KR102106650B1 - Camera Module - Google Patents

Abstract

A camera module according to an embodiment of the present invention includes a lens; A lens mounting stage for supporting the lens in the air; An actuator installed in an outer housing and having first and second driving units for supplying power using electrostatic force for movement of the lens mounting stage and first and second hinges disposed at positions facing the driving units; An input / output terminal supplying power and control signals to the driving units; And a control unit for applying AC power to the input / output terminal.

Description

Camera module

The present invention relates to a camera module.

2. Description of the Related Art In recent years, demands for a small camera module are increasing for various multimedia fields such as tablet computers, camera phones, PDAs, smart phones, and toys, and also for image input devices such as surveillance cameras or video tape recorder information terminals. In particular, smart phones are in a trend of developing small-sized camera modules according to an increase in demand from consumers who prefer a compact design.

Such a camera module is manufactured using an image sensor chip of CCD or CMOS, condensing an object through a lens on the image sensor chip, converting an optical signal into an electrical signal, and displaying the object on a display medium such as an LCD display device. So that the video is delivered.

The camera module as described above includes a plurality of lenses, and an optical focal length is adjusted by changing a relative distance by moving each lens by installing a driving source.

The camera module for ultra-small size and low power consumption is difficult to apply technologies such as VCM used in the existing general camera module, and research related to this has been actively conducted.

An object of the present invention is to provide a camera module that can improve the autofocusing performance by improving the structure of an actuator constituting the autofocusing unit.

A camera module according to an embodiment of the present invention includes a lens; A lens mounting stage for supporting the lens in the air; An actuator installed in an outer housing and having first and second driving units for supplying power using electrostatic force for movement of the lens mounting stage and first and second hinges disposed at positions facing the driving units; An input / output terminal supplying power and control signals to the driving unit; And a control unit for applying AC power to the input / output terminal.

It is preferable that the first and second hinges have a lens fixing part that is disposed so that the lens is tilted around an initial state when a zero voltage is applied and the first and second driving parts are in an initial state.

Preferably, the lens is auto-focused by tilting the lens by applying a positive (+) or negative (-) voltage to the first and second driving units.

It is preferable that the comb teeth of the first driving unit are formed to be movable when the positive (+) pole power is applied, and the comb teeth of the second driving unit are formed to be movable when the negative (-) polar power is applied. .

Alternatively, the comb teeth of the first driving unit may be formed to move when negative (-) pole power is applied, and the comb teeth of the second driving unit may be formed to move when positive (+) pole power is applied. It is possible.

The control unit may further include a detection and rectifying unit that detects and rectifies the AC power applied to the input / output terminal.

Preferably, the input / output terminal is connected to the detection rectifying unit.

In addition, the input / output terminal preferably includes a VSS input terminal and a ground terminal.

Since the present invention can control the tilting operation of the lens using a pair of driving units, it is possible to construct an ultra-thin auto focusing unit at a lower price.

1 is a view schematically showing first and second actuators of an actuator according to an exemplary embodiment of the present invention;
2 is a graph showing AC power input to an actuator according to an exemplary embodiment of the present invention,
3 and 4 is a graph showing a control signal applied to the comb teeth arranged in polarity as shown in FIG. 2 by detecting and rectifying the AC power of FIG. 3,
5 is a view of the lens disposed in a tilted state in an initial state in which power is not applied,
6 is a view showing a state in which both ends of the lens are spaced in parallel by a separation signal applied to the first comb; and
7 is a view showing a state in which the first comb moves further from the position of FIG. 6 so that the lens is tilted in the opposite direction.

Hereinafter, preferred embodiments of the present invention will be described with reference to the drawings.

1 is a view schematically showing first and second driving units of an actuator according to an exemplary embodiment of the present invention, and FIG. 2 is a graph showing AC power input to an actuator according to an exemplary embodiment of the present invention, 3 and 4 is a graph showing a control signal applied to the comb teeth arranged in polarity as shown in FIG. 2 by detecting and rectifying the AC power of FIG. 3, and FIG. 5 is a lens in an initial state in which power is not applied. Drawing in an inclined state, FIG. 6 is a view showing a state in which both ends of the lens are spaced in parallel by applying a separation signal to the first comb, and FIG. 7 is further moved from the position of FIG. 6 to the first comb This is a view showing a state in which the lens is tilted in the opposite direction.

 The actuator according to an embodiment includes four hinges in the form of a one-dimensional cantilever beam supporting the lens support structure so as to be able to float in the air and a lens mounting stage floating in the air in the Z-axis direction. ).

Two of them have an 'S'-shaped support spring that elastically supports the entire stage, and also provides freedom in the Z-axis direction when the lens support structure moves up and down, maintaining the connection between the outer housings. A hinge unit is provided at each connection.

The camera module according to the present invention includes a lens 10 (see FIG. 5), a lens mounting stage, an actuator, a hinge unit, a support spring, an input / output terminal and a control unit.

The lens 10 is installed to adjust the size of an image formed on an image sensor, such as a CCD or CMOS, which is not installed in the camera module. To this end, the lens 10 is installed in a structure movable in the Z-axis direction to adjust the focus. do. The lens 10 uses an electrostatic force of a driving unit to be described later as a driving source, and an optical focal length is adjusted.

The lens mounting stage supports the lens 10 in a state of being floating in the air, so that it is close and spaced apart from the image sensor not shown. To this end, the lens mounting stage is connected to a plurality of hinge units and a motion control hinge, so that movement is controlled according to a control signal of a controller not shown.

It is preferable that the actuator is provided with an electrostatic driving unit. In addition, the actuator may have four or more electrostatic drive units. The driving unit is composed of a stator, a mover, and a drive, and can be operated in a constant voltage method. That is, when power is applied, a potential difference is generated between the stator and the mover, and electrostatic attraction is generated due to the potential difference. Then, each of the driving units 31a and 31b is pulled to each other, and the lens mounting stage can be pulled. As described above, when the lens mounting stage is pulled, the lens 10 may move upward, so that the lens movement section has a maximum stroke.

An embodiment of the present invention is characterized in that the actuator is divided into first and second driving units 30a and 30b and first and second hinges 30c and 30d, which are electrically divided from each other. . Accordingly, the first and second driving units 30a and 30b receive control signals through input / output terminals and move, and the first and second hinges 30c and 30d are the first and second driving units 30a ( 30b) may be a rotation center of the tilted lens 10 according to the movement. This structure and operation will be described in more detail later.

It is preferable that the hinge unit connects the lens mounting stage and the mover with a motion control hinge. The hinge unit is provided in a cantilever shape, the lens mounting stage is connected to the free end side, and a motion control hinge is connected to the fixed end side. Therefore, the lens mounting stage can move freely around the motion control hinge. Meanwhile, the hinge unit may also serve to interconnect the stator and the mover. At this time, it is preferable that this connection portion is also connected to a controllable motion control hinge. On the other hand, the motion control hinge is to control the movement of the hinge according to the control signal of the controller (not shown), according to the motion of the motion control hinge, the position of the hinge unit can be controlled.

A support spring is installed on the lower portion of the hinge unit to elastically support the hinge unit in the Z-axis direction.

The input / output terminals are electrically connected to the frame 1 forming the outer appearance of the actuator, and as shown in FIG. 1, it is preferable that each of the two is provided in a pair. At this time, the input / output terminal may be provided with a VSS input terminal and a ground terminal.

The control unit may include a detection and rectification unit 110, and the input / output terminal may be connected to the detection and rectification unit 110. The detection and rectifying unit 110 may control the polarity and size of the power output to the input / output terminal.

The actuator according to an exemplary embodiment of the present invention is composed of a total of two first and second driving units 30a and 30b, as shown in FIG. 1, and the first and second driving units 30a and 30b ) Can be controlled by being connected to input / output terminals. For example, if the comb 31a of the first driving unit 30a is set to move at the positive (+) pole, the comb 31b of the second driving unit 30b moves at the negative (-) pole It is good to set this. In this case, as illustrated in FIGS. 2 to 4, when AC power is detected and rectified by the control unit, the comb teeth 31a of the first driving unit 30a are rectified as illustrated in FIG. 3. It is moved only by the positive (+) pole power supply, and the comb teeth 31b of the second driving unit 30b can be moved only by the rectified negative (-) power supply as shown in FIG. 4. Accordingly, when AC power is input to the first and second driving units 30a and 30b, the first and second driving units (in accordance with the power size of the positive (+) pole and the power of the negative (-) pole, 30a) (30b) can be moved respectively.

Meanwhile, the size of the power of the positive (+) pole and the size of the negative (-) pole of the AC power may be the same or may have different values. If the power values of the positive and negative poles and the power of the negative and negative poles are formed at the same value, the first and second driving units 30a and 30b move by the same distance, but their sizes are formed differently. When the first and second driving units 30a and 30b are moved by different distances. That is, the size of the positive (+) pole and the negative (-) pole of the rectified AC power output from the control unit can be adjusted to change over time. For example, the size of the positive (+) pole is 10 ㎶. Then, when the negative (-) pole is formed to have a size of -5 mm 2, the elevation height of the second driving unit 30b can be controlled to be lower than that of the first driving unit 30a. In the same way, it is also possible to control the elevation height of the first driving unit 30a to be lower than the elevation height of the second driving unit 30b.

According to the above-described configuration, in order to control a total of two second and second driving units 30a and 30b, even if an input / output terminal is not provided for each of the first and second driving units 30a and 30b, the control unit Two driving units may be controlled according to the switching of the positive (+) and negative (-) poles of the output AC power.

Meanwhile, first and second hinges 30c and 30d are installed at positions facing the first and second driving parts 30a and 30b, and the first and second hinges 30c and 30d are provided. It is preferable that the lens fixing portion 31c is provided.

5 to 7 are views showing an example of the operation of the actuator according to the power control described above, a view showing a first driving unit (30a) and the first hinge (30c) facing each other.

As shown in FIG. 5, when 0 V of power is applied through the input / output terminal, the first driving unit 30a maintains an initial position. At this time, the lens 10 is the first, as shown. It may be arranged in an inclined state with respect to the lens fixing portion 31c provided on the hinge 30c. At this time, in the lens 10, the lens fixing part 31c may be a rotation center, and the height of the lens fixing part 31c may be kept constant.

On the other hand, when power is applied for control, the first driving unit 30a tilts the lens 10, as shown in FIG. 6, to the lens fixing unit 31c where the lens 10 is fixed. The lens 10 can be moved to be parallel. At this time, if the focus is correct, the movement may be stopped, but if the focus is not correct, the first and second driving units 30a and 30b are gradually moved based on the position of FIG. 6 to the position of focus. The lens 10 can be tilted.

For example, when the focus image in the corner is collapsed, the lens 10 may be tilted in a predetermined direction around the lens fixing part 31c by moving the first driving part 30a as shown in FIGS. 5 and 7. By making it possible, it is possible to place and fix the lens 10 at a position where an accurate image is formed.

On the other hand, although not shown, the position and focus of the lens 10 while moving in the same manner as the first driving unit 30a and the first hinge 30c, the second driving unit 30b and the second hinge 30d are also Can be adjusted.

In particular, in the past, a total of four driving units were formed, and in order to perform individual control, it was difficult to implement separate input / output terminals, but according to the present invention, the number of driving units was reduced to two, and for control Since the terminals also need to constitute a pair of input / output terminals connected to the two driving units at the same time, the structure of the actuator can be easily constructed as compared to the prior art. In addition, since only two driving units need to be configured, manufacturing cost is reduced, and it is possible to provide an actuator having a simpler structure.

The embodiments of the present invention described above and illustrated in the drawings should not be construed as limiting the technical spirit of the present invention. The scope of protection of the present invention is limited only by the matters described in the claims, and a person having ordinary knowledge in the technical field of the present invention can improve and modify the technical spirit of the present invention in various forms. Therefore, such improvements and modifications will fall within the protection scope of the present invention as long as it is apparent to those skilled in the art.

10; Lens 30a; First drive
30b; A second driver 30c; 1st hinge
30d; 2nd hinge

Claims (8)

lens;
A lens mounting stage for supporting the lens in the air;
It is installed in the outer housing, and the first driving unit and the second driving unit supplying power for movement of the lens mounting stage using electrostatic force, and the first driving unit and the first driving unit disposed at opposite positions with the lens interposed therebetween An actuator including a hinge and a second hinge disposed at a position facing the lens with respect to the second driving unit;
An input / output terminal supplying power and control signals to the first driving part and the second driving part; And
Includes a control unit for applying an AC power to the input and output terminals;
The first driving part and the first hinge are paired to adjust the tilting of the lens in the first axis direction,
The second driving unit and the second hinge are paired to control the tilting of the lens in the second axis direction.
The method of claim 1, wherein the first hinge and the second hinge,
A camera module including a lens fixing unit that is arranged to tilt the lens around the first hinge or the second hinge when a zero voltage is applied and the first and second driving units are in an initial state.
According to claim 1,
The first driving part and the second driving part move as a positive (+) or negative (-) voltage is applied,
The lens is tilted according to at least one movement of the first driving part and the second driving part,
Autofocusing is performed according to the tilting of the lens, the camera module. delete delete delete delete delete

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