JP2017059787A - Light-emitting module - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a light-emitting module with improved light-emitting efficiency.SOLUTION: A light-emitting module 10 comprises an insulating substrate 15, a plurality of semiconductor light-emitting elements 16, a metal conductor 17, a metal wire 18, a phosphor sealing part 19, and a transparent sealing part 20. The substrate 15 comprises a reflection layer 23, and an insulating layer 24 located around the reflection layer 23. The semiconductor light-emitting element 16 is mounted in the reflection layer 23. The metal conductor 17 electrically connects the semiconductor light-emitting element 16 and an external circuit. The metal wire 18 electrically connects each semiconductor light-emitting element 16. A phosphor is mixed into the phosphor sealing part 19, and the phosphor sealing part is provided so as to cover the semiconductor light-emitting element 16 and the reflection layer 23. The phosphor sealing part 19 is set in a triangular shape or a semicircular shape in which a cross-sectional aspect ratio of an outer edge is not less than 0.2 and not more than 0.7. The transparent sealing part 20 is provided on the phosphor sealing part 19, and set in a semicircular shape in which the cross-sectional aspect ratio of the outer edge is not less than 0.2 and not more than 0.7.SELECTED DRAWING: Figure 1

Description

  Embodiments described herein relate generally to a light emitting module including a plurality of semiconductor light emitting elements.

LED (Light Emitting Diode) lighting can reduce carbon dioxide (CO ₂ ), which is one of the causes of global warming by saving power. It is increasing rapidly. As a general light emitting form of LED lighting, an LED chip is electrically connected, and a cover layer in which the phosphor is mixed is provided by covering the LED chip, so that the excitation light and the phosphor from the LED chip are provided. The desired light color is obtained by mixing the emitted light from the.

  In recent years, a chip on board (COB (Chip On Board)) system in which a plurality of LED chips are mounted on a substrate (board) for the purpose of increasing the brightness is becoming popular. Among them, the mainstream is a bank (phosphor liquid damming function part) formed on a substrate on which a large number of LED chips are mounted, which is suitable for light bulbs and spotlights. It is a collective mounting type that has been cast and cured.

  On the other hand, in the case of large-scale lighting such as base lights for facilities, LED chips are mounted on a large substrate at regular intervals due to the cost of bank materials and appearance problems such as the bank that does not emit light interferes with the collective mounting type. There is also a linear mounting type in which a phosphor-mixed resin made of a resin having high thixotropy is directly applied without forming a bank.

  Thus, although it is a COB module developed for the purpose of increasing the brightness, there is a concern that the characteristics may be insufficient with respect to the recent demand for higher efficiency.

JP 2013-98389 A

  The problem to be solved by the present invention is to provide a light emitting module with improved luminous efficiency.

  The light emitting module of the embodiment includes an insulating substrate, a plurality of semiconductor light emitting elements, a metal conductor, a metal wire, a phosphor sealing portion, and a transparent sealing portion. The substrate includes a reflective layer and an insulating layer located around the reflective layer. The semiconductor light emitting element is mounted on the reflective layer. The metal conductor electrically connects the semiconductor light emitting element and the external circuit. The metal wire electrically connects each semiconductor light emitting element. The phosphor sealing portion is provided so as to cover the semiconductor light emitting element and the reflective layer, with the phosphor mixed therein. In addition, the phosphor sealing portion is set in a triangular or semicircular shape having a cross-sectional aspect ratio of the outer edge of 0.2 to 0.7. The transparent sealing portion is provided on the phosphor sealing portion, and is set in a semicircular shape having a cross-sectional aspect ratio of the outer edge of 0.2 or more and 0.7 or less.

  According to the present invention, improvement in luminous efficiency can be expected.

(A) is sectional drawing which shows the light emitting module of 1st Embodiment, (b) is the one part enlarged view of (a). It is a top view which expands and shows typically a part of light emitting module same as the above. It is a perspective view of a light emitting module same as the above. It is sectional drawing which expands and shows a part of light emitting module of 2nd Embodiment.

  The configuration of the first embodiment will be described below with reference to FIGS.

  FIG. 3 shows a light emitting module 10, which is a long one used in a lighting fixture such as a base light for general lighting.

  The light emitting module 10 includes an insulating substrate 15, a plurality of semiconductor light emitting elements 16, a metal conductor 17, a metal wire 18, a fluorescent light, as shown in FIGS. The COB module includes a body sealing part 19 and a transparent sealing part 20.

  The substrate 15 is formed in a long plate shape. For example, a reflective layer 23 on which the semiconductor light emitting element 16 is mounted is formed on the surface of a base material 22 made of a synthetic resin such as an epoxy resin. An insulating layer 24 is formed around the layer 23.

  The reflective layer 23 is, for example, a highly reflective resist layer (highly reflective insulating layer) having a reflectance of 92% or more. In the present embodiment, the reflection layer 23 is set to have a reflectance of 96%, for example. The reflective layer 23 may be formed in multiple layers.

  The insulating layer 24 is a white resist layer having a reflectance of 90% or more, for example. That is, the insulating layer 24 is set to have a lower reflectance than the reflective layer 23. The insulating layer 24 is formed so as to cover the surface of the base material 22 of the substrate 15 excluding the reflective layer 23.

  In this embodiment, the semiconductor light emitting element 16 is, for example, a rectangular parallelepiped bare chip of a light emitting diode (LED) that emits blue light. The semiconductor light emitting element 16 is mounted on the reflective layer 23 of the substrate 15 by die bonding using, for example, a white or silver resin adhesive having a high reflectance. Therefore, the region where the semiconductor light emitting element 16 is disposed is the light emitting region 26 of the light emitting module 10. The light emitting region 26 is, for example, a rectangular region that extends in the longitudinal direction and the width direction of the substrate 15. The semiconductor light emitting elements 16 are arranged along the longitudinal direction of the substrate 15 at a substantially constant narrow pitch with the shortest pitch P being 0.3 mm or less, for example. That is, the semiconductor light emitting element 16 is mounted on the substrate 15 in a line shape. Further, in order to suppress mutual absorption of light emission, these semiconductor light emitting elements 16 are alternately arranged in the longitudinal direction in the arrangement shifted in the width direction (short direction) of the substrate 15 as shown in FIGS. Are arranged in a so-called staggered pattern. While these semiconductor light emitting elements 16 can suppress mutual absorption as they are largely shifted in the width direction of the substrate 15, the width of the substrate 15 (light emitting region 26) is increased. About half of each of them is shifted in the width direction of the substrate 15. In the staggered arrangement of the semiconductor light emitting elements 16, the length overlapping with the adjacent semiconductor light emitting elements 16 is preferably 0.25 to 0.75 times the width dimension L of the semiconductor light emitting elements 16.

  The metal conductor 17 is for electrically supplying the semiconductor light emitting element 16 from the external circuit by electrically connecting the semiconductor light emitting element 16 and an external circuit (not shown). The metal conductor 17 is formed by plating the surface with, for example, gold (Au) or silver (Ag). The metal conductor 17 is provided on the surface of the base material 22, a part thereof is exposed and electrically connected to the metal wire 18, and the other part is covered with the insulating layer 24.

  A metal wire 18 shown in FIGS. 1A and 1B is wire-bonded to each semiconductor light emitting element 16 and electrically connects the adjacent semiconductor light emitting elements 16 and 16. Therefore, the semiconductor light emitting elements 16 and 16 are connected in series by the metal wire 18 between the metal conductors 17. These metal wires 18 are thin wires having a diameter of 20 μm or less, preferably 15 μm, for example, so as not to cause a shadow on the light from the semiconductor light emitting element 16. In addition, among the plurality of semiconductor light emitting elements 16, one metal line 18 connected to the semiconductor light emitting element 16 located at the end of the array is electrically connected to the metal conductor 17.

  The phosphor sealing portion 19 is, for example, a silicone resin having electrical insulation and thermal conductivity, contains a phosphor (not shown) at a predetermined concentration, covers the semiconductor light emitting element 16 and the reflective layer 23, that is, a light emitting region. 26 is covered with a long shape. The phosphor sealing portion 19 is made of, for example, a highly viscous resin having a thixotropy in which a predetermined amount of phosphor is dispersed so as to cover the semiconductor light emitting element 16 and the reflective layer 23 (light emitting region 26). ) And cured. The phosphor is, for example, a yellow phosphor that converts the wavelength of blue light into yellow light. And in this fluorescent substance sealing part 19, the blue light radiated | emitted from the semiconductor light-emitting element 16 and the yellow light by which the wavelength conversion of a part of this blue light was carried out by the fluorescent substance are mixed (color mixing). White light is emitted to the external space as the light emitting module 10 (light emitting region 26).

  Further, the phosphor sealing portion 19 has a shape in which the cross section of the outer edge protrudes most at the center position in the width direction. Specifically, the phosphor sealing portion 19 has a cross-sectional outer edge portion set in a triangular or semicircular shape. The cross-sectional aspect ratio of the phosphor sealing portion 19 is 0.2 or more and 0.7 or less. Here, the cross-sectional aspect ratio is defined as height / width when viewed in a cross-section along the width direction. In the present embodiment, the outer edge of the cross section of the phosphor sealing portion 19 is set to a semicircular shape with a cross-sectional aspect ratio of, for example, 0.4.

  The transparent sealing portion 20 is a lens-shaped member that improves the light extraction efficiency by condensing the light emitted from the phosphor sealing portion 19 and controls the light distribution of the light emitting module 10. The transparent sealing portion 20 is formed of a transparent synthetic resin or the like and is provided on the phosphor sealing portion 19. That is, the transparent sealing portion 20 is formed in a long dome shape (kamaboko shape) covering the surface (outer edge) of the phosphor sealing portion 19. The outer edge of the cross section of the transparent sealing portion 20 is set to a semicircular shape having a cross-sectional aspect ratio of 0.2 or more and 0.7 or less. In the present embodiment, the outer edge of the cross section of the transparent sealing portion 20 is set in a semicircular shape with a cross sectional aspect ratio of, for example, 0.5. Therefore, the transparent sealing portion 20 has a larger cross-sectional aspect ratio at the outer edge than the phosphor sealing portion 19. In the present embodiment, the transparent sealing portion 20 is formed on the surface of the phosphor sealing portion 19 with a substantially constant thickness.For example, a desired light distribution characteristic can be obtained by partially varying the thickness. You can also get it.

  Then, when manufacturing the light emitting module 10, the substrate 15 is manufactured by forming the reflective layer 23, the metal conductor 17, and the insulating layer 24 on the base material 22, respectively. Next, the semiconductor light emitting elements 16 are mounted in a staggered pattern on the reflective layer 23 of the substrate 15, and wire bonding is performed with the metal wires 18. Further, a high-viscosity resin having thixotropy in which a predetermined amount of phosphor is dispersed so as to cover the semiconductor light emitting element 16 and the reflective layer 23 (light emitting region 26) has a cross-sectional aspect ratio of the outer edge of 0.2 to 0.7 The phosphor sealing portion 19 is formed by applying and pre-curing so as to be the following. Thereafter, on the temporarily cured phosphor sealing portion 19, a transparent high-viscosity resin is applied and cured so that the cross-sectional aspect ratio of the outer edge is 0.2 or more and 0.7 or less. A transparent sealing portion 20 is formed so as to integrally cover the phosphor sealing portion 19.

  When the semiconductor light emitting element 16 fed from the external circuit through the metal conductor 17 and the metal wire 18 is turned on, the direct light from the semiconductor light emitting element 16 to the phosphor sealing portion 19 and the reflection layer 23 and the insulating layer of the substrate 15 The reflected light reflected by 24 enters the phosphor sealing portion 19. In this phosphor sealing part 19, the incident light and the light from the phosphor excited by this light are mixed, and the outer peripheral cross-sectional aspect ratio is 0.2 or more and 0.7 or less triangular or semicircular shape The light is emitted while being condensed according to the shape of the phosphor sealing portion 19. Then, the light emitted from the phosphor sealing portion 19 is condensed and distributed by the transparent sealing portion 20 having a semicircular shape with a cross-sectional aspect ratio of the outer edge of 0.2 or more and 0.7 or less, The light emitted from the light emitting module 10 is emitted. As a result, the luminous efficiency can be further improved.

  In particular, since the phosphor sealing portion 19 is formed by curing a high-viscosity resin having thixotropy, there is an enclosure such as a bank for molding the phosphor sealing portion 19 or maintaining its shape. This is unnecessary, and can be reduced in size and weight, and the manufacturing cost can be suppressed.

  By providing the reflective layer 23 having a reflectance of 92% or more at the position where the semiconductor light emitting element 16 is mounted, the substrate 15 can efficiently reflect the light from the semiconductor light emitting element 16 and further improve the light emission efficiency. .

  In addition, the substrate 15 covers the periphery of the reflective layer 23 with the insulating layer 24 having a reflectance of 90% or more, thereby improving the insulating property and suppressing the decrease in the light emission efficiency.

  By setting the diameter of the metal wire 18 to 20 μm or less, shadows due to the metal wire 18 are hardly generated, and the light emission efficiency can be further improved.

  By arranging the semiconductor light emitting elements 16 in a staggered pattern on the reflective layer 23 of the substrate 15, mutual absorption of light emitted from each semiconductor light emitting element 16 is suppressed even in high-density mounting where the shortest pitch P is 0.3 mm or less. In addition, the luminous efficiency can be further improved.

  The light emitting module 10 of the present embodiment can expect an improvement in light emission efficiency of 4%, for example.

  Next, a second embodiment will be described with reference to FIG. In addition, about the structure and effect | action similar to the said 1st Embodiment, the same code | symbol is attached | subjected and the description is abbreviate | omitted.

  In the second embodiment, the substrate 15 of the first embodiment is provided with a reflective layer 23 formed on the surface of a base material 28 such as an insulating ceramic. The semiconductor light emitting element 16 is mounted on the reflective layer 23.

  Therefore, a part of the light from the semiconductor light emitting element 16 is reflected only by the reflective layer 23 having a high reflectance without using a layer such as an insulating layer having a reflectance smaller than that of the reflective layer 23 such as a white resist. Since the light is incident on the phosphor sealing portion 19, the light emission efficiency can be further improved.

  Moreover, heat resistance can be improved by comprising the base material 28 with a ceramic etc. FIG.

  The light emitting module 10 of this embodiment can expect an improvement in light emission efficiency of 8%, for example.

  In each of the above embodiments, the phosphor sealing portion 19 may eliminate the provisional curing step before the transparent sealing portion 20 is cured by adjusting the viscosity of the resin before formation to be harder.

  The transparent sealing portion 20 may be integrated by, for example, covering the phosphor sealing portion 19 with a preformed material such as a transparent resin, etc., and adhering to the surface of the phosphor sealing portion 19 via an adhesive, for example. .

  Although several embodiments of the present invention have been described, these embodiments are presented by way of example and are not intended to limit the scope of the invention. These novel embodiments can be implemented in various other forms, and various omissions, replacements, and changes can be made without departing from the scope of the invention. These embodiments and modifications thereof are included in the scope and gist of the invention, and are included in the invention described in the claims and the equivalents thereof.

10 Light emitting module
15 Board
16 Semiconductor light emitting devices
17 Metal conductor
18 Metal wire
19 Phosphor seal
20 Transparent sealing part
23 Reflective layer
24 Insulation layer

Claims (3)

An insulating substrate comprising a reflective layer and an insulating layer located around the reflective layer;
A plurality of semiconductor light emitting devices mounted on the reflective layer;
A metal conductor that electrically connects the semiconductor light emitting element and an external circuit;
A metal wire for electrically connecting the semiconductor light emitting elements;
A phosphor encapsulating part in which a phosphor is mixed, is provided so as to cover the semiconductor light emitting element and the reflective layer, and has a cross-sectional aspect ratio of an outer edge of 0.2 to 0.7. When;
A transparent sealing portion provided on the phosphor sealing portion and set in a semicircular shape with a cross-sectional aspect ratio of the outer edge of 0.2 to 0.7;
A light emitting module comprising: An insulating substrate with a reflective layer;
A plurality of semiconductor light emitting devices mounted on the reflective layer;
A metal conductor connecting the semiconductor light emitting element and an external circuit;
A metal wire connecting the semiconductor light emitting elements;
A phosphor encapsulating part in which a phosphor is mixed, provided so as to cover the semiconductor light emitting element and the reflective layer, and set in a triangular or semicircular shape having a cross-sectional aspect ratio of 0.2 to 0.7;
A transparent sealing portion provided on the phosphor sealing portion and set in a semicircular shape having a cross-sectional aspect ratio of 0.2 to 0.7;
A light emitting module comprising: The light emitting module according to claim 1, wherein the semiconductor light emitting elements are arranged in a staggered pattern on the reflective layer of the substrate with a shortest pitch of 0.3 mm or less.

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