LENS DRIVING DEVICE AND CAMERA

• US 20160025995A1
• Filed: 02/14/2013
• Published: 01/28/2016
• Est. Priority Date: 02/14/2012
• Status: Active Grant

• Current Assignee: Mitsumi Electric Co., Ltd. (MinebeaMitsumi Inc.)
• Original Assignee: Mitsumi Electric Co., Ltd. (MinebeaMitsumi Inc.)
• Inventors: ARIJI, Makoto
• Granted Patent: US 9,933,628 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: G02B 13/001 Miniaturised objectives for electronic devices, e.g. portable telephones, webcams, PDAs, small digital cameras G02B23/243 takes precedence
• CPC Class Codes: G02B 27/646 compensating for small deviations, e.g. due to vibration or shake movement of one or more optical elements for control of motion blur in cameras, projectors or printers G03B2205/0007; image stabilisation in cameras peculiar to the presence or use of an electronic image sensor H04N23/68
• CPC Class Codes: G02B 7/023 permitting adjustment
• CPC Class Codes: G02B 7/08 adapted to co-operate with a remote control mechanism
• CPC Class Codes: G02B 7/09 adapted for automatic focusing or varying magnification
• CPC Class Codes: G03B 2205/0007 Movement of one or more optical elements for control of motion blur imaging systems in general using optical elements for stabilisation of the position of the image G02B27/64
• CPC Class Codes: G03B 2205/0069 using electromagnetic actuators, e.g. voice coils
• CPC Class Codes: G03B 3/10 Power-operated focusing
• CPC Class Codes: G03B 3/12 adapted for remote control
• CPC Class Codes: G03B 5/02 Lateral adjustment of lens
• CPC Class Codes: G03B 5/04 Vertical adjustment of lens; Rising fronts
• CPC Class Codes: H04N 23/57 Mechanical or electrical details of cameras or camera modules specially adapted for being embedded in other devices
• CPC Class Codes: H04N 23/687 by shifting the lens or sensor position

Abstract

A lens driving device includes: a lens holder; a first coil wound onto the lens holder around the optical axis direction; a plurality of magnets having a first surface and a second surface perpendicular to the first surface, the magnets being disposed in a state in which the first surface opposes a circumferential surface of the first coil; a magnet holder that fixes the magnets apart from each other; a yoke constituting, together with the magnets, a magnetic circuit having a magnetic flux that traverses the first coil; a second coil provided opposite the second surface of the magnets; and a base on which the second coil is disposed. An auto-focus lens driving part that includes the lens holder, the first coil, the magnets, the magnet holder, and the yoke is held on the base so as to allow relative displacement in a direction perpendicular to the optical axis.

Claims

1. A lens driving device, comprising:

a lens holder to which a lens barrel is mountable, the lens holder being movable in a direction of an optical axis;

a first coil wound around the lens holder about the optical axis;

a plurality of magnets that have a first surface magnetized to a south pole or a north pole and a second surface that is perpendicular to the first surface and the optical axis, the magnets being disposed in a state in which the first surface faces a circumferential face of the first coil;

a magnet holder that fixes the plurality of magnets apart from each other;

a yoke constituting, together with the plurality of magnets, a magnetic circuit that generates a magnetic flux that crosses the first coil;

a second coil that is provided facing the second surface of the magnets; and

a base on which the second coil is disposed;

wherein an auto-focusing lens driving portion that includes the lens holder, the first coil, the plurality of magnets, the magnet holder and the yoke is held so as to be relatively movable in a direction perpendicular to the optical axis with respect to the base.

2. The lens driving device according to claim 1, wherein the magnet holder is a polyangular frame body.

3. The lens driving device according to claim 2, wherein the plurality of magnets are fixed to the magnet holder at positions such that adjacent magnets are in a perpendicular relationship with respect to each other.

4. The lens driving device according to claim 3, wherein the number of the magnets is four.

5. The lens driving device according to claim 1, wherein the yoke comprises a first yoke portion that is disposed facing the first surface of the plurality of magnets with the first coil sandwiched therebetween, and a second yoke portion that is disposed facing a third surface opposite to the second surface of the magnets.

6. The lens driving device according to claim 5, wherein a plurality of the first yoke portions have a wall surface that faces separation parts between adjacent magnets and the first surface of the respective magnets, and are coupled by means of the second yoke portion.

7. The lens driving device according to claim 6, wherein the number of the first yoke portions is four.

8. The lens driving device according to claim 1, wherein the yoke is fixed to the magnet holder.

9. The lens driving device according to claim 1, wherein:

the yoke comprises a plurality of members; and

a predetermined part of the lens holder is located between the plurality of members.

10. The lens driving device according to claim 1, wherein the second coil comprises a plurality of coil parts.

11. The lens driving device according to claim 10, wherein a position detection arrangement is disposed at a place where the plurality of coil parts are separated.

12. The lens driving device according to claim 1, wherein an image pickup device is mountable on the base.

13. A camera comprising the lens driving device according to claim 1 incorporated therein.