Back to results
US 6,639,744 B2Granted
Objective lens actuating device
AssigneeRicoh Company, Ltd.
InventorTakehide Ohno
Life of this patent
Estimating the term…
Abstract
In an objective lens actuating device, a magnetic field generating part generates a magnetic field with a focusing coil in a gap formed by an inner yoke and an outer yoke and an auxiliary magnetic field generating part generates an opposite magnetic field in respect to the magnetic field which is generated in the gap towards the focusing coil, at both ends of the inner yoke vertical to the focusing direction.
Claims24
An objective lens actuating device comprising:
- a holder holding an objective lens in a focusing direction;
- a focusing coil cylindrically wound in an axis parallel with an optical axis of said objective lens and fixed on the holder;
- an inner yoke located inside said focusing coil;
- an outer yoke arranged to partially sandwich said focusing coil and face said inner yoke;
- a magnetic field generating part generating a magnetic field with said focusing coil in a gap formed by said inner and outer yokes;
- and
- an auxiliary magnetic field generating part generating an opposite magnetic field in respect to said magnetic field generated in the gap towards said focusing coil, at both ends of said inner yoke vertical to said focusing direction.
4 more elements
An objective lens actuating device comprising:
- an objective lens adapted to being held in a focusing direction;
- a focusing coil cylindrically wound in an axis parallel with an optical axis of said objective lens;
- an inner yoke located inside said focusing coil;
- an outer yoke partially sandwiching said focusing coil and facing said inner yoke;
- a magnetic field generating part adapted to generate a first magnetic field with said focusing coil in a gap formed by said inner and outer yokes;
- and
- an auxiliary magnetic field generating part adapted to generate a second magnetic field opposite said first magnetic field at both ends of said inner yoke vertical to said focusing direction.
4 more elements
An objective lens actuating device comprising:
- a holder holding an objective lens in a focusing direction and in a tracking direction;
- a focusing coil cylindrically wound in an axis parallel with an optical axis of said objective lens and fixed on the holder;
- an inner yoke located inside said focusing coil;
- an outer yoke arranged to partially sandwich said focusing coil and face said inner yoke;
- a magnetic field generating part generating a magnetic field with said focusing coil in a gap formed by said inner and outer yokes;
- and
- an auxiliary magnetic field generating part generating an opposite magnetic field in respect to said magnetic field generated in the gap towards said focusing coil, at both ends of said inner yoke vertical to said focusing direction.
4 more elements
An objective lens actuating device comprising:
- an objective lens adapted to being held in a focusing direction and a tracking direction;
- a focusing coil cylindrically wound in an axis parallel with an optical axis of said objective lens;
- an inner yoke located inside said focusing coil;
- an outer yoke partially sandwiching said focusing coil and facing said inner yoke;
- a magnetic field generating part adapted to generate a first magnetic field with said focusing coil in a gap formed by said inner and outer yokes;
- and
- an auxiliary magnetic field generating part adapted to generate a second magnetic field opposite said first magnetic field at both ends of said inner yoke vertical to said focusing direction.
4 more elements
Dependencies are inferred from the claim text.