Lens driving device

Abstract

The invention provides a lens driving device, which comprises a fixed part, a moving part and a driving part; the fixed part comprises an iron case; the moving part comprises a lens bracket; the driviThe invention provides a lens driving device, which comprises a fixed part, a moving part and a driving part; the fixed part comprises an iron case; the moving part comprises a lens bracket; the driving part comprises a plurality of magnetic irons which are fixed on one of the iron case and the lens bracket; the plurality of magnetic irons are divided into at least two layers along the axial direcng part comprises a plurality of magnetic irons which are fixed on one of the iron case and the lens bracket; the plurality of magnetic irons are divided into at least two layers along the axial direction of the lens, and divided into a plurality of groups along the circumferential direction of the lens; each magnetic iron is polarized along the radial direction of the lens; the magnetic irons oftion of the lens, and divided into a plurality of groups along the circumferential direction of the lens; each magnetic iron is polarized along the radial direction of the lens; the magnetic irons ofeach layer form 2N magnetic poles, a plurality of magnetic loops are formed on a plane which is vertical to the axial direction of the lens, and N is an integral number which is not less than 1; the peach layer form 2N magnetic poles, a plurality of magnetic loops are formed on a plane which is vertical to the axial direction of the lens, and N is an integral number which is not less than 1; the polarities of two adjacent magnetic irons in one group are opposite, thus forming a magnetic loop on the plane which is parallel to the axial direction of the lens; and the driving part also comprisesolarities of two adjacent magnetic irons in one group are opposite, thus forming a magnetic loop on the plane which is parallel to the axial direction of the lens; and the driving part also comprisesat least two coils which correspond to the plurality of magnetic irons and are fixed on one of the iron case and the lens bracket. As each coil is positioned in a plurality of magnetic loops, the magnat least two coils which correspond to the plurality of magnetic irons and are fixed on one of the iron case and the lens bracket. As each coil is positioned in a plurality of magnetic loops, the magnetic density where the coils are positioned is greatly strengthened, the magnetic leakage is reduced, the EMI is improved and the magnetic field utilization ratio is increased.etic density where the coils are positioned is greatly strengthened, the magnetic leakage is reduced, the EMI is improved and the magnetic field utilization ratio is increased.

Description

technical field [0001] The invention belongs to the technical field of imaging, and in particular relates to a lens driving device. Background technique [0002] Video electronic products such as digital cameras, digital video cameras, mobile phones with camera functions, and notebook computers with cameras are usually equipped with lenses. A commonly used lens driving method in the prior art is to drive the lens through a coil and a magnet to generate electromagnetic force. The lens moves on the optical axis. [0003] figure 1 Shown is a lens driving device in the prior art, which includes an iron shell 11, a magnet 12, a coil 13 and a lens holder 14, the magnet 12 is fixed to the iron shell 11 as a fixed part, and the coil 13 is fixedly sleeved on the lens The outside of the frame 14 is fixed as a moving part, and the moving part can move relative to the fixed part. The iron shell 11 includes an outer ring 111, an inner ring 112 and a yoke 113, the outer ring 111 and ...

AI Technical Summary

Problems solved by technology

[0004]The magnetic flux direction of the magnet 12 is Figure 1, as shown in the direction of the arrow, because the lens holder 114 is a moving part, therefore, the inner ring 112 of the iron shell must be shorter than the length of the outer ring 111 and the magnet 12, and the magnet 12 produces A large part of the magnetic flux cannot enter the inner ring 112, and this part of the magnetic flux that fails to enter the inner ring 112 encounters a large reluctance, so the magnetic field where the corresponding coil part is located is relatively weak, and the utilization rate of the magnetic field is low

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