TWI472795B - Camera module - Google Patents

Description

Camera module

The present invention relates to the field of camera modules, and in particular, to a camera module having an optical image stabilization function.

The camera module controls the length of time that the light is projected onto the image sensor by the shutter. For example, when the shutter speed is 1/2 second, the image sensor sensing time is 1/2 second, if within 1/2 second. Due to the shaking, the same beam of light moves on the image sensor, and the image sensor records the trajectory of the light, making the captured photo obscure. In order to compensate for the amount of light offset caused by jitter, camera modules using image stabilization systems to prevent jitter began to appear in the 1990s. For details, please refer to the paper "Optical image stabilization for digital cameras" published by Cardani B. et al., April 2006, Control Systems Magazine, IEEE (Volume 26, Issue 2, Page(s): 21-22).

The anti-shake technology of the camera module is mainly divided into two categories: electronic anti-shake and optical anti-shake. Among them, the electronic image stabilization mainly refers to the use of the camera module to force the sensitivity of the image sensor while speeding up the shutter and analyzing the image obtained on about 2/3 of the area on the image sensor, and then using the edge image. The anti-shake technique is compensated, but since some image information is inevitably discarded during image processing, the electronic image stabilization technology actually reduces the efficiency of the image sensor.

Optical anti-shake technology can be divided into two types: lens anti-shake and imaging device anti-shake and anti-shake. Lens Anti-shake mainly refers to setting a special anti-shake compensation lens group in the lens module. According to the direction and degree of shaking of the camera module, the lens group can be adjusted to adjust the position and angle accordingly, so that the optical path is stable, but adding the compensation lens group will increase the camera. The total height of the module in the direction of the optical axis is not conducive to the thinness of the camera module. Anti-shake of the imaging device mainly refers to changing the position or angle of the image sensor to maintain imaging stability after sensing the camera module jitter, but the anti-shake of the imaging device requires a high-precision mechanism to change the position or angle of the image sensor, correspondingly The ground greatly increases the manufacturing cost of the camera module.

In view of this, it is necessary to provide a camera module that does not require a special anti-shake compensation lens group and has a relatively simple structure and a low cost.

A camera module will be described below with specific embodiments.

A camera module includes a circuit board, an image sensor disposed on the circuit board, a processor, and a displacement sensor for sensing an offset of the image sensor relative to an object to be photographed, and relative image sensing The lens module is set. The lens module has a first side and a second side. The camera module further includes a first wire, a second wire, and a plurality of flexible supports. A first magnet and a second magnet are respectively fixed on the first side surface and the second side surface. The first wire and the second wire are respectively disposed opposite to the first magnet and the second magnet and are fixed to the image sensor. The first wire and the second wire are both parallel to the optical axis of the lens module. The direction of the magnetic field of the first magnet and the second magnet is at an angle of between 60 and 150 degrees. The lens module is supported on the circuit board by the plurality of flexible supports. The processor controls the current in the first wire and the second wire according to the offset, so that the lens module is subjected to the reaction force of the ampere force by the first magnet and the second magnet, thereby causing the object to be photographed through the shooting time. The lens module imaging is always in the same position as the image sensor.

A camera module includes a circuit board, an image sensor disposed on the circuit board, a processor, and a displacement sensor for sensing an offset of the image sensor relative to an object to be photographed, and relative image sensing The lens module is set. The lens module has an annular upper surface and a lower surface, and a side surface connected between the upper surface and the lower surface. The camera module further includes a first wire, a second wire, a third wire and a fourth wire, and a plurality of flexible supports. The first magnet, the second magnet, the third magnet, and the fourth magnet are disposed at equal intervals of 90 degrees in the circumferential direction of the side surface. The first wire, the second wire, the third wire and the fourth wire are respectively disposed opposite to the first magnet, the second magnet, the third magnet and the fourth magnet and are fixed to the image sensor. The plurality of first wires, second wires, third wires and fourth wires are parallel to an optical axis of the lens module. The first magnet is perpendicular to the direction of the magnetic field of the second magnet, and the third magnet is perpendicular to the direction of the magnetic field of the fourth magnet. The lens module is supported on the circuit board by the plurality of flexible supports. The processor controls the current in the first wire, the second wire, the third wire, and the fourth wire according to the offset, so that the lens module is received by the first magnet, the second magnet, the third magnet, and the fourth magnet Ampere's reaction force movement, so that the subject being photographed through the lens module during the shooting time is always in the same position of the image sensor.

Compared with the prior art, the camera module of the technical solution supports the lens module by using a flexible support connected to the circuit board and the lens module, and is fixed to the first side, the second side or the side of the lens module. At least two magnets and at least two sets of wires parallel to the optical axis of the lens module respectively generate an ampere force in a magnetic field formed by the at least two magnets thereof to drive the lens module to move in two perpendicular axes perpendicular to the optical axis thereof And controlling, by the processor, the current supplied to the corresponding wire to accurately control the magnitude of the ampere force generated by the at least two sets of wires, thereby adjusting the offset of the camera module due to the jitter, so that the lens module is opposite to the lens module The image sensor moves to eliminate the image blur caused by the movement of the image sensor, and achieves the purpose of anti-shake, and does not need to be set. The special anti-shake compensation lens set can reduce the height of the camera module in the optical axis direction, which is beneficial to the thinning of the camera module and saves the cost of using the anti-shake compensation lens group.

100, 200‧‧‧ camera module

30, 230‧‧‧ circuit board

20, 220‧‧‧ image sensor

70, 270‧‧‧ displacement sensor

80, 280‧‧‧ processor

10, 210‧‧‧ lens module

60, 260‧‧‧ flexible support

41, 241‧‧‧ first magnet

42, 242‧‧‧ second magnet

51, 251‧‧‧ first wire

52, 252‧‧‧second wire

32‧‧‧ Surface

22‧‧‧Image sensing surface

11‧‧‧ first side

12‧‧‧ second side

13‧‧‧ third side

14‧‧‧ fourth side

15, 201‧‧‧ upper surface

16, 202‧‧‧ lower surface

102‧‧‧ points

104‧‧‧

204‧‧‧ side

243‧‧‧ Third magnet

244‧‧‧fourth magnet

253‧‧‧ Third wire

254‧‧‧fourth wire

FIG. 1 is a schematic diagram of a camera module provided by a first embodiment of the present technical solution.

2 is a schematic view showing the camera module of the first embodiment in an original state.

FIG. 3 is a schematic diagram showing a jitter state of the camera module of the first embodiment.

4 is a schematic diagram of the camera module of the first embodiment correcting the jitter state.

FIG. 5 is a schematic diagram of a camera module provided by a second embodiment of the present technical solution.

The camera module of the present technical solution will be further described in detail below with reference to the accompanying drawings and the embodiments.

Referring to FIG. 1 , an optical image stabilization camera module 100 according to a first embodiment of the present invention includes a circuit board 30 , an image sensor 20 , a displacement sensor 70 , a processor 80 , a lens module 10 , and a flexible device . The support body 60, the first magnet 41, the second magnet 42, the first wire 51, and the second wire 52.

The circuit board 30 has a surface 32. The image sensor 20, the displacement sensor 70 and the processor 80 are disposed on the surface 32, and the image sensor 20 and the displacement sensor 70 are fixed relative to the circuit board 30. The lens module 10 is disposed opposite to the image sensor 20. The image sensor 20 has an image sensing surface 22 that is perpendicular to the optical axis of the lens module 10. One end of the flexible support body 60 is connected to the surface 32, and the other end is connected to the lens module 10 to flexibly support the lens module 10 on the circuit board 30. When the flexible support 60 is not deformed, the center of the image sensing surface 22 is located on the extension line of the optical axis of the lens module 10. The first magnet 41 and the second magnet 42 are fixed to the lens module 10, and the first wire 51 and the second wire 52 are respectively opposite to the first magnet 41. The second magnet 42 is disposed, and when a current is passed through the first wire 51 and the second wire 52, the first magnet 41 and the second magnet 42 are subjected to a reaction force of the ampere force.

The displacement sensor 70 is used to sense the offset of the image sensor 20 relative to the object being photographed. In this embodiment, the displacement sensor 70 is an interferometric fiber optic gyroscope. When operating, it emits a detection beam in different directions, and causes a plurality of different detection beams to advance in the optical loop. The optical loop is a ring. When the optical path of the detecting beam moves along with the object to be sensed, the optical path of the detecting beam in the optical loop is changed relative to the optical path of the optical loop, and the optical path of the detecting beam in the optical loop changes, thereby making the difference Interference is generated between the detection beams, and the rotation speed of the loop can be measured by the interference to detect the jitter of the camera module 100. Specifically, a direction perpendicular to the optical axis of the lens module 10 and perpendicular to the first side surface 11 is defined as a first axial direction X, and a direction perpendicular to the optical axis of the lens module 10 and perpendicular to the second side surface 12 is defined as a second direction. The axial direction Y, which is parallel to the optical axis of the lens module 10, is defined as the third axial direction Z. The displacement sensor 70 is mainly used to sense the offset of the camera module 100 itself in the first axial direction X and the second axial direction Y perpendicular to the optical axis direction when the camera module 100 is shaken. Of course, the displacement sensor 70 can also be other sensors with displacement change sensing functions. For example, the displacement sensor 70 can also be an infrared sensor.

The processor 80 is electrically connected to the displacement sensor 70, and is configured to control the current in the first wire 51 and the second wire 52 according to the offset sensed by the displacement sensor 70, so that the lens module 10 is The first magnet 41 and the second magnet 42 are subjected to the reaction force of the ampere force to move the lens module 10 relative to the image sensor 20 to eliminate image blur caused by the camera module 100 shaking.

In this embodiment, the lens module 10 has a rectangular shape and has a first side surface 11, a second side surface 12, a third side surface 13, a fourth side surface 14, an upper surface 15 and a lower surface 16. The following table The surface 16 is opposite to the image sensor 20, and the upper surface 15 is away from the image sensor 20 with respect to the lower surface 16, that is, the upper surface 15 is located on the object side of the lens module 10, and the lower surface 16 is located on the image side of the lens module 10. The first side surface 11, the second side surface 12, the third side surface 13 and the fourth side surface 14 are vertically connected between the upper surface 15 and the lower surface 16. In this embodiment, the first side surface 11 and the second side surface 12 are perpendicular to each other, the third side surface 13 and the fourth side surface 14 are perpendicular to each other, and the third side surface 13 is parallel to the first side surface 11. The first magnet 41 and the second magnet 42 are fixed to the first side surface 11 and the second side surface 12, respectively. The direction of the magnetic field of the first magnet 41 and the second magnet 42 is at an angle of between 60 and 150 degrees. In this embodiment, the magnetic field directions of the first magnet 41 and the second magnet 42 are perpendicular to each other. Each of the first wire 51 and the second wire 52 is plural and parallel to the optical axis of the lens module 10. Both ends of the first wire 51 and the second wire 52 are electrically connected to the circuit board 30 by additionally disposed wires, and the processor 80 can control the magnitude of the current passing through the wire.

The flexible support body 60 includes four flexible support lines. In the undeformed state, the four flexible support lines are parallel to the optical axis of the lens module 10, and one end thereof is respectively opposite to the first side 11, the second side 12, and the third side. 13 and the intersection of the fourth side 14 are connected. Of course, the flexible support wire can also be attached to the lower surface 16 of the lens module 10. The thickness setting of the flexible support line can be determined according to the quality of the lens module 10 itself. Generally, the flexible support 60 should be such that the lens module 10 does not touch the first wire 51 and the second wire 52 when the camera module 100 is vibrating, or the flexible support 60 is perpendicular to the optical axis of the lens module 10 The bending angle of the two perpendicular directions is preferably not more than 20 degrees.

The first wire 51 and the second wire 52 are disposed opposite to the first magnet 41 and the second magnet 42, respectively. In this embodiment, the first wire 51 and the second wire 52 are straight wires parallel to the optical axis of the lens module 10. In addition, the first wire 51, the second wire 52, and the circuit board 30 can be fixedly disposed in the lens holder (not shown) of the lens module 10, thereby making the The first wire 51 and the second wire 52 are not in the same position as the image sensor 20 packaged on the circuit board 30. In this embodiment, the N poles of the first magnet 41 and the second magnet 42 are respectively directed to the first wire 51 and the second wire 52, that is, the magnetic fields of the first magnet 41 and the second magnet 42 are perpendicular to each other. Therefore, when the first wire 51 and the second wire 52 are energized, they are respectively subjected to the ampere forces in two directions perpendicular to each other, so that the first magnet 41 and the second magnet 42 can drive the lens module under the reaction force of the Ampere force. 10 translation.

When the camera module 100 is used for photographing, the lens module 10 and the image sensor 70 can be relatively fixed by a positioning mechanism (for example, a motor-driven elastic piece) before the shutter is opened, so that the lens module 10 is closed at the shutter. The sway is not caused by the connection with the flexible support 60, that is, the lens module 10 is in the initial position. When the shooting is required, the positioning mechanism can be released, and the lens module 10 can be moved in translation.

Please refer to FIG. 2 , which is a schematic diagram of the lens module 10 when the shutter of the camera module 100 is opened, wherein the image point 104 of the object point 102 is at the center of the image sensor 20 . Referring to FIG. 3, if the camera module 100 is shaken in the first axial direction X, the displacement sensor 70 senses that the camera module 100 is offset by X ₁ in the first axial direction X. After the processor 80 obtains the offset information from the displacement sensor 70, the compensation component of the lens module 10 in the negative direction of the first axis X is X ₂ by calculation and analysis. The processor 80 can calculate the magnitude relationship of the current supplied to the first wire 51 and the second wire 52 respectively, so that the lens module 10 compensates the displacement amount in the first axial direction X by X ₂ in the same time t. At this time, since the N poles of the first magnet 41 and the second magnet 42 are respectively directed to the first wire 51 and the second wire 52, the direction of the urging force of the lens module 10 is the first axis X negative direction and the The two axial directions are negative. Thereby, the direction of the amperage of the first wire 51 is positive in the second axial direction Y, and the direction of the amperage of the second wire 52 is positive in the first axial direction X.

The algorithm for processor 80 to derive the magnitude of the supply current is as follows:

The compensation amount of the first axial X negative direction is: X ₂ = a ₁ t ² /2 = F ₁ t ² /2 m = B ₁ I ₁ L ₁ t ² /2 m, (1)

The compensation amount of the second axial Y negative direction is: Y ₂ = a ₂ t ² /2 = F ₂ t ² /2 m = B ₂ I ₂ L ₂ t ² /2 m, (2)

Wherein, a ₁ and a ₂ respectively represent accelerations of the lens module 10 in the first axial direction X and the second axial direction Y, and F ₁ and F ₂ respectively represent the lens module 10 in the first axial direction X and the second axial direction. Y is subjected to Ampere force, and B ₁ and B ₂ respectively indicate magnetic induction intensities of the first magnet 41 and the second magnet 42. I ₁ and I ₂ respectively indicate current intensities supplied to the first wire 51 and the second wire 52, L ₁ , L ₂ denotes the total length of the wires of the plurality of first wires 51 perpendicular to the direction of the magnetic field of the first magnet 41 and the total length of the wires of the plurality of second wires 52 perpendicular to the direction of the magnetic field of the second magnet 42 respectively, and m denotes the lens module 10 and the first The total weight of one magnet 41 and the second magnet 42.

From the formula (1) and the formula (2), I ₁ /I ₂ =X ₂ B ₂ L ₂ /Y ₂ B ₁ L ₁ .

Since X ₂ , Y ₂ , B ₁ , B ₂ , L ₁ , L ₂ , and m are all measurable parameters, the ratio of I ₁ to I ₂ can be obtained, and only the value of a current I ₁ can be set. Calculate the value of another current I ₁ and calculate the energization time t from equation (1) or equation (2). Therefore, the processor 80 can supply the current I _{1 of the} first wire 51 during the time t and the current I _{2 of the} second wire 52 during the time t. Therefore, the lens module 10 obtains the compensation displacement amount X _{2 in the} negative direction of the first axial direction X in time t to correct the jitter of the camera module 100. Referring to FIG. 4, after the compensation displacement X ₂ of the lens module 10, the image point 104 of the object point 102 is still at the center of the image sensor 20, that is, the image shift caused by the jitter is eliminated. It can be understood that the compensation in the Y direction is similar to the compensation in the X direction.

Referring to FIG. 5 , the camera module 200 provided by the second embodiment of the present invention is substantially the same as the camera module 100 provided by the first embodiment, except that the lens module 210 has a cylindrical shape and has a ring shape. The upper surface 201 and the lower surface 202, and the side surface 204 connected between the upper surface 201 and the lower surface 202.

The camera module 200 includes a first magnet 241, a second magnet 242, a third magnet 243, and a fourth magnet 244. The first magnet 241, the second magnet 242, the third magnet 243, and the fourth magnet 244 are fixed to the side surface 204 at equal intervals, that is, the first magnet 241, the second magnet 242, the third magnet 243, and the fourth magnet 244 are circumferentially oriented. They are distributed on the side surface 204 at intervals of 90 degrees. In this embodiment, since the side surface 204 of the lens module 10 is cylindrical, the first magnet 241, the second magnet 242, the third magnet 243, and the fourth magnet 244 are arc-shaped magnets that match the side surface 204.

The camera module 200 further includes a first wire 251, a second wire 252, a third wire 253, and a fourth wire 254 opposite to the first magnet 241, the second magnet 242, the third magnet 243, and the fourth magnet 244, respectively. The first wire 251, the third wire 252, the third wire 253 and the fourth wire 254 are both disposed in parallel with the optical axis of the lens module 210. The first wire 251, the second wire 252, the third wire 253 and the fourth wire 254 are both fixed relative to the image sensor 220. Of course, in order to cooperate with the first magnet 241, the second magnet 242, the third magnet 243, and the fourth magnet 244, the first wire 251, the second wire 252, the third wire 253, and the fourth wire 254 are arcs of four groups. A straight wire arranged in the shape of its opposite curved magnet.

The camera module 200 includes three flexible supports 260. The flexible support 260 is connected between the lens module 210 and the circuit board 230. The three flexible supports 260 are in the circumferential direction The lower surface 202 of the lens module 210 is connected to the 120 degree interval.

The processor 280 is disposed on the circuit board 230. The processor 280 is electrically connected to the displacement sensor 270 and the first wire 251, the second wire 252, the third wire 253 and the fourth wire 254.

In addition, the opposing magnets and wires of the camera module may have other shapes, and the wires only need to be parallel to the optical axis of the lens module, and the magnetic poles of the magnets may be opposite to the wires.

Compared with the prior art, the camera module of the technical solution supports the lens module by using a flexible support connected to the circuit board and the lens module, and is fixed to the first side, the second side or the side of the lens module. At least two magnets and at least two sets of wires parallel to the optical axis of the lens module respectively generate an ampere force in a magnetic field formed by the at least two magnets thereof to drive the lens module to move in two perpendicular axes perpendicular to the optical axis thereof And controlling, by the processor, the current supplied to the corresponding wire to accurately control the magnitude of the ampere force generated by the at least two sets of wires, thereby adjusting the offset of the camera module due to the jitter, so that the lens module is opposite to the lens module The image sensor moves to eliminate the image blur caused by the movement of the image sensor, and achieves the purpose of anti-shake. It does not need to provide a special anti-shake compensation lens group, which can reduce the height of the camera module in the optical axis direction, which is advantageous. The camera module is thinned and the cost of using the anti-shake compensation lens set is saved.

In summary, the present invention has indeed met the requirements of the invention patent, and has filed a patent application according to law. However, the above description is only a preferred embodiment of the present invention, and it is not possible to limit the scope of the patent application of the present invention. Equivalent modifications or variations made by persons skilled in the art in light of the spirit of the invention are intended to be included within the scope of the following claims.

100‧‧‧ camera module

30‧‧‧ boards

20‧‧‧Image Sensor

70‧‧‧ Displacement Sensor

80‧‧‧ processor

10‧‧‧Lens module

60‧‧‧Flexible support

41‧‧‧First magnet

42‧‧‧second magnet

51‧‧‧First wire

52‧‧‧second wire

32‧‧‧ Surface

22‧‧‧Image sensing surface

11‧‧‧ first side

12‧‧‧ second side

13‧‧‧ third side

14‧‧‧ fourth side

15‧‧‧Upper surface

16‧‧‧ Lower surface

Claims (9)

A camera module includes a circuit board, an image sensor disposed on the circuit board, a processor, and a displacement sensor for sensing an offset of the image sensor relative to an object to be photographed, and relative image sensing The lens module has an opposite upper surface and a lower surface, and a first side and a second side vertically connected between the upper surface and the lower surface, the lower surface being opposite to the image sensor The upper surface is away from the image sensor relative to the lower surface, the camera module further includes a first wire, a second wire, and a plurality of flexible supports, and the first side and the second side are respectively fixed The first wire and the second wire are respectively disposed opposite to the first magnet and the second magnet and are fixed to the image sensor, and the first wire and the second wire are respectively connected to the lens module. The optical axes are parallel, and the magnetic directions of the first magnet and the second magnet are respectively directed to the first wire and the second wire at an angle of 60 to 150 degrees, and the lens module is supported by the plurality of flexible supports On the circuit board, the processor is based on The offset controls the current in the first wire and the second wire to cause the lens module to translate in a direction perpendicular to the optical axis of the lens module due to the urging force of the first magnet and the second magnet, thereby The image taken by the lens module during the shooting time is always in the same position of the image sensor. The camera module of claim 1, wherein the magnetic fields of the first magnet and the second magnet are perpendicular to each other, and the first side and the second side of the lens module are perpendicular to each other. The camera module of claim 1, wherein the number of the flexible supports is four. The camera module of claim 3, wherein the lens module includes a third side parallel to the first side, and a fourth side parallel to the second side, the third side and the fourth side Vertically, one of the four flexible supports is respectively connected to the first side, the second side, and the first The intersection of the three sides and the fourth side is connected. The camera module of claim 1, wherein the first wire and the second wire are straight wires. A camera module includes a circuit board, an image sensor disposed on the circuit board, a processor, and a displacement sensor for sensing an offset of the image sensor relative to an object to be photographed, and relative image sensing The lens module has a ring upper surface and a lower surface, and a side surface connected between the upper surface and the lower surface, the lower surface is opposite to the image sensor: the camera module further includes a first wire, a second wire, a third wire, a fourth wire, and a plurality of flexible supports, wherein the first magnet, the second magnet, the third magnet, and the fourth are disposed at an interval of 90 degrees in a circumferential direction of the side surface a first wire, a second wire, a third wire, and a fourth wire are respectively disposed opposite to the first magnet, the second magnet, the third magnet, and the fourth magnet, and are fixed to the image sensor, the plurality of a wire, a second wire, a third wire and a fourth wire are parallel to the optical axis of the lens module, the first magnet and the second magnet are perpendicular to the magnetic field direction and respectively directed to the first wire and the second wire, the third Magnet and fourth magnet The magnetic field is perpendicular to the third wire and the fourth wire, and the lens module is supported on the circuit board by the plurality of flexible supports, and the processor controls the first wire and the second according to the offset The current in the wire, the third wire and the fourth wire causes the lens module to be subjected to the ampere force of the first magnet, the second magnet, the third magnet and the fourth magnet in a direction perpendicular to the optical axis of the lens module Move up so that the subject being photographed through the lens module during the shooting time is always in the same position of the image sensor. The camera module of claim 6, wherein the number of the flexible supports is three, and the three flexible supports are fixed to the lower surface at an interval of 120 degrees in the circumferential direction. The camera module of claim 6, wherein the side surface of the lens module is cylindrical, and the first magnet, the second magnet, the third magnet, and the fourth magnet are curved to match the side surface. magnet. The camera module of claim 8, wherein the first wire, the second wire, the third wire and the fourth wire are arranged in a curved shape on the outer side of the corresponding curved magnet. wire.