Lens control apparatus configured in an imaging device

• US 10,638,032 B2
• Filed: 04/27/2018
• Issued: 04/28/2020
• Est. Priority Date: 04/27/2017
• Status: Active Grant

• Current Assignee: AP Photonics (Shenzhen) Limited
• Original Assignee: AP Photonics (Shenzhen) Limited
• Inventors: Lau, Herbert Chi-Yuen, Hong, Hang Qing
• Primary Examiner(s): Berardesca, Paul M
• Application Number:
  US15/964,199
• Publication Number:
  US 20180316847A1
• Time in Patent Office: 732 Days
• 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 7/09 adapted for automatic focusing or varying magnification
• CPC Class Codes: H04N 23/54 Mounting of pick-up tubes, electronic image sensors, deviation or focusing coils
• 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 23/67 Focus control based on electronic image sensor signals
• CPC Class Codes: H04N 23/68 for stable pick-up of the scene, e.g. compensating for camera body vibrations

Abstract

Embodiments of the present disclosure pertains to a lens control apparatus that can be implemented in an imaging device to provide autofocus (AF) and image stabilization (IS) functionalities. The lens control apparatus includes a casing, a lens carrier movable in said casing and configured to hold an imaging lens, a pair of focusing coils disposed within said casing and configured to enable linear motion of the lens carrier along an optical axis, and a set of actuating coils disposed within said casing and configured to pivot the lens carrier in a first direction relative to the optical axis and a second direction relative to the optical axis, said first direction and said second direction being orthogonal to each other, and wherein the lens control apparatus is capable of providing at least three degrees of freedom to the lens carrier.

Claims

1. A lens control apparatus comprising:

a casing;

a lens carrier movable in said casing and configured to hold an imaging lens;

a pair of focusing coils disposed within said casing and configured to enable linear motion of the lens carrier along an optical axis; and

a set of actuating coils disposed within said casing and configured to pivot the lens carrier in a first direction relative to the optical axis and a second direction relative to the optical axis, said first direction and said second direction being orthogonal to each other, wherein a pivot point is configured on the optical axis to pivot the lens carrier in the first direction and the second direction about the pivot point, and

wherein the lens control apparatus is capable of providing at least three degrees of freedom to the lens carrier;

wherein the set of actuating coils comprise at least two pairs of actuating coils, each actuating coil of a pair of actuating coils mounted on one of diagonally opposite surfaces of the lens carrier;

wherein each pair of actuating coils is mounted on a surface of a focusing coil of the pair of focusing coils, and wherein each focusing coil of the pair of focusing coils are wound concentrically around the lens carrier.

2. The lens control apparatus of claim 1, further comprising a pair of magnetic elements having opposite polarities, each magnetic element disposed within the casing on either side of the lens carrier.

3. The lens control apparatus of claim 1, wherein actuating coils of the pair of actuating coils are electrically coupled with each other and have reverse coil windings with respect to each other.

4. The lens control apparatus of claim 1, wherein focusing coils of the pair of focusing coils are electrically coupled with each other and have reverse coil windings with respect to each other.

5. The lens control apparatus of claim 1, further comprising a pair of springs, each spring of the pair of springs positioned on either side of the lens carrier and adapted to firmly hold the lens carrier within the casing.

6. The lens control apparatus of claim 5, wherein at least one spring of the pair of springs comprises a plurality of independent spring elements to drive electrical current in any or a combination of the set of actuating coils and the pair of focusing coils.

7. The lens control apparatus of claim 5, configuration of the pivot point on the optical axis is based on ratio of spring constant between each spring of the pair of springs.

8. The lens control apparatus of claim 1, wherein said apparatus is adapted to provide imagery using the imaging lens on a surface of a spherical shaped curved photo-sensor, spherical shape of the curved photo-sensor being symmetrical about the optical axis.

9. The lens control apparatus of claim 8, wherein the pivot point is configured to coincide with radius of curvature of the curved photo-sensor.

10. The lens control apparatus of claim 1, wherein movement of the lens carrier is controlled using a control unit.

11. The lens control apparatus of claim 10, wherein the control unit is operatively coupled with at least one motion sensor.

12. The lens control apparatus of claim 10, wherein the control unit is operatively coupled with at least one position feedback sensor.

13. An imaging device comprising a lens control apparatus, wherein said lens control apparatus comprises:

a casing;

a lens carrier movable in said casing and configured to hold an imaging lens;

a pair of focusing coils disposed within said casing and configured to enable linear motion of the lens carrier along an optical axis; and

a set of actuating coils disposed within said casing and configured to pivot the lens carrier in a first direction relative to the optical axis and a second direction relative to the optical axis, said first direction and said second direction being orthogonal to each other, wherein a pivot point is configured on the optical axis to pivot the lens carrier in the first direction and the second direction about the pivot point, and

wherein the lens control apparatus is capable of providing at least three degrees of freedom to the lens carrier;

wherein the set of actuating coils comprise at least two pairs of actuating coils, each actuating coil of a pair of actuating coils mounted on one of diagonally opposite surfaces of the lens carrier;

wherein each pair of actuating coils is mounted on a surface of a focusing coil of the pair of focusing coils, and wherein each focusing coil of the pair of focusing coils are wound concentrically around the lens carrier.

14. The imaging device of claim 13, further comprising a curved photo-sensor having spherical shape symmetrical about the optical axis.

15. The imaging device of claim 13, further comprising a control unit configured to control movement of the lens carrier.

16. The imaging device of claim 13, wherein the control unit is operatively coupled with at least one motion sensor.

17. The imaging device of claim 13, wherein the lens control apparatus further comprises a pair of springs, each spring of the pair of springs positioned on either side of the lens carrier and adapted to firmly hold the lens carrier within the casing.

18. The imaging device of claim 17, wherein configuration of the pivot point on the optical axis is based on ratio of spring constant between each spring of the pair of springs.