lens driver

Abstract

The invention relates to a lens driving device and belongs to the technical field of micro-cameras. The lens driving device comprises a first magnetic yoke ring, an insulation sheet, a first spring piece, a gasket, a lens carrier, a coil, a group of magnets and a second spring piece, wherein the outer profile of the first magnetic yoke ring is rectangular or circular, the insulation sheet is matched with a magnetic yoke ring cavity, the first spring piece and the gasket are placed in the magnetic yoke ring cavity, the lens carrier is provided with a lens placing cavity, the lens carrier and the coil are placed in the magnetic yoke ring cavity, and the second spring piece is placed in magnetic yoke ring cavity and provided with a group of third spring wires. The lens driving device has the advantages that a good even distribution effect is showed by the magnetic lines of the magnetic field generated by the magnets, an electromagnetic induction force of the coil obtained in an effective length range is enabled to be enlarged significantly, so that good driving characteristics are reflected, power driving power consumption can be reduced, assembly efficiency can be improved, the phenomenon that foreign bodies in the cavity drop on a sensor surface of a camera from lens carrier mating holes is avoided, wherein the phenomenon is caused by impact and vibration, so that image quality is ensured, harsh requirements of a lens optical axis degree can be met, and electromagnetic radiation generated by the coil can be prevented from affecting surrounding components.

Description

technical field [0001] The invention belongs to the technical field of miniature cameras, and in particular relates to a lens driving device, which is applied to a high-pixel miniature digital camera with an automatic focus function. Background technique [0002] The aforementioned miniature digital cameras are not limited to applications such as mobile phones, computers, automobiles, security, digital video cameras, and MP3 players, etc., and the movement of the lens is usually performed by a motor as a driving device (the industry is accustomed to call it a lens driving device). The motor generally uses a voice coil motor (English name: Voice Line Motor, referred to as VCM). The principle of the voice coil motor driving the lens movement comes from the coil in the speaker in the magnetic field generated by the permanent magnet. When the current passes through the coil, the coil induces the electromagnetic field. Force and displacement, and the displacement of the coil driv...

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Problems solved by technology

[0005] Typical publications such as the "lens driving device" recommended by the invention patent application publication number CN102223047A, although the patent application scheme fulfills the invention objectives of the 0007 to 0008 columns of the specification and the 0012 column, but there are the following shortcomings: First, through the interpretation of the specification of the patent application, it can be seen that the electromagnetic coupling between the yoke ring 1 (the patent is called a clamp) and the magnet 7 (the patent is called a magnet) is Figure 4 In the state shown, because the magnetic force lines of the magnetic field generated by this electromagnetic coupling are not parallel and uniform, there is a lot of magnetic flux leakage, resulting in a small effective electromagnetic induction force obtained within the effective length of the coil; During the installation process, any installation step needs to be fixedly connected, so the installation process is cumbersome, labor-intensive and time-consuming, which affects installation efficiency; Penetrate into the internal space from the side part where the yoke ring and the base are combined, but cannot prevent impurities from entering the internal space from the entrance hole on the upper surface of the yoke ring; Fourth, the optical axis of the coil tube coupled with the lens module It is difficult to achieve a satisfactory level, because the outer peripheral ends of the spring wires of the upper and lower springs disclosed in the patent are respectively positioned on the inner side of the upper surface of the yoke ring and between the bushing and the base, and because no matter what process is used, each zero The deviation of the processing size of the parts and the deviation of the assembly gap are inevitable, so that there is an undesirable but inevitable deviation in the assembly concentricity of the upper and lower springs, which eventually leads to the optical axis of the coil tube coupled with the lens module. Overrun deviation

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