Optical image stabilization mechanism
An optical image stabilization mechanism is provided, including a holder for holding a lens, a frame, a base, a first coil, a second coil, a displacement sensor, a first magnetic element, a second magnetic element, and a third magnetic element. The frame is movably connected to the holder and the base. The first coil is disposed on a side of the holder. The second coil is disposed on the base. The first and second magnetic elements are disposed on the frame and correspond to the first coil. The magnetic pole direction of the first magnetic element is opposite to that of the second magnetic element. The third magnetic element is disposed on the frame and corresponds to the second coil. The displacement sensor is disposed on the base to detect relative displacement between the lens and the base.
1. An optical image stabilization mechanism, comprising:
only one holder, configured to holding a lens having an optical axis, wherein the holder has:
a first side surface;
a second side surface, parallel to the first side surface, and the lens disposed between the first side surface and the second surface;
a third side surface, not parallel to the first side surface and the second side surface; and
a fourth side surface, parallel to the third side surface, and the lens is disposed between the third side surface and the fourth side surface;
a frame, movably connected to the holder;
a base, movably connected to the frame;
wherein the base has a non-square rectangular structure viewed along the optical axis, and includes:
a first side; and
a second side, wherein viewed along the optical axis, a length of the first side is less than a length of the second side,
wherein viewed along the optical axis, the first side surface is located on the first side, and the third side surface is located on the second side;
a first coil, affixed to the first side surface;
a plurality of second coils, affixed to the base;
wherein at least one of the second coils is located on the first side viewed in the optical axis;
a first magnetic element, affixed to the frame and corresponding to the first side surface, and the first magnetic element is corresponding to the first coil;
a second magnetic element, affixed to the frame and corresponding to the first side surface, and the first magnetic element is corresponding to the first and second coils, wherein the first and the second magnetic elements are arranged along a direction parallel to the optical axis, and magnetic poles of the first and second magnetic elements are opposite to each other; and
a third magnetic element, affixed to the frame and corresponding to the third side surface, and the third magnetic element is corresponding to the second coils, wherein the first coil is not disposed on the third side surface.
2. The optical image stabilization mechanism as claimed in claim 1 , further comprising a multi-polar magnet including the first and second magnetic elements integrally formed in one piece, wherein both the first and second magnetic elements have a pair of magnetic poles, wherein each pair of magnetic poles has N pole and S pole.
3. The optical image stabilization mechanism as claimed in claim 1 , wherein the optical image stabilization mechanism has a rectangular structure viewed from the optical axis.
4. The optical image stabilization mechanism as claimed in claim 1 , wherein the first side surface has a protrusion, and the first coil surrounds the protrusion.
5. The optical image stabilization mechanism as claimed in claim 4 , wherein the protrusion has a recess.
6. The optical image stabilization mechanism as claimed in claim 4 , wherein the first coil overlaps the protrusion of the holder viewed from the optical axis.
7. The optical image stabilization mechanism as claimed in claim 1 , further comprising:
a plurality of first coils, respectively affixed to the first and second side surfaces;
a plurality of first magnetic elements, respectively corresponding to the first coils; and
a plurality of second magnetic elements, respectively corresponding to the first coils.
8. The optical image stabilization mechanism as claimed in claim 7 , wherein no coil is disposed on the third and fourth side surfaces.
9. The optical image stabilization mechanism as claimed in claim 1 , wherein a shortest distance between the first magnetic element and the optical axis is greater than a shortest distance between the third magnetic element and the optical axis.
10. The optical image stabilization mechanism as claimed in claim 1 , wherein a distance between a center of the holder and the base is greater than a distance between a center of the first coil and the base.
11. The optical image stabilization mechanism as claimed in claim 1 , further comprising:
an elastic element, elastically connecting the frame and the holder, and a holder-fixing portion of the elastic element is affixed to the holder, wherein the holder-fixing portion is partially overlapped with the first coil viewed in a direction perpendicular to the optical axis.