Lens control apparatus
US6118945A · kind A · utility
10Cited by
6References
20Claims
0Family size
Assignee
Inventor
Key dates
| Filing date | Mar 15, 1999 |
| Grant date | Sep 12, 2000 |
| Priority date | — |
| Expiry date | Mar 15, 2019 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG05B2219/45184
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A lens control apparatus drives a lens with a sine wave by means of a pulse motor and detects the position of the lens by counting the number of pulses during the driving of the pulse motor, and stores a stop phase which is reached by a rotor when the pulse motor is brought to a driving-stopped state. When the lens control apparatus is to move the lens to an initial position and initialize a counter for detecting the position of the lens, the lens control apparatus corrects the count value of the counter by using information indicative of the stored stop phase of the rotor.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.