KR100636649B1 - Small camera device for auto focus - Google Patents

Abstract

The present invention relates to a compact camera apparatus having an autofocus function for miniaturizing the size of a camera apparatus and performing autofocusing more precisely by moving a lens module group with a driving force generated between a coil to which a power is applied and a magnet.

In order to implement such a compact camera device, a lens module group set at a predetermined magnification on an optical axis formed by an image sensor is coupled to adjust a focal length to a barrel on which a magnet is fixed, and is controlled from a controller according to a series of current excitation methods. The magnet rotates under the influence of the magnetic field generated by the applied current, and the rotational force generated in the fixed barrel drives the lens module group on the optical axis formed by the image sensor and the subject due to a mechanical device that converts the linear motion.

Accordingly, the camera device can be miniaturized to correct the focusing error of the image captured by the image sensor while the lens module group is moved on the optical axis, thereby further improving the sharpness of the captured image.

Telecommunication equipment, camera, focusing

Description

Small camera device with autofocus function {SMALL CAMERA DEVICE FOR AUTO FOCUS}

1 is an exploded perspective view showing a camera device implemented according to an embodiment of the present invention;

2 is a perspective view of the combination of the camera device shown in FIG.

3 is a longitudinal cross-sectional view of the camera apparatus shown in FIG. 2 driven in a remote mode;

4 is a schematic partial perspective view of the driving unit shown in FIG. 3;

5 is a longitudinal cross-sectional view of a state in which the camera apparatus shown in FIG. 2 is driven in a near mode;

FIG. 6 is a schematic partial perspective view of the driving unit shown in FIG. 5.

<Description of Symbols for Main Parts of Drawings>

100: first outer housing 102: magnetic material

104: first yoke 110: second outer housing

112: magnetic material 114: third yoke

116: magnetic material 120: second yoke

122: magnetic body 124: magnetic body

130: fourth yoke 132: magnetic material

200: image sensor 300: lens module group

310: first coupling portion 400: first barrel

410: removable groove 420: second coupling portion

430: hollow 500: magnet

600: second barrel 610: fixing groove

620: main part 630: coupling hole

700 Bobbin 710

720: coupling hole 800: the first coil

810: second coil 900: control unit

910: second flexible PCB 920: first flexible PCB

The present invention relates to a small camera device having an autofocus function. In particular, a small camera having an autofocus function capable of capturing an image of a subject more clearly by installing a camera having a precise autofocusing function in a small information communication device such as a mobile phone. It relates to a camera device.
In recent years, as mobile phones equipped with small cameras have become more common, users can conveniently capture images of a subject without having a digital camera, so that users own a mobile phone equipped with a small camera comparable to that of a digital camera. Was done.
However, in order to implement the performance of the existing digital camera, a small camera for a portable terminal has technical limitations.
In order to improve the quality of the image captured by capturing the image of the subject, the focal length between the lens module where the image of the subject is projected and the point where the image is captured must be exactly matched. Since all the subjects cannot be imaged with clear image quality, the point where the image is captured and the focal length formed by the lens module should be flexible.
However, the conventional general camera or digital camera adopts a camera device of a method of driving the barrel in which the lens module is coupled with complicated gears, so that its volume is large and its length in the optical axis direction becomes long.
Such a method is not suitable to be applied to a small information communication device as it is, and despite the deterioration in the quality of the captured image, the lens module is fixed and a focal length is applied.
However, when the lens module is fixed, the lens module is initially focused when shooting a certain distance of the subject set, but when shooting a different distance of the subject is not in focus due to the problem that the quality of the recorded image is deteriorated. .

Accordingly, an object of the present invention is to solve the above problems, by combining a camera in which a lens module flows in a small information communication device, the lens module is changed in accordance with the focusing error of the captured image while changing the focal length The present invention provides a compact camera device having an autofocus function having an autofocusing function.

Technical means of the present invention for achieving the above object, the image sensor is fixed to the outer housing, arranged on the optical axis formed by the image sensor, the lens module group consisting of a plurality of lenses, the lens module group is combined The first barrel, and coupled to the first barrel in a threaded manner when the first barrel is rotated to raise and lower the first barrel in the optical axis direction, by rotating the second barrel, the first barrel fixed to the outer housing, And a controller configured to move on the optical axis and a controller configured to correct the detected focusing error by driving the driver when a focusing error of an image captured by the image sensor is detected.
The lens module group is characterized in that coupled to the first barrel to be fixed by screwing in order to set the optimum initial position.
The driving unit is fixed to the circumference of the first barrel and the radially polarized magnet, a first coil wound around the optical axis from the outside of the magnet is fixed to one side of the second barrel, the magnet and A first magnetic body group having the same shape between the first coils and arranged at regular intervals, a bobbin arranged on the optical axis and fixed to the external housing, and wound around the bobbin with the same size as the first coil, And a second coil disposed together with the first coil on the outside of the magnet, and having the same shape as the first magnetic group between the magnet and the second coil to form a predetermined mechanical angle with the first magnetic group. It is characterized by including 2 magnetic body groups.
The first magnetic body group has a first yoke that is magnetized to one polarity of the magnetic field generated by the first coil to transmit magnetic flux to an upper end of the first magnetic body group, and a different polarity of the magnetic field generated by the first coil. And a second yoke which is magnetized to transmit magnetic flux to the lower end of the first magnetic body group.
The second magnetic body group is magnetized to one polarity of the magnetic field generated by the second coil, and to a third yoke for transmitting magnetic flux to the lower end of the second magnetic body group, and to another polarity of the magnetic field generated by the second coil. And further include a fourth yoke for transmitting magnetic flux to an upper end of the second magnetic body group.
The external housing forms a side of the first magnetic body group, forms a predetermined mechanical angle with the first external housing to rotate the first external housing and the magnet to which the second yoke is coupled, and the second magnetic body group. Forming one side of the second yoke is characterized in that consisting of the second outer housing coupled.
The driving unit may further include a first flexible PCB for applying power to the image sensor and a second flexible PCB for supplying driving power controlled by the controller to the first coil and the second coil. do.
The second barrel may include a recess for coupling the first coil to one side of an outer circumferential surface and a coupling hole for coupling a magnetic body of the first yoke to an inner side of the recess.
The bobbin is characterized in that it comprises a recess for coupling the second coil to one side of the outer peripheral surface and the coupling hole for coupling the magnetic material of the third yoke to the inner side of the recess.
The magnet may be formed in a cylindrical shape while repeating the N pole and the S pole in proportion to the number of magnetic bodies formed by the first magnetic body group or the second magnetic body group.
Hereinafter, with reference to the accompanying drawings, a preferred embodiment of a camera device for information communication apparatus according to the present invention will be described in detail.
1 is an exploded perspective view of a camera apparatus according to an embodiment of the present invention, Figure 2 is a combined perspective view of FIG.
As shown, the compact camera device of the present embodiment is arranged on an optical axis formed by the image sensor 200 and the image sensor 200 fixed to the external housings 100 and 110 and comprises a plurality of lenses 320. The first barrel 400 to which the module group 300 and the lens module group 300 are coupled, the second barrel 600 fixed to the outer housings 100 and 110 by being coupled to the first barrel 400 by a screw method. When the focusing error of the image captured by the driver and the image sensor 200 is rotated by rotating the first barrel 400, the current is applied to the driver by a predetermined excitation method to correct the detected focusing error. A control unit 900 is included.
The compact camera apparatus of the present invention having such a configuration changes the magnetic field by controlling a current applied to the driving unit to implement an autofocusing function for improving the image quality of the image captured by the image sensor 200. Torque is generated in the first barrel 400 coupled to the lens module group 300 is precisely moved in the optical axis direction.
The outer housings 100 and 110 are preferably made of a first outer housing 100 and a second outer housing 110 which are made of a material that is easy to magnetize to form a frame of a camera device.
The lens module group 300 is composed of a plurality of lenses 320 and is set at a constant magnification. The first coupling portion 310 of the lens module group 300 has a threaded groove formed therein, so that the first barrel 400 is formed. It is configured to be inserted into and fixed by rotating the hollow portion 430).
The first barrel 400 has a screw groove of the hollow part 430 designed to be integrally coupled with the first coupling part 310 of the lens module group 300, and a magnet 500 to which the magnet 500 is attached and fixed. The coupling part 420 includes a detachable groove 410 that flows and guides on the optical axis due to the torque generated while the magnet 500 rotates.
The detachable groove 410 is a mechanical device in which a groove is formed on the outer circumferential surface of the first barrel 400 in a screw shape in order to convert the rotational force of the first barrel 400 into a linear motion.
The second barrel 600 is fixed to the first outer housing 100 is located on one side of the hollow portion 430 is fixed groove 610 to engage with the removable groove 410, the first coil 800 is wound Or a coupling hole 630 for coupling the recessed portion 620 and the magnetic body 102 magnetized to the first yoke 104 of the first outer housing 100.
The fixing groove 610 is formed in a threaded form and engages with the removable groove 410 of the first barrel 400 to not only flow guide the linear movement on the optical axis line due to the torque of the first barrel 400, but also the first barrel. It serves to support 400 does not leave the optical axis arrangement.
In addition, the driving unit is fixed to the circumference of the first barrel 100, the radially polarized magnet 500, the outer side of the magnet 500 is wound around the optical axis line to one side of the second barrel 600 The first magnetic group is fixed to each other, the first magnet group 800, the magnet 500 and the first coil 800 are arranged at a predetermined interval, the same shape, respectively arranged on the optical axis line to the second outer housing 110 The second coil 810, which is fixed to the bobbin 700 and the bobbin 700, is wound around the same size as the first coil 800 and is disposed together with the first coil 800 on the outside of the magnet 500, A second magnetic body group is formed between the magnet 500 and the second coil 810 in the same shape as the first magnetic body group to form a predetermined mechanical angle with the first magnetic body group.
The magnet 500 of the present invention has a cylindrical shape while the N pole and the S pole are repeated in proportion to the number of magnetic bodies formed by the first magnetic body group or the second magnetic body group, and the first magnetic body group and the second magnetic body group are respectively. As the magnetized and changed magnetic flux rotates around the optical axis.
The first magnetic body group is a magnetic field generated by the first coil 800 and is magnetized to one polarity of the magnetic field while being located at one side of the first external housing 100 so that the first magnetic body group is magnetized to the upper end of the first magnetic body group. The second yoke 120 further magnetizes to the other polarity of the magnetic field generated by the first yoke 104 and the first coil 800 to transmit the magnetic flux, and transmits the magnetic flux to the lower end of the first magnetic body group.
Due to the first coil 800 wound so that the polarity is arranged in the optical axis direction, when the power is applied, the first yoke 104 is magnetized to the N pole and the second yoke 120 is magnetized to the S pole. Similarly, when the direction of the current applied to the first coil 800 is changed, the first yoke 104 is magnetized to the S pole and the second yoke 120 is magnetized to the N pole, so that the respective yokes 104 and 120 Magnetized magnets 102 and 122 are magnetized.
The bobbin 700 may include a coupling hole 720 for coupling the magnetic body 112 magnetized to the third yoke 114 of the second outer housing 110, and a recess in which the second coil 810 is wound and coupled ( 710, the hollow portion of the bobbin 700 is coupled to form a pair with the shape of the image sensor 200. Since the image sensor 200 of the present embodiment has a rectangular shape, the hollow portion of the bobbin 700 coupled thereto has a rectangular shape.
In addition, the second magnetic body group is magnetized to one polarity of the magnetic field while being located at one side of the second external housing 110 to be magnetized by the magnetic field generated by the second coil 810, thereby applying magnetic flux to the lower end of the second magnetic body group. The electronic device further includes a fourth yoke 130 that is magnetized to different polarities of the magnetic field generated by the third yoke 114 and the second coil 810 to transmit the magnetic flux to the upper end of the second magnetic body group.
Similarly, when power is applied in the same direction as the first coil 800 to the second coil 810 wound so that the polarity is arranged in the optical axis direction, the third yoke 114 is magnetized to the S pole and the fourth yoke 130 Is magnetized to the N pole to magnetize each of the magnetic bodies 112 disposed at the lower end of the second magnetic body group to the S pole and to magnetize each of the magnetic bodies 132 disposed at the upper end of the second magnetic body group to the N pole.
When the direction of the current applied to the two coils 810 is changed, the direction of the magnetic force line is also changed so that the third yoke 114 is magnetized to the N pole and the fourth yoke 130 is magnetized to the S pole, and each of the yokes 114 and 130. Magnetized together into respective magnetic bodies 112 and 132 magnetized to.
As shown, a magnetic body having five magnetic bodies 102 magnetized to the first yoke 104 and a second yoke 120 magnetized to the five magnetic bodies 122 are located on the first yoke 104. Constantly spaced between 102 is fixed to one side of the first outer housing (100).
In addition, five magnetic bodies 112 are magnetized to the third yoke 114, and a fourth yoke 130 in which the five magnetic bodies 132 are magnetized is disposed between the magnetic bodies 112 on the third yoke 114. Constantly spaced and fixed to one side of the second outer housing (110).
Five magnetic bodies 102 on the first yoke 104 are magnetic fields formed by the first coil 800 to be applied according to the excitation method of the current applied to the first coil 800 or the second coil 810. Is magnetized to one polarity, the five magnetic bodies 122 on the second yoke 120 are magnetized to the other polarity, and the second coil 810 sequentially powered also forms a magnetic field to form the third yoke 114. The five magnetic bodies on the magnetization with one polarity and the five magnetic bodies 132 on the fourth yoke 130 are magnetized with the other polarity, so that the magnet 500 consisting of ten poles in the cylindrical shape is formed by the magnetic bodies 102, 112, 122, and 132. It is configured to generate a rotational force by the attraction and repulsive force by the magnetic field.
In addition, by arranging a predetermined mechanical angle between the first magnetic body group and the second magnetic body group in order to generate a smooth torque in the magnet 500, a current according to a constant excitation method is applied to the first coil 800 to the first After the magnetic body is magnetized and the magnet 500 rotates under the influence of the changed magnetic flux, a constant excitation current is similarly applied to the second coil 810 to form the first magnetic body while the second magnetic body is magnetized. The magnet 500 is installed to be rotatable by the machine angle.
Here, when the first magnetic body group and the second magnetic body group are arranged in the same line without forming a constant mechanical angle, the current applied to the first coil 800 and the second coil 810 according to a predetermined current excitation method is Since the magnet 500 does not rotate even if it changes, the first magnetic body group and the second magnetic body group are fixed at a predetermined mechanical angle.
It is apparent from the viewpoint of those skilled in the art that the number of magnetic bodies and the corresponding number of magnets 500 can be more precisely rotated so as to improve the function of autofocusing, which is not limited to the above embodiments.
In addition, the driving unit includes a first flexible PC 920 for supplying power to the image sensor 200 from the controller 900 and transmitting information about the captured image image, and the image transmitted to the controller 900. When it is detected that there is a focusing error in the image, it is preferable to further include a second flexible PCB 910 for supplying driving power according to the current excitation method set in the first coil 800 and the second coil 810. .
The controller 900 includes a keypad (not shown) including an on / off button for driving the image sensor 200 and a shooting button, and according to the set current excitation method, the first coil 800 or the second coil 810. By applying a current to the), the polarity of the magnetic body (102, 112, 122, 132) is changed to control the driving of the magnet 500.
When the control unit 900 detects that there is a focusing error in the image captured by the image sensor 200, the magnet 500 is fixed by switching and controlling a current sent to the first coil 800 or the second coil 810. By driving the first barrel 400, the focal length between the lens module group 300 and the image sensor 200 coupled to the first barrel 400 is adjusted to achieve a clear image quality.
Hereinafter, the operation of the camera device having the above configuration will be described.
FIG. 3 is a cross-sectional view illustrating focusing with the camera apparatus of the present embodiment in a remote mode, and FIG. 4 is a conceptual view illustrating a principle of driving the camera apparatus to execute the focusing of FIG. 3.
FIG. 3 illustrates a combination of the lens module group 300 combined with the influence of a magnetic field generated by a current applied from the controller 900 to correct a focusing error caused by an out of focus of an image captured by the image sensor 200. 1 is a case in which the barrel 400 is driven in the direction in which the image sensor 200 is located.
FIG. 4 is a view illustrating the driving principle in more detail as shown in FIG. 3. The excitation method of the current applied to the first coil 800 and the second coil 810 according to the present embodiment is illustrated in FIG. Although various, for convenience of explanation, the one-phase excitation method will be described.
Referring to the drawing, when a current is applied to the first coil 800 in the counterclockwise direction, the upper end of the first coil 800 in the direction in which the lens module group 300 is disposed becomes the N pole and the first coil ( The lower end of the 800 is a magnetic field of the S pole. Due to this magnetic field, the first yoke 104 is magnetized to the N pole, and the magnetic body 102 magnetized to the first yoke 104 is also magnetized to the N pole, and the second yoke 120 is magnetized to the S pole to form the second pole. The magnetic body 122 magnetized to the yoke 120 is magnetized to the S pole.
The magnet 500 is rotated due to the attractive force and repulsive force generated between the magnetic field generated by the magnetized magnetic bodies 102 and 122, respectively, as the magnetic field of the magnet 500, which acts as a rotor. Since the magnetic velocities of the magnetic bodies 102 and 122 are the same, the magnet 500 rotates under the influence of the closest magnetic body.
For example, the magnet 500 rotated due to the magnetic body 102 of the first yoke 104 that is N-polar in FIG. 4 is similarly illustrated by the influence of the current applied to the second coil 810 in the counterclockwise direction. As described above, the magnetic bodies 112 and 132 magnetized to the third yoke 114 and the fourth yoke 130 are magnetized and at the same time, the magnetic bodies 132 of the fourth yoke 130 having the N polarity having a large magnetic flux strength. It moves to the position where is.
In the magnet 500 moved to the above position, the magnetic body 102 of the first yoke 104 is the S pole and the magnetic body of the second yoke 120 due to the current applied clockwise to the first coil 800. 124 is magnetized to the north pole, and is rotated again to the position where the magnetic body 124 of the second yoke 120 is located.
As a result of the mechanical device for circulating and generating torque in the magnet 500 and converting the rotational force into linear motion, the first barrel 400 to which the magnet 500 is fixed is driven toward the image sensor 200.
FIG. 5 is a cross-sectional view showing focusing performed in a near mode with the camera apparatus of the present embodiment, and FIG. 6 is a conceptual diagram illustrating a principle of driving the camera apparatus to execute the focusing of FIG. 5.
FIG. 5 illustrates an embodiment in which the lens module group 300 is combined due to the influence of a magnetic field generated by a current applied from the controller 900 to correct a focusing error caused by an out of focus of an image captured by the image sensor 200. 1 is a case in which the barrel 400 is driven in a direction toward the subject.
In addition, FIG. 6 operates in the same manner as described with reference to the drawing illustrated in FIG. 4. In this case, when the current is applied to each coil in the reverse order, the magnet 500 rotates in the clockwise direction opposite to that of the subject. The first barrel 400 is driven in the direction.
In this manner, the first barrel 400 on which the lens module group 300 is mounted flows and corrects a focusing error of an image captured by the image sensor 200, and the focused image is stored in memory (not shown). It is stored in or output to an output means such as a display screen (not shown).
Then, by manually rotating the lens module group 300 coupled to the screw groove (not shown) formed in the hollow portion 430 of the first barrel 400, between the image sensor 200 and the lens module group 300 The focal length can be arbitrarily adjusted to compensate for the limitation of the driving width that can be driven by autofocusing.
While specific embodiments of the present invention have been described and illustrated above, it will be apparent that the present invention may be embodied in various modifications by those skilled in the art. Such modified embodiments should not be understood individually from the technical spirit or the prospect of the present invention, but should fall within the claims appended to the present invention.

Accordingly, in the present invention, by combining a camera in which a lens module group flows with a small information communication device, a small camera apparatus in which autofocusing is performed by changing the focal length while the lens module group moves in accordance with a focusing error of an image to be captured To provide.

Claims (10)

An image sensor fixed to the outer housing; A lens module group arranged on an optical axis formed by the image sensor and comprising a plurality of lenses; A first barrel to which the lens module group is coupled; A second barrel coupled to the first barrel in a screwing manner to lift and lower the first barrel in the optical axis direction when the first barrel is rotated, the second barrel being fixed to the outer housing; A driving unit for rotating the first barrel to flow on the optical axis; And And a controller configured to correct the detected focusing error by driving the driving unit when a focusing error of the image captured by the image sensor is detected. The driving unit, A magnet fixed to the circumference of the first barrel and radially divided in the radial direction; A first coil wound around the optical axis outside the magnet and fixed to one side of the second barrel; A first magnetic body group having the same shape between the magnet and the first coil and disposed at regular intervals; A bobbin arranged on the optical axis and fixed to the outer housing; A second coil wound around the bobbin and having the same size as the first coil, and disposed together with the first coil on an outer side of the magnet; And And a second magnetic body having the same shape as the first magnetic body between the magnet and the second coil to form a predetermined mechanical angle with the first magnetic body. Camera device. The method of claim 1, wherein the lens module group, Small camera apparatus having an autofocus function, characterized in that coupled to the first barrel by a screw fastening method to set the optimum initial position. delete The method according to claim 1, wherein the first magnetic body group, A first yoke that is magnetized to one polarity of the magnetic field generated by the first coil to transmit magnetic flux to an upper end of the first magnetic body group; And And a second yoke which is magnetized to different polarities of the magnetic field generated by the first coil and transmits magnetic flux to the lower end of the first magnetic body group. The method of claim 1, wherein the second magnetic body group, A third yoke that is magnetized to one polarity of the magnetic field generated by the second coil to transfer magnetic flux to a lower end of the second magnetic body group; And  And a fourth yoke which is magnetized to another polarity of the magnetic field generated by the second coil to transfer the magnetic flux to the upper end of the second magnetic body group. The method of claim 4 or 5, wherein the outer housing, A first outer housing forming one side of the first magnetic body group and the second yoke coupled thereto; And A second external housing which forms a predetermined mechanical angle with the first external housing to rotate the magnet, forms a side of the second magnetic body group, and the fourth yoke is coupled; Compact camera unit with. The method of claim 1, wherein the driving unit, A first flexible PC for applying power to the image sensor; And And a second flexible PCB for supplying the driving power controlled by the control unit to the first coil and the second coil. The method according to claim 4, wherein the second barrel, A main portion to which the first coil is coupled to one side of an outer circumferential surface; And a coupling hole for coupling the magnetic material of the first yoke to the inner side of the recessed portion. The method according to claim 5, The bobbin, A main portion to which the second coil is coupled to one side of an outer circumferential surface; And a coupling hole for coupling the magnetic body of the third yoke to the inner side of the recessed portion. The method according to claim 1, wherein the magnet, The compact camera device having an autofocus function, characterized in that the cylindrical shape while repeating the N pole and the S pole in proportion to the number of the magnetic material formed by the first magnetic group or the second magnetic group.

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