KR20120032352A - Camera module - Google Patents

Abstract

PURPOSE: A camera module is provided to attach an IR(Infrared Ray) filter on the upper side of an image sensor, thereby reducing the size of the noise displayed on an actual screen. CONSTITUTION: A cavity is formed in the lower side of a PCB to accept an image sensor(80). One side of the upper side of the cavity is electrically connected to one side of the upper side of the image sensor. An IR filter(70) is attached to the upper side of the image sensor. A foreign substance(110) falls on the IR filter, a view angle of the foreign substance is reduced. The size of the noise due to the foreign substance displayed on an actual screen is reduced.

Description

Camera module {Camera module}

The present invention relates to a camera module.

Recently, the demand for small camera modules is increasing for various multimedia fields such as notebook personal computers, camera phones, PDAs, smart phones, toys, and image input devices such as surveillance cameras and video terminals of video take recorders. .

As the pixel size of the sensor applied to the camera module is downsized and the height of the module is lowered, management of inflow of foreign matters and securing mechanical reliability of the camera module such as tilt or shift of the lens optical axis The development of mount structures has become a very important topic.

Currently, the biggest influence on the reliability of the camera module is the holder, which mechanically connects the lens barrel and the sensor and protects the sensor from foreign objects and other impacts. In particular, when the lens barrel and the holder are fastened, the reliability is most affected.

Conventionally, a screw coupling method is used to fasten the lens barrel and the holder. When the screw is coupled, a foreign matter (particle) generated by the friction of the screw thread falls to the upper part of the image sensor in the holder, thereby causing a defect due to the foreign matter.

The present invention provides a camera module that can prevent a defect caused by falling foreign matters to the image sensor.

According to an aspect of the present invention, an image sensor comprising a plurality of pixels for sensing image information and a non-imaging area, an image sensor for converting an incident optical image into an electrical signal, and a cavity for accommodating the image sensor Provided is a camera module including a printed circuit board formed at a lower side thereof and having an upper side of the cavity electrically connected to an upper side of the image sensor, and an IR filter attached to the upper side of the image sensor to filter infrared rays.

In an embodiment of the present invention, by attaching the IR filter to the upper surface of the image sensor, foreign matter that has fallen on the conventional image sensor may fall on the IR filter, thereby reducing the size of noise displayed on the actual screen by the foreign matter. For this reason, in the present invention, there is an effect that problems caused by the foreign matter can be improved to good.

1 is a cross-sectional view of a camera module according to an embodiment of the present invention.
2 is a cross-sectional view of a first printed circuit board according to an exemplary embodiment of the present invention.
3 is a diagram illustrating an upper surface of an image sensor in which an IR filter according to an exemplary embodiment of the present invention is disposed.
4 is a cross-sectional view when foreign matter falls to the camera module according to an exemplary embodiment of the present invention.
Figure 5a is an exemplary view of the actual screen according to the foreign matter dropped in the conventional image sensor, Figure 5b is an illustration of the actual screen according to the foreign matter dropped in the IR filter in the present invention.

As the inventive concept allows for various changes and numerous embodiments, particular embodiments will be illustrated in the drawings and described in detail in the written description. However, this is not intended to limit the present invention to specific embodiments, it should be understood to include all modifications, equivalents, and substitutes included in the spirit and scope of the present invention.

Terms including ordinal numbers such as first and second may be used to describe various components, but the components are not limited by the terms. The terms are used only for the purpose of distinguishing one component from another.

For example, without departing from the scope of the present invention, the second component may be referred to as the first component, and similarly, the first component may also be referred to as the second component.

When a component is said to be "connected" or "connected" to another component, it may be directly connected to or connected to that other component, but it may be understood that another component may exist in between. Should be. On the other hand, when a component is said to be "directly connected" or "directly connected" to another component, it should be understood that there is no other component in between.

The terminology used herein is for the purpose of describing particular example embodiments only and is not intended to be limiting of the invention. Singular expressions include plural expressions unless the context clearly indicates otherwise. In the present application, the terms "comprises", "having", and the like are used to specify that a feature, a number, a step, an operation, an element, a component, But do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, or combinations thereof.

Now, a camera module according to an embodiment of the present invention will be described in detail with reference to the drawings. The same or corresponding components are denoted by the same reference numerals regardless of the reference numerals, and redundant description thereof will be omitted.

1 is a cross-sectional view of a camera module according to an embodiment of the present invention, FIG. 2 is a cross-sectional view of a first printed circuit board according to an embodiment of the present invention, and FIG. 3 is an IR filter according to an embodiment of the present invention. 4 is a cross-sectional view of a foreign substance falling on the camera module according to an exemplary embodiment of the present invention, and FIG. 5A is an exemplary view of an actual screen according to a foreign substance falling on a conventional image sensor. 5b is an exemplary view of the actual screen according to the foreign matter dropped to the IR filter in the present invention.

As shown in FIG. 1, the camera module of the present invention includes a case 10, an upper elastic member 20, a lens barrel 30, an actuator 40, a lower elastic member 50, a frame 60, and an IR. The filter 70 includes an image sensor 80, a first printed circuit board 90, and a second printed circuit board 100.

Although the present invention shows a camera module including an actuator 40 which is a movable part for moving the lens barrel 30 along the optical axis direction O for auto focusing, the present invention shows an actuator 40. Applicable to the camera module omitted). In the camera module in which the actuator 40 is omitted, the lens barrel 30 is screwed with the holder instead of the bobbin 41. In the present invention, the bobbin 41 performs the same function as the holder for fixing the lens barrel 30.

The case 10 has a shape of a hexahedron having an open lower portion, and a light transmission hole is formed in an upper center portion. The lower part of the case 10 is supported by the frame 60.

The case 10 is combined with the frame 60 to form a space, and the space includes an upper elastic member 20, a lens barrel 30, and an actuator 40.

The case 10 is preferably made of plastic for insulation between the inside and the outside, and may be injection molded for mass production.

The upper elastic member 20 is inserted into the upper portion of the case 10 as a leaf spring, the outer portion is supported by the yoke 44 of the actuator 40 and the inner portion is in contact with the bobbin 41 of the actuator 40 The upper side of 41 is pressed.

The lower elastic member 50 is positioned below the actuator 40 as a leaf spring to press the lower side of the bobbin 41.

The lower elastic member 50 may be insert injected from the bobbin 41, or may be bonded with a bond.

The lens barrel 30 is a means for fixing and protecting a plurality of lenses. Inside the lens barrel 30, a plurality of lenses capable of entering an optical image of a subject are sequentially stacked along the optical axis direction O. FIG. .

A thread is formed on the circumferential surface of the lens barrel 30, and the thread is screwed with the thread formed on the inner circumferential surface of the bobbin 41.

The bobbin 41 has a cylindrical shape in which the upper and lower portions are open, and a thread corresponding to the thread 31 of the lens barrel 30 is formed on the inner circumferential surface thereof. In the present invention, the lens barrel 30 can be screwed to the inner circumferential surface of the bobbin 41 to match the far focusing of the camera module.

On the peripheral surface of the bobbin 41, a coil 42 interacting with the permanent magnet 43 is wound in a direction perpendicular to the magnetic flux.

Inside the case 10, a yoke 44 is inserted to prevent the magnetic field between the coil 42 and the permanent magnet 43 from leaking to the outside, and the permanent magnets 43 are mutually based on the bobbin 41. It is mounted inside the yoke 44 so as to face each other. Yoke 44 is supported by frame 60.

When a voltage is applied to the coil 42, the current flowing through the coil and the magnetic field of the permanent magnet 43 interact with each other (Fleming's left-hand rule), so that the bobbin 41 is forced upward in the optical axis direction. At this time, as the intensity of the current applied to the coil 42 increases, the distance that the lens barrel 30 and the bobbin 41 move upward along the optical axis direction increases.

Subsequently, when the voltage applied to the coil 42 is cut off, the lens barrel 30 and the bobbin 41 move downward along the optical axis direction by the elastic force of the upper elastic member 20 and the lower elastic member 50. It will return to its original state.

The frame 60 is U-shaped with a central opening through which an optical image can be passed through the image sensor 80, and the frame 60 is located under the lens barrel 30.

As shown in FIG. 2, the first printed circuit board (PCB) 90 is positioned below the lens barrel 30 and includes a window 91 through which an optical image passes and the window 91. The lower portion of the) is formed with a cavity (92) for receiving the image sensor (80).

One side of the upper inner surface of the cavity 92 is electrically connected to one side of the upper surface of the image sensor 80, and the height of the cavity 92 is greater than the thickness of the image sensor 80.

The window 92 is formed to extend on the upper part of the cavity 92 so as to penetrate from the upper inner surface of the cavity 92 to the upper surface of the first printed circuit board 90 and pass the optical image to the image sensor 80. Can be. In this case, the width of the window 91 is smaller than the width of the upper surface of the image sensor 80.

An IR filter 70 for filtering infrared rays is attached to the window 92 of the first printed circuit board 90, and the thickness of the IR filter 70 is greater than or equal to the height of the window 92. In FIG. 1, the thickness of the IR filter 70 is greater than the height of the window 92.

An upper surface of the image sensor 80 is interviewed with a lower surface of the IR filter 70, and an upper side of the image sensor 80 is electrically connected to an inner surface side of the cavity 92 of the first printed circuit board 90.

The image sensor 80 includes a photographing area 81 consisting of a plurality of pixels for sensing an optical image (image information) incident through a plurality of lenses, and a non-imaging area 82 not containing a plurality of pixels. Convert the optical image into an electrical signal.

As shown in FIG. 3, the area of the IR filter 70 is larger than the area of the imaging area 81 of the image sensor 80.

The second printed circuit board 100 is positioned below the first printed circuit board 90 and the image sensor 80 and is a flexible printed circuit board (FPCB) that extends to the outside of the first printed circuit board 90. Printed Circuit Board). A connector (not shown) connected to another element may be attached to an upper surface of the second printed circuit board 100 extending to the outside of the first printed circuit board 90.

As shown in FIG. 4, in the process of screwing the lens barrel 30 and the bobbin 41, the foreign particles 110 attached to the bobbin 41 or the lens barrel 30 are IR filters 70. ) Can fall on top.

In the related art, as shown in FIG. 5A, when the IR filter 70 is mounted on the frame 60 and the foreign material 110 falls on the image sensor 80, the size of the foreign material on the actual screen increases as the angle of view of the foreign material increases. Looks larger than the pixel. In this case, the camera module is determined to be defective.

However, in the present invention, as shown in Figure 5b, when the foreign matter 110 is attached to the IR filter 70 by attaching the IR filter 70 on the upper surface of the image sensor 80, the angle of view of the foreign matter is smaller than in the prior art On the actual screen, the size of the foreign object looks smaller than one pixel.

This is a principle that the image sensor 80 receives light by the angle of view and displays it on the screen. The closer to the image sensor 80, the larger the size of the object and the smaller the distance from the image sensor 80, the smaller the size of the object. When the size of the foreign matter is smaller than one pixel on the actual screen as in the present invention, the camera module may be determined as good quality.

As described above, in the present invention, by attaching the IR filter 70 to the upper surface of the image sensor 80, the foreign matter 110 dropped on the conventional image sensor 80 falls on the IR filter 70 so that the actual screen by the foreign matter. The amount of noise appearing in the image can be reduced.

Therefore, in the present invention, there is an effect that the problems caused by the foreign matter can be improved to good.

Although the embodiments of the present invention have been described in detail above, the scope of the present invention is not limited thereto, and various modifications and improvements of those skilled in the art using the basic concepts of the present invention defined in the following claims are also provided. It belongs to the scope of rights.

10: Case
20: upper elastic member
30: lens barrel
40: Actuator
50: lower elastic member
60: frame
70: IR filter
80: image sensor
90: first printed circuit board
100: second printed circuit board
110: particle

Claims (4)

An image sensor comprising an imaging area and a non-imaging area composed of a plurality of pixels for detecting image information, and converting an incident optical image into an electrical signal;
A printed circuit board having a cavity accommodating the image sensor, the upper side of the cavity being electrically connected to one side of the upper surface of the image sensor;
And an IR filter attached to an upper surface of the image sensor to filter infrared rays. The method of claim 1,
And a window formed on the printed circuit board so as to extend from the upper inner surface of the cavity to the upper surface of the printed circuit board so as to extend on the upper portion of the cavity, wherein the IR filter is attached to the window. The method of claim 1,
And an area of the IR filter is larger than an area of a photographing area of the image sensor. The method of claim 1,
A lens barrel positioned on the IR filter and fixing and protecting the plurality of lenses;
And a bobbin positioned on an upper portion of the IR filter and having a screw thread and an inner circumferential surface formed on an outer circumferential surface of the lens barrel.

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