Digital camera module having linear voice coil actuator

• US 7,701,507 B2
• Filed: 06/23/2006
• Issued: 04/20/2010
• Est. Priority Date: 10/28/2005
• Status: Expired due to Fees

• Current Assignee: Hon Hai Precision Industry Co., Ltd.
• Original Assignee: Hon Hai Precision Industry Co., Ltd.
• Inventors: Chen, Ga-Lane
• Primary Examiner(s): Chan; Jason
• Assistant Examiner(s): KHAN, USMAN A
• Application Number:
  US11/474,171
• Publication Number:
  US 20070097218A1
• Time in Patent Office: 1,397 Days
• Field of Search: 348/218.1, 348/208.2, 348/208.4, 348/294, 348/373, 348/374, 381/396
• US Class Current: 348/374
• CPC Class Codes: H04N 23/54 Mounting of pick-up tubes, electronic image sensors, deviation or focusing coils
• CPC Class Codes: H04N 23/57 Mechanical or electrical details of cameras or camera modules specially adapted for being embedded in other devices

Abstract

A digital camera module (100) includes a lens module (110), an image sensor (120) and a linear voice coil actuator (130). The lens module further includes a lens set (111), an infrared cut filter (112), a spacer set (113) and a barrel (114). The image sensor is a CCD or a CMOS. The linear voice coil actuator includes an elongated soft magnetic core (131), a tubular permanent magnet (132) positioned parallel to the axis of the core, a sliding holder (133) and a coil (134) attached to the sliding holder and positioned to interact with the permanent magnet along the axis of the core. The digital camera module further includes a servo-controller (140) for controlling the movement of the linear voice coil actuator.

Claims

1. A digital camera module comprising:

a lens module configured for transmitting an image;

an image sensor configured for receiving the image transmitted from the lens module and converting the image from a light signal form into an electronic signal form; and

a linear voice coil actuator configured for driving the image sensor to move so as to properly receive the image transmitted from the lens module;

wherein the linear voice coil actuator comprises;

an elongated soft magnetic core;

a tubular permanent magnet receiving the elongated soft magnetic core therein;

a coil surrounding and moveable relative to the elongated soft magnetic core; and

a sliding holder having;

a fixing portion received in the tubular permanent magnet and fixedly coupled to the coil,

a driving portion on which the image sensor is attached, the driving portion being configured for driving the image sensor to move, and

a connecting portion interconnecting the fixing portion with the driving portion.

2. The digital camera module as claimed in claim 1, wherein the lens module comprises a lens set, an infrared cut filter, a spacer set, and a barrel receiving the lens set and the infrared cut filter therein.

3. The digital camera module as claimed in claim 2, wherein the lens set comprises at least a glass aspheric lens and at least a plastic aspheric lens.

4. The digital camera module as claimed in claim 3, wherein at least one of the at least a glass aspheric lens and the at least a plastic aspheric lens has an anti-reflective film formed on at least one surface thereof.

5. The digital camera module as claimed in claim 1, wherein the image sensor is a CCD.

6. The digital camera module as claimed in claim 1, wherein the image sensor is a CMOS.

7. The digital camera module as claimed in claim 1, wherein the tubular permanent magnet has a slit configured for allowing the connecting portion to extend therethrough and to be slidable therein.

8. The digital camera module as claimed in claim 1, further comprising a servo-controller for controlling movement of the coil of the linear voice coil actuator.

9. The digital camera module as claimed in claim 1, wherein the image sensor is arranged in the tubular permanent magnet.

10. The digital camera module as claimed in claim 1, wherein the image sensor is arranged outside the tubular permanent magnet.

11. The digital camera module as claimed in claim 1, wherein a step resolution of the linear voice coil actuator is in a range of 0.01 micrometers to 0.02 micrometers.

12. The digital camera module as claimed in claim 10, wherein the permanent magnet has a slit configured for allowing the connecting portion to extend therethrough.

13. A digital camera module comprising:

a lens module configured for transmitting an image;

an image sensor configured for receiving the image transmitted from the lens module and converting the image from a light signal form into an electronic signal form; and

a linear voice coil actuator comprising;

a permanent magnet defining a cavity therein;

an elongated soft magnetic core received in the cavity, the soft magnetic core defining an axis;

a coil surrounding the soft magnetic core, the coil being received in the cavity and positioned to interact with the permanent magnet along the axis of the soft magnetic core; and

a sliding holder fixedly coupled to the coil, the image sensor being attached on the sliding holder, the sliding holder capable of moving along the axis of the soft magnetic core by a magneto-motive force thereby driving the image sensor closer to or further away from the lens module.

14. The digital camera module as claimed in claim 13, wherein the sliding holder comprises a fixing portion, a driving portion and a connecting portion interconnecting the fixing portion and the driving portion, the fixing portion is received in the cavity and fixedly coupled to the coil, and the image sensor is attached on the driving portion.

15. The digital camera module as claimed in claim 14, wherein the driving portion and the image sensor are arranged outside the permanent magnet, and the permanent magnet has a slit through which the connecting portion extends.

16. The digital camera module as claimed in claim 13, wherein the coil is attached to the sliding holder, and the image sensor is arranged in the permanent magnet.

17. The digital camera module as claimed in claim 13, wherein the lens module comprises a lens set, an infrared cut filter, a spacer set, and a barrel receiving the lens set and the infrared cut filter therein.

18. A digital camera module comprising:

a lens module configured for transmitting an image;

an image sensor configured for receiving the image transmitted from the lens module and converting the image from a light signal form into an electronic signal form; and

a linear voice coil actuator comprising;

a permanent magnet defining a cavity therein;

an elongated soft magnetic core set received in the cavity, the soft magnetic core set defining an axis;

a coil surrounding the soft magnetic core set, the coil being received in the cavity and positioned to interact with the permanent magnet along the axis of the soft magnetic core set; and

a sliding holder fixedly coupled to the coil, the image sensor being attached on the sliding holder, the sliding holder capable of moving along the axis of the soft magnetic core set by a magneto-motive force thereby driving the image sensor closer to or further away from the lens module.

19. The digital camera module as claimed in claim 18, wherein the coil is attached to the sliding holder, and the image sensor is arranged in the permanent magnet.

20. The digital camera module as claimed in claim 19, wherein the soft magnetic core set comprises a plurality of separating plates.