Light emitting device and method for manufacturing the same

By preforming annular grooves on the substrate of the light emitting device and forming the shape of the packaging material by using surface tension, the problem of difficult control of the shape of the packaging material in the prior art is solved, and the packaging effect with simple structure and low cost is achieved.

JP7674548B2Active Publication Date: 2025-05-09CITIZEN ELECTRONICS CO LTD +1
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Patent Information

Application Number
JP2024022247
Authority / Receiving Office
JP · JP
Patent Type
Patents
Current Assignee / Owner
Filing Date
2024-02-16
Publication Date
2025-05-09
Estimated Expiration
2040-03-09

AI Technical Summary

Technical Problem

When existing light emitting devices encapsulate light emitting elements, it is difficult to control the shape of the packaging material through a simple structure, and the structure is complex and costly.

Method used

By preforming annular grooves on the substrate of the light emitting device, the encapsulation material is placed at the boundary of the light emitting region using surface tension, thereby forming the encapsulation material of the desired shape.

Benefits of technology

The shape of the packaging material is controlled through a simple structure, reducing equipment complexity and cost, while improving the shape control accuracy of the packaging material.

✦ Generated by Eureka AI based on patent content.

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Patent Text Reader

Abstract

To provide a light-emitting device and manufacturing method therefor, capable of controlling a shape of a sealing material formed in a light-emitting region.SOLUTION: A light-emitting device includes: a light-emitting element; a packaging substrate with a groove part formed to surround the light-emitting element; and a sealing material which is arranged on a light-emitting region surrounded by the groove part to come into contact with a boundary between the light-emitting region and the groove part and seals the light-emitting element.SELECTED DRAWING: Figure 1
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Description

[Technical field]

[0001] The present invention relates to a light emitting device and a method for manufacturing the same. [Background technology]

[0002] Light-emitting devices in which light-emitting elements such as LEDs (Light-Emitting Diodes) are mounted on a substrate are used as light sources for display devices such as liquid crystal displays or lighting devices such as ceiling lights. For example, the display devices described in Patent Documents 1 and 2 include a light source in which a light-emitting element is mounted on a substrate for mounting a light-emitting element, the substrate being an enamel substrate with a reflective recess, which can be efficiently and inexpensively produced as an enamel substrate with a reflective recess.

[0003] The package structure of the light-emitting element described in Patent Documents 1 and 2, as shown in FIG. 3, uses a package having a cone-shaped reflective recess with an electrode partially extending into the reflective recess, a light-emitting element such as an LED is mounted on one electrode in the reflective recess of this package, the light-emitting element and the other electrode are electrically connected by a gold wire, and a sealing resin is filled into the reflective recess so that the upper part is raised and hardened to form a lens shape. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2006-303359 A [Patent Document 2] JP 2008-193113 A Summary of the Invention [Problem to be solved by the invention]

[0005] As described in Patent Documents 1 and 2, the light-emitting element of the light-emitting device is usually sealed and protected by a sealing resin. In order to form the sealing resin in a predetermined light-emitting region, the light-emitting region is made into a cone shape lower than the surrounding area, or a dam material is formed to surround the light-emitting region so that the sealing resin does not flow out of the light-emitting region. However, simply making the light-emitting region into a cone shape makes it difficult to fix the sealing resin in a desired shape. Furthermore, forming a dam material to surround the light-emitting region complicates the structure of the light-emitting device, resulting in high costs.

[0006] SUMMARY OF THE PRESENT DISCLOSURE In view of the above, an object of the present invention is to provide a light emitting device that is capable of controlling the shape of a sealing material formed in a light emitting region with a simple structure, and a method for manufacturing the same. [Means for solving the problem]

[0007] One embodiment of the light emitting device according to the present invention is characterized in that it comprises a light emitting element, a mounting substrate having a groove portion formed to surround the light emitting element, and a sealing material that is disposed on the light emitting area so as to contact the boundary between the light emitting area surrounded by the groove portion and the groove portion, thereby sealing the light emitting element.

[0008] In the above light emitting device, it is preferable that the mounting substrate has a first groove portion formed to surround the first light emitting element and a second groove portion formed to surround the second light emitting element, and the sealing material includes a first sealing material arranged on the first light emitting region so as to contact the boundary between the first groove portion and the first light emitting region surrounded by the first groove portion and seals the first light emitting element, and a second sealing material arranged on the second light emitting region so as to contact the boundary between the second groove portion and the second light emitting region surrounded by the second groove portion and seals the second light emitting element. The first light emitting region emits light of a first color, and the second light emitting region emits light of a second color different from the first color.

[0009] In the above light emitting device, it is preferable that the mounting substrate further has a third groove portion formed so as to surround both the first groove portion and the second groove portion, and the sealing material further includes a third sealing material disposed on the third light emitting region so as to contact the boundary between the third groove portion and the third light emitting region surrounded by the third groove portion, thereby further sealing both the first light emitting region and the second light emitting region, and that the third sealing material contains a diffuser that diffuses the first color light and the second color light.

[0010] The above light emitting device further comprises a circuit board arranged on the side of the mounting board on which the light emitting element is mounted, a wire electrically connecting the light emitting element to a power supply terminal formed on the circuit board, a frame formed to surround both the first light emitting region and the second light emitting region, and a third sealing material arranged on the region surrounded by the frame to seal the wire, the first light emitting region, and the second light emitting region, and it is preferable that the third sealing material contains a diffuser that diffuses the first color light and the second color light.

[0011] In the above light emitting device, it is preferable that the groove portion includes a plurality of grooves formed along a first direction and a plurality of grooves formed along a second direction perpendicular to the first direction.

[0012] In the above light-emitting device, it is preferable that the light-emitting elements are arranged in a ring shape on the mounting substrate, the groove portion includes a first groove formed to surround the multiple light-emitting elements arranged in a ring shape from the outer periphery side and a second groove formed to surround them from the inner periphery side, and the sealing material is arranged in a ring shape on the light-emitting region so as to contact the boundary between the light-emitting region surrounded by the first groove and the second groove and the boundary between the light-emitting region and the second groove, thereby sealing the multiple light-emitting elements.

[0013] The above light emitting device preferably further comprises a lens having a ring-shaped recess arranged so as to cover the ring-shaped sealant, for converging or diverging light emitted from the sealant.

[0014] A manufacturing method for a light emitting device according to one embodiment of the present invention is characterized in that it includes forming a groove portion on a surface of a mounting substrate, mounting a light emitting element in a light emitting area surrounded by the groove portion, and arranging a sealant on the light emitting area using surface tension so that the sealant contacts the boundary between the light emitting area and the groove portion, thereby sealing the light emitting element.

[0015] In the above-mentioned method for manufacturing a light emitting device, it is preferable that forming the groove portion includes forming a first groove portion and a second groove portion on a surface of the mounting substrate, mounting the light emitting element includes mounting the first light emitting element in a first light emitting region surrounded by the first groove portion and mounting the second light emitting element in a second light emitting region surrounded by the second groove portion, sealing the first light emitting element by placing a first sealing material on the first light emitting region using surface tension so as to contact the boundary between the first light emitting region and the first groove portion, and sealing the second light emitting element by placing a second sealing material on the second light emitting region using surface tension so as to contact the boundary between the second light emitting region and the second groove portion, and the first light emitting region emits light of a first color and the second light emitting region emits light of a second color different from the first color.

[0016] In the above-mentioned method for manufacturing a light-emitting device, forming the groove portion further includes forming a third groove portion so as to surround both the first groove portion and the second groove portion, and sealing the light-emitting element includes disposing a third sealant on the third light-emitting region by utilizing surface tension so as to contact the boundary between the third groove portion and the third light-emitting region surrounded by the third groove portion, thereby further sealing both the first light-emitting region and the second light-emitting region, and it is preferable that the third sealant contains a diffuser that diffuses the first color light and the second color light.

[0017] In the above-mentioned method for manufacturing a light emitting device, it is preferable that forming the groove portion includes forming a plurality of grooves along a first direction and forming a plurality of grooves along a second direction perpendicular to the first direction.

[0018] In the above-described method for manufacturing a light emitting device, it is preferable that forming the groove portion includes performing half dicing in a direction tangent to the boundary between the light emitting region and the groove portion. Effect of the Invention

[0019] According to the present invention, a light emitting device capable of controlling the shape of a sealing material formed in a light emitting region with a simple structure and a manufacturing method thereof are provided. [Brief description of the drawings]

[0020] [Figure 1] FIG. 1 is a diagram illustrating a schematic configuration of a light emitting device according to a first embodiment of the present invention. [Figure 2A] 2A to 2C are diagrams illustrating an example of a method for manufacturing the light emitting device illustrated in FIG. [Figure 2B] 2A to 2C are diagrams illustrating an example of a method for manufacturing the light emitting device illustrated in FIG. [Diagram 3] FIG. 13 is a schematic showing an encapsulant self-formed on a light-emitting region by surface tension. [Figure 4] FIG. 4 is a diagram illustrating a schematic configuration of a light emitting device according to a second embodiment of the present invention. [Diagram 5] FIG. 13 is a diagram illustrating a schematic configuration of a light emitting device according to a third embodiment of the present invention. [Figure 6] FIG. 13 is a diagram illustrating a schematic configuration of a light emitting device according to a fourth embodiment of the present invention. [Figure 7] FIG. 13 is a diagram illustrating a schematic configuration of a light emitting device according to a fifth embodiment of the present invention. [Figure 8A] 8A to 8C are diagrams illustrating an example of a method for manufacturing the light emitting device illustrated in FIG. 7. [Figure 8B] 8A to 8C are diagrams illustrating an example of a method for manufacturing the light emitting device illustrated in FIG. 7. [Figure 9] FIG. 13 is a diagram illustrating a schematic configuration of a light emitting device according to a sixth embodiment of the present invention. [Figure 10] FIG. 13 is a diagram illustrating a modified example of the configuration of the light emitting device according to the sixth embodiment of the present invention. [Figure 11] FIG. 13 is a diagram illustrating a schematic configuration of a light emitting device according to a seventh embodiment of the present invention. [Figure 12] FIG. 13 is a diagram illustrating a modified example of the configuration of the light emitting device according to the seventh embodiment of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0021] The light-emitting device of the present invention is characterized in that, in the process of forming a sealing resin in a light-emitting region in which a light-emitting element is mounted, the sealing material is arranged in the light-emitting region so that the step between the light-emitting region surrounded by the groove portion and the groove portion forms the boundary.

[0022] As a result, in the light-emitting device according to the present invention, simply by forming a groove of a desired shape in advance on the mounting substrate, the sealing material placed on the light-emitting region surrounded by the groove will self-form into the desired shape due to surface tension. Therefore, in the light-emitting device according to the present invention, it is not necessary to make the light-emitting region into a cone shape lower than the surrounding area or to form a dam material to surround the light-emitting region, simplifying the structure of the light-emitting device.

[0023] Hereinafter, preferred embodiments of the present invention will be described with reference to the drawings. Note that the present invention is not limited to the following embodiments, and can be modified as appropriate without departing from the spirit of the present invention. In addition, in each drawing, parts having the same or corresponding functions are given the same reference numerals, and their description may be omitted or simplified.

[0024] (First embodiment) 1 is a diagram showing a schematic configuration of a light emitting device 1 according to a first embodiment of the present invention. The upper and lower parts of the diagram show a plan view of the configuration of the light emitting device 1 and a cross-sectional view taken along line AA thereof, respectively.

[0025] The light emitting device 1 is supplied with power from an external power source (not shown) via a cable or the like to emit light. The light emitting device 1 is used, for example, as a light source for a display device such as a liquid crystal display, or an illumination device such as a ceiling light. Although the light emitting device 1 shown in FIG. 1 has a rectangular planar shape, the shape of the light emitting device 1 may be appropriately determined depending on the application, and may be, for example, a polygonal or circular shape. The light emitting device 1 has a mounting substrate 2 and a light emitting element 4.

[0026] The mounting substrate 2 is formed of a material having high insulating properties and thermal conductivity mainly made of ceramics or resin, for example, a glass epoxy substrate (FR-4) or a glass composite substrate (CEM-3). The mounting substrate 2 has flat light-emitting regions 20a-20d on which light-emitting elements 4 such as LEDs are mounted. By directly disposing the light-emitting elements 4 on the light-emitting regions 20a-20d, heat generated in the light-emitting elements 4 is efficiently dissipated by being conducted through the mounting substrate 2 having high thermal conductivity. The planar shape of the light-emitting regions 20a-20d is determined by the shape of the grooves 21a-21d formed so as to surround the light-emitting regions 20a-20d. For example, in FIG. 1, the light-emitting regions 20a-20d have a circular shape surrounded by the ring-shaped grooves 21a-21d, respectively. Note that the grooves 21a-21d may be formed in a closed path so as to surround the light-emitting elements 4, and may be formed of a plurality of linear grooves as shown in FIG. 7 described later, in addition to the ring shape shown in FIG. 1. 1, adjacent groove portions 21a-21d share a portion of the groove, but groove portions 21a-21d may be independent of each other without sharing a groove. Mounting substrate 2 may have one to three or five or more light emitting regions in addition to four light emitting regions 20a-20d as shown in FIG.

[0027] The mounting substrate 2 is provided with power supply terminals 23a to 23d penetrating the mounting substrate 2. The power supply terminals 23a to 23d supply positive and negative potentials supplied from the rear surface side of the mounting substrate 2 via cables or the like to the light emitting elements 4. The power supply terminals 23a to 23d are formed, for example, by filling a metal such as gold or copper into a through hole provided on the mounting substrate 2, and then arranging metal contacts or metal wiring on the front and rear surfaces of the region where the metal is filled. As a result, power is supplied to the light emitting elements 4 from the rear surface side of the mounting substrate 2, so there is no need to provide a circuit board or the like on the mounting substrate 2, and the structure of the light emitting device 1 is simplified.

[0028] The light emitting element 4 is, for example, a LED die mounted on the light emitting region 20 of the mounting substrate 2 by die bonding or the like, and then the cathode terminal and the anode terminal of the LED are electrically connected to the power supply terminals 23a to 23d by wires 5 or the like. The light emitting element 4 emits light when positive and negative potentials are supplied from an external power source via the power supply terminals 23a to 23d and the wires 5. A Zener diode or the like may be connected in parallel between the power supply terminals 23a, 23c and the power supply terminals 23b, 23d to prevent an overvoltage from being applied to the light emitting element 4. Note that the multiple light emitting elements 4 shown in FIG. 1 are arranged so that their sides face each other, but the light emitting elements 4 may be rotated 45 degrees and arranged so that their vertices face each other. The light emitting element 4 is preferably arranged so that its upper surface is parallel to the surface of the mounting substrate 2. The light emitting element 4 emits visible light such as purple, blue, green, red, etc., but may also include invisible light such as infrared light, or a combination of these.

[0029] The sealing materials 6a and 6b seal the light emitting regions 20a to 20d surrounded by the grooves 21a to 21d to protect the light emitting element 4 and the wire 5. The sealing materials 6a and 6b are made of a resin such as epoxy or silicone that is transparent to the light emitted by the light emitting element 4. For example, in FIG. 1, the sealing material 6a (first sealing material) is disposed on the light emitting regions 20a and 20c so as to contact the boundaries between the light emitting regions 20a and 20c (first light emitting regions) and the grooves 21a and 21c (first grooves). In addition, the sealing material 6b (second sealing material) is disposed on the light emitting regions 20b and 20d so as to contact the boundaries between the light emitting regions 20b and 20d (second light emitting regions) and the grooves 21b and 21d (second grooves). In the plan view of FIG. 1, the light emitting element 4 and the wire 5 sealed by the sealing materials 6a and 6b are shown by solid lines instead of dashed lines for convenience.

[0030] The sealing materials 6a and 6b may contain a phosphor that converts the light emitted by the light-emitting element 4 into light with a longer wavelength. The phosphor may be, for example, a particulate phosphor material such as YAG (Yttrium Aluminum Garnet) that absorbs the blue light emitted by the light-emitting element 4 and emits yellow light. As a result, the blue light emitted by the light-emitting element 4 and the yellow light whose wavelength has been converted by the phosphor are mixed to obtain white light. The sealing materials 6a and 6b may contain a phosphor that converts the blue light into a color other than yellow light, such as red light or green light. The intensity of the first color light emitted from the light-emitting regions 20a and 20c covered by the sealing material 6a is adjusted by controlling the value of the current flowing to the light-emitting element 4 via the power supply terminals 23a and 23c. Similarly, the intensity of the second color light emitted from the light-emitting regions 20b and 20d covered by the sealing material 6b is adjusted by controlling the value of the current flowing to the light-emitting element 4 via the power supply terminals 23b and 23d.

[0031] Figures 2A and 2B are diagrams that roughly show one example of a method for manufacturing the light emitting device 1 shown in Figure 1. The upper and lower parts of the figures respectively show a plan view of the configuration of the light emitting device 1 and a cross-sectional view taken along line AA thereof.

[0032] First, as shown in FIG. 2A, the grooves 21a to 21d are formed in a closed path on the surface of the mounting substrate 2. The ring-shaped grooves 21a to 21d are formed by, for example, half-dicing using a laser process, but may also be formed by half-dicing using a blast process or by half-dicing using a rotary polishing tool. In this case, the grooves 21a to 21d may be formed by moving the laser or rotary polishing tool relative to the fixed mounting substrate 2, or conversely, the grooves 21a to 21d may be formed by moving the mounting substrate 2 relative to the fixed laser or rotary polishing tool. The size of the grooves 21a to 21d is, for example, 0.2 mm in width and 0.1 mm in depth. The shape of the grooves 21a to 21d does not necessarily have to be ring-shaped as shown in FIG. 2A, as long as they are formed in a closed path. The width of the grooves 21a to 21d does not necessarily have to be constant, and may vary depending on the location.

[0033] In addition, when the width of the grooves 21a to 21d is wide, it is also possible to perform half dicing in a plurality of times to form the grooves 21a to 21d. For example, a plurality of narrow grooves may be arranged and connected to form one wide groove 21a. Alternatively, particularly when the groove 21a is formed by laser processing, a plurality of small-diameter circular holes may be arranged two-dimensionally and connected to form the groove 21a. In this case, if half dicing is performed in a direction perpendicular to the boundary surface at the boundary between the light-emitting region 20a and the groove 21a, unevenness will be generated at the step of the boundary surface, and when the sealing material 6a is filled, it will be easy for the sealing material 6a to flow from the light-emitting region 20a to the groove 21a. As a result, it will be difficult to arrange the sealing material 6a on the light-emitting region 20b by utilizing surface tension so that the sealing material 6a will contact the boundary with the groove 21a. Therefore, it is preferable that half dicing is performed in a direction contacting the boundary at the boundary between the light-emitting region 20a and the groove 21a.

[0034] 2B, the light emitting element 4 is mounted in the light emitting regions 20a-20d surrounded by the grooves 21a-21d by die bonding or the like. Then, the cathode terminal and the anode terminal of the light emitting element 4 are electrically connected to the power supply terminals 23a-23d formed on the mounting substrate 2 by wires 5 or the like. The size of the light emitting element 4 is, for example, 0.65 mm on a side in a plan view and 0.2 mm in height in a cross-sectional view.

[0035] Then, as shown in FIG. 1, the sealant 6a (first sealant) is disposed on the light emitting regions 20a and 20c by utilizing surface tension so as to contact the boundaries between the light emitting regions 20a and 20c (first light emitting regions) and the grooves 21a and 21c (first grooves), respectively. Also, the sealant 6b (second sealant) is disposed on the light emitting regions 20b and 20d by utilizing surface tension so as to contact the boundaries between the light emitting regions 20b and 20d (second light emitting regions) and the grooves 21b and 21d (second grooves), respectively. As a result, the sealant 6a is self-formed on the light emitting regions 20a and 20c by surface tension, and the sealant 6b is self-formed on the light emitting regions 20b and 20d by surface tension. Then, the light emitting device 1 shown in FIG. 1 is manufactured.

[0036] 3(a) and 3(b) are schematic diagrams showing the sealing material 6 that is self-formed on the light-emitting region 20 by surface tension. The sealing material 6 formed by utilizing surface tension is fixed on the light-emitting region 20 so that the position of the outer edge of the sealing material 6 roughly coincides with the position of the step at the boundary between the light-emitting region 20 and the groove 21, as shown in FIG. 3(a). In the process of forming this sealing resin in the light-emitting region 20, parameters such as the viscosity of the sealing material 6 and the amount of liquid filled in the light-emitting region 20 are adjusted according to the shape of the groove 21.

[0037] For example, when a highly viscous sealant 6 is filled onto the light-emitting region 20, the sealant 6 tends to have a large surface tension and become spherical, as shown in Fig. 3(b). Such a highly viscous sealant 6 is suitable for sealing a circular light-emitting region 20 surrounded by a ring-shaped groove 21 as shown in Fig. 1.

[0038] On the other hand, when a sealant 6 with low viscosity is filled onto the light-emitting region 20, the surface tension of the sealant 6 is small and the sealant 6 is unlikely to become spherical, as shown in Fig. 3(c). Such a sealant 6 with low viscosity is suitable for sealing a rectangular light-emitting region 20 surrounded by a groove portion 21 composed of a plurality of linear grooves, as shown in Fig. 7 described later.

[0039] In this way, the light-emitting device 1 of the present invention is characterized in that, in the process of forming a sealing resin in the light-emitting region 20, the sealing material 6 is arranged in the light-emitting region 20 so that the step between the light-emitting region 20 surrounded by the groove portion 21 and the groove portion 21 forms the boundary.

[0040] As a result, in light emitting device 1 according to the present invention, simply by forming groove 21 of a desired shape in mounting substrate 2 beforehand, sealing material 6 arranged on light emitting region 20 surrounded by groove 21 will self-form into the desired shape due to surface tension. Therefore, in light emitting device 1 according to the present invention, there is no need to make light emitting region 20 into a cone shape lower than its surroundings or to form a dam material to surround light emitting region 20, and the structure of light emitting device 1 is simplified.

[0041] Second embodiment Fig. 4 is a diagram showing a schematic configuration of a light emitting device 1 according to a second embodiment of the present invention. The upper and lower parts of the figure show a plan view of the configuration of the light emitting device 1 and a cross-sectional view taken along line AA thereof, respectively. In addition to the light emitting device 1 shown in Fig. 1, the light emitting device 1 shown in Fig. 4 further includes a sealant 6 (third sealant) formed so as to cover the sealants 6a and 6b. As the rest of the configuration is generally the same as the light emitting device 1 according to the first embodiment shown in Fig. 1, differences from the light emitting device 1 according to the first embodiment will be described below.

[0042] In the mounting substrate 2 of the light emitting device 1 shown in FIG. 4, a groove portion 21 (third groove portion) is formed in a closed path so as to surround all of the light emitting regions 20a to 20d.

[0043] The sealing material 6 is disposed on the light emitting region 20 so as to be in contact with the boundary between the light emitting region 20 (third light emitting region) surrounded by the groove portion 21 and the groove portion 21, and further seals the light emitting regions 20a to 20d. The sealing material 6 may contain a diffuser that diffuses the first color light emitted from the light emitting regions 20a and 20c and the second color light emitted from the light emitting regions 20b and 20d. The diffuser does not necessarily need to be uniformly contained in the sealing material 6, but may be contained at least in the upper surface layer portion in the sealing material 6. This allows the sealing material 6 to diffuse the first color light and the second color light different from the first color light by the diffuser and mix them. For example, the first color light is a cool white light with a color temperature of 3000K to 4000K, and the second color light is a warm white light with a color temperature of 5000K to 6000K. Alternatively, the first color light is blue light with a wavelength of 400 nm to 500 nm, and the second color light is yellow light with a wavelength of 550 nm to 600 nm.

[0044] Third embodiment 5 is a diagram showing a schematic configuration of a light emitting device 1 according to a third embodiment of the present invention. The upper and lower parts of the figure show a plan view of the configuration of the light emitting device 1 and a cross-sectional view taken along line AA thereof, respectively. The light emitting device 1 shown in FIG. 5 differs from the light emitting device 1 shown in FIG. 4 mainly in that it has only one light emitting region 20 surrounded by a groove portion 21. As the rest of the configuration is generally the same as the light emitting device 1 according to the second embodiment shown in FIG. 4, the differences from the light emitting device 1 according to the second embodiment will be described below.

[0045] The light-emitting elements 4 mounted on the light-emitting region 20 are electrically connected to each other by wires 5 to form one row. For example, in FIG. 5, two light-emitting elements 4 are connected in series to one row, but the number of light-emitting elements 4 connected to one row may be appropriately determined depending on the voltage supplied from the external power source. For example, when a voltage of 6V is supplied from the external power source, two light-emitting elements 4 having a light-emitting voltage of 3V are connected in series to form one row. The light-emitting elements 4 located at both ends of each row are electrically connected to the power supply terminals 23a, 23b via the wires 5.

[0046] The encapsulant 6 may contain a phosphor that converts the light emitted by the light-emitting element 4 into light with a longer wavelength. The intensity of the first color light emitted from the light-emitting region 20 covered by the encapsulant 6 is adjusted by controlling the value of the current flowing to the light-emitting element 4 via the power supply terminals 23a and 23b.

[0047] Even in the case of the light emitting device 1 that emits monochromatic light with such a simple configuration, the shape of the sealing material 6 formed in the light emitting region 20 can be controlled by the shape of the groove portion 21.

[0048] (Fourth embodiment) Fig. 6 is a diagram showing a schematic configuration of a light emitting device 1 according to a fourth embodiment of the present invention. The upper and lower parts of the figure show a plan view of the configuration of the light emitting device 1 and a cross-sectional view taken along line AA thereof, respectively. The light emitting device 1 shown in Fig. 6 differs from the light emitting device 1 shown in Fig. 1 mainly in that the mounting substrate 2 has a ring-shaped light emitting region 20 and that a lens 8 is disposed so as to cover this light emitting region 20. As the rest of the configuration is generally the same as the light emitting device 1 according to the first embodiment shown in Fig. 1, the differences from the light emitting device 1 according to the first embodiment will be described below.

[0049] In the light emitting device 1 shown in Fig. 6, a plurality of light emitting elements 4 are arranged in a ring shape on a mounting substrate 2. The groove portion includes a first groove 21e and a second groove 21f, the first groove 21e is formed so as to surround the plurality of light emitting elements 4 arranged in a ring shape from the outer periphery side, and the second groove 21f is formed so as to surround the plurality of light emitting elements 4 arranged in a ring shape from the inner periphery side. The sealing material 6 is arranged in a ring shape on the light emitting region 20 so as to contact the boundary between the light emitting region 20 surrounded by the first groove 21e and the second groove 21f and the first groove 21e, and the boundary between the light emitting region 20 and the second groove 21f, thereby sealing the plurality of light emitting elements 4.

[0050] As a result, a surface light source that irradiates light in a ring shape can be obtained with a simple structure in which a groove portion including the first groove 21e and the second groove 21f is formed. Compared to a linear light source that irradiates light in a straight line, this surface light source is less likely to change color when viewed from an oblique direction, and color directivity is improved.

[0051] 6 further includes a lens 8 that collects or diverges light emitted from the ring-shaped light-emitting region 20. The lens 8 includes a recess 80 having a ring-shaped planar shape, and is disposed so as to cover the ring-shaped sealing material 6, and refracts the light emitted from the sealing material 6 to collect or diverge the light.

[0052] As shown in Fig. 6, the ring width of the ring-shaped light-emitting region 20 is as narrow as the line width of the linear light source, so even though the light-emitting device 1 shown in Fig. 6 is a surface light source, it is possible to reduce the recess 80 of the lens 8 covering the ring-shaped light-emitting region 20. Therefore, the lens 8 shown in Fig. 6 has a simpler structure and is smaller in size than a lens having a configuration in which a plurality of recesses respectively cover a plurality of light-emitting elements 4 arranged two-dimensionally on the mounting substrate 2.

[0053] Fifth embodiment Fig. 7 is a diagram showing a schematic configuration of a light emitting device 1 according to a fifth embodiment of the present invention. The upper and lower parts of the figure show a plan view of the configuration of the light emitting device 1 and a cross-sectional view taken along line AA thereof, respectively. The light emitting device 1 shown in Fig. 7 differs from the light emitting device 1 shown in Fig. 1 mainly in that the groove portions 21a and 21b are composed of a plurality of linear grooves. As the rest of the configuration is generally the same as the light emitting device 1 according to the first embodiment shown in Fig. 1, the differences from the light emitting device 1 according to the first embodiment will be described below.

[0054] The mounting substrate 2 has flat light-emitting regions 20a, 20b on which light-emitting elements 4 such as LEDs are mounted. The light-emitting regions 20a, 20b have a rectangular shape surrounded by grooves 21a, 21b, respectively. In FIG. 7, the adjacent grooves 21a, 21b share a portion of the groove, but the grooves 21a, 21b may be independent of each other without sharing the groove. The mounting substrate 2 may have one or more light-emitting regions in addition to the two light-emitting regions 20a, 20b as shown in FIG. 7.

[0055] The sealing materials 6a and 6b seal the light-emitting regions 20a and 20b surrounded by the grooves 21a and 21b, respectively, to protect the light-emitting element 4. For example, in FIG. 7, the sealing material 6a (first sealing material) is disposed on the light-emitting region 20a so as to be in contact with the boundary between the light-emitting region 20a (first light-emitting region) and the groove 21a (first groove portion). Also, the sealing material 6b (second sealing material) is disposed on the light-emitting region 20b so as to be in contact with the boundary between the light-emitting region 20b (second light-emitting region) and the groove 21b (second groove portion). In the plan view of FIG. 7, the light-emitting element 4 and the wire 5 sealed by the sealing materials 6a and 6b are shown by solid lines instead of dashed lines for convenience.

[0056] In this way, even when the grooves 21a, 21b are composed of a plurality of linear grooves and the light-emitting regions 20a, 20b surrounded by the grooves 21a, 21b have a rectangular shape, the same effects as those of the light-emitting device 1 of the first embodiment can be obtained.

[0057] Figures 8A and 8B are diagrams that roughly show one example of a method for manufacturing the light emitting device 1 shown in Figure 7. A plan view and a perspective view of the configuration of the light emitting device 1 are shown at the top and bottom, respectively. Below, the points that differ from the method for manufacturing the light emitting device 1 of the first embodiment will be described.

[0058] First, as shown in Fig. 8A, a plurality of grooves 21g are formed along a first direction d1 on the surface of the mounting substrate 2. The linear grooves 21g as shown in Fig. 8A can be easily formed by, for example, half-dicing with a rotary polishing tool, but may also be formed by, for example, half-dicing with laser processing.

[0059] 8B, a plurality of grooves 21h are formed on the surface of the mounting substrate 2 along a second direction d2 perpendicular to the first direction d1. As a result, groove portions 21a and 21b each consisting of a plurality of grooves 21g and a plurality of grooves 21h are formed so as to surround the light emitting regions 20a and 20b, respectively. The size of the grooves 21g and 21h is, for example, 0.2 mm in width and 0.1 mm in depth.

[0060] 2A and 2B, the light emitting device 1 shown in Fig. 7 is manufactured by substantially the same steps as the manufacturing method described with reference to Fig. 2A and 2B. The groove portions 21a-21d composed of such a plurality of linear grooves 21g, 21h can be formed by a simpler process than the ring-shaped groove portions 21a-21d.

[0061] Sixth embodiment Fig. 9 is a diagram showing a schematic configuration of a light emitting device 1 according to a sixth embodiment of the present invention. The upper and lower parts of the figure show a plan view of the configuration of the light emitting device 1 and a cross-sectional view taken along line AA thereof, respectively. The light emitting device 1 shown in Fig. 9 differs from the light emitting device 1 shown in Fig. 7 mainly in that a circuit board 3 is disposed on the front side of a mounting substrate 2, and the light emitting element 4 is electrically connected to power supply terminals 31a to 31d of the circuit board 3. As the rest of the configuration is generally the same as the light emitting device 1 according to the fifth embodiment shown in Fig. 7, the differences from the light emitting device 1 according to the fifth embodiment will be described below.

[0062] The light emitting device 1 shown in FIG. 9 includes a circuit board 3 in addition to a mounting board 2 and a light emitting element 4.

[0063] The circuit board 3 is formed of a resin having high insulating properties, mainly made of a resin such as phenol, epoxy, polyimide, or polyester. The circuit board 3 is disposed in an area outside the light emitting areas 20a to 20d of the mounting board 2. For example, the circuit board 3 shown in FIG. 9 has a circular opening, and is attached to the mounting board 2 so that the light emitting elements 4 mounted in the light emitting areas 20a to 20d are exposed from the opening. The power supply terminals 31a to 31d are formed on the circuit board 3. The power supply terminals 31a to 31d supply positive and negative potentials supplied from an external power source via a cable or the like to the light emitting elements 4. The power supply terminals 31a to 31d are formed by patterning a metal such as gold or copper on the circuit board 3. The power supply terminals 31a to 31d may be further protected by being covered with a solder resist or the like, which is an insulating film.

[0064] The mounting board 2 shown in FIG. 9 does not have the power supply terminals 23a-23d penetrating the mounting board 2 as shown in FIG. 1. Therefore, the mounting board 2 may be formed of a highly conductive material mainly made of a metal such as aluminum or copper, in addition to a highly insulating material mainly made of ceramics or resin. The mounting board 2 has light emitting areas 20a-20d surrounded by grooves 21a-21d. In FIG. 9, the adjacent grooves 21a-21d share a part of the groove, but the grooves 21a-21d may be independent of each other without sharing the groove. The mounting board 2 may have one to three or five or more light emitting areas in addition to the four light emitting areas 20a-20d as shown in FIG. 9.

[0065] The light emitting elements 4 are electrically connected to each other by wires 5 to form one row. For example, in FIG. 9, five light emitting elements 4 are connected in series in one row, but the number of light emitting elements 4 connected to one row may be appropriately determined depending on the voltage supplied from an external power source, etc. The light emitting elements 4 located at both ends of each row are electrically connected to the power supply terminals 31a to 31d via wires 5. In this way, by arranging many light emitting devices 1 in each of the light emitting regions 20a to 20d, the intensity of the light emitted from each of the light emitting regions 20a to 20d is improved.

[0066] The sealing materials 6a and 6b may contain a phosphor that converts the wavelength of the light emitted by the light-emitting element 4 into light with a longer wavelength. The intensity of the first color light emitted from the light-emitting regions 20a and 20c covered with the sealing material 6a is adjusted by controlling the value of the current passed through the light-emitting element 4 via the power supply terminals 31a and 31c. Similarly, the intensity of the second color light emitted from the light-emitting regions 20b and 20d covered with the sealing material 6b is adjusted by controlling the value of the current passed through the light-emitting element 4 via the power supply terminals 31b and 31d.

[0067] The sealing material 6 is arranged so as to further cover the light-emitting regions 20a to 20d. The sealing material 6 may contain a diffuser that diffuses the first color light emitted from the light-emitting regions 20a and 20c and the second color light emitted from the light-emitting regions 20b and 20d. In that case, as shown in FIG. 9, when the amount of the sealing material 6 is large and it is difficult to maintain the sealing material 6 in a desired shape due to the surface tension of the sealing material 6, the sealing material 6 may be held by a frame 7. The frame 7 is formed by arranging a continuous body of a dam material or the like in a ring or rectangular shape so as to surround the opening of the circuit board 3. The frame 7 is formed of, for example, a silicon resin or an epoxy resin. The frame 7 is preferably formed of a white resin in which fine particles such as titanium oxide that easily reflect light are dispersed. As a result, the light emitted from the light-emitting element 4 is reflected upward in the light-emitting device 1, thereby improving the utilization efficiency of the light emitted from the light-emitting element 4.

[0068] The grooves 21a to 21d may have a shape that combines a linear groove and a ring-shaped groove, as shown in Fig. 10. In this case, parameters such as the viscosity of the sealing material 6 and the amount of liquid filled in the light-emitting region 20 are adjusted according to the shape of the grooves 21, as described in Fig. 3.

[0069] 9 and 10, by disposing the sealing material 6 (third sealing material) on the area surrounded by the frame body 7, the wire 5 and the light emitting element 4 connected to the wire 5 are completely sealed and protected. Even in this case, the sealing materials 6a and 6b (first sealing material and second sealing material) are formed without the frame body 7, so the structure of the light emitting device 1 is simplified. Furthermore, compared to the sealing material 6 held by the frame body 7 using surface tension as shown in FIG. 4, it is easier to incorporate a diffuser that diffuses light into the sealing material 6 held by the frame body 7, so the manufacturing method of the light emitting device 1 is simplified.

[0070] Seventh embodiment FIG. 11 is a diagram showing a schematic configuration of a light-emitting device 1 according to a seventh embodiment of the present invention. The upper and lower parts of the figure show a plan view of the configuration of the light-emitting device 1 and a cross-sectional view along line AA thereof, respectively. The light-emitting device 1 shown in FIG. 11 has only one light-emitting region 20 surrounded by a groove 21, similar to the light-emitting device 1 of the third embodiment shown in FIG. 5. Even in the case of a light-emitting device 1 that irradiates monochromatic light with such a simple configuration, the shape of the sealing material 6 formed in the light-emitting region 20 can be controlled by the shape of the groove 21. Furthermore, as shown in FIG. 12, a plurality of light-emitting devices 1 may be combined to form an aggregate substrate 1b for manufacturing a plurality of light-emitting devices 1.

[0071] As described above, a light emitting device according to an embodiment of the present invention is characterized by having a light emitting element, a mounting substrate having a groove formed to surround the light emitting element, and a sealant disposed on the light emitting region so as to contact the boundary between the light emitting region surrounded by the groove and the groove, thereby providing a light emitting device and a method for manufacturing the same that are capable of controlling the shape of the sealant formed in the light emitting region with a simple structure.

[0072] The above-mentioned embodiments are merely examples of the implementation of the present invention, and the technical scope of the present invention should not be interpreted as being limited by them. In other words, the present invention can be implemented in various forms without departing from its technical concept or main features. For example, the configurations of the above-mentioned embodiments can be implemented in combination. [Explanation of symbols]

[0073] 1 Light emitting device 2. Mounting Board 20, 20a-20d Light-emitting area 21, 21a~21d groove 21e~21h Groove 22 Through hole 23a~23d, 31a~31d Power supply terminals 3 Circuit Board 4 Light emitting element 5 Wire 6, 6a~6b Encapsulating material 8 Lenses 80 Recess

Claims

1. A plurality of light emitting elements including a first light emitting element and a second light emitting element; a mounting substrate having a first light-emitting region on which the first light-emitting element is mounted, a second light-emitting region on which the second light-emitting element is mounted, a first groove portion formed to entirely surround the periphery of the first light-emitting region, a second groove portion formed to entirely surround the periphery of the second light-emitting region, and a terminal for supplying electricity to the light-emitting element; a first sealing material disposed on the first light-emitting region so as to be in contact with a boundary between the first groove portion and a first light-emitting region surrounded by the first groove portion, and sealing the first light-emitting element; a second sealing material disposed on the second light-emitting region so as to be in contact with a boundary between the second light-emitting region surrounded by the second groove portion and the second groove portion, and sealing the second light-emitting element; a plurality of wires connecting the plurality of light-emitting elements or connecting the light-emitting elements and the terminals; At least one of the plurality of wires is disposed so as to straddle either the first groove portion or the second groove portion; The first light-emitting region emits light of a first color, and the second light-emitting region emits light of a second color different from the first color; Both the first encapsulant and the second encapsulant encapsulate at least one of the plurality of wires. A light emitting device characterized by:

2. a third sealing material that seals the wire, the first light-emitting region, and the second light-emitting region; The light emitting device of claim 1 , wherein the third encapsulant contains a diffuser that diffuses the first color light and the second color light.

3. The light-emitting device further includes a frame body formed to surround both the first light-emitting region and the second light-emitting region, The third sealing material is disposed on a region surrounded by the frame. The light emitting device according to claim 2 .

4. The light emitting device according to claim 3 , wherein the third encapsulant encapsulates all of the plurality of wires.

5. 5. The light emitting device according to claim 1, wherein each of the first groove portion and the second groove portion includes a plurality of grooves formed along a first direction and a plurality of grooves formed along a second direction perpendicular to the first direction.

6. a terminal for supplying electricity to a plurality of light-emitting elements including a first light-emitting element and a second light-emitting element, a first light-emitting region in which the first light-emitting element is mounted, a second light-emitting region in which the second light-emitting element is mounted, a first groove portion formed so as to entirely surround the periphery of the first light-emitting region, and a second groove portion formed so as to entirely surround the periphery of the second light-emitting region; The first light emitting element is mounted in the first light emitting region; The second light emitting element is mounted in the second light emitting region; A plurality of wires are used to connect the plurality of light emitting elements and between the plurality of light emitting elements and the terminals; a first sealing material is disposed on the light emitting region by utilizing surface tension so as to be in contact with a boundary between the first light emitting region and the first groove portion, thereby sealing the first light emitting element; a second sealing material is disposed on the light emitting region by utilizing surface tension so as to be in contact with a boundary between the second light emitting region and the second groove portion, thereby sealing the first light emitting element; disposing a third encapsulant to encapsulate the wire, the first light emitting region, and the second light emitting region; At least one of the plurality of wires is disposed so as to straddle either the first groove portion or the second groove portion; The first light-emitting region emits light of a first color, and the second light-emitting region emits light of a second color different from the first color; A method for manufacturing a light emitting device, wherein both of the first sealing material and the second sealing material seal at least one of the plurality of wires over an entirety.

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