Optical element driving mechanism

1 . An optical element driving mechanism, comprising:

a fixed portion;

a movable portion, connected to an optical element with an optical axis, movable relative to the fixed portion;

a driving assembly, driving the movable portion to move relative to the fixed portion;

a limiting assembly, disposed on the movable portion and connected with the driving assembly, wherein the driving assembly is limited to move within a movable range relative to the fixed portion by the limiting assembly; and

an adhesive assembly, comprising a first adhesive element, a second adhesive element, a third adhesive element, and a fourth adhesive element,

wherein the limiting assembly comprises a first limiting element and a second limiting element,

wherein when viewed along a first direction parallel to the optical axis, the first limiting element and the second limiting element at least partially overlap,

wherein when viewed along a second direction perpendicular to the first direction, the first limiting element and the second limiting element are symmetrically arranged,

wherein when viewed along a third direction perpendicular to the first direction and the second direction, the first limiting element and the second limiting element do not overlap,

wherein the driving assembly comprises a first driving element and a second driving element, the first driving element and the second driving element have a shape memory alloy, and the first driving element and the second driving element are elongated structures,

wherein two ends of the first driving element are connected to the fixed portion, the first driving element is in contact with the first limiting element and is limited to move by the first limiting element, two ends of the second driving element are connected to the fixed portion, and the second driving element is in contact with the second limiting element and is limited to move by the second limiting element,

wherein when viewed along the second direction, the first driving element and the second driving element do not overlap over the entirety of the lengths of the first driving element and the second driving element;

wherein the first adhesive element is injected from a first side of the first limiting element to fix the first driving element and the first limiting element,

wherein the second adhesive element is injected from a second side of the first limiting element to fix the first driving element and the first limiting element, wherein the first side of the first limiting element and the second side of the first limiting element are opposite to each other,

wherein the third adhesive element is injected from a first side of the second limiting element to fix the second driving element and the second limiting element,

wherein the fourth adhesive element is injected from a second side of the second limiting element to fix the second driving element and the second limiting element, wherein the first side of the second limiting element and the second side of the second limiting element are opposite to each other.

2 . The optical element driving mechanism as claimed in claim 1 , wherein the first limiting element and the second limiting element respectively have a first hook-shaped structure and a second hook-shaped structure,

wherein the first hook-shaped structure extends along the second direction and away from the optical axis, and then extends along the first direction and away from a light incident surface,

wherein the second hook-shaped structure extends along the second direction and away from the optical axis, and then extends along the first direction and close to the light incident surface,

wherein the first hook-shaped structure and the second hook-shaped structure are faced to each other.

3 . The optical element driving mechanism as claimed in claim 2 , wherein the first hook-shaped structure has a first inner surface, the second hook-shaped structure has a second inner surface, and the first inner surface and the second inner surface are faced to each other,

wherein the driving element is in contact with the first inner surface at at least one contact point, and the driving element is in contact with the second inner surface at at least one contact point,

wherein when the first hook-shaped structure is cut with a first imaginary plane and observed, a first contour of the first inner surface is an arc shape protruding toward the second inner surface, and a curvature at the contact point is smaller than a curvature at any one of two side endpoints,

wherein when the second hook-shaped structure is cut with the first imaginary plane and observed, a first contour of the second inner surface is an arc shape protruding toward the first inner surface, and a curvature at the contact point is smaller than a curvature at any one of two side endpoints,

wherein the first imaginary plane is perpendicular to the second direction and passes through the contact point of the first inner surface and the contact point of the second inner surface.

4 . The optical element driving mechanism as claimed in claim 3 , wherein a part of the first inner surface is a first contact surface, and the first contact surface is a plane,

wherein a part of the second inner surface is a second contact surface, and the second contact surface is a plane,

wherein the driving assembly is in contact with the first contact surface, and the driving assembly is in contact with the second contact surface.

5 . The optical element driving mechanism as claimed in claim 3 , wherein when the first hook-shaped structure is cut with a second imaginary plane and observed, a second contour of the first inner surface is an arc shape that is concave away from the second inner surface, and a curvature at the contact point is greater than or equal to a curvature at an outer endpoint,

wherein when the second hook-shaped structure is cut with the second imaginary plane and observed, a second contour of the second inner surface is an arc shape that is concave away from the first inner surface, and a curvature at the contact point is greater than or is equal to a curvature at an outer endpoint,

wherein the second imaginary plane is perpendicular to the third direction and passes through the contact point of the first inner surface and the contact point of the second inner surface.

6 . The optical element driving mechanism as claimed in claim 1 , further comprising a circuit assembly, disposed on a first side of the fixed portion, comprising a first circuit element, a second circuit element, and a third circuit element,

wherein when viewed along the first direction:

the first circuit element and the second circuit element at least partially overlap;

the first circuit element and the third circuit element do not overlap;

the second circuit element and the third circuit element do not overlap,

wherein when viewed along the second direction, the first circuit element, the second circuit element, and the third circuit element do not overlap,

wherein when viewed along the third direction, the first circuit element, the second circuit element, and the third circuit element at least partially overlap.

7 . The optical element driving mechanism as claimed in claim 6 , wherein the first circuit element has a first end portion, the second circuit element has a second end portion, and the third circuit element has a third end portion,

wherein when viewed along the third direction, the first end portion, the second end portion, and the third end portion at least partially overlap

wherein the first end portion, the second end portion, and the third end portion are connected to a driving circuit assembly.

8 . The optical element driving mechanism as claimed in claim 7 , wherein the first circuit element further has an outer curved portion, the second circuit element further has an outer curved portion, and the third circuit element further has a first outer curved portion and a second outer curved portion,

wherein the outer curved portion of the first circuit element, the outer curved portion of the second circuit element, and the first outer curved portion and the second outer curved portion of the third circuit element are all curved outward away from the optical axis,

wherein when viewed along the second direction, the outer curved portion of the first circuit element and the first outer curved portion of the third circuit element are symmetrically disposed, and the outer curved portion of the second circuit element and the second outer curved portion of the third circuit element are symmetrically disposed.

9 . The optical element driving mechanism of claim 8 , wherein when viewed along the third direction, the outer curved portion of the second circuit element is further away from the optical axis than the outer curved portion of the first circuit element, and the second outer curved portion of the third circuit element is further away from the optical axis than the first outer curved portion of the third circuit element.

10 . The optical element driving mechanism as claimed in claim 9 , wherein when viewed along the third direction, the outer curved portion of the second circuit element does not overlap the first end portion and the second end portion, and the second outer curved portion of the third circuit element does not overlap the third end portion.

11 . The optical element driving mechanism as claimed in claim 8 ,

wherein when viewed along the first direction, the first driving element and the second driving element at least partially overlap,

wherein when viewed along the third direction, the first driving element and the second driving element do not overlap,

wherein one end of the first driving element is connected to the outer curved portion of the first circuit element, and the other end is connected to the first outer curved portion of the third circuit element through the first limiting element,

wherein one end of the second driving element is connected to the second circuit element, and the other end is connected to the second outer curved portion of the third circuit element through the second limiting element.

12 . The optical element driving mechanism as claimed in claim 7 , wherein the driving circuit assembly is disposed on the fixed portion, comprising a first input circuit element, a second input circuit element, and an output circuit element,

wherein the first input circuit element has a first connection portion, a first extension portion, and a first external connection portion, the first extension portion is connected to the first connection portion and the first external connection portion, wherein the first connection portion is connected to the first end portion, the first external connection portion protrudes from a second side of the fixed portion and is connected to an external driving power source, wherein the second side and the first side are opposite to each other,

wherein the second input circuit element has a second connection portion, a second extension portion, and a second external connection portion, the second extension portion is connected to the second connection portion and the second external connection portions, wherein the second connection portion is connected to the second end portion, the second external connection portion protrudes from the second side and is connected to the external driving power source,

wherein the output circuit element has a third connection portion, a third extension portion, and a third external connection portion, the third extension portion is connected to the third connection portion and the third external connection portion, wherein the third connection portion is connected to the third end portion, the third external connection portion protrudes from the second side and is connected to the external driving power source.

13 . The optical element driving mechanism as claimed in claim 6 , wherein the optical element driving mechanism further comprises a position sensing assembly, sensing a movement of the movable portion relative to the fixed portion, comprising:

a reference element, disposed on the movable portion; and

a position sensing element, disposed on the fixed portion and connected to a sensing circuit assembly,

wherein the sensing circuit is disposed on the fixed portion and comprises a plurality of circuit elements, and the circuit elements protrude from the first side of the fixed portion and are connected to an external power source.

14 . The optical element driving mechanism as claimed in claim 6 , wherein the first circuit element, the second circuit element, and the third circuit element respectively have at least one hole portion, wherein a plurality of positioning posts are disposed on the first side of the fixed portion, and the hole portions are engaged with the positioning posts.

15 . The optical element driving mechanism as claimed in claim 6 , wherein the first side of the fixed portion is provided with a plurality of groove structures, wherein the first circuit element, the second circuit element and the third circuit element are fixed on the groove structures by an adhesive element.

16 . The optical element driving mechanism as claimed in claim 1 , wherein the movable portion is formed by a combination of a first part and a second part.

17 . The optical element driving mechanism as claimed in claim 16 , wherein the first limiting element is integrally formed with the first part, and the second limiting element is integrally formed with the second part.

18 . The optical element driving mechanism as claimed in claim 1 , wherein the limiting assembly is made of non-metallic material.