KR101436574B1 - inspection apparatus and method of LED backlight unit - Google Patents

Abstract

The present invention relates to an LED backlight unit inspection device for aligning an LED chip and a lens constituting an LED module and for checking the distribution state of a fluorescent layer by photographing light output from the LED module after power is applied to the LED module, The present invention relates to a method of manufacturing an LED module, comprising: a power supply for supplying power to the LED module; image acquiring means disposed on the LED module for acquiring an image output from the LED module; And a diffuser disposed between the image acquisition means and the LED module.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an LED backlight unit,

The present invention relates to an apparatus and method for inspecting an LED backlight unit, and more particularly, to an apparatus and method for inspecting an LED backlight unit, And a method of inspecting an LED backlight unit for checking the distribution state of the fluorescent layer.

In general, the demand for display devices has been increasing in various forms. In response to this demand, various display devices such as a liquid crystal display device (LCD), a plasma display panel (PDP), an electro luminescent display (ELD), a vacuum fluorescent display Have been studied and used.

The liquid crystal panel of the LCD includes a liquid crystal layer and a TFT substrate and a color filter substrate facing each other with the liquid crystal layer interposed therebetween. The liquid crystal panel includes a backlight unit that provides light for image display, and an LED module that generates light.

In the LED module, a plurality of light emitting devices are continuously arranged, and a large amount of light emitting devices are used. Therefore, there is a problem in cost increase due to the number of light emitting devices and an increase in electric consumption amount. .

To improve this, an LED module using a light emitting body and a lens covering the light emitting body has been disclosed.

Generally, it is understood that the LED module is configured such that the light emitting units are arranged at regular intervals on a rod formed with a predetermined length and width. The light emitting body includes an LED focusing body on which two or three LEDs are focused and a lens that covers the LED focusing body and uniformly irradiates the light emitted from the LED focusing body in a predetermined direction. Further, the light emitting body is aligned on the same center, that is, on the same optical axis, with respect to the center of the LED focusing element and the lens. It is necessary to check the center alignment state of the LED focusing element and the lens, that is, the alignment state of the optical axis, at the time of manufacturing the light emitting body, because the light supplying efficiency in the light emitting element is lowered when the optical axis of the LED focusing element and the lens are mutually interfered.

SUMMARY OF THE INVENTION The present invention has been conceived in order to solve the problems described above, and it is an object of the present invention to provide an LED module, in which light output from an LED module is sequentially passed through a diffuser having different diffusivities and scattering degrees, And an LED backlight unit inspection apparatus and method capable of determining the distribution state of the fluorescent layer.

According to an aspect of the present invention, there is provided an apparatus for inspecting an LED backlight unit including a power supply unit for supplying power to an LED module, Moving means for moving the image acquiring means, and diffuser disposed between the image acquiring means and the LED module.

According to an embodiment of the present invention, the diffuser has a polyprism shape having a quadrangular or hexagonal cross section, the scattering degree and the diffusibility of the neighboring surfaces are different from each other, The unevenness due to the defective alignment of the LED chip and the lens and the blurring due to the non-uniform formation of the fluorescent layer are checked.

According to an embodiment of the present invention, the display device further includes a rotation driving unit that rotates the diffuser about the longitudinal direction and adjusts a surface through which the image output from the LED module is transmitted.

According to an embodiment of the present invention, the image acquiring means is provided with a line scan camera.

According to another aspect of the present invention, there is provided a method of inspecting an LED backlight unit including a first inspection step of inspecting an image output from an LED module through a first surface of the diffuser, And a second inspection step of inspecting an image output from the diffuser through a second surface neighboring the first surface of the diffuser and having a scattering degree and a diffusing degree different from the first surface.

According to the apparatus and method for inspecting the LED backlight unit of the present invention, the light output from the LED module is successively passed through a diffuser having different diffusivities and scattering degrees, and then the LED chip and the lens are aligned And the distribution state of the fluorescent layer can be determined, so that a plurality of tests can be performed in one equipment.

In addition, the diffuser is not replaced, and one diffuser is rotated to diffuse diffusing and diffusing light to the light output from the LED module, thereby improving inspection speed and productivity.

1 is a configuration diagram of an LED backlight unit inspection apparatus according to an embodiment of the present invention;
Fig. 2 is a perspective view showing an example of the diffuser shown in Fig. 1,
Fig. 3 is a perspective view showing another example of the diffuser shown in Fig. 1,
4 is a configuration diagram of an LED backlight unit testing apparatus according to another embodiment of the present invention.

The present invention will now be described in detail with reference to the accompanying drawings. Here, the same reference numerals are used for the same components, and repeated descriptions and known functions and configurations that may obscure the gist of the present invention will not be described in detail. Embodiments of the present invention are provided to more fully describe the present invention to those skilled in the art. Accordingly, the shapes and sizes of the elements in the drawings and the like can be exaggerated for clarity.

1 is a configuration diagram of an LED backlight unit testing apparatus according to an embodiment of the present invention. 1, an inspection apparatus for an LED backlight unit according to an exemplary embodiment of the present invention includes a printed circuit board 11, a plurality of LED chips 12 mounted on the printed circuit board 11 at regular intervals And a power supply unit (not shown) for supplying power to the LED module 10. The LED module 10 includes an LED chip 12, a fluorescent layer 13 and a lens 14 formed on the LED chip 12, An image obtaining means 120 disposed on the LED module 10 for obtaining an image output from the LED module 10 and a moving means for moving the image obtaining means 120 And a diffuser 140 disposed between the image acquiring unit 120 and the LED module 10. [

First, the power supply unit 110 supplies power required for light emission of the LED module 10, and can supply 10mA to 200mA and 150V power. When a standard current (for example, 150 mA) necessary for the operation of the LED module 10 is applied to the power supply unit 110, light emitted from the LED chip 12 is transmitted through the fluorescent layer 13 and the lens 14 And is displayed outside the lens 14. Therefore, the current supplied to the LED module 10 can be variously adjusted within a range that allows light emitted from the LED chip 12 to be recognized outside the lens 14.

The image acquiring unit 120 is disposed on the LED module 10 and includes an image sensor to supply power to the LED module 10 from the power supply unit 110, An image of the emitting LED module 10 is obtained. Here, the image acquiring unit 120 preferably operates according to the power supply from the power supply unit 120 to the LED module 10. That is, the image acquiring unit 120 can operate at the moment when power is supplied to the power supply unit 120 to emit light. The image input to the image acquiring unit 120 is transmitted to a reading device for detecting whether or not the LED module 10 is defective through image analysis. According to an embodiment of the present invention, the image acquiring unit 120 may be a variety of known imaging apparatuses. However, in order to facilitate image acquisition of the LED module 10 in which the light emitting elements are arranged in a line form, And can be equipped with a camera.

The moving means 130 moves the image obtaining means 120 to move the image obtaining means 120 for taking an image of the LED module 10 in the horizontal direction from the top of the LED module 10 to be inspected . That is, the moving unit 130 moves the image obtaining unit 120 in a direction perpendicular to the optical axis of the LED chip 12, and the image obtaining unit 120 moves the plurality of So that the image of the LED module 10 can be acquired. The moving means 130 may include a conveying member fixed to the image acquiring means 120 and a rail member for mounting the conveying member and guiding the conveyance in the front, have.

A diffuser 140 is disposed between the image acquisition means 130 and the LED module 10. Generally, light passing through the diffuser 140 is scattered and diffused. The light outputted from the LED module 10 is not diffused and scattered well and the uniformity of light is lowered so that the diffuser 140 is disposed between the image obtaining means 130 and the LED module 10 The light emitted from the LED module 10 is scattered or diffused to increase the radiation angle, increase the uniformity of the light, and cause the image to be incident on the image acquisition means 130.

FIG. 2 is a perspective view showing an example of the diffuser shown in FIG. 1, FIG. 3 is a perspective view showing another example of the diffuser shown in FIG. 1, and FIG. 4 is a perspective view of the LED backlight unit inspection apparatus according to another embodiment of the present invention. FIG.

According to an embodiment of the present invention, the diffuser 140 has a polyprism shape having a rectangular or hexagonal cross section, and the scattering degree and the diffusing degree of the neighboring surfaces 141 and 142 are different from each other, Uniformity of the fluorescent layer 13 due to uneven defects due to defective alignment between the LED chip 12 and the lens 14 while controlling the surfaces 141 and 142 through which the image output from the LED module 10 is transmitted, Check for blurring due to formation.

When the cross section of the diffuser 140 is formed in a square shape, the diffuser 140 may have two scattering degrees and diffusions. When the cross section is formed in a hexagonal shape, the diffuser 140 has three scattering degrees and Diffusion degree can be provided. This is proportional to the number of paths that the image output from the LED module 10 can pass through. When the cross-section of the diffuser 140 is formed into a quadrangle, there are two opposing planes, When the cross-section of the diffuser 140 is formed into a hexagonal shape, three scattering planes and diffusions can be provided since there are three facing planes. The difference between the scattering degree and the diffusing degree can be freely changed by using the thickness, the surface or the inner surface processing of the diffuser 140, and the material characteristics.

At this time, the diffuser 140 of the polygonal columnar type rotates about the longitudinal axis, for example, the diffuser 140 of the rectangular column rotates by 90 degrees, and the diffuser 140 of the hexagonal column rotates by 60 degrees The scattering degree and the diffusing degree of the diffuser 140 through which the image is transmitted can be changed by changing the path through which the image output from the LED module 10 can be transmitted. In addition, the diffuser 140 is provided in the form of a flat plate and is processed to have different scattering degree and diffusing degree for each region, and when the diffuser 140 is moved in the horizontal direction, the image output from the LED module 10 is transmitted The scattering degree and the diffusing degree can be made different by changing the region.

When the vision inspection is performed by varying the scattering degree and the diffusing degree as described above, it is possible to prevent blurring due to uneven defects of the LED chip 12 and the lens 14 and blurring due to non-uniform formation of the fluorescent layer 13 Can be inspected by a single apparatus.

According to an embodiment of the present invention, a rotation driving unit 150 that rotates the diffuser 140 around the longitudinal direction and adjusts the surfaces 141 and 142 through which the image output from the LED module 10 is transmitted, . The rotation driving unit 1500 may be provided with a motor or the like and rotates the diffuser 140 about the longitudinal direction of the diffuser 140. The path through which the image output from the LED module 10 can be transmitted is changed, When the rotation driving unit 150 is provided, control means for controlling the rotation angle, speed, and the like of the rotation driving unit 150 may be additionally provided.

Meanwhile, the inspection method of the LED backlight unit according to an embodiment of the present invention uses the above-described inspection apparatus, and transmits the image output from the LED module 10 through the first surface 141 of the diffuser 140 And the diffuser 140 is rotated so that the image output from the LED module 10 is adjacent to the first surface 141 of the diffuser 140 and the first surface 141 of the diffuser 140, And a second inspection step of inspecting and inspecting the second surface 142 having a different scattering degree and diffusivity.

As described above, in the first inspection step, the image acquiring means 120 disposed at the upper end of the LED module 10 supplied with power is moved in the horizontal direction by the action of the conveying means 130, Thereby obtaining an image of the light. At this time, the diffuser 140 is adjusted to pass the light output from the LED module 10 to the first surface 141 of the diffuser 140 disposed between the LED module 10 and the image acquiring unit 120 , And photographs the image with the image acquiring means (120). Meanwhile, in the secondary inspection step, as in the first inspection step, the image acquisition unit 120 disposed at the upper end of the powered LED module 10 is moved in the horizontal direction by the action of the conveying unit 130, And obtains an image of the light output from the light source 10. At this time, the LED module 10 is mounted on the second surface 142 having a different scattering degree and diffusing degree from the first surface 141 of the diffuser 140 through which the light output from the LED module 10 is passed in the first inspection step And the image obtained by the image acquiring unit 120 is photographed by the image acquiring unit 120. The image acquiring unit 120 acquires the image from the second surface 142 of the diffuser 140 by rotating the diffuser 140 by a predetermined angle.

Since the diffuser 140 has a polyprism shape having a rectangular or hexagonal cross section and the scattering degree and diffusibility of the neighboring surfaces 141 and 142 are different from each other, For example, the diffuser 140 of the quadratic column rotates by 90 degrees and the diffuser 140 of the hexagonal column rotates by 60 degrees so that the image output from the LED module 10 is transmitted through the diffuser 140 The diffusing degree and diffusing degree of the diffuser 140 through which the image is transmitted can be set differently.

As described above, when a plurality of tests are performed in a state in which the conditions of the scattering degree and the diffusivity are set differently, a combination that is not detected in the first test can be detected in the second test, and the testability can be improved. For example, if an unevenness phenomenon due to defective alignment between the LED chip 12 and the lens 14 is detected in the first inspection, in the secondary inspection, the blurring phenomenon due to non-uniform formation of the fluorescent layer 13 is checked can do.

According to the apparatus and method for inspecting an LED backlight unit according to the present invention, the light output from the LED module is sequentially passed through a diffuser having different diffusivities and scattering degrees, It is possible to determine the alignment state of the lens with respect to the optical axis and the distribution state of the fluorescent layer so that a plurality of inspections can be performed in one equipment and the diffuser can be rotated without rotating the diffuser, It is possible to improve the inspection speed and productivity by varying the scattering degree.

It will be apparent to those skilled in the art that various modifications, substitutions and substitutions are possible, without departing from the scope and spirit of the invention as disclosed in the accompanying claims. will be. Therefore, the embodiments disclosed in the present invention and the accompanying drawings are intended to illustrate and not to limit the technical spirit of the present invention, and the scope of the technical idea of the present invention is not limited by these embodiments and the accompanying drawings . The scope of protection of the present invention should be construed according to the following claims, and all technical ideas falling within the scope of the same shall be construed as falling within the scope of the present invention.

10: LED module
11: printed circuit board
12: LED chip
13: Fluorescent layer
14: Lens
110: Power supply
120: Image acquisition means
130: Moving means
140: diffuser
141: first side
142: second side
150:

Claims (5)

An apparatus for inspecting an LED backlight unit using an LED module including a printed circuit board, a plurality of LED chips mounted on the printed circuit board at regular intervals, and a fluorescent layer and a lens formed on the LED chip,
A power supply unit for supplying power to the LED module;
Image acquisition means disposed on the LED module for acquiring an image output from the LED module;
Moving means for moving the image acquiring means;
And a diffuser disposed between the image acquiring unit and the LED module and having a polyprism shape having a rectangular or hexagonal cross section and having a scattering degree and a diffusing degree different from each other, The diffuser adjusts a surface through which the image output from the LED module is transmitted to rotate to check for a blurring phenomenon due to an alignment defect of the LED chip and a lens and a blurring phenomenon due to nonuniform formation of the fluorescent layer LED backlight unit inspection device. delete The method according to claim 1,
Further comprising a rotation driver for rotating the diffuser about the longitudinal direction to adjust the surface through which the image output from the LED module is transmitted. The apparatus of claim 1, wherein the image acquiring unit is a line scan camera. A method of inspecting an LED backlight unit using an inspection apparatus according to claim 1,
A first inspection step of inspecting an image output from the LED module through a first surface of the diffuser;
And a second inspection step of rotating the diffuser to inspect an image output from the LED module through a second surface adjacent to the first surface of the diffuser.

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