JP2007317816A - Light-emitting device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a light-emitting device for preventing emission characteristics from deteriorating due to the sagging or crawling of resin. <P>SOLUTION: The light-emitting device has a package 1 having a recess 11 that is open in a rectangular shape on an outer surface, wherein an LED chip 2 is mounted into the recess 11 and a phosphor sheet 3 is stuck to a step part 12 provided at the open edge of the recess 11 so that the phosphor sheet 3 covers the recess 11 via resin. A fitting projection 31 is provided at the step part 12, and a fitting recess 13 is provided at the phosphor sheet 3. The phosphor sheet 3 is stuck so that it is placed on the bottom surface of the step part 12 by fitting the fitting recess 13 to the fitting projection 31 via a sticking resin 5 applied to the bottom surface of the step part 12 in advance. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  Conventionally, as disclosed in Japanese Patent Application Laid-Open No. 2005-244075 (Patent Document 1), a light emitting device in which an LED chip and a phosphor sheet are mounted on a package is known. As shown in FIG. 5, the light emitting device includes an LED chip 92 mounted on the bottom surface of the recess 93 of the package 91, and a step 94 provided on the periphery of the recess 93. A phosphor sheet 95 is fixed to the stepped portion 94 via a fixing resin. Further, the step portion 94 has a large width so that the step portion space 96 remains on the periphery of the step portion 94 in a state where the phosphor sheet 95 is placed.

Therefore, the fixing force of the phosphor sheet 95 can be increased by storing the fixing resin in the step space 96.
JP-A-2005-244075

  On the other hand, the LED chip has recently been increased in size due to higher brightness, and the sealing resin for sealing the LED chip needs to have a relatively low viscosity in order to relieve stress on the larger chip. There is. However, also in the fixing resin, when a resin having the same viscosity as that of the sealing resin is used, the fixing force is not sufficient, so that it is necessary to increase the application amount of the fixing resin.

  However, in the light emitting device according to the above-described conventional example, although a certain amount of excess fixing resin can be released to the stepped space 96, the phosphor sheet 95 comes into contact with the side surface of the stepped portion 94 on one side. The step space 96 is eliminated on one side, and there is no space for the resin to escape. Therefore, particularly when a large amount of resin having a low viscosity is applied to the stepped portion, if the stepped portion space 96 is eliminated, the fixing resin applied to the stepped portion 94 may hang down from the stepped portion 94 to the bottom surface of the recess 93 or the stepped portion. As a result, the light emission characteristic of the light emitting device is deteriorated.

  The present invention has been invented in view of the above-described background art, and an object thereof is to provide a light-emitting device that prevents deterioration of light-emitting characteristics due to dripping or creeping up of a resin.

  In order to solve the above-mentioned problems, the invention according to claim 1 of the present application includes a package having a rectangular recessed portion on the outer surface, an LED chip is mounted in the recessed portion, and a step provided at the opening edge of the recessed portion. In the light emitting device, the phosphor sheet is fixed so as to cover the concave portion through a resin, and a fitting convex portion is provided on one of the stepped portion and the phosphor sheet, and a fitting concave portion is provided on the other. The phosphor sheet is characterized in that the fitting convex portion and the fitting concave portion are fitted to be fixed to the stepped portion.

  Further, in the invention according to claim 2 of the present application, in the light emitting device according to claim 1, the fitting recess is provided in the stepped portion, and the excess of the resin is accumulated in the fitting recess. It is characterized by that.

  In the light emitting device according to the first aspect of the present invention, the phosphor sheet is fitted and fixed to the step portion, so that the step space on the periphery of the step portion is prevented from being lost by approaching the side surface of the step portion on one side. be able to. Therefore, since the excess resin applied to the stepped portion accumulates in the stepped portion space, it hangs down from the stepped portion to the bottom surface of the concave portion, or crawls up from the stepped portion to the outside of the concave portion or the top surface of the phosphor sheet, It is possible to prevent the light emission characteristics of the light emitting device from deteriorating.

  Moreover, the phosphor sheet can be fixed without slipping by being fitted to the stepped portion. Furthermore, since the fitting convex part and the fitting concave part are provided, the adhesion area of the resin in the phosphor sheet and the package is increased, and the fixing force can be increased.

  Further, in the light emitting device according to claim 2, since the fitting recess is provided in the step portion and can store an excessive amount of resin, even when a large amount of resin is applied, the resin may sag. It can prevent crawling up.

  1 and 2 show a light emitting device according to a first embodiment corresponding to claims 1 and 2 of the present application. This light-emitting device includes a package 1 having a rectangular recess 11 on the outer surface, the LED chip 2 is mounted in the recess 11, and resin is applied to a step 12 provided on the opening edge of the recess 11. The phosphor sheet 3 is fixed so as to cover the concave portion 11, the fitting portion 13 is provided in the step portion 12, and the fitting convex portion 31 is provided in the phosphor sheet 3. Is provided.

  Hereinafter, the light-emitting device of this embodiment will be described in more detail. As shown in FIGS. 1 and 2, the package 1 of the light emitting device has a rectangular parallelepiped shape of about 5 to 8 mm square made of ceramic or the like, and has a concave portion 11 opened in a rectangular shape. A step 12 is formed at the periphery of the recess 11, and the center side of the recess 11 opens in a deeper circle from the step 12, and the opening becomes narrower toward the bottom. A fitting recess 13 is provided in the center of the bottom surface of the step portion 12 in a groove shape over the entire circumference of the step portion 12.

  The bottom surface of the recess 11 is a mounting surface 15 provided with chip connection electrodes and the like, and the LED chip 2 is mounted on the mounting surface 15. The LED chip 2 is formed of, for example, a gallium nitride-based semiconductor compound material (GaN, InGaN) that emits blue light, and a plurality of such LED chips 2 may be provided on the mounting surface 15. The mounted LED chip 2 is sealed with a low-viscosity transparent sealing resin 4 such as an epoxy resin or a silicone resin.

  The light emitting device also includes a phosphor sheet 3 formed of a resin mixed with phosphor particles, a glass substrate, or the like. For example, a part of blue light emitted from the LED chip 2 is phosphor sheet. By being converted into yellow light by 3, white light is emitted from the light emitting device. The phosphor sheet 3 has a thickness of about 0.5 mm, but is not particularly limited to this thickness.

  Further, in the vicinity of the periphery of the phosphor sheet 3, a fitting convex portion 31 that is fitted into the fitting concave portion 13 provided in the step portion 12 is provided. Accordingly, the phosphor sheet 3 is placed on the bottom surface of the step portion 12 by fitting the fitting concave portion 13 and the fitting convex portion 31 through the fixing resin 5 applied to the bottom surface of the step portion 12 in advance. It is fixed. Further, in this state, the step portion 12 is dimensioned such that a step portion space 16 that is not blocked by the phosphor sheet 3 remains at the periphery of the step portion 12. Furthermore, the fitting recess 13 is formed deep so that the lower space 17 remains in a state of being fitted with the fitting protrusion 31. The fixing resin 5 is a low-viscosity resin made of the same material as the sealing resin 4.

  Next, the manufacturing process of this light emitting device will be described. First, the LED chip 2 is mounted on the mounting surface 15 by being connected to a chip connection electrode or the like provided on the mounting surface 15. Then, the mounted LED chip 2 is sealed with the sealing resin 4, and the fixing resin 5 is applied to the bottom surface of the stepped portion 12. Since the fixing resin 5 is a low-viscosity resin made of the same material as the sealing resin 4, it is applied in a large amount to supplement the fixing force. Finally, the phosphor sheet 3 is placed on the bottom surface of the stepped portion 12 by fitting the fitting concave portion 13 and the fitting convex portion 31 through the fixing resin 5, and the fixing resin 5 and the sealing resin 4 are heated. Harden. Here, when the phosphor sheet 3 is placed, the excess of the fixing resin 5 is pushed out to the phosphor sheet 3 and escapes to the lower space 17 and the step space 16 of the fitting recess 13. Yes.

  Therefore, in the light emitting device of this embodiment, the phosphor sheet 3 is fitted and fixed to the step portion 12, so that the step portion space 16 on the periphery of the step portion 12 can be obtained by approaching the side surface of the step portion 12 on one side. Can be eliminated. Therefore, since the excess resin applied to the step portion 12 is accumulated in the step portion space 16, it droops from the step portion 12 to the bottom surface of the recess 11, or from the step portion 12 to the outside of the recess 11 or the upper surface of the phosphor sheet 3. It is possible to prevent the light emission characteristics of the light emitting device from deteriorating.

  Further, the phosphor sheet 3 can be fixed without being displaced by being fitted to the stepped portion 12. Furthermore, since the fitting convex part 31 and the fitting concave part 13 are provided, the adhesion area of the fixing resin 5 in the phosphor sheet 3 and the package 11 is increased, and the fixing force can be increased.

  Further, since the fitting recess 13 is provided in the step portion 12 and can store an excessive amount of resin, even when a large amount of resin is applied, the resin can be prevented from dripping or creeping up. .

  Moreover, since the sealing resin 4 uses a low-viscosity resin, the influence of stress on the LED chip 2 can be suppressed. Therefore, even when a relatively large LED chip 2 is sealed, the LED chip 2 can be effectively sealed without causing a problem that the LED chip 2 is peeled off. Furthermore, since the fixing resin 5 is made of the same material as that of the sealing resin 4, it can be applied in the same process as the sealing resin 4, and the production process can be shortened.

  FIG. 3 shows a light emitting device according to a second embodiment corresponding to claim 1 of the present application. Here, only matters different from those in the first embodiment will be described, and other matters (configuration, operational effects, and the like) are the same as those in the first embodiment, and the description thereof will be omitted. Unlike the first embodiment, this light emitting device is provided with a fitting recess 32 in the phosphor sheet 3 and a fitting protrusion 14 on the bottom surface of the stepped portion 12.

  The fitting recess 32 is provided so as to be cut out in a rectangular shape on the bottom surface of the phosphor sheet 3, leaving only the peripheral portion. Further, the fitting convex portion 14 is provided in a triangular shape over the entire circumference of the bottom surface of the step portion 12. The phosphor sheet 3 is placed and fixed on the bottom surface of the stepped portion 12 by fitting the fitting convex portion 14 into the fitting concave portion 32. Accordingly, the step space 16 is not blocked by the phosphor sheet 3, and the excess fixing resin 5 can be released to the step space 16.

  FIG. 4 shows a light emitting device according to a third embodiment corresponding to claims 1 and 2 of the present application. Here, only matters different from those in the first embodiment will be described, and other matters (configuration, operational effects, and the like) are the same as those in the first embodiment, and the description thereof will be omitted. In this light emitting device, in the light emitting device according to the first embodiment, a condensing lens 6 is placed on and fixed to the LED chip 2 instead of the sealing resin 4. Note that this structure may also be used in the second embodiment.

The top view which shows the light-emitting device which is 1st embodiment of this invention. Sectional drawing which shows the light-emitting device. Sectional drawing which shows the light-emitting device which is 2nd embodiment of this invention. Sectional drawing which shows the light-emitting device which is 3rd embodiment of this invention. Sectional drawing which shows the light-emitting device which is a prior art example.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Package ・ Recessed part ・ Step part ・ Fitting concave part ・ Fitting convex part 2 LED chip 3 Phosphor sheet ・ Fitting convex part ・ Fitting concave part

Claims (2)

  Provided with a package having a rectangular opening on the outer surface, an LED chip is mounted in the depression, and a phosphor sheet covers the depression on the step provided at the opening edge of the depression through a resin. A light-emitting device formed by being fixed, wherein either one of the stepped portion and the phosphor sheet is provided with a fitting convex portion, and the other is provided with a fitting concave portion, and the phosphor sheet includes a fitting convex portion and a fitting concave portion. A light emitting device characterized by being fitted to and fixed to the stepped portion.   The light emitting device according to claim 1, wherein the fitting recess is provided in a stepped portion, and the excess of the resin is accumulated in the fitting recess.

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