KR100705704B1 - Led array type lenz and backlight apparatus using a thereof - Google Patents

Abstract

The present invention is to provide an LED array lens and a backlight device using the same, which can implement a high brightness while improving the uniformity of light, the LED array lens of the present invention has a top emitting surface inclined in the V shape, the bottom The surface has one or more LED insertion grooves so that the light emitting diodes (LEDs) can be inserted at predetermined intervals from each other. In addition, the backlight device using the LED array lens of the present invention is a backlight device installed under the liquid crystal layer to output a light source, a plurality of LED array lenses arranged side by side at a predetermined interval from each other, and the LED array lens It is characterized in that it comprises a diffusion sheet which is installed on the upper portion, and a frame for fixing and supporting the LED array lens and the diffusion sheet.

LED lens, backlight

Description

LED array lens and backlight device using the same {LED ARRAY TYPE LENZ AND BACKLIGHT APPARATUS USING A THEREOF}

1 is a perspective view of an LED array lens according to an embodiment of the present invention

2 is a side view of the lens for the LED array according to an embodiment of the present invention

3a to 3c is another illustration of the lens for the LED array according to an embodiment of the present invention

4A to 4C are perspective views of a lens for an LED array according to another embodiment of the present invention.

5a to 5d are exemplary views for explaining the shape of the LED insertion groove according to the LED array lens of the present invention.

6 is a state diagram in which a plurality of lenses for LED array of the present invention is repeatedly arranged

7 is a graph showing luminance measured values in space according to the LED array lens of the present invention.

8 is a graph showing luminance measurement values on a plane according to the LED array lens of the present invention.

9 is a graph showing the viewing angle measurement value according to the LED array lens of the present invention

10 is a block diagram of a backlight device using the LED array lens of the present invention

* Explanation of symbols for main parts of drawings *

100: LED array lens 200: LED insertion groove

300: diffusion sheet 400: frame

The present invention relates to a lens for a light emitting diode (LED) array, and more particularly, to an LED array lens and a backlight device using the same, which is excellent in workability and suitable for high brightness.

Recently, as consumers' desire for large size and high resolution display devices increases, development of thin flat panel display devices in place of weight and bulk CRT (Cathode Ray Tube) is urgently needed, and one of such flat display devices has developed a liquid crystal display device. It became.

Such a liquid crystal display device requires a backlight unit (BackLight Unit), which is a separate light source because it displays a screen by using a liquid crystal (liquid crystal) that does not emit light by itself, and recently, a large area and high resolution liquid crystal display In order to realize the device, improvement of screen brightness, efficiency, power consumption, optical uniformity, color reproducibility, viewing angle, thin structure, and price competitiveness are urgently required.

On the other hand, the quality of the screen in the liquid crystal display device is absolutely affected by the light source. This is because the liquid crystal display itself does not have a light emitting capability. Therefore, the liquid crystal of the conventional TN mode (Twisted Nematic Mode) or the STN mode (Super Twisted Nematic Mode) is mainly the reflection type using an external light source.

However, as the screen becomes larger and the consumer's demand for high quality increases, rather than installing the light source on the front or side, the backlight method is mainly used to install the light source on the back of the screen and display the image as light passes through the liquid crystal panel. In this case, CCFL (Cold Cathode Fluorescent Lamp), HCFL (Hot Cathode Fluorescent Lamp), etc. are used as the light source.In particular, CCFL (Cold Cathode Fluorescent Lamp), which has long life, low power consumption, and can be manufactured thinly Used.

The light source may be installed in a direct type so that a plurality of light sources directly illuminate the screen, or may be installed in at least one side of the liquid crystal panel in an edge manner to illuminate the screen by a light guide plate and a reflecting plate. In this case, a diffusion sheet may be provided between the liquid crystal panel and the light source in order to increase luminance uniformity of the screen.

However, in the case of the cold cathode fluorescent lamp used in the liquid crystal display of the large screen, since the main component of the gas encapsulated in the discharge tube is mercury, it is easy to form amalgam by combining with a metal, thereby reducing the lifetime of the lamp, There was a problem that the change in luminance with the change is severe. In particular, due to the growing interest in the environment, its use has been proposed due to problems such as the disposal of heavy mercury, a toxic heavy metal, and above all, there was a limitation in implementing various colors due to high power consumption and uneven brightness. .

In addition, the space occupied by the backlight unit is difficult to miniaturize the backlight unit, and as the uniformity of luminance decreases, there is a problem in that the uniformity of light by the diffuser plate needs to be adjusted in proportion to the brightness of the light source.

The present invention has been made to solve the above problems, and an object thereof is to provide an LED array lens and a backlight device using the same, which can implement high brightness and high brightness.

LED array lens according to an embodiment of the present invention for achieving the above object has an upper exit surface inclined in the V-shape, the light emitting diode (LED) can be inserted at a predetermined interval on the bottom surface It is characterized in that it has one or more LED insertion groove.

In addition, the LED array lens according to another embodiment of the present invention is the upper exit surface is composed of a reverse pyramid-shaped groove, the bottom surface at least one light emitting diode (LED) can be inserted at a predetermined interval from each other It is characterized by having an LED insertion groove.

Here, the V-shaped upper exit surface is characterized in that the inclined downward so that the angle of the vertex is 60 ° ~ 120 ° range.

In addition, the vertex of the top surface and the top surface of the LED insertion groove has a spacing of 0.1mm ~ 3mm range, the shape of the ceiling surface of the LED insertion groove is polygonal, hemispherical, cylindrical, conical and a plurality of vertex angles. It is characterized by having any one of conical shape.

In addition, it has both side exit surface in contact with the bottom surface, the side exit surface is characterized in that it has a slope in the range of 50 ~ 120 ° with respect to the bottom surface.

Meanwhile, a backlight device using an LED array lens according to an exemplary embodiment of the present invention is a backlight device installed under a liquid crystal layer and outputting a light source, and includes a plurality of LED array lenses arranged side by side at a predetermined interval from each other. And a diffusion sheet installed on the LED array lenses, and a frame for fixing and supporting the LED array lens and the diffusion sheet.

Here, the LED array lens has a plurality of LED insertion grooves having a top exit surface inclined in a V-shape and are arranged at predetermined intervals on the bottom surface so that a light emitting diode (LED) can be inserted therein; It characterized in that it comprises a LED inserted into the groove, the upper exit surface comprises a reverse pyramid-shaped groove is configured.

In addition, a predetermined air layer is further provided between the top of the LED and the ceiling surface of the LED insertion groove.

[Example]

Hereinafter, an LED array lens and a backlight device using the same according to an embodiment of the present invention will be described with reference to the accompanying drawings.

1 is a perspective view of an LED array lens according to an embodiment of the present invention, Figure 2 is a side view.

1 and 2, the LED array lens 100 of the present invention has a tapered shape in which the top exit surface is inclined at a predetermined angle, and the light emitting diodes (LEDs) are spaced at predetermined intervals from the bottom surface. One or more LED insertion grooves 200 are formed to be inserted therein.

Here, the material of the LED array lens 100 is made of a transmissive or semi-permeable resin, for example, acrylic resins and resins such as polycarbonate (Polycabonate) or polymethyl methacrylate (PMMA) (Resin) and the like.

The upper exit surface of the LED array lens 100 preferably has a "V" shape in which both sides thereof are inclined downward toward the vertex about the vertex of the center portion. At this time, the angle (α) formed by the vertex has a range of about 40 ~ 140 °, more preferably has a range of 60 ~ 120 °. For reference, Table 1 below shows luminance values for angles of vertices according to an embodiment of the present invention, which is 60 when the vertex angle α is 60 ° or less and when the vertex angle α is 120 ° or more. It can be seen that the luminance value is markedly high for each measurement point within the range of ˜120 °.

TABLE 1

    Luminance angle Point 1 Point 2 Point 3 Point 4 Point 5 Point 6 50 degrees 28974 28911 38658 36582 31756 30869 60 degrees 49525 49106 59352 58632 53579 54039 70 degrees 68531 71165 65250 64072 59290 65661 80 degrees 73039 72670 73039 73436 75004 73438 90 degrees 81645 80652 82157 81799 80985 81448 100 degrees 71221 72515 74223 73453 73609 73004 110 degrees 65250 63805 61841 62622 63920 63488 120 degrees 49525 47339 42666 47339 75621 52498 130 degrees 29483 30158 33746 34963 29869 26435

On the other hand, the LED array lens 100 according to an embodiment of the present invention, as shown in Figure 3a to 3c, having both side exit surface in contact with the bottom surface, the side exit surface is 50 with respect to the bottom surface It is desirable to have a slope in the range of ˜120 °.

In addition, the LED array lens 100 according to the embodiment of the present invention, as shown in Figures 4a to 4c, to form the shape of the upper exit surface in the form of a depression in the reverse pyramid shape instead of the letter "V" As such, as shown in FIGS. 1 and 2, the upper emission surface may be formed in an inverted pyramid shape as shown in the “V” shape or FIGS. 4A to 4C, thereby emitting light emitted from the light emitting diodes (LEDs) in all directions. Since it can spread evenly, the brightness can be improved by that much.

In addition, the LED array lens 100 according to an embodiment of the present invention has a predetermined width (W) such that the LED insertion groove 200 formed in the bottom surface can be inserted into the LED, the ceiling surface is 5A to 5D, the LED array lens 100 may protrude or be formed in a concave shape toward the upper exit surface, in addition, including a polygonal shape, hemispherical, cylindrical, conical and It can also form in various ways, such as a cone with a some vertex angle.

At this time, it is preferable to maintain a gap of about 0.1mm to 3mm between the ceiling surface of the LED insertion groove 200 and the vertex of the upper exit surface, the shape and the LED array of the ceiling surface of the LED insertion groove 200 Obviously, the angles of both side exit surfaces of the lens 100 may be combined in various forms.

Meanwhile, a predetermined air layer (not shown) may be formed between the upper end of the LED to be inserted into the LED insertion groove 200 and the ceiling surface of the LED insertion groove 200. If the air layer is formed as described above, the refractive index between the material constituting the LED array lens 100 and the air layer is different from each other to further increase the light diffusion effect, the presence or absence of the air layer is the LED insertion groove 200 It depends on what kind of LED you insert.

The light emitting diode inserted into the LED insertion groove 200 may be configured as a light emitting diode of red (R), green (G), and blue (B), or may be configured as a single color of white. In this case, the light emitting diodes (LEDs) inserted into the LED insertion grooves 200 are arranged in a line with a light emitting diode (LED) in the form of a point light source as shown in FIG. 6, as if a plurality of bar fluorescent lamps are installed. A light emitting diode (LED) array in the form of a line light source is formed, and when a plurality of light emitting diode arrays having the line light source form are arranged side by side again, the light emitting diode in the form of a surface light source is generally formed. LED) array can be configured.

For reference, in the exemplary embodiment of the present invention, a plurality of light emitting diode arrays having a linear light source shape are arranged in a straight line to implement a light emitting diode array having a surface light source shape, but the light emitting diode arrays are not necessarily arranged in a straight line shape. As long as the light emitting diode array can be formed, the light emitting diode array in the form of a linear light source may be configured in the form of concentric circles.

In addition, the number of light emitting diodes (LEDs) to be inserted into the LED insertion grooves 200 may be increased or decreased according to the size of the liquid crystal panel or the size of the LED array lens 100, and the gap between the light emitting diodes is also the size of the panel. Can be maintained from several mm to several tens of millimeters.

On the other hand, Figure 7 is a graph showing the result of measuring the brightness in the space according to the LED array lens of the present invention configured as described above, Figure 8 is a graph showing the result of measuring the brightness on the plane, Figure 9 As a graph illustrating a viewing angle according to the LED array lens of the present invention, as shown in FIG. 8, it can be seen that the average luminance value is as high as 50,000 cd / m 2, and the range of the viewing angle is at least 150 °. It can be seen that.

Table 2 below shows the luminance values in the measured space after implementing the backlight device using the LED array lens according to an embodiment of the present invention, Table 3 is the average for each measuring point according to Table 2 The luminance value is compared with that of a typical backlight device.

TABLE 2

        Number of spots Point 5 Point 10 Point 15 Point 21 One 57608.38 58067.19 67034.07 0 2 47268.92 61832.90 59579.71 0 3 49524.77 68530.94 64071.82 0 4 59534.74 61018.59 59288.29 0 5 54199.98 59410.74 62850.23 0

TABLE 3

        Branch division Point 5 (SUM) Point 10 (SUM) Point 15 (SUM) Point 21 (SUM) Invention (Example) 53627.35 61772.07 62564.82 0 Prior art 41685.76 48643.92 49397.84 0

As shown in Table 2 and Table 3 above, when comparing the brightness value in the case of implementing the backlight device using the lens for the LED array according to an embodiment of the present invention and the brightness value of the conventional general backlight device It can be seen that the luminance value of the LED array lens of the present invention is markedly high.

On the other hand, Table 4 below shows the brightness value on the plane after implementing the backlight device by using the lens for the LED array according to an embodiment of the present invention, Table 5 is the brightness per measurement point according to Table 4 As a result of averaging the value and comparing the brightness value on the plane of a general backlight device, as shown in Tables 4 and 5 below, it can be seen that the brightness value on the plane is also markedly higher than in the prior art. have.

TABLE 4

        Branch turn Point 5 Point 10 Point 15 POINTS 20 Point 25 One 159074.6 192887.3 199108.0 185501.0 138993.0 2 150860.9 181036.5 197650.6 189799.7 141179.8 3 157299.2 179346.2 191449.8 191167.0 149473.6 4 162403.5 193940.3 209948.4 209647.0 162879.8 5 158451.1 177762.1 211513.4 175940.5 151968.8

TABLE 5

        Branch division Point 5 (SUM) Point 10 (SUM) Point 15 (SUM) Point 20 (SUM) Point 25 (SUM) Invention (Example) 157617.86 184994.48 201934.04 190411.04 148898.96 Prior art 122569.45 139825.34 163672.68 154289.14 115981.04

Hereinafter, a backlight device using the LED array lens as described above will be described. That is, when the above-described LED array lens is applied as a backlight device of the liquid crystal display device, the backlight device may be configured as shown in FIG.

10 is a block diagram of a backlight device using the LED array lens of the present invention, a plurality of LED array lenses (100a) arranged side by side at a predetermined interval from each other, and the diffusion is installed on the LED array lenses It comprises a sheet 300, a frame 400 for fixing and supporting the LED array lens 100 and the diffusion sheet 300.

In this case, the diffusion sheet 300 installed above the LED array lens 100a is for uniformly diffusing high intensity light output from the LED array lens 100, and is predetermined from the LED array lens 100a. It is desirable to maintain the spacing.

A lower surface of the LED array lens 100a may further include a reflective sheet (not shown) to prevent light output from the LED array lens 100a from being lost to the lower surface of the lens.

The LED array lens 100a may be formed of a transmissive or semi-permeable resin. For example, acrylic resins such as polycarbonate or polymethyl-methacrylate (PMMA) and resins may be used. Or the like.

In addition, the upper surface exit surface of the LED array lens 100a preferably has a "V" shape inclined downward toward the vertex with respect to the vertex of the center portion, or has a shape inclined in the reverse pyramid shape. At this time, when the upper exit surface has a "V" shape, the angle (α) formed by the vertex has a range of about 60 ~ 140 °, more preferably has a range of 70 ~ 120 °.

In addition, the LED array lens 100 has both side exit surfaces in contact with the bottom surface preferably has a slope in the range of 50 ~ 120 ° with respect to the bottom surface, the LED insertion groove 200 is formed on the bottom surface Silver has a predetermined width (W) to the extent that the LED can be inserted is formed in the form of a depression or protruding toward the top surface exit surface. In addition, the top of the LED insertion groove 200 may have a shape of any one of a hemispherical, cylindrical, conical and a plurality of cones, including a polygonal shape of. At this time, the LED insertion groove 200 and the vertex is preferably maintained at a distance of about 0.1mm to 3mm.

As such, the backlight device using the LED array lens of the present invention installs a diffusion sheet on a lens made of light emitting diode arrays emitting high intensity light, and uniformly diffuses the light output from the light emitting diode array. The result of improving the luminance can be achieved.

Although preferred embodiments of the present invention have been described above, it is clear that the present invention can use various changes, modifications, and equivalents, and that the above embodiments can be appropriately modified and applied in the same manner. Accordingly, the above description does not limit the scope of the invention as defined by the limitations of the following claims.

As described above, the LED array lens of the present invention and a backlight device using the same need only be inserted into the LED insertion groove after forming an LED insertion groove into which a light emitting diode (LED) can be inserted into the lower surface of the lens. Workability according to the production becomes very easy.

In addition, it is possible to implement high brightness with only a small number of LEDs, thereby achieving cost reduction effects, and improving light uniformity and viewing angle.

Claims (14)

It has a top emitting surface inclined in a V-shape, at least one LED insertion groove in the bottom surface to be inserted into the light emitting diode (LED) at a predetermined interval from each other, the shape of the ceiling surface of the LED insertion groove Lens for the LED array, characterized in that the polygonal shape. According to claim 1, wherein the V-shaped upper exit surface of the LED array lens, characterized in that the inclined downward so that the angle of the vertex is in the range of 60 ° ~ 120 °. The lens of claim 2, wherein an upper end of the LED insertion groove and the vertex maintain an interval in a range of about 0.1 mm to about 3 mm. delete The lens of claim 1, wherein the ceiling surface of the LED insertion groove has any one of a hemispherical shape, a cylinder shape, a cone shape, and a conical shape having a plurality of vertices. The lens for an LED array according to claim 1 or 2, wherein the LED array lens is made of a transmissive or semi-permeable resin. The LED array according to claim 1 or 2, further comprising side surface exit surfaces in contact with the bottom surface, wherein the side surface exit surface has an inclination in a range of 50 ° to 120 ° with respect to the floor surface. Use lens. The upper emission surface is composed of a reverse pyramid-shaped groove, the bottom surface lens for LED array, characterized in that it has one or more LED insertion grooves so that the light emitting diodes (LED) can be inserted at a predetermined interval from each other. In the backlight device which is provided under the liquid crystal layer to output a light source, A plurality of LED array lenses arranged side by side at a predetermined interval from each other; A diffusion sheet installed on the LED array lens; And a frame for fixing and supporting the LED array lens and the diffusion sheet. The method of claim 9, wherein the LED array lens, An LED array lens having a plurality of LED insertion grooves having a top emitting surface inclined in a V shape and arranged at predetermined intervals on a bottom thereof so that a light emitting diode (LED) can be inserted therein; And a LED inserted into the LED insertion groove. The method of claim 9, wherein the LED array lens, An LED array lens having a plurality of LED insertion grooves so that the upper exit surface is composed of inverted pyramid-shaped grooves and is disposed at predetermined intervals on the bottom surface so that the light emitting diodes (LEDs) can be inserted; And a LED inserted into the LED insertion groove. The backlight device according to claim 10 or 11, wherein a predetermined air layer is provided between an upper end of the LED and a ceiling surface of the LED insertion groove. 12. The backlight device according to claim 10 or 11, further comprising a reflective sheet on a lower surface of the LED array lens.  12. The backlight device according to claim 10 or 11, wherein the ceiling surface of the LED insertion groove has any one of a hemispherical shape, a cylinder shape, a cone shape, and a conical shape having a plurality of vertices.

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