Zooming control apparatus for a camera
US5148201A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | May 23, 1991 |
| Grant date | Sep 15, 1992 |
| Priority date | — |
| Expiry date | May 23, 2011 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG02B7/102
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
A zoom lens is zoomed selectively in either of two opposite directions by a motor which is rotated by a driver. First and second zoom switches cause the zoom lens to move at a higher speed. Third and fourth zoom switches cause the zoom lens to move at a lower speed for precisely stopping the zoom lens. A CPU connected to the four switches controls a zoom motor to rotate selectively at higher and lower speeds. The first and third zoom switches cause the zoom lens to move in the direction of telephotography, while the second and fourth zoom switches cause the zoom lens to move in the direction of wide-angle photography. In order to keep the speed of the zoom lens unchanged despite the difference in its direction, an electric current of a larger electric power is applied to the motor for rotation in the direction that requires more work.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.