CN102610603A - light emitting device - Google Patents

Abstract

A light-emitting device comprises at least one substrate, a plurality of light-emitting units, at least one protrusion and a reflective material. The substrate has a substrate body and a patterned layer disposed on the substrate body. The light-emitting units are arranged on the substrate, each light-emitting unit is provided with at least one light-emitting diode core, and the light-emitting diode cores are arranged on the substrate and electrically connected with the substrate. The protrusion is correspondingly arranged around the at least one light-emitting unit, and the protrusion is substantially arranged on the patterning layer in an aligned mode. The reflective material is disposed on the protrusion. The light-emitting device of the invention can avoid the problem of light interference and can improve the utilization rate of light.

Description

light emitting device

technical field

The present invention relates to a light emitting device, in particular to a light emitting device with a light emitting diode tube core.

Background technique

A light-emitting diode is a light-emitting component made of semiconductor materials. The component has two electrode terminals. A voltage is applied between the terminals, and a very small voltage is passed through. Through the combination of electron holes, the remaining energy can be excited in the form of light. released.

Unlike ordinary incandescent bulbs, LEDs are cold-emitting, with low power consumption, long component life, no warm-up time, and fast response. In addition, it is small in size, resistant to vibration, suitable for mass production, and can be easily made into extremely small or array modules according to application requirements, so it can be widely used in indicators of lighting equipment, information, communication, and consumer electronics products And display devices, it has become one of the important components that are indispensable in daily life.

Please refer to FIG. 1 , a known light emitting device 1 composed of light emitting diodes includes a substrate 11 , at least one light emitting diode die 12 and an encapsulant 13 . FIG. 1 illustrates by taking four LED dies 12 disposed on a substrate 11 to form four light emitting units as an example.

Wherein, the light-emitting diode die 12 is arranged on the upper surface 111 of the substrate 11, and is electrically connected to the circuit layer (not shown) on the upper surface 111 of the substrate 11 by a bonding wire 121, and is electrically connected to an external circuit through the circuit layer, so as to The light emitting device 1 is driven. In addition, the encapsulants 13 respectively cover the LED dies 12 to protect the LED dies 12 from being polluted by dust, water vapor, or foreign objects, which may affect their light-emitting characteristics.

However, when the light-emitting device 1 is used as a display device, the lights of different light-emitting units will affect each other and cause cross talk. In addition, the light utilization efficiency of the light emitting unit is not high.

Therefore, how to provide a light-emitting device that can avoid the problem of light interference between light-emitting units and improve light utilization efficiency has become an important issue at present.

Contents of the invention

The purpose of the present invention is to provide a light emitting device which can avoid the problem of light interference between light emitting units and improve light utilization efficiency.

The present invention can be realized by adopting the following technical solutions.

A light emitting device according to the present invention includes at least one substrate, a plurality of light emitting units, at least one protrusion and a reflective material. The substrate has a substrate body and a patterned layer, and the patterned layer is arranged on the substrate body. The light-emitting units are arranged on the substrate, and each light-emitting unit has at least one light-emitting diode die, and the light-emitting diode die is arranged on the substrate and electrically connected with the substrate. The protrusions are correspondingly disposed around the at least one light-emitting unit, and the protrusions are substantially aligned on the patterned layer. A reflective material is disposed on the protrusion.

In an embodiment of the present invention, the LED die is disposed on the substrate by wire bonding or flip chip bonding.

In an embodiment of the present invention, the substrate body has an upper surface and a lower surface, the patterned layer is disposed on the upper surface of the substrate body, and the substrate has another patterned layer disposed on the lower surface of the substrate body.

In an embodiment of the present invention, the substrate body has at least one through hole disposed in alignment with the protrusion, and the through hole connects the patterned layer and another patterned layer.

In one embodiment of the invention, the protrusion is a conductor or an insulator.

In an embodiment of the present invention, when there are multiple protrusions, there is a gap or no gap between two adjacent protrusions.

In an embodiment of the present invention, the protrusions are arranged continuously or discontinuously around each light emitting unit.

In an embodiment of the invention, the height of the protrusion is greater than that of the light emitting unit.

In an embodiment of the invention, the height of the protrusions is between 50 microns and 800 microns.

In an embodiment of the present invention, the method for disposing the reflective material on the protrusion includes electroplating, or sticking, or spraying.

In an embodiment of the present invention, the material of the reflective material includes metal, or a mixture of epoxy resin or titanium dioxide and resin.

In one embodiment of the invention, the metal includes silver, or chromium, or nickel.

In an embodiment of the present invention, the light emitting device further includes an encapsulation material covering the LED die, and the encapsulation material is doped with phosphor.

In an embodiment of the present invention, the method for arranging protrusions corresponding to the surroundings of the light-emitting unit includes: disposing a spacer material on the patterned layer correspondingly and heating to form the protrusions.

In an embodiment of the present invention, the spacer material is disposed on the patterned layer by screen printing, or printing, or coating, or inkjet process, or directly placed.

In an embodiment of the invention, the material of the protrusion includes metal, metal oxide, resin or silica gel.

In an embodiment of the invention, the height of the protrusion is smaller than that of the encapsulation material.

In an embodiment of the invention, the height of the protrusion is less than or equal to the light emitting unit.

In an embodiment of the present invention, the protrusion forms an included angle with the substrate, and the included angle is greater than 60 degrees.

In an embodiment of the present invention, the light emitting device further includes a cover plate, which is disposed opposite to the substrate.

In an embodiment of the present invention, the cover plate is transparent and includes a fluorescent film or a fluorescent layer.

Based on the above, the light-emitting device according to the present invention is correspondingly arranged around the light-emitting unit through the protrusions, so that when the light-emitting device is used as a display device, the problem of interference caused by light rays from different light-emitting units can be avoided . In addition, the protrusion can also be used as a glue-retaining structure for disposing the packaging material on the LED tube core, so as to simplify the manufacturing process and reduce the manufacturing cost. Furthermore, the reflective material disposed on the protrusion can make the light emitted by the light-emitting diode tube core reflect by the reflective material to improve its light extraction efficiency, thereby improving the light utilization rate of the light emitting device.

In addition, the adhesion between the material of the protrusion and the patterned layer is greater than the adhesion between the material of the protrusion and the substrate body, so that the protrusion can be automatically aligned with the patterned layer (self-align), greatly improving the process efficiency and reduce costs.

Description of drawings

FIG. 1 is a schematic diagram of a known light emitting device;

Fig. 2A is a top view of the light emitting device according to the first embodiment of the present invention;

Fig. 2B is a cross-sectional view of line A-A in Fig. 2A;

Fig. 3 is a flow chart of the corresponding arrangement of protrusions around the light-emitting unit in the present invention;

4A to 4B are cross-sectional views of another aspect of the light emitting device of the present invention;

4C to 4G are top views of another aspect of the light emitting device of the present invention;

5 is a cross-sectional view of a light emitting device according to a second embodiment of the present invention;

6A is a top view of a light emitting device according to a third embodiment of the present invention; and

FIG. 6B is a partially enlarged schematic view of the connection portion of the substrate of the light emitting device according to the third embodiment of the present invention.

Description of main component symbols:

1, 2, 2a～2g, 3, 4: light emitting device

11, 21, 21b, 31, 41: substrate

111: upper surface

12, 221, 321: LED die

121: Wired

13: sealant

211, 311: substrate body

212, 212b, 213, 312: patterned layer

22, 22f, 22g, 32, 42: light emitting unit

23, 23a, 23c, 23d, 23e, 23f, 23g, 43: protrusions

24, 24c, 24d, 24e, 24f, 24g, 44: reflective material

25, 25a, 35, 45: Packaging material

36, 46: cover plate

37: link glue

A-A: Straight line

O: through hole

S01～S02: Steps

α: contact angle

θ: angle

Detailed ways

A light emitting device according to a preferred embodiment of the present invention will be described below with reference to related drawings, wherein the same elements will be described with the same reference numerals.

first embodiment

Please refer to FIG. 2A and FIG. 2B at the same time, wherein FIG. 2A is a top view of the light emitting device 2 according to the first embodiment of the present invention, and FIG. 2B is a cross-sectional view along the line A-A in FIG. 2A .

The light emitting device 2 includes at least one substrate 21 , a plurality of light emitting units 22 , at least one protrusion 23 and a reflective material 24 . The light-emitting device 2 of the present invention can be, for example, a display device, a traffic signal, a lighting device, an indicator device, an advertising billboard, a light bar (light bar) or a backlight module, and it is not limited here. its use.

The substrate 21 has a substrate body 211 and a patterned layer 212 , the substrate body 211 has an upper surface and a lower surface, and the patterned layer 212 is disposed on the upper surface of the substrate body 211 . Wherein, the substrate 21 can be partially transparent, completely transparent or opaque, and its material can include glass, or sapphire, or quartz, or ceramics, or glass fibers, or resinous materials, or metals, or polymer materials. . Here, the material of the substrate 21 is not limited, and a double-layer printed circuit board is taken as an example. In addition, the patterned layer 212 can be a thermally conductive metal material, such as copper, or silver, or gold. Here, copper is used as an example.

The light emitting unit 22 is disposed on the substrate 21 . Here, the light emitting units 22 are disposed on the upper surface of the substrate body 211 in a two-dimensional array as an example. Of course, the light emitting units 22 can also be arranged in other ways, such as one-dimensional arrangement, circular arrangement or irregular arrangement on the substrate 21 . Wherein, each light-emitting unit 22 has at least one light-emitting diode die 221, and the light-emitting diode die 221 is arranged on the upper surface of the substrate body 211 by wire bonding (wirebonding) or flip-chip bonding (flip chip), and is electrically connected to the substrate 21. sexual connection.

In this embodiment, each light-emitting unit 22 has a light-emitting diode die 221, and is bonded to the substrate 21 by wire bonding, and is electrically connected to the circuit layer (not shown in the figure), and is not electrically connected to the above-mentioned patterned layer 212. connect. The circuit layer is electrically connected to the driving circuit to drive the light emitting device 2 . The light-emitting unit 22 can be, for example, ultraviolet light, red light, or green light, or blue light, or blue-green light, or other light-emitting diode dies 221 that emit visible light or a combination thereof, so that the light emitted by the light-emitting unit 22 is monochromatic Light or mixed color light (for example, white light).

The protrusions 23 are correspondingly disposed around at least one light emitting unit 22 , here, each protrusion 23 is respectively disposed correspondingly around each light emitting unit 22 , and is arranged in a two-dimensional array. In addition, the protrusions 23 can be continuously or discontinuously disposed around each light emitting unit 22 , and the protrusions 23 are substantially aligned on the patterned layer 212 . That is to say, where the protrusions 23 are arranged, there is the patterned layer 212 arranged. Wherein, the continuous protrusions 23 can form a closed curve, and the shape of the closed curve can be substantially square, or rectangular, or circular, or triangular, or hexagonal, or polygonal. In this embodiment, a plurality of protrusions 23 are continuously and correspondingly disposed around each light emitting unit 22 , and the closed curve formed by the protrusions 23 is a circle as an example, but it is not limiting. In addition, the protrusion 23 can be a conductor or an insulator, and its material can include metal, metal oxide, resin or silicone, and the material of the metal can be tin or copper, for example.

Please refer to FIG. 3 , the method for arranging protrusions 23 correspondingly around the light-emitting unit 22 may include steps S01-S02, wherein step S01 is: a spacer material is correspondingly arranged on the patterned layer 212; and step S02 is : Heating is performed to form protrusions 23 . In step S01, the above-mentioned spacer material is correspondingly arranged on the patterned layer 212, and the way of setting can be, for example, by screen printing, or printing, or coating, or inkjet process, or directly placing the spacer material on the corresponding patterned layer 212. Layer 212, herein, is not limited. Wherein, the spacer material can be easily obtained material, such as washer, and its material can be tin or tin alloy, for example. Here, the material of the spacer is tin as an example. In addition, the shape of the spacer material can be square, circular or other shapes matching the patterned layer 212 , and its height (thickness) can be between 0.1-0.8 mm.

During the heating process (for example: reflow) in step S02, the spacer material will be partially or completely melted when heated to align with the patterned layer 212, and then form a solid protrusion 23 after cooling, and make the protrusion 23 substantially The upper alignment is disposed on the patterned layer 212 . It is worth mentioning that, before the reflow process, a layer of solder resist layer (solder resist layer) can be coated on the periphery of the patterned layer 212, such as the inner side and (or) outer side, so as to prevent the spacer material from overflowing when it is heated and melted. Patterned layer 212 . Wherein, the solder resist layer can be epoxy resin, commonly known as green paint.

Therefore, if the spacer material made of tin is disposed on the patterned layer 212 made of copper, when the spacer material is thermally melted, for example copper tin oxide (Cu3Sn) will be formed between the patterned layer 212 and the spacer material. Or the inter-metal compound (Inter-Metal Compound, IMC) of five tin six copper (Cu6Sn5). When the spacer material is thermally melted on the substrate 21 to form the protrusions 23 , the spacer material will automatically align with the patterned layer 212 due to the formation of the intermetallic compound. Therefore, through the arrangement of the patterned layer 212, the protrusion 23 of self alignment (self alignment) can be formed around the light emitting unit 22, so as to avoid the direct use of mechanical or optical alignment of the protrusion 23 in the known technology. Due to the error generated during setting, it cannot be precisely set around the LED die 321 .

Of course, the above relationship between the protrusions 23 and the patterned layer 212 is only for illustration, and does not limit the materials of the protrusions 23 and the patterned layer 212 . More broadly speaking, the protrusions 23 of this embodiment can form a self-alignment phenomenon on the patterned layer 212, mainly because the adhesion or affinity between the material of the protrusions 23 and the patterned layer 212 is greater than that of the protrusions 23. The adhesion or affinity between the material of the protrusions 23 and the material of the substrate body 211 (or the material around the patterned layer 212) makes the spacer material forming the protrusions 23 adhere to the patterned layer 212 instead of diffusing and overflowing on the patterned layer 212. On the outer surrounding material of the patterned layer 212 .

Taking the circuit board whose material of the substrate 21 is FR-4 as an example, the FR-4 is mainly made of glass fiber mixed with epoxy resin (epoxy), on which a patterned layer and insulating green paint are printed. Since the adhesion of the protrusions 23 to the patterned layer 212 is greater than the adhesion of the protrusions 23 to glass fiber, epoxy resin, or green paint, the protrusions 23 are attached to the patterned layer 212 .

The adhesion between the material of the protrusions 23 and the patterned layer 212 is greater than the adhesion between the material of the protrusions 23 and the substrate body 211, so that the material of the protrusions 23 can be automatically aligned with the patterned layer 212, greatly improving the manufacturing process. efficiency and reduce costs.

Referring to FIG. 2B again, there may be a gap between the protrusions 23 corresponding to two adjacent light emitting units 22 . Of course, in other embodiments, there may be no gap between the protrusions 23 corresponding to two adjacent light emitting units 22 . Wherein, if there is a gap between the protruding object 23 and the adjacent protruding object 23, the stress generated by the protruding object 23 on the substrate 21 is less during the heat reflow process, and the substrate 21 is less likely to warp. And affect product quality.

In addition, an included angle θ is formed between the protrusion 23 and the substrate 21 , and the included angle θ faces the LED die 221 , wherein the included angle θ is larger than 60 degrees. Wherein, the preferred angle of the included angle θ is between 100° and 140°, so that the light emitted by the LED die 221 in the light emitting unit 22 is reflected by the reflective material 24 . If the contact angle (contact angle) between the molten spacer material and the upper surface of the substrate 21 is α, after solidification, the contact angle α is substantially unchanged, and the contact angle α and the included angle θ are substantially complementary angles (∠α+ ∠θ=180°). Since the thickness of the reflective material 24 is relatively thin, the angle θ between the protrusion 23 and the substrate 21 is almost equal to the angle between the protrusion 23 plus the reflective material 24 and the substrate 21 .

In addition, the height of the protrusion 23 may be between 50 micrometers and 800 micrometers, and is greater than the height of the light emitting unit 22 . For example, during flip-chip bonding, the height of the protrusions 23 is about 150 microns; during wire bonding, the height of the protrusions 23 is about 500 microns, so as to prevent the light emitted by each light-emitting unit 22 from interfering with adjacent The problem that the light emitting units 22 interfere with each other.

The reflective material 24 is disposed on the protrusion 23 , here, the reflective material 24 is disposed on the surface of the protrusion 23 and covers the outer surface of the protrusion 23 as an example. Of course, in other embodiments, the reflective material 24 can also be disposed on a part of the surface of the protrusion 23 (eg, the inner surface). The present invention does not limit the reflective material 24 to be disposed on all or part of the surface of the protrusion 23 , as long as it can help to reflect and emit the light emitted by the light emitting unit 22 .

The method of disposing the reflective material 24 on the protrusion 23 may include electroplating, or sticking, or spraying, and the method of disposing the reflective material 24 is not limited here. In addition, the material of the reflective material 24 may include metal, or epoxy resin, or a mixture of titanium dioxide (TiO2) and resin. The metal may include silver, or chromium, or nickel, and this embodiment takes silver as an example. In particular, when the reflective material 24 is provided by electroplating, if there is a gap between two protrusions 23 , it is necessary to connect all the protrusions 23 with conductive wires to facilitate the electroplating process.

Therefore, the present invention arranges the reflective material 24 on the protrusion 23 , so that the light emitted by the LED die 221 can be reflected by the reflective material 24 to improve the light extraction efficiency, thereby improving the light utilization rate of the light emitting device 2 .

In addition, the light emitting device 2 may further include an encapsulation material 25 covering the LED die 221 . Wherein, the packaging material 25 may be doped with fluorescent substances. After the fluorescent substance is excited by the LED die 221 and the light is mixed, the light emitting device 2 can generate a desired color light, such as white light. The protrusion 23 can be higher than the encapsulation material 25 to act as a barrier for the encapsulation material 25. The barrier wall can simplify the manufacturing process and reduce the consumption of the encapsulation material and fluorescent material, further achieving the goal of greatly reducing the production cost.

Based on the above, the light emitting device 2 of the present invention is correspondingly arranged around the light emitting unit 22 through the protrusions 23, thereby, when the light emitting device 2 is used as a display device, it is possible to prevent the light rays from different light emitting units 22 from interfering with each other and causing interference The problem. When the light-emitting device 2 is used as a backlight module, the protrusion 23 can be used as a glue-retaining structure for disposing the packaging material 25 on the LED die 221 , thereby simplifying the manufacturing process and reducing the manufacturing cost. In addition, the reflective material 24 is disposed on the surface of the protrusion 23 so that the light emitted by the LED die 221 can be reflected by the reflective material 24 to improve the light extraction efficiency, thereby improving the light utilization rate of the light emitting device 2 .

In addition, the height of the protrusions can also be adjusted according to the needs of users. Please refer to FIG. 4A , which is a cross-sectional view of another light emitting device 2a.

Different from the light emitting device 2, the height of the protrusion 23a of the light emitting device 2a is smaller than the packaging material 25a. In other words, the packaging material 25a completely covers the light emitting unit 22 and the protrusion 23a. And the height of the protrusion 23a can also be less than or equal to the light emitting unit 22 . Thereby, the protrusion 23a will not affect the light output angle of the light emitting unit 22 due to its high height.

Next, please refer to FIG. 4B , which is a cross-sectional view of another light emitting device 2b.

Different from the light emitting device 2, the light emitting diode die 221 and the protrusions 23 of the light emitting device 2b are disposed on the patterned layer 212b. In addition, the substrate 21 b may also have another patterned layer 213 disposed on the lower surface of the substrate body 211 . In addition, the substrate body 211 can also have at least one through hole O disposed in alignment with the protrusion 23 , and the through hole O connects the patterned layer 212 b and another patterned layer 213 on the lower surface of the substrate body 211 . Wherein, the materials of the patterned layer 212 and the other patterned layer 213 are metals with good thermal conductivity (such as copper). Of course, the through hole O also contains a metal with good thermal conductivity, such as copper.

The arrangement of the patterned layers 212b, 213 and the through hole O can lead the heat generated by the light emitting diode die 211 to another patterned layer 213 on the lower surface of the substrate body 211 through the patterned layer 212b and the through hole O, so that The heat dissipation area is increased to assist the heat dissipation of the LED die 211, thereby improving the service life of the light emitting device 2b. It is worth mentioning that although the LED die 221 is disposed on the patterned layer 212b, it is not electrically connected to the patterned layer 212b, and the circuit layer (not shown) electrically connected to the LED die 221 , it is also disposed on the upper surface or the lower surface of the substrate body 211 . In other embodiments, the LED die 221 can be flip-chip bonded to the substrate 21 and directly disposed on the circuit layer.

Please refer to FIG. 4C to FIG. 4G , which are top views of light emitting devices 2c to 2g according to another aspect of the present invention.

As shown in FIG. 4C , the protrusions 23c of the light emitting device 2c are continuous and correspondingly disposed around each light emitting unit 22 , and are square in shape, and there is a gap between two adjacent protrusions 23c. And the reflective material 24c is disposed on the surface of the protrusion 23c. Certainly, the reflective material 24c may also be provided only on the inner surface of the protrusion 23c.

As shown in FIG. 4D , the protrusions 23d of the light emitting device 2d are discontinuous but respectively arranged around each light emitting unit 22 correspondingly, and there is a gap between two adjacent protrusions 23d. Among them, discontinuous means that the protrusions 23d arranged around each light-emitting unit 22 have disconnected parts. It can be said that there are a plurality of protrusions 23d correspondingly arranged around a light-emitting unit 22, and the reflective material 24d It is provided on the inner side surface of the protrusion 23d.

As shown in FIG. 4E , the protrusions 23 e of the light emitting device 2 e are continuous and correspondingly disposed around each light emitting unit 22 , and are in the shape of a square array, and there is no gap between two adjacent protrusions 23 e. And the reflective material 24e is disposed on the surface of the protrusion 23e. Certainly, the reflective material 24e may also be provided only on the inner surface of the protrusion 23e. Furthermore, the material of the protrusion 23 e can be an electric conductor and is electrically grounded, so as to protect the light emitting unit 22 from static electricity.

As shown in FIG. 4F , different from the light emitting device 2 b in FIG. 4B , each light emitting unit 22 f has two light emitting diode dies 221 respectively. And the reflective material 24f is provided on the surface of the protrusion 23f. Certainly, the reflective material 24f may also be provided only on the inner surface of the protrusion 23f.

In addition, as shown in FIG. 4G, a protrusion 23g of the light-emitting device 2g is continuous and correspondingly arranged around a plurality of light-emitting units 22g, and the shape of the protrusion 23g is square, and the reflective material 24g is arranged on the protrusion. The surface of the object 23g. Certainly, the reflective material 24g may also be only provided on the inner surface of the protrusion 23g. Wherein, each light emitting unit 22g respectively has a plurality of light emitting diode dies 221 arranged in a one-dimensional line. In other words, the light emitting device 2g is a light bar, and the size of the substrate 21 can be cut according to requirements, and can even be as large as the area surrounded by the protrusion 23g. The protrusion 23g can also be used as a retaining wall structure for sealing glue, and can prevent overflow of glue. When a plurality of light-emitting devices 2g are arranged side by side, a large-area light-emitting device can be formed.

In addition, other technical features of the light emitting devices 2 a to 2 g can refer to the light emitting device 2 , which will not be repeated here.

second embodiment

Please refer to FIG. 5 , which is a cross-sectional view of a light emitting device 3 according to a second embodiment of the present invention. In this embodiment, the light emitting device 3 is described by taking a display device as an example.

The main difference between the light emitting device 3 and the light emitting device 2 is that the light emitting diode die 321 of the light emitting device 3 are disposed on the substrate 31 by flip-chip bonding. In addition, the light emitting device 3 may further have a cover plate 36 disposed opposite to the substrate 31 to protect the light emitting unit 32 . Wherein, the cover plate 36 can be a plate (sheet) or a film (film), and can be transparent or partially transparent. In this embodiment, the cover plate 36 is transparent, and may include a fluorescent film or a fluorescent layer (not shown), so that the light emitting device 3 can form a desired color light.

In addition, each light-emitting unit 32 may include three light-emitting diode dies 321 , such as red light, blue light, and green light, which can be mixed to form white light. Of course, the number of LED dies 321 may also be four, for example, two red LED dies 321 are coupled with one green and one blue LED die 321 . Because the size of the light-emitting diode die 321 is relatively small, the size of the light-emitting unit 32 can be greatly reduced, so that the size of the pixel corresponding to the light-emitting unit 32 can be reduced. resolution.

The material of the cover plate 36 may include glass, or sapphire, or quartz, or ceramics, or glass fiber, or resinous material, or polymer material, and other light-transmitting materials. Here, the cover plate 36 is taken as a glass substrate as an example. Therefore, part of the light emitted by the light emitting unit 32 can be reflected by the reflective material 34 and emitted through the cover plate 36 , and the user can view the picture displayed by the light emitting device 3 from the light emitting side of the cover plate 36 .

In addition, in addition to the packaging material 35 , liquid can also be filled between the substrate 31 and the cover plate 36 to increase the thermal conductivity of the light emitting unit 32 , wherein the liquid can be a material with high thermal conductivity. When selecting a liquid, properties such as insulation, corrosion, freezing point, and thermal expansion coefficient should be considered. Here, oils or solvents can be used. Oils such as mineral oil, or silicone oil (Silicone oil) or glycerin (Glycerol), solvents A class such as mesitylene.

In addition, the light emitting device 3 may further include at least one driving component (not shown in the figure) and a bonding glue 37 . The driving component can be disposed on the other side of the substrate 31 opposite to the LED die 321 . The driving component is used to drive the LED die 321 . The driver component includes, for example, a driver integrated circuit (DriverIC). If the driving component is a die, it can be disposed on the substrate 31 by wire bonding or flip chip bonding; if the driving component is a package or a surface bonding component, it can be disposed on the substrate 31 by surface bonding.

The connecting glue 37 can also be called frame glue, which is disposed between the base plate 31 and the cover plate 36 and connects the base plate 31 and the cover plate 36 . The bonding glue 37 can be, for example, an underfill adhesive, and can penetrate between the substrate 31 and the cover plate 36 by capillary phenomenon; of course, the bonding glue 37 can also be coated on the substrate 31 or the cover plate 36, and then the substrate 31 and the cover plate 36 are bonded. The material of the bonding glue 37 includes, for example, silica gel or epoxy resin, so as to protect the light emitting device 3 from the intrusion of moisture or foreign matter and affect its luminous performance and lifespan. It is worth mentioning that if the sealing property of the bonding glue 37 is good, the process of disposing the encapsulation material 35 can also be omitted, so as to reduce the manufacturing process and lower the manufacturing cost.

In addition, other technical features of the light emitting device 3 can refer to the light emitting device 2 , which will not be repeated here.

third embodiment

Please refer to FIG. 6A and FIG. 6B , wherein FIG. 6A is a top view of the light emitting device 4 according to the third embodiment of the present invention, and FIG. 6B is a partially enlarged schematic view of the connection of the substrate 41 of the light emitting device 4 . The light emitting device 4 includes a plurality of substrates 41 and a cover 46 . Each substrate 41 has a plurality of light emitting units 42 . Wherein, the substrate 41 , the light emitting unit 42 , the protrusion 43 , the reflective material 44 , the encapsulation material 45 and the cover plate 46 can refer to the technical features of all the above-mentioned embodiments or the combination of the technical features, and will not be repeated here.

The sides of the substrates 41 can be adjacent to each other or connected to each other (tiling) to form a display device with a large area. When they are adjacent to each other, the substrates 41 can be connected by components (such as frames), or by bonding or snapping. It is spliced with another substrate 41 and then combined with a cover plate 46 to form the light emitting device 4 . Wherein, in addition to using another outer frame to abut and combine the four substrates 41, or another carrier plate (not shown) with a larger area than the substrate 41 can be used to fix the four substrates 41 on the carrier. On the board, the substrate 41 and the cover plate 46 are combined with each other to form a large-area display device, lighting device or backlight. It should be noted that each substrate 41 is a rectangle as an example, but it can also be a circle, an ellipse, other polygons or concave polygons such as jigsaw puzzles, and the carrier board can be made of light-transmitting or opaque material. In addition, the number of substrates 41 is not limited, and there may be different numbers and combinations according to different designs and requirements.

If the two substrates 41 are directly connected, since there is no wiring between the adjacent substrates 41, there will be no seams, which can improve the display quality of the light-emitting device 4, and due to the seamless splicing, when the adjacent substrates 41 During splicing, the light-emitting diodes of the light-emitting units 42 on the respective substrates 41 are dies, so the gap between the light-emitting units 42 can be reduced to 0.3 mm to 1 mm. Therefore, on different substrates 41 , the gap between the two closest light-emitting units 42 can be controlled to be the same as the gap between two adjacent light-emitting units 42 on one of the substrates 41 . Since the light-emitting units 42 are arranged regularly, and the light-emitting units 42 between different substrates 41 at the splicing position also have the same gap, the human eyes cannot see splicing traces, and the quality of the light-emitting device 4 can be improved.

In addition, in this embodiment, the size of the cover plate 46 is larger than the size of the substrate 41. If the light-emitting device 4 is composed of multiple cover plates 46 and multiple substrates 41, the size of the cover plate 46 must be smaller than or equal to the size of one substrate 41. The size is such that the sides of the substrates 41 can be adjacent to each other or connected to each other to form a large-area display device, lighting device or backlight module. In addition, the light emitting device 4 of this embodiment may be spliced in strips or in other shapes besides being spliced in a matrix.

To sum up, according to the light emitting device of the present invention, the protrusions are correspondingly arranged around the light emitting unit, thereby, when the light emitting device is used as a display device, the problem of interference caused by light rays affecting each other between different light emitting units can be avoided . In addition, the protrusion can also be used as a glue-retaining structure for disposing the packaging material on the LED tube core, so as to simplify the manufacturing process and reduce the manufacturing cost. In addition, the reflective material disposed on the protrusion can improve the light output efficiency of the light emitted by the LED tube core through the reflection of the reflective material, thereby improving the light utilization rate of the light emitting device.

In addition, the adhesion between the material of the protrusion and the patterned layer is greater than the adhesion between the material of the protrusion and the substrate body, so that the protrusion can be automatically aligned with the patterned layer (self-align), greatly improving the process efficiency and reduce costs.

The above description is only illustrative, not restrictive. Any equivalent modification or change made without departing from the spirit and scope of the present invention shall be included within the scope defined in the claims.

Claims (16)

1. A lighting device, characterized in that, comprising: At least one substrate has a substrate body and a patterned layer, the patterned layer is disposed on the substrate body; A plurality of light-emitting units are arranged on the substrate, each of the light-emitting units has at least one light-emitting diode die, and the light-emitting diode die is arranged on the substrate and electrically connected to the substrate; At least one protrusion is correspondingly arranged around at least one of the light-emitting units, and the protrusion is substantially aligned with the patterned layer; and A reflective material is disposed on the protrusion. 2 . The light emitting device according to claim 1 , wherein the light emitting diode die is disposed on the substrate by wire bonding or flip chip bonding. 3. The light emitting device according to claim 1, wherein when there are multiple protrusions, there is a gap or no gap between two adjacent protrusions. 4 . The light emitting device according to claim 1 , wherein the protrusions are arranged continuously or discontinuously around each light emitting unit. 5. The light emitting device according to claim 1, wherein the height of the protrusion is greater than that of the light emitting unit. 6 . The light emitting device according to claim 1 , wherein the height of the protrusions is between 50 micrometers and 800 micrometers. 7 . The light emitting device according to claim 1 , wherein the method of disposing the reflective material on the protrusion includes electroplating, or sticking, or spraying. 8. The light emitting device according to claim 1, wherein the reflective material is made of metal, or epoxy resin, or a mixture of titanium dioxide and resin. 9. The lighting device according to claim 1, further comprising: An encapsulation material covers the light-emitting diode die, and the encapsulation material is doped with phosphor. 10. The light-emitting device according to claim 1, wherein the method for arranging the protrusion corresponding to the surrounding of the light-emitting unit comprises: arranging a spacer material correspondingly on the patterned layer and heating, to form the protrusions. 11. The light-emitting device according to claim 10, wherein the spacer material corresponds to the step of being disposed on the patterned layer by screen printing, or printing, or coating, or inkjet process, or directly place. 12. The light emitting device according to claim 1, wherein the material of the protrusion comprises metal, metal oxide, resin or silica gel. 13. The light emitting device according to claim 1, wherein the height of the protrusion is smaller than that of the packaging material. 14. The light emitting device according to claim 1, wherein the height of the protrusion is smaller than or equal to the light emitting unit. 15. The light emitting device according to claim 1, wherein the protrusion forms an included angle with the substrate, and the included angle is greater than 60 degrees. 16. The lighting device according to claim 1, further comprising: A cover plate is arranged opposite to the base plate, the cover plate is transparent and includes a fluorescent film or a fluorescent layer.

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