KR20140069823A - Lighting apparatus - Google Patents

Abstract

More particularly, the present invention provides a diffusion layer having a predetermined refractive index and thickness between a diffusion member and a light control layer selectively transmitting the emitted light of the LED. As the emitted light of the LED diffuses through the diffusion layer, the emitted light of the LED can be uniformly emitted from the front surface of the diffusion member.

Description

[0001]

The present invention relates to a lighting apparatus, and more particularly, to a lighting apparatus capable of improving uniformity of illumination.

Conventionally, lighting devices such as incandescent lamps, fluorescent lamps, and halogen lamps have been widely used to provide a lighting effect to the surrounding environment.

In recent years, the use of a lighting device using a light emitting diode as a light source instead of a conventional filament type, a fluorescent bulb, or a halogen lamp is gradually increasing. That is, the light emitting diode is directly used to serve as a general lighting for a home or an office.

Generally, a light emitting diode generates a small number of injected carriers (electrons or holes) by using a p-n junction structure of a semiconductor, and emits light by recombination of these carriers. LEDs are smaller in size than conventional light sources, have a long life span, and have low power and efficiency because electric energy is directly converted into light energy. It is also used for display lamps of various electronic devices such as display devices of automobile instruments and light sources for optical communication due to high-speed response, card readers of numeric display devices and calculators.

LED lamps, LED downlights, LED flat lights, LED tubes, LED sine channels, LED light bars, etc. are collectively referred to as LED lighting fixtures or LED lighting fixtures. do.

As described above, the type of LED, the arrangement of LEDs, the number of LEDs, brightness of required illumination, and the like can be applied to LED lighting apparatuses differently according to the environment in which they are used. When it is used for indoor illumination, it is required to uniformly provide the emitted light of the cosmetic LED in the room.

In the case of conventional LED flat panel illumination, a diffusion member is provided on the case front surface of the illumination device for uniform diffusion of emitted light, and a plurality of optical films are provided between the diffusion member and the LED.

Accordingly, hot spots of the LED light source can be removed and the uniformity of the illumination can be improved. However, the production cost of the illumination device is increased due to the multiple layers of the optical film, and the manufacturing process is complicated.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems, and an object of the present invention is to provide a lighting system capable of improving the uniformity of illumination by removing hot spots caused by a light source, Device.

According to an aspect of the present invention, there is provided an illumination device including a case, a light emitting unit including a circuit board provided in the case and a plurality of LEDs mounted on the circuit board, A light guiding member provided on the circuit board for guiding light emitted from the LED, and a reflection pattern provided on the light guiding member for reflecting light emitted from the LED into the light guiding member, A diffusion member including a light transmission portion for emitting light having passed through the light guide member to the outside and a mounting portion extending from the light transmission portion toward the light emitting unit and mounted on the case; And a diffusion layer provided between the member and the light control layer and having a predetermined refractive index and thickness .

The present invention is characterized in that the thickness (W) of the diffusion layer is in the range of 3.5 mm? W? 5.5 mm.

Further, the present invention is characterized in that the thickness (Td) of the diffusion member is in the range of 1 mm? Td? 1.5 mm.

In addition, the present invention is characterized in that the thickness (Tc) of the light control layer is in the range of 0.1 mm? Tg? 0.3 mm.

Further, the present invention is characterized in that the thickness (Tg) of the light guide member is in the range of 0.8 mm? Tg? 2 mm.

Further, the thickness ratio of the diffusion member to the diffusion layer is in the range of 1: 3.5 to 1: 5.5.

Further, in the present invention, the thickness of the diffusion layer is a vertical distance between mutually facing surfaces (surfaces) of the light control layer and the light transmitting portion.

In addition, the present invention is characterized in that the mounting portion is extended so that an end thereof is in contact with the light control layer, thereby separating the light transmitting portion from the light control layer.

The present invention is characterized in that the diffusion layer is an air layer having a refractive index of 1, which is filled in a spaced space between the diffusion member and the light control layer.

In addition, the present invention is characterized in that a protruded engaging portion is provided on the inner surface of the case, and a groove portion into which the engaging portion is inserted is provided in the mounting portion.

Further, the present invention is characterized in that the case includes an upper open area, and the diffusion member is mounted to the case to shield the open area.

In addition, the present invention is characterized in that the circuit board includes a reflecting member which reflects the emitted light reflected by the reflection pattern.

Further, the present invention is characterized in that emitted light is emitted from the side of the LED.

According to the present invention, a diffusion layer having a predetermined width is provided between the light emitting unit and the diffusion member by the mounting portion of the diffusion member, and the predetermined thickness W is in the range of 3.5 mm? W? .

In addition, according to the present invention, the thickness Td of the diffusion member is in the range of 1 mm? Td? 1.5 mm in the range of the predetermined thickness W, thereby preventing the overall thickness from being excessively increased while increasing the uniformity of the lighting apparatus .

In addition, according to the present invention, emitted light is emitted from the side surface of the light source, and concentration of the emitted light in a specific area of the illumination device can be suppressed.

1 is an exploded perspective view of a lighting apparatus according to an embodiment of the present invention.
2 is a perspective view illustrating a lighting apparatus connected to a ceiling and a cable according to an embodiment of the present invention.
3 is a cross-sectional view of a lighting apparatus according to an embodiment of the present invention.
4 is a conceptual diagram illustrating a state in which emitted light is diffused in the illumination device according to an embodiment of the present invention.
5 (a) is a plan view of the illumination device, and FIG. 5 (b) is a brightness-distance graph showing the brightness of illumination of A-A 'shown in FIG. 5 (a).
6 is a conceptual diagram illustrating movement of emitted light within a light guide member according to an embodiment of the present invention.
7 is a cross-sectional view of a lighting apparatus according to another embodiment of the present invention.

Hereinafter, a lighting apparatus according to an embodiment of the present invention will be described in detail with reference to the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS The accompanying drawings, which are included to provide a further understanding of the invention and are incorporated in and constitute a part of this application, illustrate embodiments of the invention and, together with the description, serve to explain the principles of the invention.

In addition, the same or corresponding components are denoted by the same reference numerals regardless of the reference numerals, and redundant description thereof will be omitted. For convenience of explanation, the size and shape of each constituent member shown may be exaggerated or reduced have.

1 is an exploded perspective view of a lighting apparatus according to an embodiment of the present invention. 2 is a perspective view illustrating a lighting apparatus connected to a ceiling and a cable according to an embodiment of the present invention.

A light emitting unit 140 including a plurality of LEDs 142 mounted on a circuit board 141 and a circuit board 141 provided inside the case 110; A light guiding member 143 provided on the circuit board 141 to surround the light guide member 142 and guiding the light emitted from the LED 142 and a light guide member 143 provided on the light guide member 143, A light control layer 146 including a reflection pattern 147 for reflecting light into the light guide member 143 and a light transmission portion 120 for emitting light having passed through the light guide member 143 to the outside, And a diffusion member D extending from the light transmitting portion 120 toward the light emitting unit 140 and including a mounting portion 130 mounted on the case 110. [

The case 110 forms the appearance of the lighting apparatus and may be plate-shaped. The case 110 includes an open area at the top, and a diffusion member D is mounted in the open area. That is, the open region of the case 110 can be shielded by the diffusion member D.

In addition, the case 110 includes a coupling portion 112 on the inner side surface 113 thereof. The engaging portion 112 may have a shape protruding from the side surface 113 inside the case 110. The coupling portion 112 serves to couple the diffusion member D to the case 110.

The cover 160 may be coupled to the side surface 113 of the case 110. The cover 160 is engaged to shield the open side 113 of the case 110. The cover 160 can be fastened to the fastening hole of the bottom surface 114 of the case 110 through a screw.

The light emitting unit 140 is provided inside the case 110. Specifically, the light emitting unit 140 is located on the bottom surface 114 inside the case 110. The light emitting unit 140 may include a circuit board 141 and a plurality of LEDs 142 mounted on the circuit board 141.

On the other hand, it is preferable to use an LED (Light Emitting Diode) 142 as a light source, but not limited thereto, and an OLED (Organic Light Emitting Diode)

The light guide member 143 is provided on the circuit board 141 to surround the plurality of LEDs 142. The light guide member 143 is provided on the circuit board 141 and a receiving groove 144 in which the LED 142 is located is provided in the light guide member 143. The light guide member 143 guides the emitted light emitted from the LED 142 to be uniformly incident on the front surface of the case 110.

The light control layer 146 is provided on the upper surface of the light guide member 143. The light control layer 146 includes a reflective pattern 147 to reflect some of the emitted light of the LED 142. That is, the light control layer 146 reflects the emitted light incident on the reflection pattern 147 and transmits the light incident on the surrounding area surrounding the reflection pattern 147. The movement path of the emitted light of the LED 142 in the light emitting unit 140 will be described later in detail.

The diffusion member D includes a light transmitting portion 120 and a mounting portion 130. The diffusion member D is mounted on the front surface of the case 110 to scatter and disperse the emitted light of the LED 142 passing through the light control layer 146. The emitted light is scattered while passing through the diffusion member D and can be uniformly emitted to the outside from the front surface of the diffusion member D. [

On the other hand, the mounting portion 130 is provided on the back surface of the light transmitting portion 120. The mounting portion 130 is spaced apart from each other such that a diffusion layer S (see FIG. 3) having a predetermined refractive index and thickness is provided between the diffusion member D and the light control layer 146. Specifically, the mounting portion 130 separates the light transmitting portion 120 and the light control layer 146 to have a predetermined thickness.

The mounting portion 130 may be engaged with the coupling portion 112 to couple the diffusion member D to the case 110. [

2, the present invention further includes a power supply device P attached to a ceiling of a room. The case 110 is connected to the power supply device P by a cable W, Can be spaced apart. The cable W can be electrically connected to the circuit board 141 to supply power to the lighting apparatus.

FIG. 3 is a cross-sectional view of a lighting apparatus according to an embodiment of the present invention, and FIG. 4 is a conceptual diagram illustrating a state in which emitted light is diffused in an illumination apparatus according to an embodiment of the present invention. Hereinafter, with reference to the drawings, a description will be given of a diffusion layer in an illumination device provided for uniform illumination.

The present invention can separate the light transmitting portion 120 and the light control layer 146 from each other through the mounting portion 130. A diffusion layer S having a predetermined thickness W is provided between the light transmission portion 120 and the light control layer 146 by the mounting portion 130. [ The emitted light of the LED 142 sequentially passes through the light guide member 143, the light control layer 146 and the diffusion layer S and is incident on the diffusion member D.

In one embodiment, the mounting portion 130 may be provided on both sides of the rear surface of the light transmitting portion 120. The mounting portion 130 may include a body portion 131 and a groove portion 133 provided in the body portion 131. [

The body portion 131 extends in a direction perpendicular to the back surface of the light transmitting portion 120. The body portion 131 is extended so that the end of the body portion 131 is in contact with the light control layer 146. Accordingly, the body 131 can separate the diffusion member D and the light control layer 146 from each other by a predetermined thickness W. [

The body part 131 may fix the light emitting unit 140 and the circuit board 141 inside the case 110 by closely contacting the light emitting unit 140 to the bottom surface 114 of the case 110 . The body portion 131 may be extended so that its end is in contact with the light control layer 146 so that the circuit board 141 is brought into close contact with the bottom surface 114 of the case 110. [ On the other hand, the engaging portion 112 is inserted into the groove 133.

Here, the predetermined thickness W is a vertical distance between mutually opposing surfaces of the light control layer 146 and the light transmitting portion 120. The vertical distance between the upper surface of the light control layer 146 and the lower surface of the light transmitting portion 120 is referred to as a preset thickness W. [

The diffusion layer S of the present invention may be an air layer having a refractive index of 1 filled in a spaced space between the light transmitting portion 120 and the light control layer 146. [ That is, an empty space may be provided between the light transmitting portion 120 and the light control layer 146 to fill the air.

Accordingly, the emitted light can be uniformly incident on the diffusion member D while passing through the diffusion layer S in the case 110. Specifically, the emission angle [theta] formed by the light emitted from the light control layer 146 and the upper surface of the light control layer 146 is in the range of 0 [deg.] ≪ The emitted light advances in the emission angle direction and passes through the diffusion layer S. [

That is, the larger the thickness W of the diffusion layer S, the farther the emission light travels along the emission angle from the upper surface point of the light control layer 146 through which the emission light has passed, I will join. Therefore, the emitted light is concentrated in the region of the diffusion member D adjacent to the LED 142, and hot spots are prevented from being generated, and the uniformity of illumination can be increased.

As described above, the thickness W of the diffusion layer S is an important factor determining the degree of diffusion of the emitted light. When the thickness W of the diffusion layer S is narrow, a sufficient distance for the emission light to proceed can not be ensured and the uniformity of illumination is reduced. On the contrary, when the thickness W of the diffusion layer S is large, there is a problem that the uniformity of illumination is high but the size of the illumination device is large and the brightness is low.

The present invention has resulted in the following optimum ranges for ensuring high uniformity of illumination while reducing the size of the lighting apparatus through repeated experiments.

The predetermined thickness (W) of the diffusion layer (S) according to the present invention is in the range of 3.5 mm? W? 5.5 mm. A hot spot is clearly generated when the difference in brightness between the area adjacent to the LED 142 on the front surface of the diffusion member D and the remaining area is 10% or more, and in the case of 5% to 10%, a sensitive person can recognize the hot spot have. In the present invention, the brightness difference of the illumination is less than 5% in the predetermined thickness (W) range, the hot spot can be removed, the uniformity of the illumination can be ensured, and the size of the illumination device can be minimized.

At this time, the thickness Td of the diffusion member D is in the range of 1 mm? Td? 1.5 mm. Here, the thickness of the diffusion member (D) refers to the thickness of the light transmitting portion (120). When the diffusion member D is thin, it is difficult to secure the strength. When the diffusion member D is thick, there is a problem that the emitted light is absorbed and blocked. By forming the diffusion member (D) within the above-mentioned thickness range, it is possible to prevent the brightness of emission light from being lowered simultaneously with securing the strength.

The thickness ratio of the diffusion member D to the diffusion layer S may be in the range of 1: 3.5 to 1: 5.5. Here, the thickness of the diffusion member (D) refers to the thickness of the light transmitting portion (120).

The thickness Tg of the light guide member 143 is in the range of 0.8 mm? Tg? 2 mm. Since the LED 142 is located inside the light guide member 143, the thickness Tp of the LED 142 may be in the range of 0.5 mm? Tp? 1.8 mm, which is smaller than the thickness of the light guide member 143. That is, the light guide member 143 is formed to be at least 2 mm thicker than the thickness of the LED 142, thereby preventing defects due to the error of the normal light guide member 143 and slimming the illumination device.

The thickness Tc of the light control layer 146 is in the range of 0.1 mm < / = Tg ≤ 0.3 mm. The thickness of the light control layer 146 in the thickness range can be made flexible so that sufficient strength can be ensured and the thickness can be reduced.

As shown in Fig. 4 (a), the brightness of illumination was continuously measured along the area indicated by the line A-A 'in the front surface of the diffusion member (D) of the illumination device having the numerical range described above. Here, the center point O 'is a region of the diffusion member D in which the LED 142 is located at the lower portion, and has the largest brightness.

4 (b) is a brightness-distance graph of the area indicated by line A-A '. The vertical axis of the graph represents the relative brightness ratio when the largest brightness of the center point (O ') region is 100%. In the present invention, the brightness difference of the illumination in the area indicated by the line A-A 'within the numerical range is within 2.5%. That is, when the brightness of the brightest region is 100%, the brightness of the darkest region is 97.5%.

As described above, the present invention can improve the uniformity of illumination, and can omit a separate optical film structure, thereby saving manufacturing cost. Further, since the step of attaching the optical film is not required, the manufacturing process of the lighting apparatus is simplified. In addition, the illuminating device can be made slimmer by minimizing the thickness increase of the illuminating device.

Further, the present invention can emit emitted light on the side of the LED 142. [ The LED 142 may be of a direct type that directly emits the emitted light toward the front surface of the case 110 and a direct type that emits light from the side surface of the LED 142, An edge type method of guiding emitted light can be used. The edge type method can prevent the emission light from concentrating on a specific area and can increase the uniformity compared with the direct type method.

Hereinafter, referring again to FIG. 3, the structure of the case and the diffusion member of the present invention will be described.

The coupling part 112 of the case 110 and the mounting part 130 of the back surface of the light transmitting part 120 are combined with each other so that the diffusion member D can be coupled to the case 110. [ Specifically, the engaging portion 112 protruding from the side surface 113 of the case 110 is inserted into the groove portion 133 of the mounting portion 130, so that the engaging portion 112 and the mounting portion 130 can be coupled with each other .

Accordingly, the present invention can reduce the lateral width L of the illumination device, as compared with the structure in which the side of the conventional diffusion member D and the side surface of the case 110 are joined. Since the coupling structure between the engaging portion 112 of the case 110 and the mounting portion 130 is located on the back surface of the light transmitting portion 120, an increase in the lateral width L of the lighting device due to the coupling structure There is no.

Meanwhile, the engaging portion 112 may have a shape extending along the side surface 113 inside the case 110. The groove portion 133 is provided on a side surface of the body portion 131 in a shape corresponding to the engaging portion 112. The engaging portion 112 may extend integrally along the side surface 113 or may be divided into a plurality of unit engaging portions 112 including an intermediate portion.

Meanwhile, the diffusion member D and the mounting portion 130 may be integrally formed. The diffusion member (D) and the mounting portion (130) can be integrally formed of the same light diffusion material, thereby simplifying the manufacturing process.

Some of the emitted light of the LED 142 may be bent outward while passing through the mounting portion 130 and may be incident on the diffusion member D. [ The outwardly curved emitted light is incident on the back surface of both sides of the light transmitting portion 120, so that the emitted light can be emitted from the exposed front surface of the diffusion member D.

6 is a conceptual diagram illustrating movement of emitted light within a light guide member according to an embodiment of the present invention. Hereinafter, the indoor lighting process of the light emitted from the light source of the present invention will be described in detail.

The light guide member 143 includes a resin layer 145 on which the receiving groove 144 is formed. The light control layer 146 is provided on the upper surface of the resin layer 145. The reflection pattern 147 of the light control layer 146 reflects the emitted light passing through the resin layer 145 in a direction opposite to the incident direction.

That is, the light emitted from the side surface of the LED 142 in the direction of the diffusion member D is reflected by the reflection pattern 147 in the direction opposite to the incident direction, and then enters the resin layer 145 again.

At this time, the circuit board 141 may be provided with a reflection member 150 that reflects the incident light reflected by the reflection pattern 147 in the opposite direction. The reflective member 150 is formed on the upper surface of the circuit board 141 and is positioned between the resin layer 145 and the circuit board 141.

The emitted light is reflected again by the reflecting member 150, so that the emitted light proceeds to the inside of the resin layer 145. The emitted light proceeding between the reflection patterns 147 of the emitted reflected light passes through the light guide member 143 and enters the diffusion member D, thereby illuminating the room. The emitted light incident on the reflection pattern 147 is reflected again and proceeds inside the resin layer 145.

The reflective member 150 may be a plurality of scratches or a plurality of dots.

As described above, since the emitted light is incident on the diffusion member D in a state in which the distance from the LED 142 is distant due to repetitive reflection of the light control layer 146 and the reflection member 150, .

On the other hand, the number or the area of reflection of the reflective member 150 may gradually decrease as the distance from the LED 142 increases. The closer the LED 142 is to the LED 142, the higher the density of the emitted light, and the greater the necessity of dispersing the emitted light.

7 is a cross-sectional view of a lighting apparatus according to another embodiment of the present invention. Hereinafter, another embodiment of the present invention will be described with reference to the drawings. Duplicate contents of the above description will be omitted or briefly explained.

The light source 230 includes a case 210 having a front face opened, a diffusion member 220 provided on an open front face of the case 210, a plurality of light sources 230 provided inside the case 210, A light guide member 255 provided on the upper surface of the light guide member 255 for guiding emitted light so that the emitted light of the light guide layer 255 is uniformly incident on the entire surface of the case 210, ).

A diffusion layer S having a predetermined thickness W is provided between the light control layer 253 and the diffusion member 220 in the case 210. [ Here, the predetermined thickness W is a vertical distance between mutually opposing surfaces of the light control layer 253 and the diffusion member 220.

As described above, the light emitted from the light source can be uniformly incident on the diffusion member 220 while passing through the diffusion layer S in the case 210. Therefore, the emitted light is concentrated on the region of the diffusion member 220 adjacent to the light source 230 to prevent hot spots from being generated, and the uniformity of illumination can be increased.

At this time, the preset thickness (W) is in the range of 3.5 mm ≤ W ≤ 5.5 mm. The brightness difference of the illumination in the predetermined thickness (W) range is less than 5%, the hot spot can be removed, the uniformity of illumination can be ensured and the size of the illumination device can be minimized.

The thickness Td of the diffusion member 220 is in the range of 1 mm? Td? 1.5 mm. It is possible to prevent the brightness of the illumination from decreasing at the same time as securing the strength of the diffusion member 220 in the thickness range of the diffusion member.

The thickness Tg of the light guide member 255 is in the range of 0.8 mm? Tg? 2 mm and the thickness Tp of the light source 230 may be in the range of 0.5 mm? Tp? 1.8 mm. The light guide member 255 may be formed to have a thickness of at least 2 mm larger than the thickness of the light source 230 to prevent a defect due to an error of the normal light guide member 255 and to make the lighting apparatus slimmer.

The thickness Tc of the light control layer 253 is in the range of 0.1 mm? Tg? 0.3 mm. The thickness of the light control layer 253 in the above-mentioned thickness range can be made flexible so as to secure sufficient strength and to be slim.

The light guide member 255 includes a resin layer 252 provided on the circuit board 240 inside the case 210 and a receiving groove 251 provided in the resin layer 252. The light source 230 may be located inside the receiving groove 251 and may be electrically connected to the circuit board 240.

The light control layer 253 includes a reflection pattern 254 provided on the upper surface of the resin layer 252 and reflecting the light in a direction opposite to the direction of incidence of the emitted light. In addition, the circuit board 240 may include a reflective member 260 that reflects the incident light reflected by the reflective pattern 254 in the opposite direction.

The foregoing description of the preferred embodiments of the present invention has been presented for purposes of illustration and various modifications, additions and substitutions are possible, without departing from the scope and spirit of the invention, And additions should be considered as falling within the scope of the following claims.

110, 210: Case 120: Light transmitting portion
130: mounting portion 131:
133: groove portion 140: light emitting unit
141, 240: circuit board 142, 230: light source
143, 255: light guide member 144, 251: receiving groove
145, 252: resin layer 146, 253: light control layer
147, 254: reflection pattern 150, 260: reflection member
D: diffusion member

Claims (13)

case;
A light emitting unit including a circuit board provided inside the case and a plurality of LEDs mounted on the circuit board;
A light guiding member provided on the circuit board to surround the plurality of LEDs and guiding light emitted from the LEDs;
A light control layer provided on the light guide member and including a reflection pattern for reflecting the light emitted from the LED into the light guide member;
A diffusion member including a light transmitting portion for emitting light having passed through the light guide member to the outside and a mounting portion extending from the light transmitting portion toward the light emitting unit and mounted to the case; And
And a diffusion layer provided between the diffusion member and the light control layer and having a predetermined refractive index and thickness. The method according to claim 1,
And the thickness (W) of the diffusion layer is in the range of 3.5 mm? W? 5.5 mm. 3. The method of claim 2,
And the thickness Td of the diffusion member is in the range of 1 mm? Td? 1.5 mm. 3. The method of claim 2,
Wherein a thickness (Tc) of the light control layer is in the range of 0.1 mm < = Tg < = 0.3 mm. 3. The method of claim 2,
And the thickness Tg of the light guide member is in the range of 0.8 mm? Tg? 2 mm. The method according to claim 1,
Wherein the thickness ratio of the diffusion member to the diffusion layer is in the range of 1: 3.5 to 1: 5.5. The method according to claim 1,
Wherein the thickness of the diffusion layer is a vertical distance between mutually opposing surfaces of the light control layer and the light transmission portion. The method according to claim 1,
Wherein the mounting portion extends so that an end thereof is in contact with the light control layer, thereby separating the light transmitting portion from the light control layer. 9. The method of claim 8,
Wherein the diffusion layer is an air layer having a refractive index of 1, which is filled in a spaced-apart space between the light transmission portion and the light control layer. The method according to claim 1,
A protruded engaging portion is provided on an inner side surface of the case,
Wherein the mounting portion is provided with a groove into which the engaging portion is inserted. The method according to claim 1,
The case includes a top open area,
Wherein the diffusion member is mounted to the case to shield the open area. The method according to claim 1,
Wherein the circuit board includes a reflecting member that reflects the incident light reflected by the reflection pattern. The method according to claim 1,
Wherein the LED emits emission light on its side.

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