Voice coil motor optical image stabilization
Some embodiments provide an apparatus for controlling the motion of a camera component. In some embodiments, the apparatus includes an actuator module. The actuator module includes a plurality of magnets. Each magnet of the plurality of magnets is poled with magnetic domains substantially aligned in the same direction throughout each magnet. The apparatus further includes a coil rigidly disposed around a lens. Each magnet of the plurality of magnets contributes to the forces to adjust focus of the lens based on Lorentz forces generated from the coil.
1. A device, comprising:
a lens;
an image sensor; and
an actuator module, comprising:
a plurality of actuators positioned around a periphery of the actuator module and each comprising a coil and a magnet, wherein respective actuators of the plurality of actuators are configured to be driven independently with respective coils receiving separate electrical currents different from each other and through different respective terminals to control tilt positioning of the lens relative to the image sensor, wherein the coils of the plurality of actuators are attached to a moving component of the actuator module for tilting the lens relative to the image sensor.
2. The device of claim 1 , wherein the plurality of actuators comprises four actuators, wherein a first and a fourth ones of the actuators are positioned in two corners of the actuator module opposite each other with respect to a first axis orthogonal to an optical axis of the lens, and wherein a second and a third ones of the actuators are positioned in two corners of the actuator module opposite each other with respect to a second axis orthogonal to the optical axis of the lens.
3. The device of claim 2 , wherein the first and the fourth actuators are configured to be driven with electrical currents of a same polarity to move the lens relative to the image sensor along the optical axis of the lens.
4. The device of claim 2 , wherein the first and the fourth actuators are configured to be driven with electrical currents of different polarities to tilt the lens relative to the image sensor about the first axis orthogonal to the optical axis of the lens.
5. The device of claim 2 , wherein the second and the third actuators are configured to be driven with respective currents to move the lens relative to the image sensor along the optical axis of the lens or tilt the lens relative to the image sensor about the second axis orthogonal to the optical axis of the lens.
6. The device of claim 2 , wherein the coils of adjacent ones of the actuators are wound in opposite ways or are electrically connected in opposite ways.
7. The device of claim 2 , wherein the magnets of the actuators are dual-pole magnets, and wherein the magnets of adjacent ones of the actuators are poled in opposite ways.
8. The device of claim 1 , wherein the coil of each actuator comprises two terminals, wherein one terminal from each actuator is electrically connected with each other, and wherein another terminal from each of the actuators is driven with a current source or a voltage source.
9. The device of claim 8 , wherein one of the other terminals from the actuators is driven with a voltage source, and wherein remaining ones of the other terminals from the actuators are respectively driven with a bidirectional current source.
10. The device of claim 1 , wherein the coils of the actuators are mounted to the lens or a support structure of the lens to move or tilt together with the lens relative to the image sensor, and wherein the magnets of the actuators are mounted to another structure of the device to remain static when the lens moves or tilts.
11. A method, comprising:
determining electrical currents for respective coils of a plurality of actuators of a device for controlling a lens of the device to a position relative to an image sensor of the device, wherein the actuators respectively comprise a coil and a magnet and are positioned around a periphery within a camera, wherein the respective coils of the actuators are able to be driven independently with separate electrical currents different from each other and through different respective terminals to control tilt positioning of the lens relative to the image sensor, and wherein the coils of the plurality of actuators are attached to a moving component for tilting the lens relative to the image sensor; and
providing the determined electrical currents to drive the coils to control the lens to the position relative to the image sensor.
12. The method of claim 11 , wherein the plurality of actuators comprises four actuators, wherein a first and a fourth ones of the actuators are positioned opposite each other with respect to a first axis orthogonal to an optical axis of the lens, and wherein a second and a third ones of the actuators are positioned opposite each other with respect to a second axis orthogonal to the optical axis of the lens.
13. The method of claim 12 , further comprising:
providing at least one pair of electrical currents of a same polarity to the first and fourth actuators, or to the second and third actuators, to move the lens relative to the image sensor along an optical axis of the lens.
14. The method of claim 12 , further comprising:
providing at least one pair of electrical currents of different polarities to the first and the fourth actuators to tilt the lens relative to the image sensor about the first axis orthogonal to the optical axis of the lens, or to the second and third actuators to tilt the lens relative to the image sensor about the second axis orthogonal to the optical axis of the lens.
15. The method of claim 11 , wherein the coil of each actuators comprises two terminals, wherein one terminal from each actuator is electrically connected with each other, and wherein another terminal from each of the actuators is driven with a current source or a voltage source.
16. The method of claim 11 , wherein the magnets of the actuators are dual-pole magnets.
17. The method of claim 11 , wherein the coils of the actuators are mounted to the lens or a support structure of the lens to move or tilt together with the lens relative to the image sensor, and wherein the magnets of the actuators are mounted to another structure of the device to remain static when the lens moves or tilts.
18. A device, comprising:
a lens;
an image sensor configured to generate one or more signals based on light that passes through the lens;
an actuator module, comprising:
a plurality of actuators positioned around a periphery of the actuator module and each comprising a coil and a magnet, wherein respective actuators of the plurality of actuators are configured to be driven independently with respective coils receiving separate electrical currents different from each other and through different respective terminals to control tilt positioning the lens relative to the image sensor, and wherein the coils of the plurality of actuators are attached to a moving component of the actuator module for tilting the lens relative to the image sensor; and
a processor configured to process the signals generated from the image sensor to generate an image.
19. The device of claim 18 , wherein the plurality of actuators comprises four actuators, wherein a first and a fourth ones of the actuators are positioned in two corners of the actuator module opposite each other with respect to a first axis orthogonal to an optical axis of the lens, and wherein a second and a third ones of the actuators are positioned in two corners of the actuator module opposite each other with respect to a second axis orthogonal to the optical axis of the lens.
20. The device of claim 19 , wherein the first and the fourth actuators are configured to be driven with electrical currents of a same polarity to move the lens relative to the image sensor along the optical axis of the lens, or driven with electrical currents of different polarities to tilt the lens relative to the image sensor about the first axis orthogonal to the optical axis of the lens, and wherein the second and the third actuators are configured to be driven with electrical currents of a same polarity to move the lens relative to the image sensor along the optical axis of the lens, or driven with electrical currents of different polarities to tilt the lens relative to the image sensor about the second axis orthogonal to the optical axis of the lens.