Lens driving apparatus for a camera
US4972215A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Nov 3, 1989 |
| Grant date | Nov 20, 1990 |
| Priority date | — |
| Expiry date | Nov 3, 2009 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG02B7/102
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
A lens driving apparatus for use in a camera, which adjusts the focus or the angle of view of a lens by means of a motor driven in accordance with the amount of rotation and the rotational angle of a rotational operation member provided on a lens body or a camera body, comprises a first detector for detecting the operational direction and the amount of operation of the rotational operation member and generates an operational direction signal and an amount-of-operation pulse signal, a second detector for detecting the actual amount of driving of the lens and generating a drive pulse signal, a motor driver for rotating the motor in a direction according to the operational direction signal until the difference between the count value of an amount-of-operation pulse and an amount-of-driving pulse becomes O, and a velocity controller for setting a high speed to the motor driver when the above difference is large and setting a low speed to the motor drive when the difference is small.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.