second rotating barrel, the first rotating barrel and the second rotating barrel do not interfere with each other. Moreover, because the keys that are thinner than the second rotating barrel overlap with the second rotating barrel, said the keys being inside the second rotating barrel, the thickness of the keys does not affect the outer diameter of the lens barrel at all. Therefore, it is only the first straight advancing barrel that is located outside the second rotating barrel to move out the second rotating barrel and that adds to the outer diameter of the lens barrel.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.