KR100959660B1 - Surface emitting device - Google Patents

Abstract

A plurality of light emitting diodes disposed on the substrate and mounted so that the light emitting surface is laterally facing the substrate so that the brightness and color are uniform and the thickness is minimized, and for dispersing light emitted from the light emitting diode toward the front surface of the substrate. Provided is a surface light emitting device including at least one reflective structure.

Surface Emitting, Side Light Emitting Diode, Reflective Structure, Reflective Surface, Substrate, Side

Description

Surface Light Emitting Device {SURFACE EMITTING DEVICE}

The present invention relates to a surface light emitting device. More particularly, the present invention relates to a surface light emitting device capable of realizing a surface light source having excellent uniformity while reducing thickness through side light emission of a light emitting diode.

In general, a surface light emitting device using a light emitting diode (LED) as a point light emitting source or a cold cathode fluorescent lamp (CCFL) as a light emitting source is used as a surface light source for a backlight unit of a lighting or flat panel display.

As a structure for implementing a surface light source, a technique of arranging a plurality of light emitting sources or point emitting sources on a plane and distributing light uniformly on a surface through a diffusion sheet or a prism sheet is disclosed.

However, the conventional technique described above may cause uneven luminance distribution since the light emitting source is disposed directly below the light emitting surface. In order to uniformly mix the light emitted from the light emitting source, it is necessary to space the distance between the light emitting source and the light emitting surface by a minimum distance necessary for mixing the light. Therefore, the above technique has a disadvantage in that the overall thickness of the surface light emitting device becomes thick.

A technology of utilizing a light guide plate as a method of realizing a thin surface light source by improving this has been disclosed.

The prior art has a structure in which light is emitted through a side surface of a flat light guide plate by arranging a front light source or a point light source on the side of the light guide plate. However, this technology has a problem that the brightness of the entire light emitting surface is not uniform because the distance from which the light of the light source or the point light source reaches from the side of the light guide plate to the center becomes farther. In addition, since the mixing of light with neighboring light sources is not easy, there are many problems to realize a large surface light source or a uniform surface light source.

This provides a surface light emitting device that can minimize the thickness while uniform brightness and color.

The present invention also provides a surface light emitting device capable of smoothly mixing various colors of a light emitting diode so as to consistently implement a desired color of a surface light source.

In addition, there is provided a surface light emitting device that can lower the manufacturing cost.

To this end, the apparatus includes a plurality of light emitting diodes disposed on a substrate and mounted so that the light emitting surface faces the substrate, and at least one reflection for dispersing light emitted from the light emitting diodes to the light emitting plane toward the front side of the substrate. It may include a structure.

Therefore, the light emitted from the light emitting diode is not concentrated in the light emitting plane of the front surface, but is dispersed through the reflecting structure and uniformly mixed in the light emitting plane of the front surface to minimize the distance between the light emitting source and the light emitting plane, thereby achieving uniform mixing. do.

The light emitting diode may have a structure in which the light emitting surface is disposed perpendicular to the light emitting plane. In addition, the light emitting diode may have a structure in which the light emitting surface is inclined with respect to the light emitting plane.

The light emitting diodes may be arranged at intervals along the reflective structure.

The light emitting diode may be a side light emitting diode having a light emitting surface formed on a side thereof. In addition, the light emitting diode may be a front light emitting diode having a light emitting surface formed on a front surface thereof. In this case, the apparatus may have a structure in which an auxiliary substrate on which a front light emitting diode is mounted is mounted such that a light emitting surface of the front light emitting diode faces a side of the substrate.

The light emitting diode may be a structure disposed to face the reflective structure.

In this device, a separate reflective structure may be further formed on the substrate for at least one surface other than the light emitting surface of the light emitting diode.

In addition, the reflective structure may be a structure in which the side is inclined to form a reflective surface.

The reflective surface of the reflective structure may be formed in a flat or curved or non-planar form. In addition, the reflective surface of the reflective structure may be a structure that totally reflects light or partially transmits and only partially reflects light.

The reflective structure may be an elliptical cone-shaped structure in which the side is inclined to form a reflective surface.

The reflective structure may be a conical structure in which the side is inclined to form a reflective surface.

The reflective structure may be a straight structure in which at least one side is inclined to form a reflective surface.

The reflective structure may be a combination of an elliptical or conical structure and a linear structure.

The reflective structure may be installed to face the light emitting surface of the light emitting diode.

On the other hand, the reflective structure may be a structure having a reflective surface curved concave toward the light emitting plane. In such a structure, a light emitting diode may be installed on the reflective surface such that the light emitting surface is obliquely installed toward the bottom of the reflective surface.

In addition, the apparatus may further include a reflective sheet attached to the substrate.

In addition, the apparatus may include a board in which the reflective structure is parallel to the light emitting plane and on which the reflective surface is formed. In this case, the light emitting diode may have an emission surface obliquely installed toward the reflection surface. The light dispersing lens may be further provided on the reflective surface.

In addition, the device is made of a reflective sheet to which the reflective structure is attached on the substrate, the reflective sheet may be a structure to form a reflective surface inclined upward from the substrate. The reflective sheet may have a structure in which a tip thereof covers an upper surface of a neighboring light emitting diode.

On the other hand, the device may further include a diffusion sheet is installed on the light emitting plane of the front surface of the substrate for diffusing light.

The apparatus may further include an optical sheet installed on the light emitting plane of the front surface of the substrate to increase the brightness of the light.

The apparatus may further include a protective sheet installed on the light emitting surface of the front surface of the substrate to protect the light emitting surface.

As such, the device minimizes the distance from the light emitting source to the light emitting plane so that the light is evenly mixed, thereby providing uniform surface light emission while minimizing the thickness of the device.

In addition, by uniformly arranging various colors of the light emitting diode to control a constant color and brightness, there is an advantage that can utilize all kinds of side light emitting diodes. In addition, this advantage increases the production yield of the light emitting diode which has the greatest influence on the cost of the surface light emitting device, thereby providing a more competitive surface light source device and contributing to the improvement of productivity and quality. There is an advantage to doing that.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings so that those skilled in the art may easily implement the present invention. As those skilled in the art would realize, the described embodiments may be modified in various different ways, all without departing from the spirit or scope of the present invention.

The drawings are schematic and illustrate that they are not drawn to scale. The relative dimensions and ratios of the parts in the figures have been exaggerated or reduced in size for clarity and convenience in the figures and any dimensions are merely exemplary and not limiting. And the same structure, element or part that appears in more than one figure the same reference numerals are used in different embodiments to indicate corresponding or similar features.

The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. As used herein, the singular forms “a,” “an,” and “the” include plural forms as well, unless the phrases clearly indicate the opposite. As used herein, the term "comprising" embodies a particular characteristic, region, integer, step, operation, element, and / or component, and other specific characteristics, region, integer, step, operation, element, component, and / or group. It does not exclude the presence or addition of.

Unless defined otherwise, all terms including technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art. Commonly defined terms used are additionally interpreted to have a meaning consistent with the related technical literature and the presently disclosed contents, and are not interpreted in an ideal or very formal sense unless defined.

Embodiments of the invention described with reference to the drawings specifically illustrate an ideal embodiment of the invention. As a result, various variations of the illustration, for example variations in the manufacturing method and / or specification, are expected. Thus, the embodiment is not limited to any particular form of the depicted area, but includes modifications of the form, for example, by manufacture. For example, the regions shown or described as being flat may have characteristics that are generally coarse / rough and nonlinear. Also, the portion shown as having a sharp angle may be rounded. Thus, the regions shown in the figures are merely approximate, and their shapes are not intended to depict the exact shape of the regions, nor are they intended to limit the scope of the present invention.

1 is a schematic cross-sectional view for explaining the configuration as part of a surface light emitting device according to an embodiment of the present invention.

According to the above-described drawings, the apparatus 10 includes a plurality of side light emitting diodes 13 mounted on the front surface of the printed circuit board 12 so that the light emitting surface is directed toward the side surface of the printed circuit board 12, and the side surface thereof. A plurality of reflective structures 20 installed on the printed circuit board 12 to face the light emitting surface of the light emitting diode 13 to reflect the light emitted from the side light emitting diode 13 to the light emitting plane of the front of the device; It includes a reflective sheet 14 attached to the front of the printed circuit board 12. The semistructures may be separately attached to the reflective sheet 14 or integrally formed in the reflective sheet 14.

In the device 10, as described above, the reflective structure 20 and the plurality of side light emitting diodes 13 are organically disposed on the substrate 12 to form one cell 11, and the structure as described above. The cells 11 of 11 may be continuously disposed on the substrate 12 to provide a surface light source having excellent color uniformity and brightness uniformity regardless of the size of the light emitting surface of the device 10.

In the following description, the structure of the cell 11, which is a subunit constituting the apparatus 10, will be described. In addition, in the following description, the side of the substrate refers to the x-axis direction of FIG. 1, and the front surface of the substrate is defined to mean the y-axis direction. In addition, the light emitting surface of the side light emitting diode refers to a surface from which light is emitted from the side light emitting diode, and the light emitting plane of the front surface is defined to mean an actual light emitting surface of the surface light emitting device.

In the present embodiment, the side light emitting diodes 13 have a structure in which the light emitting surface is approximately in the x-axis direction. This does not only mean that the light emitting surface is exactly perpendicular to the light emitting plane so that it faces the x axis.

In addition, the apparatus 10 includes a diffusion sheet 15 or a prism sheet for diffusing light more uniformly or a light sheet for improving brightness (BEF: Dual Brightness Enhancement Film (DBEF) 16). It is provided. The diffusion sheet, the prism sheet, or the optical sheet are alternately stacked on the front side of the printed circuit board 12 to form a front emission plane. In addition, in the present embodiment, a protective sheet 17 for protecting the light emitting plane is further attached to the outermost diffusion sheet 15 forming the light emitting surface plane.

Accordingly, the light emitted from the side light emitting diode 13 in the lateral direction of the substrate 12 is uniformly reflected toward the front surface of the substrate 12 through the reflective structure 20 and the reflective sheet 14 and mixed with each other.

Therefore, although the device 10 is provided with a light emitting diode at a lower portion of the light emitting plane, the side light emitting diode 13 and the reflective structure 20 are used to reflect and mix the light to the front without using a light guide plate. As a result, a uniform surface light source can be obtained and black spots can be prevented due to the concentration of light.

Reference numeral 18, which is not described in FIG. 1, is a reflector guide installed at the outermost end of the substrate 12 to form a sidewall.

In the present exemplary embodiment, the plurality of side light emitting diodes 13 mounted on the substrate 12 may be implemented as a single light emitting diode that realizes white light. As another embodiment for implementing white light, a plurality of red, green, and blue light emitting diodes in addition to the white light emitting diodes may be appropriately disposed on the substrate 12 to realize white light by mixing light emitted from them. .

In addition, the reflective structure 20 is protruded on the substrate as shown in Figure 2 and is made of an elliptical cone shape having a smaller diameter and an elliptical cross-sectional structure toward the top. The side surface of the reflective structure 20 is inclined downward to form a reflective surface 21 for reflecting light to the front surface of the substrate 12.

The angle of inclination of the side reflective surface 21 of the reflective structure 20 is not particularly limited, and may be set to be optimized for refractive index in air by Snell's law.

In addition, the reflective structure 20 has an elliptic cone shape, the side reflective surface 21 has a curved shape. In addition to the curved structure, the reflective surface 21 may be a curved or aspherical surface or a non-planar surface in which the light is totally reflected to the front or neighboring side of the substrate 12.

3 illustrates a structure in which the reflective structure 20 is installed corresponding to the front surface of the light emitting surface of the side light emitting diode 13 according to the present embodiment. As shown in FIG. 3, the reflective structure 20 is installed to face the side light emitting diode 13, and the two side light emitting diodes 13 are disposed to face each other with the reflective structure 20 interposed therebetween. ).

The size of the reflective structure 20 is related to the size of the side light emitting diodes 13, and the size of the reflective light emitting diode 13 to the extent that can totally reflect the light emitted from both sides.

4 illustrates a structure in which the reflective structure 30 has a conical shape as another embodiment of the apparatus. In addition, in the present embodiment, four side light emitting diodes 13 are disposed at the angle of 90 degrees to the reflective structure 30 and the light emitting surface faces the reflective structure to form one cell 11.

This structure is also reflected from the light emitting surface of each side light emitting diode 13 is reflected by the reflecting surface 31 of the reflective structure 30 facing the side light emitting diode 13 and evenly to the front of the substrate 12 Is dispersed.

Meanwhile, FIG. 5 illustrates another embodiment of the reflective structure.

According to FIG. 5, the reflective structure 40 has a straight bar shape and has a trapezoidal cross-sectional shape. Accordingly, both sides of the reflective structure 40 are inclined downward to form a reflective surface 41 for reflecting light to the light emitting plane on the front surface of the substrate 12.

In the present exemplary embodiment, the reflective surface 41 is formed on both sides of the reflective structure 40, but the structure formed on only one side may also be applied.

Accordingly, the side light emitting diodes (see 13 in FIG. 1) are installed so that the light emitting surface faces the reflective surface 41, and a plurality of side light emitting diodes are arranged at intervals along the reflective structure 40 of the straight bar shape.

6 illustrates a cell structure in which a side light emitting diode and a reflective structure are organically coupled according to another embodiment.

According to the above drawings, three pairs of side light emitting diodes 13 are arranged at intervals and each pair of side light emitting diodes 13 are placed so that opposite back sides of the light emitting surface face each other so that each light emitting surface is opposite to each other. It is arranged to face. In addition, a linear bar-shaped reflective structure 40 is disposed in front of the light emitting surface of the side light emitting diode 13 so that light emitted from the light emitting surface is reflected by the reflective surface 41 of the reflective structure 40. .

In addition, according to the present embodiment, the side reflection structure 50 is further provided on both sides of the side surface with respect to the light emitting surface of the side light emitting diode 13 to form a cell 11 structure having a rectangular shape as a whole.

The side reflecting structure 50 is connected to the reflecting structure 40 and has a structure in which the side is inclined downward to form the reflecting surface 51.

Accordingly, the light emitted from the light emitting surface of the side light emitting diode 13 or the light reflected from the reflective structure 40 or the reflective sheet 14 and proceeded to the side reflective structure 50 is also the side reflective structure like the reflective structure 40. Is reflected back to the front emission plane of the substrate 12 and mixed with other light.

7 is another embodiment of a cell structure in which a side light emitting diode and a reflective structure are organically combined.

According to the above drawings, a plurality of side light emitting diodes 13 are provided in one cell 11, and each side light emitting diodes 13 are arranged at intervals so that the light emitting surfaces face the same direction. The front face of the light emitting surface of the diode 13 has a structure in which a reflecting structure 40 having a reflecting surface 41 is arranged.

In addition, according to the present embodiment, the side reflection structure 50 and the rear reflection structure 60 are further installed on the substrate 12 toward both side surfaces and opposite rear surfaces of the light emitting surface of the side light emitting diode 13. The overall structure of the cell 11 is rectangular.

The rear reflection structure 60 is connected to the side reflection structure 50, and also has a structure in which the side is inclined downward to form the reflective surface 61.

Accordingly, a reflective structure is disposed on the entire surface of the side light emitting diodes 13 so that light is reflected from the entire area of the cell 11 to the front light emitting plane of the substrate 12, thereby inducing even more light distribution.

Here, when the cell 11 of the above structure is continuously disposed on the substrate, the back reflection structure of one cell serves as a reflection structure of the next cell. That is, in the cells arranged continuously, the back reflection structure and the reflective structure between neighboring cells are integrally formed to form one body. However, one reflective surface of the rear reflective structure is located at the rear side of the side light emitting diode of one cell to serve as a reflective surface of the rear reflective structure, and the other reflective surface is located at the front of the side light emitting diode of the neighboring cell. It will act as a reflecting surface.

FIG. 8 illustrates a structure in which a plurality of cells are continuously arranged over the entire printed circuit board as another embodiment of the apparatus.

Each cell 11 in the device 10 is an elliptical cone-shaped reflective structure 20, the linear bar-shaped reflective structure 40, the side reflection structure 50 and the rear reflection structure 60 is organically coupled It is structured.

That is, the reflective structure 40, the side reflection structure 50, and the back reflection structure 60 in the form of a straight bar surround the side light emitting diode 13 to form a cell 11 structure having a rectangular shape as a whole. The inner side light emitting diodes 13 are disposed to face the light emitting surface toward the reflective structure, and the reflective structure 20 of the elliptical cone shape is disposed on the front surface of the light emitting surface of each side light emitting diode 13.

Accordingly, the light emitted from the light emitting surface of the side light emitting diode 13 is first reflected by the front surface of the substrate 12 by the reflective structure 20 in the shape of an elliptical cone located directly in front of the light emitting surface, and secondly the outer surface of the cell 11. Reflecting structure 40, the side reflection structure 50 and the back reflection structure 60 to form a reflection to the front of the substrate 12 to increase the light uniformity through a more even light mixing.

9 shows another embodiment of the apparatus.

According to the above drawings, the surface light emitting device 70 includes a plurality of side light emitting diodes 13 mounted on the front surface of the printed circuit board 71 so that the light emitting surface is directed toward the side surface of the printed circuit board 71. It includes a plurality of reflecting structure 72 for reflecting the light emitted from the side light emitting diode 13 to the light emitting plane of the front surface, the reflecting structure 72 is a reflecting surface 73 concavely curved toward the light emitting plane This structure is formed. The printed circuit board 71 is installed on the reflective surface 73 of the reflective structure 72 such that the light emitting surface of the side light emitting diode 13 is inclined at an angle with respect to the light emitting plane to face the bottom of the reflective surface 73. It is structured.

Accordingly, according to the present exemplary embodiment, the light emitting surface of the side light emitting diode 13 is not disposed perpendicular to the light emitting plane but is inclined toward the lower side. Therefore, the light emitted from the light emitting surface of the side emitting photodiode 13 is prevented from proceeding directly to the light emitting plane.

Here, the installation angle of the light emitting plane of the substrate 71 on which the side light emitting diode 13 is mounted is related to the upward divergence angle of light through the light emitting surface of the side light emitting diode 13. Accordingly, the installation angle of the substrate 71 may be set to be equal to or greater than the upward divergence angle of the side light emitting diodes 13.

The reflective structure 72 is installed on the board 74 disposed parallel to the rear surface of the light emitting plane. The board 74 may be a main printed circuit board connected to the printed circuit board 71 or may be a separate supporting member for supporting. In addition, the printed circuit board 71 may have a side light emitting diode 13 continuously mounted at intervals in a linearly extending structure.

The light emitting plane includes a diffusion sheet 15 or a prism sheet for diffusing light more uniformly or a light sheet for improving brightness (BEF: Brightness Enhancement Film, DBEF (16), protective sheet 17). Is further provided. Since this structure has already been described above, a detailed description thereof will be omitted.

With the above structure, light emitted from the light emitting surface of the side light emitting diode 13 is reflected by the concave reflecting surface 73 of the reflecting structure 72 so that the traveling direction of the light is changed upward, that is, toward the light emitting plane.

In this case, since the light emitting surface is inclined downward, the side light emitting diode 13 does not directly radiate light emitted from the light emitting surface of the side light emitting diode 13.

As such, the light emitted from the side light emitting diodes 13 and 13 is reflected to the light emitting plane through the reflecting surface 73 of the reflective structure 72 and mixed with each other in the light emitting plane.

In this way, the light reflected across the entire emission plane is evenly mixed with each other to obtain a surface light source having excellent light uniformity.

10 shows another embodiment of the apparatus.

According to the above drawings, the surface light emitting device includes a plurality of side light emitting diodes 13 mounted on the front surface of the printed circuit board 81 so that the light emitting surface is directed toward the side surface of the printed circuit board 81, and the side light emitting diodes. A plurality of reflecting structures for reflecting light emitted from (13) to a light emitting plane of the front face, the reflecting structure including a board 82 disposed parallel to the light emitting plane and having a front face of the reflecting face 83; The printed circuit board 81 is inclined at an angle to the board 82 so that the light emitting surface of the side light emitting diode 13 is inclined at the reflective surface 83 of the board 82.

Accordingly, according to the present exemplary embodiment, the light emitting surface of the side light emitting diode 13 is not disposed perpendicular to the light emitting plane but is inclined toward the lower side. Therefore, the light emitted from the light emitting surface of the side light emitting diode 13 is prevented from proceeding directly to the light emitting plane.

Here, the installation angle of the light emitting plane of the substrate 81 on which the side light emitting diodes 13 are mounted is related to the upward divergence angle of light through the light emitting surface of the side light emitting diodes 13. Accordingly, the installation angle of the substrate 81 may be set to be equal to or greater than the upward divergence angle of the side light emitting diodes 13.

In addition, a light dispersing lens 84 for dispersing light emitted from the side light emitting diode 13 is further provided on the reflective surface of the board 82.

The board 82 may be a main printed circuit board connected to the printed circuit board 81 or a separate supporting member. In addition, the printed circuit board 81 may have the side light emitting diodes 13 continuously mounted at intervals in a linearly extending structure.

The light emitting plane includes a diffusion sheet 15 or a prism sheet for diffusing light more uniformly or a light sheet for improving brightness (BEF: Brightness Enhancement Film, DBEF (16), protective sheet 17). Is further provided. Since this structure has already been described above, a detailed description thereof will be omitted.

With the above structure, the light emitted from the light emitting surface of the side light emitting diode 13 is inclinedly irradiated to the reflecting surface 83 of the board 82. The light irradiated obliquely is reflected by the reflecting surface 83 so that the traveling direction of the light is turned upward, that is, toward the light emitting plane. The light dispersing lens 84 provided on the reflective surface disperses the light emitted from the side light emitting diode 13 to minimize the concentration of light.

In this case, since the light emitting surface is inclined downward, the side light emitting diode 13 does not directly radiate light emitted from the light emitting surface of the side light emitting diode 13.

As such, the light emitted from the side light emitting diode 13 is reflected to the light emitting plane through the reflecting surface 83 of the board 82, which is a reflective structure, and mixed with each other in the light emitting plane.

In this way, the light reflected across the entire emission plane is evenly mixed with each other to obtain a surface light source having excellent light uniformity.

Figure 11 shows another embodiment of the apparatus.

According to the above-described drawings, the surface light emitting device includes a plurality of side light emitting diodes 13 mounted on the front surface of the printed circuit board 91 so that the light emitting surface faces the side of the printed circuit board 91, and the side light emitting diodes ( 13 includes a plurality of reflective structures for reflecting light emitted from the light emitting surface of the front surface, wherein the reflective structures are made of a reflective sheet 92 attached on a substrate 91 and the reflective sheet 92 Is inclined upward from the substrate 91 to form the reflective surface 93.

According to the present exemplary embodiment, a plurality of the side light emitting diodes 13 may be disposed at intervals, and the reflective sheet 92 may have a structure covering the top surface of the light emitting diodes 13 adjacent to the front end thereof. That is, the reflective sheet 92 forms the reflective surface 93 starting from the lower side of the light emitting diode 13 so that the inclined reflective surface 93 is located immediately before the light emitting surface of the side light emitting diode 13. The tip has a structure extending to the upper end of the next side light emitting diode 13.

In addition, the light emitting plane is a diffusion sheet 15 or a prism sheet for diffusing light more uniformly or a light sheet for improving brightness (BEF: Brightness Enhancement Film, DBEF: Dual Brightness Enhancement Film (16), protective sheet ( 17) is further provided. Since this structure has already been described above, a detailed description thereof will be omitted.

With the above structure, the light emitted from the light emitting surface of the side light emitting diode 13 is reflected by the reflecting surface 93 of the reflecting sheet 92 which is inclined with respect to the light emitting surface, so that the direction of light travels upward. Switch to the plane.

The light reflected from the reflective surface 93 of the reflective sheet 92 to the light emitting plane is mixed and mixed with each other in the light emitting plane.

In this way, by reflecting the light emitted from the side light emitting diode 13, the light reflected across the entire light emitting plane is evenly mixed with each other to obtain a surface light source with excellent light uniformity.

Hereinafter, the operation of the apparatus will be described with reference to the cell structure according to the embodiment of FIG. 1.

This device 10 is a device that can reflect the light emitted from the side light emitting diode 13 to the side of the substrate to the entire surface of the substrate to obtain a surface light emission having a low thickness and excellent light uniformity.

That is, light emitted from the light emitting surface of the side light emitting diode 13 is emitted in the x-axis direction, which is the side surface of the substrate 12.

The light emitted in this way is not directly irradiated to the front emission plane of the substrate 12 except for a part of the light and is spread in the lateral direction of the substrate 12.

Some of the light spread in the lateral direction of the substrate 12 is reflected by the inclined reflecting surface 21 of the reflecting structure 20 disposed in front of the light emitting surface of the side light emitting diode 13, so that the traveling direction is upward. , The front side of the substrate 12 is switched. In this case, the reflective structure 20 has an elliptical cone-shaped curved surface to diffuse and reflect light at a wider radiation angle.

Further, of the light emitted from the light emitting surface of the side light emitting diode 13, the light propagated toward the bottom of the substrate 12 is reflected by the reflective sheet 14 attached to the bottom of the substrate 12 so that the front surface of the substrate 12 is exposed. And part of the light is reflected by the reflective structure 20 to face the front surface of the substrate 12.

The light emitted from the side light emitting diodes 13 to the side is converted to the front direction of the substrate 12 through the reflective structure 20 and the reflective sheet 14 so that they are mixed and mixed with each other on the front surface of the substrate 12. do.

In this way, the light reflected on the entire light emitting plane of the entire surface of the substrate 12 is evenly mixed with each other to obtain a surface light source having excellent light uniformity.

The mixed light as described above passes through the diffusion sheet 15 and the light sheet 16 provided on the substrate 12 at a predetermined height, thereby increasing color and brightness uniformity.

In addition, the apparatus reflects the light emitted through the side light emitting diode 13 to have a wide directing angle so that the light is evenly mixed directly above the side light emitting diode 13 so that the light emitting source side light emitting diode 13 and the substrate 12 are provided. Even if the distance between the front light emitting plane is reduced as much as possible, it is possible to obtain a uniform surface light source in which a phenomenon such as black spot generation does not occur.

Therefore, when using the device, it is possible to obtain a lighter having a thinner structure or a backlight unit of the liquid crystal device.

FIG. 12 is a graph showing a light distribution on a plane implemented by the surface light emitting device according to the present embodiment and the prior art, in which particles receiving light for the same area are indicated by dots.

In the prior art, it can be seen that the light is concentrated in the center. On the contrary, the surface light emitting device having the side light emitting diode and the reflective structure as shown in the present embodiment can realize the light source having a wide light distribution and uniformity. Two graphs according to the present embodiment are shown, one of which is a light distribution graph of the structure in which the reflective structure protrudes on the substrate and the other is a light distribution graph of the structure in which the reflective sheet is inclined on the substrate. to be. In the graphs according to the two embodiments of the present invention, the light distribution is very similar to each other, and thus a light source having a wide light distribution and a uniform light distribution can be realized in both the structure in which the reflective structure protrudes or the reflective sheet is inclined. It can be seen that.

Although the preferred embodiments of the present invention have been described above, the present invention is not limited thereto, and various modifications and changes can be made within the scope of the claims and the detailed description of the invention and the accompanying drawings. Naturally, it belongs to the range of.

1 is a cross-sectional view showing a schematic configuration of a surface light emitting device according to an embodiment of the present invention.

2 is a perspective view showing a reflective structure of a surface light emitting device according to an embodiment of the present invention.

3 is a schematic plan view showing an installation structure of a reflective structure and a light emitting diode according to an embodiment of the present invention.

4 is a schematic plan view illustrating a reflective structure and an installation structure of a light emitting diode according to another embodiment of the present invention.

5 is a perspective view showing another embodiment of a reflective structure of a surface light emitting device according to another embodiment of the present invention.

6 is a schematic plan view of a surface light emitting device according to still another embodiment of the present invention.

7 is a schematic plan view of a surface light emitting device according to another embodiment of the present invention.

8 is a schematic plan view of a surface light emitting device according to another embodiment of the present invention.

9 is a cross-sectional view showing a schematic configuration of a surface light emitting device according to another embodiment of the present invention.

10 is a cross-sectional view illustrating a schematic configuration of a surface light emitting device according to another embodiment of the present invention.

11 is a cross-sectional view showing a schematic configuration of a surface light emitting device according to another embodiment of the present invention.

12 is a graph illustrating a comparison of light distribution of a light emitting surface implemented by an embodiment of the present invention and a surface light emitting device according to the related art.

Explanation of symbols on the main parts of the drawings

11 cell 12 printed circuit board

13: side light emitting diode 14: reflective sheet

15: diffusion sheet 20, 30, 40: reflective structure

21,31,41,51,61: Reflective surface 50: Side reflection structure

60: rear reflection structure

Claims (13)

A plurality of light emitting diodes disposed on the substrate and mounted so that the light emitting surface faces the substrate side; One or more reflective structures, The reflective structure includes a board parallel to the light emitting plane and a reflecting surface is formed on the front surface, wherein the light emitting diode is a light emitting surface is installed obliquely toward the reflecting surface, the light emitting lens is provided on the reflecting surface. delete delete delete delete delete delete delete delete delete delete delete delete

Images