lens driver

Abstract

The invention discloses a lens driving device, which includes a first yoke ring, a spacer, a first reed, a lens carrier, a magnet, a second reed, and a second yoke ring; The second yoke ring yoke lobes are symmetrically arranged in positions equal to the number corresponding to the electromagnetic coupling insertion slots of the lens carrier, and the yoke lobes of the second yoke ring protrude vertically toward the yoke ring cavity to form a magnetic The yoke lobe is coupled and is rectangular, the second yoke ring yoke lobe extends into the electromagnetic coupling insertion groove without contact and its coupling plane faces the magnetic pole coupling surface of the magnet; the first yoke ring and the second yoke ring are inlaid The combined placement and the magnet form a composite magnetic field at the corresponding position of the corresponding coil. The invention can ensure that the gas field in each air gap is uniform to the greatest extent.

Description

technical field [0001] The invention belongs to the technical field of miniature linear motors, and specifically relates to a lens driving device, and its application is not limited to high-pixel miniature digital cameras with auto-focus function. Background technique [0002] The principle of the aforementioned lens driving device comes from the working principle of the horn, that is, the coil is in the magnetic field generated by the permanent magnet. When the current passes through the coil, the coil induces electromagnetic force and is displaced, and the displacement of the coil drives the displacement (vibration) of the sound disc. . In the lens driving device, the displacement of the coil drives the displacement of the lens carrier on which the lens is placed, so that the lens moves back and forth to achieve the purpose of focusing. [0003] In recent years, with the development of CMOS technology of image sensors used in miniature cameras, high-pixel and ultra-high-p...

AI Technical Summary

Problems solved by technology

However, there are the following shortcomings: First, through the interpretation of the description of the patent application, it can be known that a group of magnets cooperate with the first yoke ring and the second yoke ring to form a bending magnetic field in the yoke ring cavity, although the magnetic field distribution Uniformly increases the effective length of the coil to obtain a higher electromagnetic induction force, but because there is no yoke lobe close to the magnet in the yoke ring cavity, the magnetic field air gap is large, and the common knowledge, the reluctance will double and cause the magnetic flux to increase. double attenuation, so it will limit the effectiveness of coil electromagnetic induction; second, because the strength and uniformity of the curved magnetic field are greatly affected by the physical size of the magnet, the first yoke ring and the second yoke ring, once its physical size A weak deviation will cause a large deviation in the uniformity of the magnetic field intensity. At the same time, the strength of the curved magnetic field in the air gap is extremely sensitive to the distance. Once the center position of the coil is slightly deviated in the assembly , the symmetry of the four component forces of the electromagnetic induction force coupled with a group of magnets (generally four, and symmetrically arranged at the four corners of the first yoke ring cavity) will seriously deteriorate, eventually causing the lens The optical axis of the carrier is degraded due to over-limit deviation; thirdly, the lens driving method is from zero distance (focus + ∞ position) to the maximum distance (focus closest position), and every time the focus is driven, it must be driven in full stroke, so, Long focusing time

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