Lens drive device, camera module, and camera-mounting device

• US 10,281,691 B2
• Filed: 12/24/2015
• Issued: 05/07/2019
• Est. Priority Date: 12/25/2014
• Status: Active Grant

• Current Assignee: Mitsumi Electric Co., Ltd. (MinebeaMitsumi Inc.)
• Original Assignee: Mitsumi Electric Co., Ltd. (MinebeaMitsumi Inc.)
• Inventors: Sugawara, Masayoshi
• Primary Examiner(s): Alexander, William R
• Assistant Examiner(s): Parbadia, Balram T
• Application Number:
  US15/539,358
• Publication Number:
  US 20180246296A1
• Time in Patent Office: 1,230 Days
• CPC Class Codes: G02B 13/005 having spherical lenses only
• 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 7/04 with mechanism for focusing or varying magnification
• CPC Class Codes: G02B 7/09 adapted for automatic focusing or varying magnification
• CPC Class Codes: G03B 13/36 Autofocus systems
• CPC Class Codes: G03B 2205/0023 by tilting or inclining one or more optical elements with respect to the optical axis
• CPC Class Codes: G03B 2205/0069 using electromagnetic actuators, e.g. voice coils
• CPC Class Codes: G03B 5/00 Adjustment of optical system relative to image or object surface other than for focusing
• CPC Class Codes: G03B 5/06 Swinging lens about normal to the optical axis
• CPC Class Codes: H02K 41/0356 moving along a straight path
• CPC Class Codes: H04N 23/00 Cameras or camera modules comprising electronic image sensors; Control thereof
• CPC Class Codes: H04N 23/55 Optical parts specially adapted for electronic image sensors; Mounting thereof
• 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 23/60 Control of cameras or camera modules

Abstract

A lens drive device is provided with: an AF drive unit that has an AF coil unit and an AF magnet unit and automatically carries out focusing by moving an AF movable unit with respect to an AF fixed unit, making use of drive force from a voice coil motor; and a base unit disposed with an intervening space on the image formation side of the AF drive unit in the direction of the optical axis. The AF drive unit has elastic support units connecting the AF movable unit and the AF fixed unit. The AF movable unit is affixed to the AF fixed unit by being pressed upward to the light receiving side in the direction of the optical axis by the AF magnet unit and urged toward the image formation side in the direction of the optical axis by the elastic support units.

Claims

1. A lens driving device comprising:

an auto-focusing driving part; and

a base part disposed separately from the auto-focusing driving part at a position on an imaging side in a light axis direction,

wherein the auto-focusing driving part includes;

an auto focus movable part including a lens holder and an auto-focusing coil part, the lens holder being configured to hold a lens barrel, the auto-focusing coil part being disposed at the lens holder,

an auto focus fixing part including an auto-focusing magnet part including a magnet holder and an auto-focusing magnet part, the magnet holder having a frame shape, the auto-focusing magnet part being disposed at the magnet holder, wherein the auto focus fixing part is disposed separately from the auto focus movable part outward in a radial direction, and

an elastic supporting part configured to elastically connect the lens holder and the magnet holder, and

wherein the auto-focusing driving part performs automatic focusing by moving the auto focus movable part in the light axis direction with respect to the auto focus fixing part by use of a driving force of a voice coil motor composed of the auto-focusing coil part and the auto-focusing magnet part, and

wherein the auto focus movable part is fixed to the auto focus fixing part in a state where the auto focus movable part is pushed up by the auto-focusing magnet part to a light reception side in the light axis direction, and biased by the elastic supporting part to the imaging side in the light axis direction, the auto focus movable part being pushed up by fixing of the auto-focusing magnet to a predetermined position of the magnet holder in a state where a surface of the auto-focusing magnet part on the light reception side in the light axis direction is in contact with a surface of the lens holder on the imaging side in the light axis direction.

2. The lens driving device according to claim 1 further comprising:

a shake-correcting driving part including a shake-correcting magnet part disposed in the auto-focusing driving part, and a shake-correcting coil part disposed in the base part, the shake-correcting driving part being configured to perform shake correction by swaying, with respect to a shake correction fixing part including the shake-correcting coil part, a shake correction movable part including the shake-correcting magnet part in a plane orthogonal to the light axis direction by use of a driving force of a voice coil motor composed of the shake-correcting coil part and the shake-correcting magnet part.

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

the elastic supporting part includes an upper elastic supporting member configured to elastically connect an upper portion of the lens holder and an upper portion of the magnet holder, and a lower elastic supporting member configured to elastically connect a lower portion of the lens holder and a lower portion of the magnet holder; and

when the auto-focusing magnet part is fixed to a predetermined position of the magnet holder, the lens holder is pushed up to the light reception side in the light axis direction, and biased to the imaging side in the light axis direction by the upper elastic supporting member and the lower elastic supporting member.

4. The lens driving device according to claim 3, wherein:

the lens holder includes at an upper portion thereof a magnet locking part protruding outward in a radial direction over the auto-focusing coil part; and

a surface of the magnet locking part on the imaging side in the light axis direction makes contact with a surface of the auto-focusing magnet part on the light reception side in the light axis direction.

5. A camera module comprising:

the lens driving device according to claim 1;

a lens part mounted to the auto focus movable part; and

an image capturing part configured to capture a subject image imaged with the lens part.

6. A camera mounting device that is an information apparatus or a transport apparatus, the camera mounting device comprising the camera module according to claim 5.