TECHNICAL FIELD

The present disclosure relates to the technical field of lens optical imaging, in particular to a lens module.

BACKGROUND

In recent years, a high-performance lens module is installed on portable terminals such as smart phones and tablet computers. Generally, the high-performance lens module has auto focusing (AF) and optical image stabilization (OIS) functions. The high-performance lens module needs to move a lens in the direction of an optical axis of the lens during auto-focusing, and needs to move the lens in a direction perpendicular to the direction of the optical axis of the lens when implementing the optical image stabilization function. In the existing technology, a shape memory alloy wire is used to drive a lens base to move in a direction perpendicular to the direction of the optical axis of the lens to realize image stabilization. A drive end of a shape memory alloy wire could come off during operation, thus the drive end is generally glued to strengthen fixing it, one defect of which, however, is that when one group of shape memory alloy wires drives the lens base to move in one direction, a great stress can be caused to other groups of shape memory alloy wires, especially to the group of shape memory alloy wires disposed in the opposite, to which the stress is greater, thereby reducing service life of the shape memory alloy wires.

Therefore, it is necessary to provide an improved lens module to solve the above problem.

SUMMARY

The present disclosure seeks to provide a lens module to solve the technical problem of avoiding greater stress when strengthening fixing a shape memory alloy wire.

The technical solution of the present disclosure is as follows: a lens module, including a base, a lens base, a holding assembly configured to hold the lens base, and several groups of shape memory alloy wires configured to drive the lens base to move in a direction perpendicular to a direction of an optical axis of a lens; the lens base being suspended within the base by the holding assembly; each group of the shape memory alloy wires including two ends fixed to one of the base and the lens base and a drive end located between the two ends, the other one of the base and the lens base being provided with a fixing member, the drive end being connected to the fixing member, and the fixing member being provided with a flapper configured to prevent the drive end from escaping the fixing member.

Further, the fixing member includes an attaching surface attaching to the drive end, and the flapper includes an installation section installed to the fixing member and a shielding section extending from the installation section and beyond the attaching surface.

Further, the installation section and the shielding section are integrally formed.

Further, an angle α is provided between the shielding section and the attaching surface, where 0°<α≤90°.

Further, the attaching surface is an arc surface.

Further, the flapper is a semicircle and has an arc side surface located at a side of a central axis of the fixing member, the side being away from the end. Alternatively, a part of the flapper located at the side of the central axis of the fixing member, the side being away from the end, is rectangular. The flapper has a long side surface located at the side of the central axis of the fixing member, the side being away from the end, and two short side surfaces respectively extending from two ends of the long side surface to the side where the end locates, the long side surface and the two short side surfaces being provided alternately. The length of the long side surface is defined as L and a distance between the two ends of a shape memory alloy wire is defined as D, where L/D≥1/5.

Further, either one of the fixing member and the installation section is provided with a clipping hole, the other one of the fixing member and the installation section is provided with a protruding pillar, and the flapper is installed to the fixing member by engaging the protruding pillar with the clipping hole.

Further, the protruding pillar is provided on the fixing member. A fixing surface of the protruding pillar, the fixing surface being away from the end, is set aligned with the attaching surface. The fixing member further includes a body, and the protruding pillar and the body are integrally formed.

Further, the end of the shape memory alloy wire is fixed to the base. The base includes a substrate and a frame fixed to the substrate, the substrate and the frame forming an accommodating space configured to accommodate the lens base. The frame is rectangular, and includes four side plates disposed circumferentially, the end of the shape memory alloy wires is fixed to one end of the side plate, the end facing the substrate. The fixing member is installed on the lens base, the body extends from the lens base towards the substrate, and the attaching surface is provided at a side of the body.

Further, two fixing grooves are provided at an end of each of the side plates, the end facing the substrate. The lens module further includes a plurality of conductive members, each conductive member is fixed in one respective fixing groove, and the two ends of each group of the shape memory alloy wires are respectively fixed to two of the conductive members of the same side plate. The base further includes a circuit board, and the circuit board is fixed to the substrate at the side facing the lens base. The conductive member is electrically connected with the circuit board, and there is a gap between the flapper and the circuit board.

The present disclosure is advantageous in: by adding a flapper to the fixing member, it may effectively prevent the shape memory alloy wires from escaping the fixing member, thereby strengthening fixing of the shape memory alloy wires in the direction of the optical axis; and when one group of shape memory alloy wires operates, it does not result in extra stress to other groups of shape memory alloy wires, thereby prolonging service life of the shape memory alloy wires.

