CN110260182B - light emitting device - Google Patents

Abstract

The invention discloses a light-emitting device, comprising a carrier plate with a first surface and a second surface opposite to the first surface, and a light-emitting unit arranged on the first surface, which emits light toward but does not pass through first surface. The light-emitting device can measure a first luminance above the first surface, and can measure a second luminance below the second surface. The ratio of the first luminance to the second luminance is 2-9.

Description

light emitting device

This application is a divisional application of a Chinese invention patent application (application number: 201510438508.4, application date: July 23, 2015, invention name: light emitting device).

technical field

The invention relates to a light emitting device, in particular to a light emitting device with an optical structure.

Background technique

Light-emitting diodes (Light-Emitting Diodes; LEDs) used in solid-state lighting devices have the characteristics of low energy consumption, long life, small size, fast response, and stable optical output. Therefore, light-emitting diodes are slowly replacing traditional lighting products and are being used. Applied to general household lighting.

In recent years, the filaments made of light-emitting diodes have been gradually used in light-emitting diode bulbs. However, the cost and efficiency of LED filaments still need to be improved. Furthermore, it is still a development goal to make the light emitting diode filament emit an omnidirectional light field and deal with the heat dissipation problem.

Contents of the invention

In order to make the above and other objects, features and advantages of the present invention more comprehensible, the following specific embodiments are described below together with the accompanying drawings.

A light-emitting device includes a carrier plate with a first surface and a second surface opposite to the first surface, and a light-emitting unit arranged on the first surface that emits light toward but not through the first surface. The light-emitting device can measure a first brightness above the first surface, and can measure a second brightness below the second surface. The ratio of the first brightness to the second brightness is 2-9.

Description of drawings

FIG. 1A is a three-dimensional schematic diagram of a light emitting device in an embodiment of the present invention;

FIG. 1B is a schematic top view of the carrier plate in FIG. 1A;

Figure 1C is a schematic bottom view of the carrier plate in Figure 1A;

Figure 1D is a schematic cross-sectional view of Figure 1A and along the line BI-I of Figure 1;

FIG. 1E is a schematic cross-sectional view of FIG. 1A;

Figure 1F is an enlarged view of Figure 1E;

2A to 2D are schematic diagrams of different travel paths of light emitted by the light emitting unit in the optical structure;

FIG. 2E is a light distribution curve diagram of a light emitting device in an embodiment of the present invention;

3A is a schematic cross-sectional view of a light emitting unit in an embodiment of the present invention;

3B is a schematic cross-sectional view of a light emitting unit in another embodiment of the present invention;

Figure 3C is a top view of Figure 3B;

3D is a schematic cross-sectional view of a light emitting unit in another embodiment of the present invention;

FIG. 4 is a three-dimensional schematic diagram of a light bulb in an embodiment of the present invention;

FIG. 5A is a flow chart of manufacturing a light-emitting device in an embodiment of the present invention;

5B-5E are three-dimensional schematic views of the manufacturing process of the light emitting device in an embodiment of the present invention.

Symbol Description

100 lighting fixtures

10 Optical structure

101 top surface

102 side surface

103 side bottom surface

1031 part one

1032 part two

104 bottom surface

11 carrier board

111 upper surface

112 lower surface

12, 12A, 12B, 12D light emitting unit

120A first connection pad

120B Second connection pad

121 Luminous subject

1211 electrodes

122 The first transparent body

123 phosphor layer

124 Second transparent body

125, 125' third transparent body

1251 Part I

1251S side surface

1252 part two

1253 plane

1254 Inclined

126 insulating layer

127 Extension electrodes

129 reflective structures

13 circuit structure

131 First electrode pad

132 Second electrode pad

133, 1331, 1331A, 1332, 1332B Conductive lines

134 Third electrode pad

135 fourth electrode pad

151 First through hole

152 Second through hole

21 stand

211 frame

30 bulbs

301 lamp housing

302 circuit board

303 support column

304 radiator

305 electrical connector

307 electrode parts

308, 309 metal wire

Detailed ways

The following embodiments will illustrate the concept of the present invention with accompanying drawings. In the drawings or descriptions, similar or identical parts use the same symbols, and in the drawings, the shape or thickness of elements can be enlarged or reduced. It should be noted that components not shown or described in the figure may be in the form known to those skilled in the art.

FIG. 1A shows a perspective view of a light emitting device 100 in an embodiment of the present invention. FIG. 1B only shows a schematic top view of the carrier 11 in FIG. 1A . FIG. 1C only shows a schematic bottom view of the carrier 11 in FIG. 1A . FIG. 1D shows a schematic cross-sectional view of FIG. 1A along line BI-I of FIG. 1 . FIG. 1E shows a schematic cross-sectional view of FIG. 1A along the YZ direction. Referring to FIGS. 1A-1E , the light emitting device 100 includes an optical structure 10 , a carrier 11 , and a plurality of light emitting units 12 . The carrier board 11 has an upper surface 111 and a lower surface 112 . A circuit structure 13 is formed on the upper surface 111 and has a first electrode pad 131 , a second electrode pad 132 and a conductive circuit 133 . The light emitting units 12 are disposed on the conductive lines 133 on the upper surface 111 and connected in series through the conductive lines 133 . In other embodiments, the light emitting units 12 may be connected in parallel, in series or in parallel, or in a bridge structure through other designs of the conductive lines 133 . In this embodiment, the carrier board 11 is not penetrated (opaque) by the light emitted by the light emitting unit 12 , so even though the light emitting unit 12 emits light toward the upper surface 111 , it does not pass through the upper surface 111 . The carrier board 11 can be a circuit board. The core layer of the circuit board includes metal, thermoplastic material, thermosetting material, or ceramic material. Metals include alloys, stacks, or single layers of aluminum, copper, gold, silver, etc. The thermosetting material includes phenolic resin (Phonetic), epoxy resin (Epoxy), bismaleimide triazine resin (BismaleimideTriazine) or a combination thereof. The thermoplastic material includes polyimide resin, polytetrafluoroethylene and the like. Ceramic materials include alumina, aluminum nitride, silicon carbide, and the like.

As shown in FIG. 1A, FIG. 1B and FIG. 1C, a reflective layer 14 is formed on the upper surface 111 and the circuit structure 13, and only exposes the conductive lines 1331, 1332 and the electrode pads 131, 132 to be electrically connected to the light emitting unit 12. The conductive circuit 1331 and the conductive circuit 1332 are physically separated from each other. In this embodiment, the conductive circuit 1332A is physically separated from the electrode pad 131 and the conductive circuit 1331B is physically separated from the electrode pad 132 . Each light emitting unit 12 includes a first connection pad 120A and a second connection pad 120B respectively physically and electrically connected to the exposed conductive lines 1331 and 1332 . In this embodiment, the exposed conductive circuits 1331 , 1332 are rectangular and their long sides are parallel to the long sides of the carrier board 11 . In another embodiment, the long sides of the exposed conductive circuits 1331 and 1332 are parallel to the short sides of the carrier 11 , or form an angle between 0° and 90° with the long sides. Alternatively, the exposed conductive lines 1331, 1332 can be circular, elliptical, or polygonal. In addition, the configuration of the reflective layer 14 can help to reflect the light emitted from the light emitting unit 12 toward the carrier 11 to increase the overall luminous efficiency of the light emitting device 100 .

As shown in FIG. 1C and FIG. 1D , the light emitting unit 12 is not disposed on the lower surface 112 . The circuit structure 13 further includes a third electrode pad 134 and a fourth electrode pad 135 formed on the lower surface 112 of the carrier 11 . The third electrode pad 134 and the fourth electrode pad 135 correspond to the positions of the first electrode pad 131 and the second electrode pad 132 respectively. A first through hole 151 runs through the carrier plate 11 and has a conductive substance formed therein completely or partially to electrically connect the first electrode pad 131 and the third electrode pad 134 . A second through hole 152 runs through the carrier plate 11 and has a conductive substance formed therein completely or partially to electrically connect the second electrode pad 132 and the fourth electrode pad 135 . In one embodiment, an external power supply is respectively connected to the first electrode pad 131 and the second electrode pad 132 to make the plurality of light emitting units 12 emit light. The third electrode pad 134 and the fourth electrode pad 135 may not be directly physically connected to an external power source. When the electrode pads 131, 132 are electrically connected to the external power source by means of electric welding (butt welding), since a metal clip is required to clamp the carrier plate 11, the arrangement of the electrode pads 134, 135 can help clamp the light emitting device 100 during the manufacturing process. stability and provide a conductive path. In one embodiment, when the electrode pads 131 , 132 are electrically connected to an external power source by using bonding wires, the third electrode pad 134 and the fourth electrode pad 135 may not be formed.

As shown in FIG. 1A and FIG. 1E , the optical structure 10 covers the upper surface 111, the lower surface 112 and the sidewalls 113 on both sides of the long side of the carrier 11, but exposes the electrode pads 131, 132, 134, 135. . The optical structure 10 has a rectangular cross-section. Figure 1F is an enlarged view of Figure 1E. The optical structure 10 has a curved top surface 101 ; two substantially linear side surfaces 102 parallel to each other; two bottom surfaces 103 ; and a substantially planar bottom surface 104 connecting the two bottom surfaces 103 . The top surface 101 is located above the upper surface 111 of the carrier board 11 , and the bottom surface 104 is located below the lower surface 112 of the carrier board 11 . The side surface 102 extends from the top surface 101 to the bottom surface 112 of the carrier 11 along the Z direction. Each side bottom surface 103 includes a first portion 1031 extending from the side surface 102 to the bottom surface 104 at an inclined angle; and a second portion 1302 . The second portions 1302 on the left and right sides in the figure are respectively connected to the first portion 1031 and extend toward the bottom surface 104 in an arc shape. The lower surface 112 of the carrier plate 11 is separated from the bottom surface 104 of the optical structure 10 by a first distance D1 between 0.3 mm and 0.7 mm; A second distance D2 of 0.13mm. The second distance D2 is greater than the first distance D1. The arc of the top surface 101 has a radius of curvature ranging from 0.4 mm to 0.7 mm, and has an arc angle θ1 (central angle corresponding to the arc) ranging from 40° to 60° or an arc ranging from 2π/9 ~π/3. The arc of the second part of the side bottom surface 103 has a radius of curvature between 0.2-0.4 mm, and has an arc angle θ2 (central angle corresponding to the arc) between 5°-20° or an arc between π/36～π/9. A diffusing powder (such as titanium dioxide, zirconium oxide, zinc oxide or aluminum oxide) can be selectively filled into the optical structure 10 to help diffuse and scatter the light emitted by the light emitting unit 12 . The weight percent concentration (w/w) of the diffusing powder in the optical structure 10 is 0.1-0.5% and has a particle size of 10-100 nm or 10-50 μm. In one embodiment, the powder concentration by weight of the diffusing powder in the colloid can be measured by a thermogravimetric analyzer (TGA). Briefly, during the heating process, the colloid will be removed (evaporated or thermally cracked) due to the gradual increase in temperature and after reaching a certain temperature, and the diffusion powder will remain. At this time, the change in weight can be known, so it can be obtained The respective weights of the colloid and the diffusing powder are calculated to obtain the weight percent concentration of the diffusing powder in the colloid. Alternatively, the total weight of the colloid and the diffusing powder can be measured first, then the colloid can be removed with a solvent, and finally the weight of the diffusing powder can be measured to obtain the weight percent concentration of the diffusing powder in the colloid. In FIG. 1A , although the light emitting unit 12 can be seen. However, when the diffusion powder is filled into the optical structure 10 and reaches a certain concentration, the optical structure 10 will appear white and the light-emitting unit 12 inside cannot be seen.

The optical structure 10 is transparent to sunlight or the light emitted by the light emitting unit 12 . The optical structure 10 includes silica gel (Silicone), epoxy resin (Epoxy), polyimide (PI), benzocyclobutene (BCB), perfluorocyclobutane (PFCB), SU8, acrylic resin (Acrylic Resin), Polymethyl methacrylate (PMMA), polyethylene terephthalate (PET), polycarbonate (PC), polyetherimide (Polyetherimide), fluorocarbon polymer (Fluorocarbon Polymer), alumina ( Al ₂ O ₃ ), SINR, or spin-on-glass (SOG).

FIG. 2A shows a schematic diagram of the path of the light emitted by the light emitting unit 12 traveling in the optical structure 10 . It should be noted that the path in the attached figure is only one of many possible paths, and it is not the only path, the same below. For example, when the light L from the light emitting unit 12 hits the arc-shaped top surface 101 , the light L will generate a first refracted light L11 and a first reflected light L12 on the top surface 101 . The first reflected light L12 strikes the side surface 102 , and generates the second refracted light L21 and the second reflected light L22 on the side surface 102 . The second reflected ray L22 strikes the bottom surface 104 , and generates a third refracted ray L31 and a third reflected ray L32 on the bottom surface 104 . Or, as shown in FIG. 2B , for example, the light M from the light emitting unit 12 hits the arc-shaped top surface 101 , and the light M will generate a first refracted light M11 and a first reflected light M12 on the top surface 101 . The first reflected light M12 strikes the first portion 1031 of the side bottom surface 103 , and the second refracted light M21 and the second reflected light M22 are generated in the first portion 1031 . The second reflected ray M22 strikes the bottom surface 104 , and generates a third refracted ray M31 and a third reflected ray M32 on the bottom surface 104 . FIG. 2C and FIG. 2D show schematic diagrams of other possible travel paths of light in the optical structure 10 . The shape design of the optical structure 10 of the present invention increases the probability of light emitting from the lower surface 112 of the carrier 10 and the probability of light emitting from the bottom surface 104 . The light-emitting device 100 can measure a first luminance above the upper surface 111 (first side), and can measure a second luminance below the lower surface 112 (second side). The ratio of the first luminance to the second luminance is between between 2 and 9. The definition of the first brightness and the second brightness can refer to the subsequent description. It should be noted that the path in the figure is only one of many possible paths, not the only path. In addition, in the above description, the light is refracted and reflected on the surface at the same time. However, the light may also be merely refracted or reflected on the surface, depending on the difference in refractive index at the material interface, the angle of incidence, the wavelength of the light, etc.

FIG. 2E shows a light distribution curve obtained when the light emitting device 100 is operated at a current of 10 mA and is in a thermal steady state. In detail, when the light emitting device 100 emits light, the luminous brightness of an imaginary circle (such as circle P1 in FIG. 1A ) can be measured by using a light distribution curve meter. Further, a light distribution curve can be obtained by plotting the luminous brightness and the angle. During measurement, the geometric center of the light emitting device 100 is approximately located at the center of the circle P1. In this embodiment, the weight percent concentration of the diffusing powder in the optical structure 10 is 0.3%. As shown in the figure, the maximum luminance of the light emitting device 100 is about 4.53 cd, and the luminance from 0 degree to 180 degree roughly presents a lambertian distribution. Specifically, the brightness at -90 degrees is the smallest and is about 0.5 candlepower (cd), the brightness from -90 degrees to -80 degrees is roughly the same, and the brightness from -80 degrees to 90 degrees increases gradually. The curve of -90 to 0 to 90 degrees is roughly similar to the curve of 90 to 180 to -90 degrees, and the distribution of light intensity at -90 to 0 to 90 degrees is opposite to the distribution of light intensity at 90 to 180 to -90 degrees Axisymmetric to a straight line at 90 to -90 degrees. In addition, the total brightness of 0-90-180 degrees in the light distribution curve is defined as the first brightness, and the total brightness of 0-90--180 degrees is defined as the second brightness, the ratio of the first brightness to the second two degrees about 4. From the light distribution curve, it can be calculated that the light emitting angle of the light emitting device 100 is about 160 degrees.

Lighting angle, which is defined as when the brightness is 50% of the maximum brightness, the angle range included at this time is the lighting angle. For example: first convert the light distribution curve (polar coordinates) measured on the P1 circle in Figure 2E into a rectangular coordinate graph to obtain a brightness curve; wherein, the X-axis is the brightness, and the Y-axis is the angle (Fig. not shown). Then, draw a straight line parallel to the X-axis at about 2.265 candlepower (50% of the maximum brightness) and intersect the brightness curve at two points; calculate the angle range between the two points, which is defined as the luminous angle.

FIG. 3A shows a schematic cross-sectional view of a light emitting unit 12A in an embodiment of the present invention. The light emitting unit 12A includes a light emitting body 121 , a first transparent body 122 , a phosphor layer 123 , a second transparent body 124 and a third transparent body 125 . The light-emitting body 121 includes a substrate, a first-type semiconductor layer, an active layer, a second-type semiconductor layer (not shown above) and two electrodes 1211 . When the light-emitting body 121 is a heterostructure, the first-type semiconductor layer and the second-type semiconductor layer are, for example, cladding layers and/or confinement layers, which can respectively provide electrons and holes and have One is larger than the energy gap of the active layer, thereby increasing the probability of combining electrons and holes in the active layer to emit light. The first-type semiconductor layer, the active layer, and the second-type semiconductor layer may comprise III-V group semiconductor materials, such as Al _x In _y Ga _(1-xy) N or Al _x In _y Ga _(1-xy) P, wherein 0≦x,y≦1; (x+y)≦1. According to the material of the active layer, the light-emitting body 121 can emit a red light with a peak wavelength or a dominant wavelength between 610nm and 650nm, a green light with a peak or dominant wavelength between 530nm and 570nm, or It is blue light with peak or dominant wavelength between 450nm and 490nm. The phosphor structure 123 includes a plurality of phosphor particles. The phosphor particles have a particle size (diameter) of about 5 um˜100 um and may contain one or more than two types of phosphor materials. Phosphor materials include, but are not limited to, yellow-green phosphors and red phosphors. The composition of the yellow-green phosphor is, for example, aluminum oxide (YAG or TAG), silicate, vanadate, alkaline earth metal selenide, or metal nitride. Components of red phosphor such as fluoride (K ₂ TiF ₆ :Mn ⁴⁺ , K ₂ SiF ₆ :Mn ⁴⁺ ), silicate, vanadate, alkaline earth metal sulfide, metal oxynitride, or tungstomolybdic acid Salt mixture. The phosphor structure 123 can absorb the first light emitted by the light-emitting body 121 and convert it into a second light with a spectrum different from the first light. The mixing of the first light and the second light will generate a mixed light, such as white light. In this embodiment, the light generated by the light emitting unit 12 in a thermal steady state has a white color temperature of 2200K-6500K (for example: 2200K, 2400K, 2700K, 3000K, 5700K, 6500K), and its color point value (CIE x, y ) will fall within the range of seven MacAdam ellipses (MacAdam ellipse), and have a color rendering (CRI) greater than 80 or greater than 90. In another embodiment, the mixing of the first light and the second light can generate purple light, yellow light or other non-white light.

The light-emitting unit 12 also includes an insulating layer 126 formed on the first transparent body 122, a phosphor layer 123 and two electrodes 1211 below the second transparent body 124 and not covering the light-emitting body 121; and two extension electrodes 127 are respectively formed on the two electrodes 1211 and is electrically connected to the two electrodes 1211. The two extension electrodes 127 are respectively used as the aforementioned first connection pad 120A and a second connection pad 102B (as shown in FIG. 1D ). The insulating layer 126 is a mixture including a matrix and a material with high reflectivity. The matrix can be either a silicone matrix or an epoxy matrix. High reflectivity materials may include titanium dioxide, silicon dioxide or aluminum oxide. In addition, the insulating layer 126 may have a function of reflecting light or diffusing light. The extension electrodes 127 include metals, such as copper, titanium, gold, nickel, silver, alloys thereof, or stacks thereof. The first transparent body 122 , the second transparent body 124 and the third transparent body 125 are transparent to sunlight or light emitted by the light emitting unit 12 . The first transparent body 122 or the second transparent body 124 may include silica gel (Silicone), epoxy resin (Epoxy), polyimide (PI), benzocyclobutene (BCB), perfluorocyclobutane (PFCB), SU8, acrylic resin (Acrylic Resin), polymethyl methacrylate (PMMA), polyethylene terephthalate (PET), polycarbonate (PC), polyetherimide (Polyetherimide), fluorocarbon polymerization Fluorocarbon Polymer, Aluminum Oxide (Al ₂ O ₃ ), SINR, or Spin On Glass (SOG). The third transparent body 125 may include sapphire (Sapphire), diamond (Diamond), glass (Glass), epoxy resin (Epoxy), quartz (quartz), acrylic resin (Acrylic Resin), silicon oxide (SiO _x ), aluminum oxide (Al ₂ O ₃ ), zinc oxide (ZnO), or silica gel (Silicone).

As shown in FIG. 3A , the third transparent body 125 has a shape that is wide at the top and narrow at the bottom. In detail, the third transparent body 125 has a first part 1251 and a second part 1252 . The second portion 1252 is closer to the second transparent body 124 and has a width smaller than that of the first portion 1251 . The thickness of the first part 1251 is about 1%-20% or 1%-10% of the overall thickness of the third transparent body 125 . In this embodiment, the junction of the first portion 1251 and the second portion 1252 is an arc. The first part 1251 has a side surface 1251S, which is slightly inclined upward (facing upward), and is farther away from the light-emitting body 121 than the side surface 1241 of the second transparent body 124 , and can guide light to both sides of the light-emitting unit 12 .

In one embodiment, the light emitting unit 12A is a light emitting structure that emits light toward five sides (upper, left, right, front, back) and has a beam angle of about 140 degrees. Optionally, a diffusing powder can be added to the first transparent body 122 , or/and the second transparent body 124 , or/and the third transparent body 125 . In another embodiment, the light emitting unit 12A does not include the third transparent body 125 .

FIG. 3B shows a schematic cross-sectional view of the light emitting unit 12B in another embodiment of the present invention. Fig. 3C is a top view of Fig. 3B. The light-emitting unit in FIG. 3B is similar to the light-emitting device in FIG. 3A , and components or devices corresponding to the same symbols or marks have similar or identical components or devices. As shown in FIG. 3B , the third transparent body 125' has a frustum shape and has a flat surface 1253 and an inclined surface 1254. The design of the slope 1254 can increase the light extraction amount of the light emitting body 121 and change the light field of the light emitting unit 12 . The plane 1253 and the inclined surface 1254 can form an angle Φ between 120°˜150° and the depth H1 of the inclined surface 1254 is 30%˜70% or 40%˜60% of the overall thickness H2 of the third transparent body 125′. As shown in FIG. 3C , the area (A1; triangle) of the plane 1253 may be 40%-95% or 40%-60% of the total projected area (A; oblique line) of the third transparent body 125'.

FIG. 3D shows a schematic cross-sectional view of a light emitting unit 12D in another embodiment of the present invention. The light-emitting unit in FIG. 3D is similar to the light-emitting device in FIG. 3A , and components or devices corresponding to the same symbols or marks have similar or identical components or devices. The light emitting unit 12D further includes a reflective structure 129 formed between the first transparent body 124 and the second transparent body 125 . The reflective structure 129 has a reflectivity greater than 85% when the light incident on the reflective structure 129 is in the wavelength range of 450nm-475nm; reflectivity. Light that is not reflected by the reflective structure 129 can enter the third transparent body 125 and leave the light emitting unit 12D or the third transparent body 125 through the top or side of the third transparent body 125 . If the reflective structure 129 can reflect most of the light, for example, the reflectivity is greater than 95%, then the third transparent body 125 in the light emitting unit 12D can be omitted. The reflective structure 129 can be a single-layer structure or a multi-layer structure. The single-layer structure is, for example, a metal layer, including, for example, silver or aluminum, or an oxide layer, including, for example, titanium dioxide. The multilayer structure can be a stack of metal and metal oxide or a distributed Bragg reflector (Distributed Bragg reflector, DBR) to achieve the effect of reflection. Lamination of metal and metal oxide such as lamination of aluminum and aluminum oxide. DBRs can be non-semiconductor stacks or semiconductor stacks. The material of the non-semiconductor stack may be selected from one of the following groups: aluminum oxide (Al ₂ O ₃ ), silicon oxide (SiO ₂ ), titanium dioxide (TiO ₂ ), niobium pentoxide (Nb ₂ O ₅ ), nitride Silicon ( _SiNx ). The material of the semiconductor stack may be selected from one of the following groups: gallium nitride (GaN), aluminum gallium nitride (AlGaN), aluminum indium gallium nitride (AlInGaN), aluminum arsenide (AlAs), aluminum gallium arsenide ( AlGaAs), gallium arsenide (GaAs). In this embodiment, no matter whether it is a single-layer structure or a multi-layer structure, the light will not be completely reflected, so at least part of the light will directly pass through the reflective structure 129 .

In another embodiment, the light-emitting unit 12 in FIG. 1A may have a structure similar to the light-emitting units 12A, 12B, and 12D in FIG. 3A , FIG. 3B , or FIG. 3D , but the phosphor layer 123 is not included in the structure. That is, the light emitting unit 12 only emits the original light from the light emitting body 121 , such as red light, green light, or blue light. A plurality of phosphor particles (wavelength conversion substances) can be added in the optical structure 10 to absorb the first light emitted by the light-emitting body 121 and convert it into a second light with a spectrum different from the first light. The first light and the second light Blending produces white light. Therefore, the light-emitting device 100 can have a white light color temperature of 2200K-6500K (for example: 2200K, 2400K, 2700K, 3000K, 5700K, 6500K) in a thermal steady state, and its color point value (CIE x, y) will fall in seven MacAdam ellipse (MacAdam ellipse) range, and have a color rendering (CRI) greater than 80 or greater than 90.

The light emitting unit of this embodiment is formed on the carrier board in a flip-chip manner. In other embodiments, a plurality of horizontal or vertical light-emitting units (not shown) can be fixed on the carrier board with silver glue or conductive transparent glue; then, the light-emitting units are electrically connected to each other by wire bonding; Finally, an optical structure is provided to cover the light-emitting unit to form a light-emitting device.

FIG. 4 shows a perspective view of a light bulb 30 in an embodiment of the present invention. The light bulb 30 includes a lamp housing 301 , a circuit board 302 , a support column 303 , a plurality of light emitting devices 100 , a heat sink 304 , and an electrical connector 305 . A plurality of light emitting devices 100 are fixed and electrically connected to the support column 303 . In detail, an electrode member 307 is formed on the support column 303 and electrically connected to the circuit board 302 . The third electrode pad 134 of each light emitting device 100 is connected to the circuit board 302 through a metal wire 308 . Since the first electrode pad 131 is electrically connected to the third electrode pad 134 , the first electrode pad 131 is also electrically connected to the circuit board 302 . The second electrode pad 132 of each light emitting device 100 is connected to the electrode member 307 through a metal wire 309 . In this embodiment, the light emitting devices 100 are connected in parallel with each other through the above-mentioned electrical connection manner. In other embodiments, the light emitting devices 100 may be connected in series or in parallel.

FIG. 5A shows a flow chart of the fabrication of the light-emitting device of the present invention. As shown in FIG. 5A and FIG. 5B , step 501 : providing a bracket 21 . The bracket 21 has two frames 211 and a plurality of carrier boards 11 connected between the two frames 211 . There is a circuit structure 13 on the carrier board 11 , and the circuit structure 13 can be formed before or after forming the bracket 21 and the carrier board 11 . For example, if the bracket 21 and the carrier 11 are formed on a single sheet by stamping technology, the circuit structure 13 can be preformed on the single sheet first, or formed on the carrier 11 after the stamping step. As shown in FIG. 5A and FIG. 5C , step 502 : fix the light-emitting units 12 on the carrier board 11 by surface bonding technology (SMT), and electrically connect the light-emitting units 12 to each other through the circuit structure 13 . As shown in FIG. 5A and FIG. 5D, step 503: use a molding method, such as: injection molding (injection molding) or transfer molding (transfer molding) to form an optical structure 10, so that it covers the light emitting unit 12 and the carrier plate 11 and Only the electrode pads 131, 132 are exposed. Step 504 as shown in FIG. 5A and FIG. 5E : perform a punching or laser cutting process to separate the carrier 11 and the two frames 211 , thereby forming multiple independent light emitting devices 100 at the same time or at one time.

It should be understood that the above-mentioned embodiments in the present invention can be combined or replaced with each other under appropriate circumstances, and are not limited to the specific embodiments described. The various embodiments listed in the present invention are only used to illustrate the present invention, and are not intended to limit the scope of the present invention. Any obvious modification or change made by anyone to the present invention will not depart from the spirit and scope of the present invention.

Claims (9)

1. A lighting device, characterized in that it comprises: A first carrier plate comprising a metal material, a flat upper surface, and a lower surface opposite to the upper surface, the upper surface having a first portion and a second portion extending from the first portion; a plurality of light-emitting units, arranged on the second part, not electrically connected to the first carrier, and completely overlapping the upper surface in a top view; a first electrode pad, disposed on the first part, electrically connected to the plurality of light emitting units; a conductive circuit, located on the first carrier, electrically connected to at least one of the plurality of light emitting units and the first electrode pad; a first reflective layer on the conductive line; and an optical structure comprising a wavelength converting substance disposed on the second portion and exposing the first portion, wherein, in the top view, the first portion is wider than the second portion, Among them, the optical structure includes: a top surface located above the upper surface; a bottom surface located below the lower surface; a side surface extending from both ends of the top surface toward the lower surface; and a side bottom surface comprising a first portion and a second portion, the first portion of the side bottom surface extending from the side surface toward the bottom surface at an oblique angle, And the second portion of the side bottom surface is connected to the first portion and extends toward the bottom surface in an arc shape. 2. The light-emitting device according to claim 1, wherein when the light-emitting device is in operation, the first brightness can be measured above the upper surface, and the second brightness can be measured below the lower surface, and the first brightness and The ratio of the second brightness is between 2-9. 3. The light emitting device as claimed in claim 1, wherein the first carrier further comprises a third portion extending from the second portion and not covered by the optical structure. 4. The light emitting device as claimed in claim 1, wherein the first electrode pad is not covered by the optical structure. 5. The light emitting device as claimed in claim 1, further comprising a second electrode pad, the second electrode pad and the first electrode pad are located on the same surface of the first carrier. 6. The light-emitting device according to claim 1, further comprising a second reflective layer, the second reflective layer and the plurality of light-emitting units are respectively located on opposite sides of the first carrier. 7. The light emitting device according to claim 1, wherein each of the plurality of light emitting units has a light emitting body and a reflective structure on the light emitting body. 8. The light emitting device according to claim 7, further comprising a transparent structure covering the reflective structure. 9 . The light emitting device according to claim 7 , wherein each of the plurality of light emitting units has positive and negative electrodes, and the positive and negative electrodes and the reflective structure are respectively located on opposite sides of the light emitting body.

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