CN209897142U

CN209897142U - Camera module

Info

Publication number: CN209897142U
Application number: CN201920283916.0U
Authority: CN
Inventors: 许杨柳; 邓爱国; 颜欢欢; 徐爱新
Original assignee: Kunshan Q Technology Co Ltd
Current assignee: Kunshan Q Technology Co Ltd
Priority date: 2019-03-06
Filing date: 2019-03-06
Publication date: 2020-01-03
Anticipated expiration: 2029-03-06

Abstract

The utility model discloses a camera module, including circuit board, photosensitive element, motor, camera lens, magnetism sense component and feedback magnet, this photosensitive element locates on this circuit board to with this circuit board electric connection, in this motor was located to this camera lens, this camera lens can reciprocate along the optical axis direction of this camera lens relatively this circuit board under the drive of this motor, and this magnetism sense component and this feedback magnet one of this circuit board fixed setting relatively, and this magnetism sense component and this feedback magnet another of this camera lens fixed setting relatively. The utility model discloses an among the camera module, the change of the magnetic field of measuring the feedback magnet is felt through the magnetism of measuring the magnetism and feels the component changes, and then obtains the position change of camera lens and lens holder and feeds back to the motor, from this realization to the closed-loop control of motor, consequently, this camera module has the precision higher, the reliability is higher, low-power consumption, high response frequency, low-cost characteristics.

Description

Camera module

Technical Field

The utility model relates to an imaging technology field, in particular to camera module.

Background

At present, camera modules are commonly installed on electronic products such as mobile phones, cameras, computers, and the like, and the demand for the camera modules is increasing. The camera module comprises a fixed-focus camera module and a zooming camera module. In the zoom camera module, the lens can be driven to move by the voice coil motor, so that focusing and zooming are realized.

The voice coil motor of the zoom camera module has two types, namely an open-loop motor and a closed-loop motor. The open-loop motor changes the magnetic field force through the magnitude of the current so as to enable the motor to push the lens to carry out displacement focusing, but the current input by the motor outputs displacement, no feedback process exists, errors exist, and the accuracy is insufficient. The Hall chip is additionally arranged in the closed-loop motor, the Hall chip can sense the actual displacement of the lens, the motor can continuously adjust the motor according to the feedback of the Hall chip, and the position of the lens is adjusted, so that the actual position of the lens is consistent with the input position. However, the hall sensor has problems of low sensitivity, susceptibility to stress, temperature, and the like, and large power.

SUMMERY OF THE UTILITY MODEL

In view of this, the utility model provides a camera module that precision is higher and sensitivity and reliability are higher.

A camera module comprises a circuit board, a photosensitive element, a motor, a lens, a magnetic induction element and a feedback magnet, wherein the photosensitive element is arranged on the circuit board and is electrically connected with the circuit board, the lens is arranged in the motor, the lens can move up and down along the optical axis direction of the lens relative to the circuit board under the driving of the motor, one of the magnetic induction element and the feedback magnet is fixedly arranged relative to the circuit board, and the other of the magnetic induction element and the feedback magnet is fixedly arranged relative to the lens.

In an embodiment of the present invention, the magnetic induction element is a tunneling magneto-resistance element.

In an embodiment of the invention, the camera module further includes a base, the base is disposed on the circuit board, and the motor is disposed on the base.

The embodiment of the present invention provides a motor, which comprises a support, a lens holder, a magnet and a coil, wherein the support is fixed on the base, the lens holder can move relative to the support along the optical axis of the lens, the magnet is disposed on the support, and the coil is disposed on the lens holder.

In an embodiment of the present invention, the magnetic induction element is fixedly disposed relative to the base, and the feedback magnet is fixedly disposed relative to the lens.

In an embodiment of the present invention, the magnetic induction element is disposed on the circuit board, and the feedback magnet is disposed on the coil.

In the embodiment of the present invention, a boss is formed on the inner wall of the base, a containing cavity is formed between the boss and the circuit board, and the photosensitive element is located in the containing cavity.

In the embodiment of the present invention, the boss is recessed toward one side of the circuit board, so that the base forms an accommodating groove above the boss; the camera module further comprises an optical filter, the optical filter is located in the accommodating groove, the photosensitive element is arranged between the optical filter and the circuit board, and the photosensitive element and the optical filter are located on an optical axis of the lens.

In an embodiment of the present invention, the magnetic induction element is located in the accommodating cavity of the base.

In an embodiment of the present invention, the photosensitive element is electrically connected to the circuit board through a wire.

The utility model discloses an among the camera module, the change of the magnetic field of measuring the feedback magnet is felt through the magnetism of measuring the magnetism and feels the component changes, and then obtains the position change of camera lens and lens holder and feeds back to the motor, from this realization to the closed-loop control of motor, consequently, this camera module has the precision higher, the reliability is higher, low-power consumption, high response frequency, low-cost characteristics.

Drawings

Fig. 1 is a schematic cross-sectional view of a camera module according to an embodiment of the present invention.

Fig. 2 is a top view of the camera module shown in fig. 1.

Detailed Description

In order to make the objects, technical solutions and advantages of the present invention clearer, embodiments of the present invention will be further described below with reference to the accompanying drawings.

As shown in fig. 1 and fig. 2, the camera module according to an embodiment of the present invention includes a circuit board 11, a photosensitive element 13, a base 15, an optical filter 17, a motor 19, a lens 21, a magnetic sensor 23, and a feedback magnet 25.

The circuit board 11 may be a flexible circuit board, a flexible-rigid board, or a printed circuit board, and is used to connect the camera module with an external circuit, so as to implement input and output of the camera module.

The photosensitive element 13 is disposed on the circuit board 11 and electrically connected to the circuit board 11. The photosensitive element 13 is located in the base 15. Specifically, the photosensitive element 13 is electrically connected to the circuit board 11 through a wire 27. Specifically, the wires 27 are formed by bonding gold wires. Specifically, the photosensitive element 13 may be a CCD (charge coupled device) image sensor or a CMOS (Complementary Metal Oxide Semiconductor) image sensor.

The base 15 is arranged on the circuit board 11, the accommodating cavity 152 is formed in the base 15, and the photosensitive element 13 is located in the accommodating cavity 152. Specifically, a boss 154 is formed on the inner wall of the base 15, and the accommodation chamber 152 may be formed between the boss 154 and the circuit board 11. More specifically, the boss 154 is recessed toward the side of the wiring board 11, so that the base 15 forms a receiving groove 156 above the boss 154.

The filter 17 is also arranged in the base 15, the light-sensitive element 13 is arranged between the filter 17 and the circuit board 11, and the light-sensitive element 13 and the filter 17 are positioned on the optical axis of the lens 21. Specifically, the filter 17 is disposed above the boss 154 and in the receiving groove 156, it is understood that the filter 17 can also be disposed below the boss 154, and is not limited herein.

The motor 19 is provided on the base 15. The motor 19 includes a holder fixed to the base 15, a lens holder movable relative to the holder in the optical axis direction of the lens 21, a magnet 192 provided on the holder, and a coil 194 provided on the lens holder. When focusing is needed, the coil 194 is electrified, and when the electrified coil 194 passes through the magnetic field of the magnet 192, a force perpendicular to the magnetic field line is generated, namely, a force for moving the lens support upwards or downwards is generated, so that the lens support is driven to move up and down to change the focal length, and the purpose of clearing images is achieved.

Specifically, in the present embodiment, four magnets 192 are disposed around the coil 194 at intervals. The coil 194 forms a complete turn in the circumferential direction.

The motor 19 further includes an upper spring, a lower spring and a housing, the upper spring is disposed between the housing and the lens holder, and the lower spring is disposed between the support and the lens holder.

The lens 21 is disposed in a lens holder of the motor 19 to move up and down with the force generated by the coil 192. It is understood that the lens holder may be integrally formed with the lens 21.

The magnetic induction element 23 is provided on the circuit board 11. Specifically, the magnetic induction element 23 is located in the accommodation cavity 152 of the base 15. The Magneto-inductive element 23 is a tmr (tunnel Magneto resistance) element, i.e., a tunneling Magneto-resistance element. It will be appreciated that the magnetically susceptible elements 23 may also be provided on the base 15 or on the support of the motor. The magnetic induction element 23 is arranged on the circuit board 11, so that the transmission of the electric signals between the magnetic induction element 23 and the circuit board 11 can be realized more conveniently without other connecting leads.

The feedback magnet 25 is provided on the coil 194. It is understood that the feedback magnet 25 may be provided on the lens holder or lens 21 as long as it can move up and down along with the lens 21. It is understood that the magnetic induction element 23 may be provided on the coil 194 and the feedback magnet 25 may be provided on the circuit board 11, as long as the magnetic induction element 23 and the feedback magnet 25 move up and down relatively with the up and down movement of the lens 21.

When the camera module is focused, the force generated by the coil 194 drives the lens holder and the lens 21 to move up and down together, and at the same time, the feedback magnet 25 also moves up and down along with the force, and the magnetic field of the feedback magnet 25 sensed by the magnetic sensor 23 changes along with the change of the position of the feedback magnet 25, so that the magnetic resistance of the magnetic sensor 23 changes. Thus, the change of the magnetic field of the feedback magnet 25 can be measured by measuring the change of the magneto-resistance of the magneto-resistive element 23, and the position change of the lens 21 and the lens holder can be obtained and fed back to the motor 19, thereby realizing the closed-loop control of the motor 19. The magnetic induction element 23 has the characteristics of miniaturization, low cost, low power consumption, high integration, high response frequency and high sensitivity, and therefore, the camera module has the characteristics of higher precision, higher reliability, low power consumption, high response frequency and low cost.

Specifically, in the magnetoresistive effect of the magnetic inductance element 23, the spin polarizability P of the ferromagnetic layer electrodes is:

P＝N↑-N↓/(N↑+N↓), (1)

and N ↓andN ↓arerespectively the state density of the spin-up and spin-down electrons at the Fermi surface of the ferromagnetic metal. When the applied magnetic field is changed, the density of states of spin-up and spin-down electrons also changes.

As the Julliere model can obtain the TMR as follows:

TMR＝2P1P2/(1-P1P2)， (2)

where P1 and P2 are the spin polarizabilities of the effective electron transport state densities of the left and right ferromagnetic layers, respectively.

It can be seen that the magnitude of the magneto-resistance can be calculated from the above formula (1) and formula (2).

The preferred embodiments of the present invention have been described in detail with reference to the accompanying drawings, but the present invention is not limited to the details of the above embodiments, and the technical concept of the present invention can be within the scope of the present invention, and can be modified to various simple variants, and these simple variants all belong to the protection scope of the present invention. The various features described in the foregoing detailed description may be combined in any suitable manner without departing from the scope of the invention. In order to avoid unnecessary repetition, the present invention does not separately describe various possible combinations.

Claims

1. A camera module is characterized by comprising a circuit board (11), a photosensitive element (13), a motor (19), a lens (21), a magnetic induction element (23) and a feedback magnet (25), wherein the photosensitive element (13) is arranged on the circuit board (11) and is electrically connected with the circuit board (11), the lens (21) is arranged in the motor (19), the lens (21) can move up and down along the optical axis direction of the lens (21) relative to the circuit board (11) under the driving of the motor (19), one of the magnetic induction element (23) and the feedback magnet (25) is fixedly arranged relative to the circuit board (11), and the other one of the magnetic induction element (23) and the feedback magnet (25) is fixedly arranged relative to the lens (21).

2. The camera module as claimed in claim 1, wherein the magneto-inductive element (23) is a tunneling magneto-resistive element.

3. The camera module of claim 1, further comprising a base (15), wherein the base (15) is disposed on the circuit board (11), and the motor (19) is disposed on the base (15).

4. The camera module as claimed in claim 3, wherein the motor (19) comprises a holder, a lens holder, a magnet (192) and a coil (194), the holder is fixed to the base (15), the lens holder is movable relative to the holder along an optical axis of the lens (21), the magnet (192) is disposed on the holder, and the coil (194) is disposed on the lens holder.

5. The camera module as claimed in claim 4, wherein the magnetic sensor element (23) is fixedly disposed with respect to the base (15), and the feedback magnet (25) is fixedly disposed with respect to the lens (21).

6. The camera module as claimed in claim 5, wherein the magneto-inductive element (23) is disposed on the circuit board (11), and the feedback magnet (25) is disposed on the coil (194).

7. The camera module as claimed in claim 3, wherein a protrusion (154) is formed on an inner wall of the base (15), a receiving cavity (152) is formed between the protrusion (154) and the circuit board (11), and the photosensitive element (13) is located in the receiving cavity (152).

8. The camera module as claimed in claim 7, wherein the protrusion (154) is recessed toward a side of the circuit board (11) such that the base (15) forms a receiving groove (156) above the protrusion (154); the camera module further comprises an optical filter, the optical filter (17) is located in the accommodating groove (156), the photosensitive element (13) is arranged between the optical filter (17) and the circuit board (11), and the photosensitive element (13) and the optical filter (17) are located on an optical axis of the lens (21).

9. The camera module as claimed in claim 7, wherein the magnetic sensor element (23) is located in the receiving cavity (152) of the base (15).

10. The camera module as claimed in claim 1, wherein the photosensitive element (13) is electrically connected to the circuit board (11) through a conductive wire (27).