Planar light source device

Abstract

An embodiment of the present invention may provide a planar light source device comprising: a PCB having a circuit wiring formed therein; multiple LED light sources mounted on the PCB to emit light from the top and side surfaces thereof; and a transparent resin layer in which the multiple LED light sources are embedded, the resin layer guiding the light emitted from the LED light sources and emitting the light through one surface thereof.

Description

Planar Light Source Device

[0001] The present invention relates to a surface light source device, and more particularly, to a surface light source device including a plurality of LED light sources that emit light to the upper and side surfaces and a transparent resin layer to improve the luminance distribution of a light-emitting surface when using an LED light source that is a point light source.

[0002]

[0003] Typically, automobiles are equipped with various lighting devices at the front and rear to ensure vehicle safety and driving convenience. These lighting devices include headlights, taillights, and turn signals that operate by directly emitting light using lamps. In addition, reflectors are installed at the front and rear of the automobile to reflect light so that the automobile can be easily recognized from the outside. These lighting devices use various types of light sources due to recent technological advancements. In the past, lighting devices using general light bulbs evolved into lighting devices using LEDs. However, even when using LEDs, there were limitations in making the lighting devices slimmer due to the presence of light guides on the sides of the light source that reflected the light. Therefore, there is a need for the development of automotive lighting devices that are thinner, utilize the automobile's space efficiently, and are advantageous in terms of design.

[0004]

[0005] Prior literature: Korean Patent No. 10-1253987

[0006] The prior art document relates to a 'light guide plate for a surface light source device and a backlight unit using the same', and relates to a light guide plate for a surface light source device and a backlight unit using the same, which not only has high frontal brightness by increasing the light efficiency in the backlight, but also has a wide viewing angle and excellent brightness uniformity. To this end, the prior art document relates to a light guide plate including an incident surface on which light is incident from a light source arranged along an axis, an exit surface on which the incident light is emitted, and a back surface facing the exit surface, wherein a lenticular, prism, or microlens shape is formed on the exit surface, and a plurality of unit cells having a microprism pattern engraved thereon are dispersedly arranged on the back surface, wherein the unit prism ridges of the microprism patterns are curved, and the direction in which the ridges advance is parallel to the direction in which the light sources are arranged.

[0007] In this way, various studies are being conducted on the arrangement of internal components and manufacturing processes to improve light uniformity and increase light efficiency in surface light sources.

[0008]

[0009]

[0010] One embodiment of the present invention can provide a surface light source device including a plurality of LED light sources that emit light to the upper and side surfaces and a transparent resin layer to improve the light brightness distribution of the light emission surface when using an LED light source that is a point light source.

[0011]

[0012] One embodiment of the present invention can provide a surface light source device including a PCB substrate having circuit wiring formed therein, a plurality of LED light sources mounted on the PCB substrate and emitting light to the upper surface and side surfaces, and a transparent resin layer embedding the plurality of LED light sources and guiding light output from the LED light sources to output light to one surface.

[0013] The above surface light source device may further include a diffusion agent powder dispersed within the transparent resin layer.

[0014] The LED light source may include a lead frame, an LED chip mounted on the lead frame, and a hexahedral molding part that embeds the lead frame and the LED chip.

[0015] The above surface light source device may further include a lens portion formed on the light-emitting surface of the transparent resin layer.

[0016] The above lens unit may include a dispersion lens formed on top of the LED light source. In this case, the dispersion lens may have a bat-wing shape with a concave central portion in a convex hemispherical shape.

[0017] The above lens part may be a micro optic lens in which a concave lens is formed with a concave portion formed inside the transparent resin layer or a convex lens in which a convex portion is formed in the transparent resin layer.

[0018] The above micro optic lens can be formed on the entire light-emitting surface of the transparent resin layer.

[0019] The above micro-optic lens may have different arrangements of micro-optic lenses in the first region, which is the upper region of the LED light source, and in the second region, which is the region excluding the first region. In this case, the micro-optic lens arrangement in the first region may be formed to have a wider interval than the micro-optic lens arrangement in the second region.

[0020] The above surface light source device may further include a light-shielding portion formed in an upper area of ​​the LED light source and printed on the upper surface of the transparent resin layer on which the micro-optic lens is formed.

[0021] The above-mentioned light-shielding portion may include a light-shielding pad covering the upper portion of the LED light source, and a light-shielding pattern formed on the outside of the light-shielding pad so as to be spaced apart from the light-shielding pad and formed so that the light leakage ratio increases as the distance from the light source increases.

[0022] The above-mentioned shading pad and shading pattern may have a transmittance of 5 to 30% for transmitting light emitted from the LED light source.

[0023] The above transparent resin layer can form a space around the LED light source.

[0024] The separation space formed in the above transparent resin layer can be formed in a cylindrical shape with a constant distance from the center of the LED light source to the wall surface.

[0025] The separation space formed in the above transparent resin layer can be formed in a polygonal column shape with a constant distance from the center of the LED light source to the center of each wall surface.

[0026]

[0027] According to one embodiment of the present invention, a surface light source device including a plurality of LED light sources that emit light to the upper and side surfaces and a transparent resin layer can be obtained to improve the luminance distribution of a light-emitting surface when using an LED light source that is a point light source.

[0028]

[0029] Figure 1 is a configuration diagram of a surface light source device according to one embodiment of the present invention.

[0030] Figure 2 is a configuration diagram of an LED light source used in a surface light source device according to one embodiment of the present invention.

[0031] Figure 3 is a configuration diagram of a surface light source device according to another embodiment of the present invention.

[0032] Fig. 4 is a configuration diagram of a surface light source device according to another embodiment of the present invention.

[0033] Fig. 5 is a configuration diagram of a surface light source device according to another embodiment of the present invention.

[0034] Fig. 6 is a configuration diagram of a surface light source device according to another embodiment of the present invention.

[0035] Fig. 7 is a configuration diagram of a surface light source device according to another embodiment of the present invention.

[0036] Fig. 8 is a configuration diagram of a surface light source device according to another embodiment of the present invention.

[0037] Fig. 9 is a drawing for explaining the effect of a surface light source device according to another embodiment of the present invention.

[0038] Fig. 10 is an example in which a cylindrical space is formed in a transparent resin layer.

[0039] Figure 11 is an example in which a square column-shaped space is formed in a transparent resin layer.

[0040] Figure 12 is an example in which a pentagonal column-shaped space is formed in a transparent resin layer.

[0041] Figure 13 is an example in which a hexagonal column-shaped space is formed in a transparent resin layer.

[0042]

[0043] One embodiment of the present invention can provide a surface light source device including a PCB substrate having circuit wiring formed therein, a plurality of LED light sources mounted on the PCB substrate and emitting light to the upper surface and side surfaces, and a transparent resin layer embedding the plurality of LED light sources and guiding light output from the LED light sources to output light to one surface.

[0044]

[0045] Hereinafter, the present invention will be described in detail with reference to the attached drawings.

[0046]

[0047] Figure 1 is a configuration diagram of a surface light source device according to one embodiment of the present invention.

[0048] Referring to FIG. 1, a surface light source device (100) according to the present embodiment may include a PCB substrate (110), an LED light source (120), and a transparent resin layer (130).

[0049] A PCB substrate (110) is a substrate that can form wiring lines inside a plurality of layers of the substrate and mount electronic components on the surface. In the present embodiment, the PCB substrate (110) may have wiring lines formed inside a substrate body in which a plurality of layers are laminated, and a portion of the wiring lines may be formed to be exposed on the upper portion of the substrate so as to enable contact with components to be mounted, such as LEDs. A PSR layer may be formed on the surface of the PCB substrate body. The PSR (Photo Imageable Solder Resist) layer may be formed to protect the circuit by coating an invariable compound ink that is durable under a chemical environment and at the same time prevent the occurrence of a solder gap phenomenon between circuits during the soldering process.

[0050] The LED light source (120) may be mounted on the PCB substrate (110). The LED light source may be a light source that uses an LED, which is a semiconductor that converts electrical energy into light energy. In the present embodiment, a plurality of LED light sources may be mounted on the PCB substrate. In the surface light source device according to the present embodiment, the LED light source (120) may be mounted in a direct form. The surface light source device according to the present embodiment may be applied to automobile taillights or DRLs. Therefore, unlike a flat surface light source applied to a BLU of an electronic product, LEDs may be mounted in the middle of the surface light source to form a unique light-emitting form of the surface light source. In the present embodiment, the LED light source (120) may be an LED light source that emits light to the top and sides. Conventional LED light sources often use an LED package that mounts a lead frame and an LED chip inside a housing, forms a molding that covers the LED chip inside the housing, and emits light to the side or top. The LED light source used in the surface light source device according to the present embodiment can form an LED package with a light-transmitting molding part without using an opaque housing.

[0051] An example of an LED light source used in the present embodiment is illustrated in FIG. 2. Referring to FIG. 2, an LED light source (220) used in the present embodiment may include a lead frame (221), an LED chip (222) mounted on the lead frame, and a molding part (223) in which the lead frame and the LED chip are embedded. A portion of the lead frame embedded in the molding part (223) may extend outside the molding part to provide an electrical connection to the LED chip. The molding part (223) may be formed of a light-transmitting material. The molding part may include a phosphor that converts light emitted from the LED chip into a different color. In the present embodiment, the molding part may be formed to have a hexahedral shape. When the molding part is formed in a hexahedral shape, light may be emitted from the upper surface and side surfaces of the molding part, except for the lower surface in which the lead frame on which the LED chip is mounted is arranged. In the present embodiment, the LED light source may apply a white resist to the upper surface of the hexahedral molding portion. By applying the white resist, the brightness of light emitted from the upper surface of the hexahedral molding portion can be reduced and the brightness of light emitted from the side surface of the hexahedral molding portion can be increased.

[0052] The transparent resin layer (130) is disposed on the PCB substrate (110) and can guide the light output from the LED light source (120) to output the light to one side. The transparent resin layer (130) can include a transparent resin such as PC, PMMA, PVC, or silicone. In the present embodiment, the transparent resin layer (130) can be formed by an insert injection process. In addition, the transparent resin layer (130) can be manufactured separately by an injection process and then mounted on the PCB substrate (110) to cover the LED light source (120). In the present embodiment, the transparent resin layer (130) can be formed to embed the LED light source (120). At this time, the embedding can be performed so that there is no space between the LED light source (120) and the transparent resin layer (130). In addition, the LED light source (120) and the transparent resin layer (130) may be embedded so as to have a predetermined gap between them. In this case, by forming a gap between the LED light source (120) and the transparent resin layer (130), the light emitted from the LED light source (120) is refracted during the process of entering the transparent resin layer (130), thereby further increasing the dispersion of the light. In addition, the gap between the LED light source (120) and the transparent resin layer (130) may be filled with a material different from the transparent resin layer (130).

[0053] The surface light source device (100) according to the present embodiment may further include a diffusion powder (140) in the transparent resin layer (130) to output light input from the LED light source (120) to one surface of the transparent resin layer (130). The diffusion powder may be selected from known diffusion powders such as TiO2 and SiO2.

[0054]

[0055] The surface light source device (100) according to the present embodiment may further include a lens unit on the light-emitting surface of the transparent resin layer (130). In the present embodiment, the lens unit may include a dispersion lens (150) formed in an upper region of the LED light source (120) to disperse light output from the upper portion of the light source laterally. Here, the upper region of the LED light source (120) does not only mean the directly upper portion where the LED light source is placed, but may also be placed in the upper region of the LED light source (120) but may be placed outside the directly upper region of the LED light source (120) depending on the size or shape of the dispersion lens. For example, when viewed from above, the dispersion lens (150) may be formed in a shape that covers the LED light source (120). In the present embodiment, the dispersion lens (150) may be formed in a bat-wing shape with a concave center portion in a convex hemispherical shape. By arranging a batwing-shaped dispersion lens (150) in the upper region of the LED light source (120) as in the present embodiment, the light output from the LED light source in an upward direction can be dispersed laterally, thereby improving the light emission uniformity of the surface light source device according to the present embodiment. The dispersion lens (150) may be formed of the same material as the transparent resin layer (130). In addition, the dispersion lens (150) and the transparent resin layer (130) may be integrally formed by an injection molding process. The dispersion lens (150) may also be formed of a different material from the transparent resin layer (130). In this case, the dispersion lens (150) may be adhered to the transparent resin layer (130) through a separate process.

[0056]

[0057] Figure 3 is a configuration diagram of a surface light source device according to another embodiment of the present invention.

[0058] Referring to FIG. 3, a surface light source device (300) according to the present embodiment may include a PCB substrate (310), an LED light source (320), a transparent resin layer (330), and a dispersion lens (350).

[0059] A PCB substrate (310) is a substrate that can form wiring lines inside a plurality of layers of the substrate and mount electronic components on the surface. In the present embodiment, the PCB substrate (310) may have wiring lines formed inside a substrate body in which a plurality of layers are laminated, and a portion of the wiring lines may be formed to be exposed on the upper portion of the substrate so as to enable contact with components to be mounted, such as LEDs. A PSR layer may be formed on the surface of the PCB substrate body. The PSR (Photo Imageable Solder Resist) layer may be formed to protect the circuit by coating an invariable compound ink that is durable under a chemical environment and at the same time prevent the occurrence of a solder gap phenomenon between circuits during the soldering process.

[0060] The LED light source (320) may be mounted on the PCB substrate (310). The LED light source may be a light source that uses an LED, which is a semiconductor that converts electrical energy into light energy. In the present embodiment, a plurality of LED light sources may be mounted on the PCB substrate. In the surface light source device according to the present embodiment, the LED light source (320) may be mounted in a direct form. The surface light source device according to the present embodiment may be applied to automobile taillights or DRLs. Therefore, unlike a flat surface light source applied to a BLU of an electronic product, LEDs may be mounted in the middle of the surface light source to form a unique light-emitting form of the surface light source. In the present embodiment, the LED light source (320) may be an LED light source that emits light to the top and sides. Conventional LED light sources often use an LED package that mounts a lead frame and an LED chip inside a housing, forms a molding that covers the LED chip inside the housing, and emits light to the side or top. The LED light source used in the surface light source device according to the present embodiment can form an LED package with a light-transmitting molding part without using an opaque housing. The LED light source (320) used in the present embodiment can include a lead frame, an LED chip mounted on the lead frame, and a molding part embedding the lead frame and the LED chip. A portion of the lead frame embedded in the molding part can extend outside the molding part to provide an electrical connection to the LED chip. The molding part can be formed of a light-transmitting material. The molding part can include a phosphor that converts light emitted from the LED chip into a different color. In the present embodiment, the molding part can be formed to have a hexahedral shape. When the hexahedral molding part is formed, light can be emitted from the upper surface and side surfaces of the molding part except for the lower surface in which the lead frame on which the LED chip is mounted is arranged. In the present embodiment, the LED light source can apply a white resist to the upper surface of the hexahedral molding part.By applying the above white resist, the brightness of light emitted from the upper surface of the hexahedral molding part can be reduced and the brightness of light emitted from the side surface of the hexahedral molding part can be increased.

[0061] The transparent resin layer (330) is disposed on the PCB substrate (310) and can guide the light output from the LED light source (320) to output the light to one side. The transparent resin layer (330) can include a transparent resin such as PC, PMMA, PVC, or silicone. In the present embodiment, the transparent resin layer (330) can be formed by an insert injection process. In addition, the transparent resin layer (330) can be manufactured separately by an injection process and then mounted on the PCB substrate (310) to cover the LED light source (320). In the present embodiment, the transparent resin layer (330) can be formed to embed the LED light source (320). At this time, the embedding can be performed so that there is no space between the LED light source (320) and the transparent resin layer (330). In addition, the LED light source (320) and the transparent resin layer (330) may be embedded so as to have a predetermined gap between them. In this case, by forming a gap between the LED light source (320) and the transparent resin layer (330), the light emitted from the LED light source (320) is refracted during the process of entering the transparent resin layer (330), thereby further increasing the dispersion of the light. In addition, the gap between the LED light source (320) and the transparent resin layer (330) may be filled with a material different from the transparent resin layer (330).

[0062] The surface light source device (300) according to the present embodiment may further include a diffusion powder (not shown) in the transparent resin layer (330) to output light input from the LED light source (320) to one side of the transparent resin layer (330). The diffusion powder may be selected from known diffusion powders such as TiO2 and SiO2.

[0063] The dispersion lens (350) is formed in the upper region of the LED light source (320) and can disperse the light output from the upper region of the light source laterally. Here, the upper region of the LED light source (320) does not only mean the directly upper region where the LED light source is placed, but may be placed in the upper region of the LED light source (320) but may be placed outside the directly upper region of the LED light source (320) depending on the size or shape of the dispersion lens. For example, the dispersion lens (350) may be formed in a shape that covers the LED light source (320) when viewed from above. In the present embodiment, the dispersion lens (350) may be formed in a bat-wing shape with a concave center in a convex hemispherical shape. By arranging the bat-wing-shaped dispersion lens (350) in the upper region of the LED light source (320) as in the present embodiment, the light output from the LED light source upward can be dispersed laterally, thereby improving the light emission uniformity of the surface light source device according to the present embodiment. The above dispersion lens (350) may be formed of the same material as the transparent resin layer (330). In addition, the dispersion lens (350) and the transparent resin layer (330) may be formed integrally through an injection molding process. The dispersion lens (350) may also be formed of a different material from the transparent resin layer (330). In this case, the dispersion lens (350) may be adhered to the transparent resin layer (330) through a separate process.

[0064] The surface light source device (300) according to the present embodiment may further include a micro-optic lens (not shown) on the light-emitting surface of the transparent resin layer (330). In the present embodiment, the micro-optic lens may be formed in an area on the upper surface of the transparent resin layer (330) where the dispersion lens (350) is not formed. The micro-optic lens may be formed integrally with the transparent resin layer (330). The micro-optic lens may be a concave lens formed concavely in the transparent resin layer (330) or a convex lens formed convexly in the transparent resin layer. Alternatively, the micro-optic lens may be a mixed form of a concave lens and a convex lens. In the surface light source device according to the present embodiment, light passing through the transparent resin layer (330) may be reflected by total reflection within the transparent resin layer, and then may be emitted to the outside when the total reflection is broken at the light-emitting surface of the transparent resin layer. In this embodiment, by forming a micro-optic lens on the light-emitting surface of the transparent resin layer, it is possible to improve the light that is totally reflected within the transparent resin layer from being emitted to the outside.

[0065]

[0066] Figure 4 is a configuration diagram of a surface light source device according to another embodiment of the present invention.

[0067] Referring to FIG. 4, a surface light source device (400) according to the present embodiment may include a PCB substrate (410), an LED light source (420), a transparent resin layer (430), and a micro optic lens (460).

[0068] A PCB substrate (410) is a substrate that can form wiring lines inside a plurality of layers of the substrate and mount electronic components on the surface. In the present embodiment, the PCB substrate (410) may have wiring lines formed inside a substrate body in which a plurality of layers are laminated, and a portion of the wiring lines may be formed to be exposed on the upper portion of the substrate so as to enable contact with components to be mounted, such as LEDs. A PSR layer may be formed on the surface of the PCB substrate body. The PSR (Photo Imageable Solder Resist) layer may be formed to protect the circuit by coating an invariable compound ink that is durable under a chemical environment and at the same time prevent the occurrence of a solder gap phenomenon between circuits during the soldering process.

[0069] An LED light source (420) may be mounted on the PCB substrate (410). The LED light source may be a light source that uses an LED, which is a semiconductor that converts electrical energy into light energy. In the present embodiment, a plurality of LED light sources may be mounted on the PCB substrate. In the surface light source device according to the present embodiment, the LED light source (420) may be mounted in a direct shape. The surface light source device according to the present embodiment may be applied to automobile taillights or DRLs. Therefore, unlike a flat surface light source applied to a BLU of an electronic product, LEDs may be mounted in the middle of the surface light source to form a unique light-emitting form of the surface light source.

[0070] In the present embodiment, the LED light source (420) may be an LED light source that emits light to the top and sides. Conventional LED light sources often use LED packages that mount a lead frame and an LED chip inside a housing, form a molding that covers the LED chip inside the housing, and emit light to the sides or top. The LED light source used in the surface light source device according to the present embodiment can form an LED package with a light-transmitting molding part without using an opaque housing. In the present embodiment, the LED light source may include a lead frame, an LED chip mounted on the lead frame, and a molding part that embeds the lead frame and the LED chip. A portion of the lead frame embedded in the molding part may extend outside the molding part to provide an electrical connection to the LED chip. The molding part may be formed of a light-transmitting material. The molding part may include a phosphor that converts light emitted from the LED chip into a different color. In the present embodiment, the molding part may be formed to have a hexahedral shape. When forming a hexahedral molding part, light can be emitted from the upper surface and side surfaces of the molding part except for the lower surface in which the lead frame on which the LED chip is mounted is arranged. In the present embodiment, the LED light source can apply a white resist to the upper surface of the hexahedral molding part. By applying the white resist, the brightness of the light emitted from the upper surface of the hexahedral molding part can be reduced and the brightness of the light emitted from the side surfaces of the hexahedral molding part can be increased.

[0071] The transparent resin layer (430) is disposed on the PCB substrate (410) and can guide the light output from the LED light source (420) to output the light to one side. The transparent resin layer (430) can include a transparent resin such as PC, PMMA, PVC, or silicone. In the present embodiment, the transparent resin layer (430) can be formed by an insert injection process. In addition, the transparent resin layer (430) can be manufactured separately by an injection process and then mounted on the PCB substrate (410) to cover the LED light source (420). In the present embodiment, the transparent resin layer (430) can be formed to embed the LED light source (320). At this time, the embedding can be performed so that there is no space between the LED light source (420) and the transparent resin layer (430). In addition, the LED light source (420) and the transparent resin layer (430) may be embedded so as to have a predetermined gap between them. In this case, by forming a gap between the LED light source (420) and the transparent resin layer (430), the light emitted from the LED light source (420) is refracted during the process of entering the transparent resin layer (430), thereby further increasing the dispersion of the light. In addition, the gap between the LED light source (420) and the transparent resin layer (430) may be filled with a material different from the transparent resin layer (430).

[0072] The micro-optic lens (460) may be formed on the light-emitting surface of the transparent resin layer (430). In the present embodiment, the micro-optic lens (460) may be formed as a part of the transparent resin layer (430). The micro-optic lens (440) may be a concave lens formed concavely in the transparent resin layer or a convex lens formed convexly in the transparent resin layer. Alternatively, the micro-optic lens may be a mixed form of a concave lens and a convex lens. In the present embodiment, light passing through the transparent resin layer (430) may be reflected by total reflection within the transparent resin layer and then broken at the light-emitting surface of the transparent resin layer to be emitted to the outside. In the present embodiment, by forming the micro-optic lens on the light-emitting surface of the transparent resin layer, light that is totally reflected within the transparent resin layer may be emitted to the outside. In the present embodiment, the micro-optic lens (460) may be formed only in a portion of the light-emitting surface of the transparent resin layer (430). The micro-optic lens may also be formed on the entire light-emitting surface of the transparent resin layer. When the micro-optic lens is formed only in a portion of the light-emitting surface of the transparent resin layer, a separate dispersion lens may be formed in the upper region of the LED light source on the upper surface of the transparent resin layer. The dispersion lens may be formed in a batwing shape, and by forming the dispersion lens in the upper region of the LED light source, the light emitted upward from the LED light source is dispersed laterally, thereby improving the light uniformity of the surface light source device according to the present embodiment.

[0073] The surface light source device (400) according to the present embodiment may further include a diffusion powder (440) in the transparent resin layer (430) to output light input from the LED light source (420) to one side of the transparent resin layer (430). The diffusion powder may be selected from known diffusion powders such as TiO2 and SiO2.

[0074]

[0075] Figure 5 is a configuration diagram of a surface light source device according to another embodiment of the present invention.

[0076] FIG. 5 is a drawing of the upper surface of a surface light source device (500) according to the present embodiment. The surface light source device (500) according to the present embodiment may include a PCB substrate (not shown), an LED light source (520) mounted on the PCB substrate, a transparent resin layer (530) covering the LED light source, and micro-optic lenses (560) formed on the upper surface of the transparent resin layer. In the present embodiment, the micro-optic lenses (560) may be formed to have the same intervals over the entire upper surface of the transparent resin layer (530). In the transparent resin layer in the upper region of the LED light source, the incident angle of light incident from the LED light source to the upper surface of the transparent resin layer is large, so that total reflection hardly occurs and the light can be emitted directly to the outside of the transparent resin layer. In contrast, since the light from the light source reaches the upper surface of the transparent resin layer between the LED light sources at an angle, as the incident angle of the light to the upper surface of the transparent resin layer decreases, the light may not be emitted to the outside of the transparent resin layer due to total reflection. In the surface light source device according to the present embodiment, by forming a micro-optic lens (560) on the upper surface of the transparent resin layer, light can be reduced from being reflected back into the transparent resin layer due to total reflection and emitted outside the transparent resin layer. By doing so, the luminance of the upper surface area of ​​the transparent resin layer between the LED light sources can be increased. As a result, the luminance of the entire surface light source device can be made uniform.

[0077]

[0078] Figure 6 is a configuration diagram of a surface light source device according to another embodiment of the present invention.

[0079] Fig. 6 is a drawing of the upper surface of a surface light source device (600) according to the present embodiment. The surface light source device (600) according to the present embodiment may include a PCB substrate (not shown), an LED light source (620) mounted on the PCB substrate, a transparent resin layer (630) covering the LED light source, and a micro-optic lens (660) formed on the upper surface of the transparent resin layer.

[0080] In the present embodiment, the arrangement of the micro-optic lenses may be different by dividing the first region, which is the upper region of the LED light source (620), and the second region, which is another region excluding the first region. In the present embodiment, the arrangement of the micro-optic lenses (661) in the first region may be formed to have a wider interval than the arrangement of the micro-optic lenses (662) in the second region.

[0081] In the transparent resin layer in the upper region of the LED light source, the light incident from the LED light source to the upper surface of the transparent resin layer has a large incident angle, so that total reflection hardly occurs and the light can be emitted directly to the outside of the transparent resin layer. In contrast, since the light from the light source reaches the upper surface of the transparent resin layer between the LED light sources at an angle, as the incident angle of the light to the upper surface of the transparent resin layer decreases, the light may not be emitted to the outside of the transparent resin layer due to total reflection. In the surface light source device according to the present embodiment, a micro-optic lens (660) is formed on the upper surface of the transparent resin layer, and in the region between the LED light sources, where total reflection occurs where the light incident from the light source is reflected back into the transparent resin layer, the gap between the micro-optic lenses can be made closer to reduce total reflection. By doing so, the luminance of the region of the upper surface of the transparent resin layer between the LED light sources can be increased. As a result, the luminance of the entire surface light source can be made uniform.

[0082]

[0083] Fig. 7 is a configuration diagram of a surface light source device according to another embodiment of the present invention.

[0084] Referring to FIG. 7, a surface light source device (700) according to the present embodiment may include a PCB substrate (710), an LED light source (720), a transparent resin layer (730), a micro optic lens (760), and a light shielding portion (770).

[0085] A PCB substrate (710) is a substrate that can form wiring lines inside a plurality of layers of the substrate and mount electronic components on the surface. In the present embodiment, the PCB substrate (710) may have wiring lines formed inside a substrate body in which a plurality of layers are laminated, and a portion of the wiring lines may be formed to be exposed on the upper portion of the substrate so as to enable contact with components to be mounted, such as LEDs. A PSR layer may be formed on the surface of the PCB substrate body. The PSR (Photo Imageable Solder Resist) layer may be formed to protect the circuit by coating an invariable compound ink that is durable under a chemical environment and at the same time prevent the occurrence of a solder gap phenomenon between circuits during the soldering process.

[0086] An LED light source (720) may be mounted on the PCB substrate (710). The LED light source may be a light source that uses an LED, which is a semiconductor that converts electrical energy into light energy. In the present embodiment, a plurality of LED light sources may be mounted on the PCB substrate. In the surface light source device according to the present embodiment, the LED light source (720) may be mounted in a direct shape. The surface light source device according to the present embodiment may be applied to automobile taillights or DRLs. Therefore, unlike a flat surface light source applied to a BLU of an electronic product, LEDs may be mounted in the middle of the surface light source, and a unique light-emitting form of the surface light source may be formed through these.

[0087] In the present embodiment, the LED light source (720) may be an LED light source that emits light to the top and sides. Conventional LED light sources often use LED packages that mount a lead frame and an LED chip inside a housing, form a molding that covers the LED chip inside the housing, and emit light to the sides or top. The LED light source used in the surface light source device according to the present embodiment can form an LED package with a light-transmitting molding part without using an opaque housing. In the present embodiment, the LED light source may include a lead frame, an LED chip mounted on the lead frame, and a molding part that embeds the lead frame and the LED chip. A portion of the lead frame embedded in the molding part may extend outside the molding part to provide an electrical connection to the LED chip. The molding part may be formed of a light-transmitting material. The molding part may include a phosphor that converts light emitted from the LED chip into a different color. In the present embodiment, the molding part may be formed to have a hexahedral shape. When forming a hexahedral molding part, light can be emitted from the upper surface and side surfaces of the molding part except for the lower surface in which the lead frame on which the LED chip is mounted is arranged. In the present embodiment, the LED light source can apply a white resist to the upper surface of the hexahedral molding part. By applying the white resist, the brightness of the light emitted from the upper surface of the hexahedral molding part can be reduced and the brightness of the light emitted from the side surfaces of the hexahedral molding part can be increased.

[0088] A transparent resin layer (730) is disposed on the PCB substrate (710) and can guide light output from the LED light source (720) to output light to one side. The transparent resin layer (730) can include a transparent resin such as PC, PMMA, PVC, or silicone. In the present embodiment, the transparent resin layer (730) can be formed by an insert injection process. In addition, the transparent resin layer (730) can be manufactured separately by an injection process and then mounted on the PCB substrate (710) to cover the LED light source (720). In the present embodiment, the transparent resin layer (730) can be formed to embed the LED light source (720). At this time, the embedding can be performed so that there is no space between the LED light source (720) and the transparent resin layer (730). In addition, the LED light source (720) and the transparent resin layer (730) may be embedded so as to have a predetermined gap between them. In this case, by forming a gap between the LED light source (720) and the transparent resin layer (730), the light emitted from the LED light source (720) is refracted during the process of entering the transparent resin layer (730), thereby further increasing the dispersion of the light. In addition, the gap between the LED light source (720) and the transparent resin layer (730) may be filled with a material different from the transparent resin layer (730).

[0089] A micro-optic lens (760) may be formed on the light-emitting surface of the transparent resin layer (730). In the present embodiment, the micro-optic lens (760) may be formed as a part of the transparent resin layer (730). The micro-optic lens (740) may be a concave lens formed concavely in the transparent resin layer or a convex lens formed convexly in the transparent resin layer. Alternatively, the micro-optic lens may be a mixed form of a concave lens and a convex lens. In the present embodiment, light passing through the transparent resin layer (730) may be reflected by total reflection within the transparent resin layer and then broken at the light-emitting surface of the transparent resin layer to be emitted to the outside. In the present embodiment, by forming a micro-optic lens on the light-emitting surface of the transparent resin layer, light that is totally reflected within the transparent resin layer may be emitted to the outside. In the present embodiment, the micro-optic lens (760) may be formed only in a portion of the light-emitting surface of the transparent resin layer (730). The micro-optic lens may also be formed on the entire light-emitting surface of the transparent resin layer. When the micro-optic lens is formed only in a portion of the light-emitting surface of the transparent resin layer, a separate dispersion lens may be formed in the upper region of the LED light source on the upper surface of the transparent resin layer. The dispersion lens may be formed in a batwing shape, and by forming the dispersion lens in the upper region of the LED light source, the light emitted upward from the LED light source is dispersed laterally, thereby improving the light uniformity of the surface light source device according to the present embodiment.

[0090] The surface light source device (700) according to the present embodiment may further include a diffusion powder (740) in the transparent resin layer (730) to output light input from the LED light source (720) to one side of the transparent resin layer (730). The diffusion powder may be selected from known diffusion powders such as TiO2 and SiO2.

[0091] The surface light source device (700) according to the present embodiment may further include a light-shielding portion (770). The light-shielding portion (770) is printed on the upper surface of the transparent resin layer on which the micro-optic lens is formed, and may be formed in the upper region of the LED light source. The light-shielding portion (770) may reflect light emitted from the LED light source (720) to the upper region of the LED light source back into the transparent resin layer (730). The light thus reflected may move inside the transparent resin layer (730) and be emitted into an area where the light-shielding portion is not formed. Consequently, when the light-shielding portion (770) is formed, the light intensity emitted from an area of ​​the transparent resin layer (770) where the light-shielding portion is not formed may be increased compared to a case where the light-shielding portion is not formed, thereby improving the overall light uniformity of the surface light source. The light-shielding portion (770) may use white ink containing SiO2 or TiO2. The above-mentioned light-shielding portion may be formed to have a transmittance of 1 to 99%, preferably 5 to 30%. By doing so, dark areas can be prevented from occurring in the area where the light-shielding portion (770) is formed, thereby improving light uniformity across the entire surface light source.

[0092] In the present embodiment, the light-shielding portion (770) may include a light-shielding pad (771) covering the upper portion of the LED light source, and a light-shielding pattern (772) formed on the outside of the light-shielding pad so as to be spaced apart from the light-shielding pad and formed so that the light leakage ratio increases as it gets farther from the light source. In the present embodiment, the light-shielding pad and the light-shielding pattern may have a transmittance of 5 to 30% for transmitting light emitted from the LED light source. The light-shielding pattern (772) is formed in an outer region of the light-shielding pad (771), and may be formed in the form of a plurality of patterns whose sizes gradually decrease so that the light leakage ratio increases as it gets farther from the light source. In the present embodiment, the light-shielding pattern (462) is formed in a dot shape, but the shape of the light-shielding pattern may be implemented in various ways. In addition, in the present embodiment, a shading pattern (772) may be formed on the light-emitting surface of the transparent resin layer (730), and a shading pattern in a positive shape may be formed so that light is emitted to an area where the shading pattern is not formed. Conversely, a shading pad may be formed on the entire light-emitting surface of the transparent resin layer (730), and a shading pattern may be formed in an engraved shape in which a part of the shading pad is removed so that the light leakage rate increases as it gets farther away from the light source. If the shading pattern is formed in an engraved shape, the shading pattern may be formed so that the area removed from the shading pad becomes larger as it gets farther away from the light source.

[0093]

[0094] Figure 8 is a configuration diagram of a surface light source device according to another embodiment of the present invention.

[0095] Referring to FIG. 8, a surface light source device (800) according to the present embodiment may include a PCB substrate (810), an LED light source (820), and a transparent resin layer (830).

[0096] A PCB substrate (810) is a substrate that can form wiring lines inside a plurality of layers of the substrate and mount electronic components on the surface. In the present embodiment, the PCB substrate (810) can have wiring lines formed inside a substrate body in which a plurality of layers are laminated, and a portion of the wiring lines can be formed to be exposed on the upper portion of the substrate so as to enable contact with components to be mounted, such as an LED light source. A PSR (Photo Imageable Solder Resist) layer can be formed on the surface of the PCB substrate body. The PSR (Photo Imageable Solder Resist) layer can be formed to protect the circuit by coating an invariable compound ink that is durable under a chemical environment and at the same time prevent the occurrence of a solder gap phenomenon between circuits during the soldering process.

[0097] The LED light source (820) may be mounted on the PCB substrate (810). The LED light source may be a light source that uses an LED, which is a semiconductor that converts electrical energy into light energy. In the present embodiment, a plurality of LED light sources may be mounted on the PCB substrate. In the surface light source device according to the present embodiment, the LED light source (820) may be mounted in a direct shape. The surface light source device according to the present embodiment may be applied to automobile taillights or DRLs. Therefore, unlike the flat surface light source applied to the BLU of electronic products, LEDs may be mounted in the middle of the surface light source to form a unique light-emitting form of the surface light source. In the present embodiment, the LED light source (820) may be an LED light source that emits light to the top and sides. Conventional LED light sources often use an LED package that mounts a lead frame and an LED chip inside a housing, forms a molding that covers the LED chip inside the housing, and emits light to the side or top. The LED light source used in the surface light source device according to the present embodiment can form an LED package with a light-transmitting molding part without using an opaque housing. In the present embodiment, the LED light source can include a lead frame, an LED chip mounted on the lead frame, and a molding part embedding the lead frame and the LED chip. A portion of the lead frame embedded in the molding part can extend outside the molding part to provide an electrical connection to the LED chip. The molding part can be formed of a light-transmitting material. The molding part can include a phosphor that converts light emitted from the LED chip into a different color. In the present embodiment, the molding part can be formed to have a hexahedral shape. When the molding part is formed in a hexahedral shape, light can be emitted from the upper surface and side surfaces of the molding part except for the lower surface in which the lead frame on which the LED chip is mounted is arranged.

[0098] The transparent resin layer (830) is disposed on the PCB substrate (810) and can guide the light output from the LED light source (820) to output the light to one side. In the present embodiment, the transparent resin layer (830) can form a space around the LED light source (820). The transparent resin layer (830) can include a transparent resin such as PC, PMMA, PVC, or silicone. In the present embodiment, the transparent resin layer (830) can be formed by an insert injection process. In the surface light source device according to the present embodiment, in order to output the light input from the LED light source (820) to one side of the transparent resin layer (830), the transparent resin layer (830) can include a diffusion powder. The diffusion powder can be selected from known diffusion powders such as TiO2 and SiO2.

[0099] The separation space (831) formed in the transparent resin layer may be formed to have the same separation distance from the center of the LED light source. In the present embodiment, by forming a cylindrical separation space (831) around the LED light source (820), light emitted from the LED light source (820) in the upper and upper side directions can be directly emitted without being affected by the transparent resin layer (830). Light emitted from the LED light source (820) in the side direction is incident on the transparent resin layer (830) and can be emitted in the upper direction of the transparent resin layer (830) through scattering, total reflection, and reflection within the transparent resin layer. The separation space (831) formed in the transparent resin layer may be formed in various shapes, such as an elliptical columnar shape or a polygonal columnar shape.

[0100] In the present embodiment, the transparent resin layer (830) may be formed higher than the height of the LED light source (820). By forming the height of the transparent resin layer (830) higher than the height of the LED light source (820), only the light emitted in the upper and upper-side directions among the light emitted from the LED light source (820) that emits light to the upper surface and side surfaces can be directly emitted. The amount of light directly emitted from the LED light source (820) can be controlled depending on the height of the transparent resin layer (830).

[0101] In the present embodiment, a lens portion may be formed on the upper surface of the transparent resin layer (830). The lens portion may be a dispersion lens disposed in the upper region of the LED light source (820). In order for the dispersion lens to be disposed, the upper region of the separation space of the transparent resin layer (830) may be formed to be blocked with a transparent resin layer. The dispersion lens may be formed in a batwing shape with a concave center from a convex hemispherical shape. The dispersion lens may be formed in the upper region of the LED light source to disperse light output upward from the light source laterally. By disposing the batwing-shaped dispersion lens in the upper region of the LED light source as in the present embodiment, light output upward from the LED light source can be dispersed laterally, thereby improving the light emission uniformity of the surface light source device according to the present embodiment. The dispersion lens may be formed of the same material as the transparent resin layer. In addition, the dispersion lens and the transparent resin layer may be integrally formed by an injection process.

[0102] The surface light source device (800) according to the present embodiment may further include a micro-optic lens (not shown) on the light-emitting surface of the transparent resin layer (830). In the present embodiment, the micro-optic lens may be formed in an area on the upper surface of the transparent resin layer where a separation space (831) is not formed. The micro-optic lens may be formed integrally with the transparent resin layer. The micro-optic lens may be a concave lens formed concavely in the transparent resin layer or a convex lens formed convexly in the transparent resin layer. Alternatively, the micro-optic lens may be a mixed form of a concave lens and a convex lens. In the surface light source device according to the present embodiment, light passing through the transparent resin layer may be reflected by total reflection within the transparent resin layer and then broken at the light-emitting surface of the transparent resin layer to be emitted to the outside. In the present embodiment, by forming the micro-optic lens on the light-emitting surface of the transparent resin layer, light that is totally reflected within the transparent resin layer may be emitted to the outside.

[0103]

[0104] Fig. 9 is a drawing for explaining the effect of a surface light source device according to another embodiment of the present invention.

[0105] Fig. 9 (a) conceptually illustrates light emitted from a surface light source device in which a plurality of LED light sources (921, 922) are mounted on a PCB substrate to an external lens (990). Fig. 9 (b) conceptually illustrates light emitted from a surface light source device in which a plurality of LED light sources (921, 922) are mounted on a PCB substrate and a transparent resin layer (930) is formed between the LED light sources (921, 922) according to one embodiment of the present invention to an external lens (980).

[0106] In (a) of Fig. 9, the light emitted through the lens of the upper region of the first LED light source (921) may be combined with the light directly output to the upper portion of the first LED light source (921) and the light emitted in the upper side direction of the adjacent second LED light source (922). Here, among the entire portion of the lens (980), the upper regions of the first LED light source (921) and the second LED light source (922) may have increased luminance compared to other portions because the light output from the adjacent LED light sources overlaps. Therefore, the luminance uniformity of the entire surface of the lens (980) may be reduced.

[0107] In contrast, in Fig. 9 (b) showing a light source device according to one embodiment of the present invention, a portion of the light emitted in the upper side direction from the first LED light source and the second LED light source can be blocked by the transparent resin layer (930) disposed between the first LED light source (921) and the second LED light source (922). Accordingly, the overlapping of light in the lens (980) in the upper region of the first LED light source (921) and the second LED light source (922) can be reduced, so that the light uniformity over the entire lens surface can be improved.

[0108]

[0109] FIGS. 10 to 13 illustrate a lighting image and a brightness distribution graph of output light output from a surface light source device according to the shape of a separation space formed in a transparent resin layer in a surface light source device according to the present embodiment.

[0110] Fig. 10 is an example in which a cylindrical space is formed in a transparent resin layer. The cylindrical space formed in the transparent resin layer can be formed such that the cylindrical wall surface has a constant distance from the LED light source placed in the center. In the example of Fig. 10, a lighting image and a luminance distribution graph measured in the horizontal direction (A-A') and vertical direction (B-B') of the surface light source device are illustrated.

[0111] Fig. 11 illustrates an embodiment in which a square column-shaped space is formed in a transparent resin layer. The square column-shaped space formed in the transparent resin layer can be formed such that the central portion of each wall surface of the square column shape has a constant distance from the LED light source positioned in the center. In the embodiment of Fig. 11, it can be seen that the lighting image or luminance distribution graph appears similar to the embodiment of Fig. 10.

[0112] Fig. 12 illustrates an embodiment in which a pentagonal column-shaped space is formed in a transparent resin layer. The pentagonal column-shaped space formed in the transparent resin layer can be formed such that the central portion of each wall surface of the pentagonal column shape has a constant distance from the LED light source positioned in the center. In the embodiment of Fig. 12, it can be seen that the lighting image or luminance distribution graph appears similar to the embodiment of Fig. 10.

[0113] Fig. 13 illustrates an embodiment in which a hexagonal column-shaped space is formed in a transparent resin layer. The hexagonal column-shaped space formed in the transparent resin layer can be formed such that the central portion of each wall surface of the hexagonal column shape is at a constant distance from the LED light source positioned in the center. In the embodiment of Fig. 13, it can be seen that the lighting image or luminance distribution graph appears similar to the embodiment of Fig. 10.

[0114]

[0115] Although the present invention has been described above with reference to preferred embodiments and examples, it will be understood by those skilled in the art that various modifications and changes can be made to the present invention without departing from the spirit and scope of the present invention as set forth in the claims below.

Claims

1. PCB board with circuit wiring formed inside; A plurality of LED light sources mounted on the PCB substrate and emitting light to the upper and side surfaces; and A transparent resin layer that embeds the above plurality of LED light sources and guides the light output from the LED light sources to output light on one side. A surface light source device including:

2. In paragraph 1, Dispersant powder dispersed within the above transparent resin layer A surface light source device characterized by further including:

3. In paragraph 1, The above LED light source is, lead frame; An LED chip mounted on the lead frame; and A hexahedral molding part that embeds the above lead frame and LED chip A surface light source device characterized by including a .

4. In paragraph 1, A lens part formed on the light-emitting surface of the above transparent resin layer A surface light source device characterized by further including:

5. In paragraph 4, The above lens part, Dispersing lens formed on top of the LED light source A surface light source device characterized by including a .

6. In paragraph 5, The above dispersion lens is, A surface light source device characterized by a bat-wing shape with a concave central portion in a convex hemispherical shape.

7. In paragraph 4, The above lens part, A surface light source device characterized by being a micro optic lens formed with a concave lens having a concave portion formed inside the transparent resin layer or a convex lens having a convex portion formed in the transparent resin layer.

8. In paragraph 7, The above micro optic lens, A surface light source device characterized by being formed on the entire light-emitting surface of the above transparent resin layer.

9. In paragraph 7, The above micro optic lens, A surface light source device characterized in that the micro-optic lens arrangements of the first region, which is the upper region of the LED light source, and the second region, which is the region excluding the first region, are different.

10. In paragraph 9, A surface light source device characterized in that the micro-optic lens array of the first region is formed to have a wider gap than the micro-optic lens array of the second region.

11. In paragraph 7, A light-shielding portion formed on the upper area of the LED light source and printed on the upper surface of the transparent resin layer on which the above micro-optical lens is formed A surface light source device characterized by further including:

12. In paragraph 11, The above shading part is, A shading pad covering the upper portion of the LED light source; and A shading pattern formed on the outside of the shading pad so as to be spaced apart from the shading pad, and formed so that the light leakage rate increases as it gets farther from the light source. A surface light source device characterized by including:

13. In paragraph 12, A surface light source device characterized in that the above-mentioned shading pad and shading pattern have a transmittance of 5 to 30% for transmitting light emitted from the LED light source.

14. In paragraph 1, A surface light source device characterized in that the transparent resin layer forms a space around the LED light source.

15. In paragraph 14, The space formed in the above transparent resin layer is A surface light source device characterized in that the distance from the center of the LED light source to the wall surface is formed in a cylindrical shape.

16. In paragraph 14, The space formed in the above transparent resin layer is A surface light source device characterized in that it is formed in a polygonal prism shape with a constant distance from the center of the LED light source to the center of each wall surface.

Images