JP2019140305A - Light-emitting device - Google Patents

Abstract

To provide a light-emitting device in which a step of brilliance is less between regions of different brilliance, and visibility is high.SOLUTION: A light-emitting device has a mounting board 11, and multiple light-emitting structures 10A, 10B juxtaposed on the mounting board and arranged in a first arrangement direction and a second arrangement direction perpendicular to the first arrangement direction, where each of the multiple light-emitting structures includes a semiconductor light-emitting element 12, and a wavelength conversion member 17 formed on a top face of the semiconductor light-emitting element. In at least one of the light-emitting structures located at both ends in the first arrangement direction, lateral faces of the semiconductor light-emitting element and the wavelength conversion member facing the light-emitting structure adjoining in the first arrangement direction are coated with a coating member 19, the lateral face of the semiconductor light-emitting element at an end side in the first arrangement direction is coated with the coating member, and the lateral face of the wavelength conversion member is exposed.SELECTED DRAWING: Figure 1B

Description

  The present invention relates to a light emitting device using a plurality of light emitting elements such as light emitting diodes (LEDs).

  A light emitting device in which light emitted from a semiconductor light emitting element has a luminance gradient is known. For example, Patent Document 1 includes a phosphor layer containing phosphor particles and a scattering layer containing scattering particles, and the thickness gradient of the phosphor layer and the thickness gradient of the scattering layer have an inverse relationship. A light-emitting device for an automobile headlamp is disclosed.

  There is also known a light emitting device in which a plurality of semiconductor light emitting elements are fixed on a mounting substrate. For example, light distribution control may be performed by controlling the regions irradiated by each of the plurality of semiconductor light emitting elements to have different luminances.

JP 2014-72309 A

  When a light-emitting device in which a plurality of semiconductor light-emitting elements are fixed on a mounting board is used for an automotive lamp, a luminance step is increased at the boundary between a high-luminance region and a low-luminance region, thereby reducing visibility. One of the issues is that there was a case.

  The present invention has been made in view of the above points, and an object of the present invention is to provide a light-emitting device that has a small difference in luminance between regions having different luminance and high visibility.

  The light-emitting device of the present invention includes a mounting substrate and a plurality of light-emitting structures that are juxtaposed on the mounting substrate and arranged in a first arrangement direction and a second arrangement direction that is perpendicular to the first arrangement direction. Each of the plurality of light emitting structures includes a semiconductor light emitting element and a wavelength conversion member formed on an upper surface of the semiconductor light emitting element, and is located at both ends in the first arrangement direction. At least one light emitting structure among the light emitting structures is coated with a covering member on a side surface of the semiconductor light emitting element and the wavelength conversion member facing the adjacent light emitting structure in the first arrangement direction. The side surface of the semiconductor light emitting element on the end side in the arrangement direction is covered with the covering member, and the side surface of the wavelength converting member is exposed.

  The light-emitting device of the present invention includes a mounting substrate and a light-emitting structure disposed on the mounting substrate, and the light-emitting structure is formed on the semiconductor light-emitting element and the top surface of the semiconductor light-emitting element. A wavelength conversion member, wherein the semiconductor light emitting element and the wavelength conversion member have four side surfaces, the four side surfaces of the semiconductor light emitting element are covered with a covering member, and the four side surfaces of the wavelength conversion member At least one of these is exposed, and the other side surface is covered with the covering member.

1 is a top view of a light emitting device according to Example 1. FIG. 1 is a cross-sectional view of a light emitting device according to Example 1. FIG. 1 is an enlarged cross-sectional view of a light emitting device according to Example 1. FIG. 3 is a cross-sectional view of a light emitting structure according to Example 1. FIG. FIG. 3 is a diagram schematically illustrating a luminance distribution of the light emitting device according to Example 1. 6 is a diagram schematically showing a luminance distribution of a light emitting device according to Example 2. FIG. FIG. 6 is a diagram schematically illustrating a luminance distribution of a light emitting device according to Example 3. 6 is a cross-sectional view of a light emitting structure according to Example 4. FIG. 10 is a graph showing luminance at an end of a light emitting structure according to Example 4. It is a figure which shows typically the luminance distribution of the light-emitting device which concerns on Example 4. FIG. FIG. 10 is a cross-sectional view of a modification of the light emitting structure according to Example 4. It is sectional drawing of the modification of the light emitting structure which concerns on an Example.

  Hereinafter, preferred embodiments of the present invention will be described in detail. In the following description and the accompanying drawings, substantially the same or equivalent parts are denoted by the same reference numerals.

  The light-emitting device of Example 1 will be described with reference to FIGS. 1A and 1B. FIG. 1A is a top view showing the light emitting device 100 of Example 1. FIG. As shown in FIG. 1A, the light emitting device 100 has a plurality of light emitting structures 10 juxtaposed on a mounting substrate 11. The plurality of light emitting structures 10 are arranged in the X direction (first arrangement direction) and the Y direction (second arrangement direction) which is a direction perpendicular to the X direction.

  FIG. 1A shows an example in which three light emitting structures 10 are arranged in the X direction and five or more light emitting structures 10 are arranged in the Y direction. The light emitting structure 10 includes a light emitting structure 10A and a light emitting structure 10B that are partially different in structure. As shown in FIG. 1A, the light emitting structure 10 has, for example, a rectangular parallelepiped shape or a cubic shape, and has a rectangular shape when viewed from above.

  FIG. 1B is a cross-sectional view showing a cross-section along AA in FIG. 1A. As shown in FIG. 1B, the light emitting structure 10A is arranged at the center, and the light emitting structures 10B are arranged on both sides of the light emitting structure 10A, that is, at both ends in the X direction. First, the light emitting structure 10A will be described.

  The light emitting structure 10 </ b> A includes a semiconductor light emitting element 12 disposed on the mounting substrate 11. The semiconductor light emitting element 12 includes a semiconductor structure layer 13, a p-electrode 14 </ b> A, an n-electrode 14 </ b> B, and a translucent substrate 15. The semiconductor structure layer 13 includes a plurality of semiconductor layers including a light emitting layer and emits light.

  FIG. 1C is an enlarged cross-sectional view of the light emitting structure 10A of FIG. 1B. As shown in FIG. 1C, the semiconductor structure layer 13 is configured by stacking a p-type semiconductor layer 13A, a light emitting layer 13B, and an n-type semiconductor layer 13C in this order. The semiconductor structure layer 13 is disposed so that the light emitting layer 13 </ b> B is parallel to the mounting substrate 11.

  The p-type semiconductor layer 13A of the semiconductor structure layer 13 is electrically connected to the p-electrode 14A. The n-type semiconductor layer 13C of the semiconductor structure layer 13 is electrically connected to the n-electrode 14B. For example, the n-electrode 14B is connected to the n-type semiconductor layer 13C through the p-type semiconductor layer 13A and the light-emitting layer 13B through a through-hole having a sidewall SW made of an insulator.

  The p-electrode 14A is electrically connected to a p-side wiring (not shown) on the mounting substrate side. The n-electrode 14B is electrically connected to an n-side wiring (not shown) on the mounting substrate side. For example, a plurality of p-side wirings on the mounting substrate side may be provided, and each of them may be electrically isolated.

  The translucent substrate 15 is provided on the light emitting surface 13 </ b> S that is the upper surface of the semiconductor structure layer 13. The translucent substrate 15 is a substrate such as a sapphire substrate, and transmits light from the semiconductor structure layer 13.

  The wavelength conversion member 17 is provided on the translucent substrate 15. The wavelength conversion member 17 is a member including a wavelength conversion material such as phosphor particles. For example, the wavelength conversion member 17 may be a resin containing a phosphor such as a YAG: Ce phosphor. Alternatively, the wavelength conversion member 17 may include a glass support and a phosphor thin film. Therefore, the wavelength conversion member 17 converts the wavelength of the light emitted from the semiconductor structure layer 13 and transmitted through the translucent substrate 15.

  The covering member 19 is provided so as to cover the side surfaces of the semiconductor structure layer 13, the translucent substrate 15, and the wavelength conversion member 17. That is, the covering member 19 covers the side surfaces of the semiconductor light emitting element 12 and the wavelength conversion member 17. This covering structure is referred to as a first covering structure. That is, the side surface facing the light emitting structure 10B adjacent in the X direction of the light emitting structure 10A has the first covering structure.

  The covering member 19 is a member including a material that reflects light, for example. For example, the covering member 19 is formed of a so-called white resin material in which a light scattering material is dispersed in a resin material such as a silicone resin.

  Referring to FIG. 1C, the light from the semiconductor structure layer 13 is reflected by the covering member 19 and is emitted from above the light emitting structure 10 </ b> A, that is, from the upper surface 17 </ b> S of the wavelength conversion member 17. The covering member 19 prevents a phenomenon called crosstalk between adjacent light emitting structures.

As the resin used for the covering member 19, for example, an epoxy resin or a polyamide-based resin can be used. As the light scattering material, white pigment particles such as TiO ₂ may be used.

  Next, the light emitting structure 10B will be described. As shown in FIG. 1B, the light emitting structure 10B includes a semiconductor light emitting element 12 in the same manner as the light emitting structure 10A. The light emitting structure 10 </ b> B includes a wavelength conversion member 17 and a covering member 19.

  As shown in FIG. 1B, the side surfaces of the semiconductor light emitting element 12 and the wavelength conversion member 17 facing the light emitting structure 10A adjacent to each other in the X direction (first arrangement direction) of the light emitting structure 10B are covered with a covering member 19. ing. On the other hand, the side surface of the semiconductor light emitting element 12 on the end side in the X direction is covered with the covering member 19, but the side surface of the wavelength conversion member 17 on the end side in the X direction is not covered with the covering member 19 ( 17W in the figure). That is, the side surface of the semiconductor light emitting element 12 is covered with the covering member, and the side surface of the wavelength conversion member 17 is exposed. This covering structure is referred to as a second covering structure.

  In this embodiment, the light emitting structure 10B is covered with the covering member 19 on the side surfaces of the semiconductor light emitting element 12 and the wavelength conversion member 17 facing the light emitting structure 10B adjacent in the Y direction (second arrangement direction). It has been broken. Further, in this embodiment, an example in which the light emitting structure 10B has a rectangular parallelepiped shape or a cubic shape is shown. Further, the semiconductor light emitting element 12 and the wavelength conversion member 17 have a rectangular parallelepiped shape or a cubic shape, and have four side surfaces. That is, while the four side surfaces of the semiconductor light emitting element 12 are covered with the covering member 19, at least one of the side surfaces of the wavelength conversion member 17 is exposed and the other side surface is covered with the covering member 19. ing.

  In this embodiment, an example in which the light emitting structure 10 has a rectangular parallelepiped shape or a cubic shape will be described. However, the present invention is not limited to this. For example, the light emitting structure 10 may have another shape such as a shape partially including a curved surface. .

  FIG. 2 is a cross-sectional view showing a cross section in the X direction of the light emitting structure 10B as in FIG. 1B. The arrows in FIG. 2 schematically show the traveling direction of the light emitted from the semiconductor structure layer 13. In FIG. 2, the path of light reflected by the covering member 19 is indicated by a, and the path of light not reflected by the covering member 19 is indicated by b.

  At the end portion having the first covering structure in the X direction (first arrangement direction) of the light emitting structure 10 </ b> B, the light emitted from the semiconductor structure layer 13 is reflected by the covering member 19, and the upper surface of the wavelength conversion member 17. It is emitted from 17S (a in the figure).

  At the end portion having the second covering structure in the X direction of the light emitting structure 10B, the light (a in the figure) emitted from the semiconductor structure layer 13 and reflected by the covering member 19 is applied to the upper surface 17S of the wavelength conversion member 17. It is emitted from. On the other hand, the light (b in the figure) that is guided in the wavelength conversion member 17 and travels toward the exposed side surface 17W of the wavelength conversion member 17 is emitted from the exposed side surface 17W of the wavelength conversion member 17. The

  With reference to FIG. 3, the distribution of irradiation luminance by the light emitting device 100 will be described. (A) in FIG. 3 shows the upper surface of the light emitting structures 10 arranged in the X direction. (B) in FIG. 3 shows a cross section along AA in (a). In FIG. 3, (c) schematically shows the distribution of illumination luminance by the light emitting device 100 along AA in (a). The vertical axis of (c) indicates the X direction, and the horizontal axis indicates the brightness.

  The luminance in (c) in FIG. 3 corresponds to the position in the X direction on the array composed of the light emitting structures 10 arranged in the X direction of the light emitting device 100. B1 in (c) indicates the boundary between the region from one end of the array to the other end and the region outside the region.

  RA shown in (c) of FIG. 3 indicates a luminance region (hereinafter also simply referred to as a region RA) corresponding to a region from the end to the end of the light emitting structure 10A in the X direction. RB in (c) indicates a luminance region outside the luminance region RA (hereinafter also simply referred to as a region RB) among luminance regions corresponding to the region from one boundary B1 to the other boundary B1 in the X direction. Yes. B2 in (c) indicates the boundary between the region RA and the region RB.

  A broken line L1 shown in (c) of FIG. 3 indicates that the light emitting device 100 has a light emitting structure 10A instead of the light emitting structure 10B shown in (a) and (b) of FIG. This represents a luminance distribution (when three structures 10A are arranged) (also referred to as luminance L1). A solid line L2 shown in FIG. 3C represents a luminance distribution by the light emitting structure 10A and the light emitting structure 10B shown in FIGS. 3A and 3B (also referred to as luminance L2).

  The luminance L1 changes sharply at the boundary B1. On the other hand, the luminance L2 changes gently in the vicinity of the boundary B1. As described above, the light emitted from the semiconductor structure layer 13 of the light emitting structure 10B is also emitted from the side surface 17W of the wavelength conversion member 17. For this reason, the luminance L2 changes gently at the boundary B1.

  The luminances L1 and L2 of the three light emitting structures 10 arranged in the X direction are different from each other in the light emitting structures 10B located at both ends in the X direction and the light emitting structures 10A located in the center. An example of lighting differently is shown. As shown in FIG. 3C, the luminances L1 and L2 are higher in the region RA than in the region RB.

  As described above, when light is emitted from the light emitting device 100, the light distribution can be controlled so that the luminance at the center in the X direction is high and the luminance at both ends is low. And by the 2nd coating structure of the light emission structure 10B, the area | region from one edge part of the array which consists of the light emission structure 10 arranged in the X direction of the light-emitting device 100 to the other edge part, and the outer side of the said area | region The change in luminance at the boundary B1 with the region can be moderated. Accordingly, a luminance step between the irradiation region that is the region irradiated by the light emitting device 100 and the outer region can be reduced.

  As described above, according to the light emitting device 100 of the present embodiment, there is little difference in luminance between the irradiation region that is the region irradiated by the light emitting device 100 and the outer region, and the visibility is high. A light-emitting device can be provided.

  With reference to FIG. 4, a light emitting device 200 of Example 2 will be described. 4A shows the top surface of the light emitting structure 10 that is a part of the light emitting device 200 and is arranged in the X direction. The light emitting device 200 includes a plurality of light emitting structures 10 juxtaposed on the mounting substrate 11 and arranged in the X direction and the Y direction, as in the case of the light emitting device 100 of the first embodiment.

  FIG. 4A shows an example in which three light emitting structures 10 are arranged in the X direction. As shown in FIG. 4A, the light emitting structure 10 includes a light emitting structure 10B and a light emitting structure 10C. The light emitting device 200 is different from the light emitting device 100 in that it includes a light emitting structure 10C instead of the light emitting structure 10A, and the other points have the same configuration. As shown in FIG. 4A, the light emitting structure 10C is arranged at the center in the X direction, and the light emitting structures 10B are arranged at both ends in the X direction.

  In FIG. 4, (b) shows a cross section along AA of (a). The light emitting structure 10B is configured similarly to the case of the light emitting device 100 (see FIG. 1B). In the light emitting structure 10C, the side surface of the semiconductor light emitting element 12 facing the light emitting structure 10B adjacent in the X direction is covered with the covering member 19. On the other hand, the side surface of the wavelength conversion member 17 facing the light emitting structure 10B adjacent in the X direction is exposed without being covered by the covering member 19 (17W in the figure).

  That is, both side surfaces of the semiconductor light emitting element 12 facing the light emitting structure 10B adjacent to each other in the X direction (first arrangement direction) of the light emitting structure 10C are covered with the covering member 19, and both side surfaces of the wavelength conversion member 17 are covered. Exposed. In other words, the light emitting structure 10C has the second covering structure at any end in the X direction.

  In FIG. 4, (c) schematically shows the distribution of illumination luminance by the light emitting device 200 along AA in (a). The vertical axis of (c) indicates the X direction, and the horizontal axis indicates the brightness. 4C shows the irradiation luminance of the light emitting structure 10C located in the center of the three light emitting structures 10 arranged in the X direction, rather than the light emitting structures 10B located at both ends in the X direction. It shows an example in which lighting is performed so as to increase.

  The luminance in (c) of FIG. 4 corresponds to the position in the X direction on the array composed of the light emitting structures 10 arranged in the X direction of the light emitting device 200. B1 in (c) indicates the boundary between the region from one end of the array to the other end and the region outside the region.

  RC shown in FIG. 4C indicates a luminance region (hereinafter, also simply referred to as a region RC) corresponding to a region from the end portion to the end portion of the light emitting structure 10C in the X direction. RB in (c) indicates a luminance region outside the luminance region RC among luminance regions corresponding to a region from one boundary B1 to the other boundary B1 in the X direction. B2 in (c) indicates the boundary between the region RC and the region RB. That is, the boundary B2 is a boundary between the high luminance region RC irradiated by the light emitting structure 10C and the low luminance region RB irradiated by the light emitting structure 10B.

  A broken line L1 shown in (c) of FIG. 4 includes a light emitting structure 10A in place of the light emitting structure 10B and the light emitting structure 10C shown in (a) and (b) of FIG. This represents the luminance distribution in the case (that is, when three light emitting structures 10A are arranged) (luminance L1). A solid line L3 shown in (c) of FIG. 4 represents the luminance distribution by the light emitting structure 10B and the light emitting structure 10C shown in (a) and (b) of FIG. 4 (also referred to as luminance L3). At the boundary B1, the luminance L1 changes steeply and the luminance L3 changes gently.

  Also at the boundary B2, the luminance L1 changes steeply and the luminance L3 changes gently. As described above, the boundary B2 corresponds to the end of the light emitting structure 10C in the X direction. Further, the light emitting structure 10C has the second covering structure at both ends in the X direction.

  Therefore, at both ends, the light emitted from the semiconductor structure layer 13 is also emitted from the side surface 17W of the wavelength conversion member 17. As a result, the change in luminance is moderate from the high luminance region RC irradiated by the light emitting structure 10C to the low luminance region RB irradiated by the light emitting structure 10B.

  That is, the luminance step between the high luminance region and the low luminance region is reduced in the region irradiated by the light emitting device 200. As described above, when light is emitted from the light emitting device 200, the light distribution can be controlled such that the luminance in the center in the X direction is high and the luminance gradually decreases toward both ends.

  As described above, according to the light emitting device 200 of the present embodiment, even when each of the light emitting structures 10 is arranged with different luminances, it is between the high luminance region and the low luminance region. Accordingly, a light-emitting device with high visibility can be provided.

  With reference to FIG. 5, a light-emitting device 300 of Example 3 will be described. (A) in FIG. 5 shows an upper surface of the light emitting structure 10 which is a part of the light emitting device 300 and is arranged in the X direction. The light emitting device 300 includes a plurality of light emitting structures 10 juxtaposed on the mounting substrate 11 and arranged in the X direction and the Y direction.

  FIG. 5A shows an example in which six light emitting structures 10 are arranged in the X direction. The light emitting device 300 is different from the light emitting device 200 of the second embodiment in the number of the light emitting structures 10 arranged in the X direction, and has the same configuration with respect to other points. As shown in FIG. 5A, the light emitting device 300 includes a light emitting structure 10 </ b> B and a light emitting structure 10 </ b> C as the light emitting structure 10.

  As shown in FIG. 5A, three light emitting structures 10B, one light emitting structure 10C, and two light emitting structures 10B are arranged in this order along the X direction. (B) in FIG. 5 shows a cross section along AA in (a). The light emitting structure 10B and the light emitting structure 10C are configured in the same manner as the light emitting device 200 of the second embodiment.

  As shown in FIG. 5B, the light emitting structure 10B is disposed between one light emitting structure 10B of the light emitting structures 10B disposed at both ends in the X direction and the light emitting structure 10C. ing. Therefore, in the light emitting structure 10B disposed between the two sides of the semiconductor light emitting element 12 facing the light emitting structure 10 adjacent in the X direction, the covering member 19 covers the light emitting structure 10B, and at least one of the wavelength conversion members 17 is covered. Side 17W is exposed. In the light emitting structure 10B arranged between the two, the side surface 17W of the wavelength conversion member 17 on the same side as the one light emitting structure 10B is exposed.

  In other words, the light emitting structure 10B disposed between the two has a second covering structure on the same side in the X direction as the one light emitting structure 10B. Therefore, in any two light emitting structures 10 adjacent in the X direction, one of the side surfaces 17W of the wavelength conversion member 17 facing each other is exposed.

  (C) in FIG. 5 is a graph schematically showing the distribution of irradiation luminance by the light emitting device 300 along AA in (a). The vertical axis of (c) indicates the X direction, and the horizontal axis indicates the brightness. FIG. 5C shows an example in which six light emitting structures 10 arranged in the X direction are lit so that the irradiation luminance of the light emitting structure 10C is higher than the irradiation luminance of the light emitting structure 10B. Shows about.

  In addition, each of the light emitting structures 10B is lit so that the luminance is lower as it is closer to both ends in the X direction. P shown in FIG. 5C indicates a peak luminance position P that is a position where the light emitting structure 10 having the highest irradiation luminance is disposed.

  The luminance in (c) of FIG. 5 corresponds to the position in the X direction on the array composed of the light emitting structures 10 arranged in the X direction of the light emitting device 300. B1 in (c) indicates a boundary B1 that is a boundary between a region from one end of the array to the other end and a region outside the region. Further, in FIG. 5C, as in the case of FIG. 4C, the region RC, the region RB, and the boundary B2 are shown.

  A broken line L4 shown in FIG. 5C has the light emitting device 300 having a light emitting structure 10A in place of the light emitting structure 10B and the light emitting structure 10C shown in FIGS. 5A and 5B. This represents the luminance distribution in the case (that is, when six light emitting structures 10A are arranged) (luminance L4). A solid line L5 shown in (c) of FIG. 5 represents a luminance distribution by the light emitting structure 10B and the light emitting structure 10C shown in (a) and (b) of FIG. 5 (luminance L5).

  As shown in FIG. 5C, the luminance L4 changes steeply along the X direction at the boundary B1 and the boundary B2. Also, the luminance L4 changes sharply in the luminance region corresponding to the space between the light emitting structure 10B and the adjacent light emitting structure 10B.

  On the other hand, the luminance L5 gradually increases from the peak luminance position P to both ends of the light emitting device 300 along the X direction even in the luminance region corresponding to each of the boundary B1, the boundary B2, and the light emitting structure 10B. It has changed and is gradually getting lower. Therefore, the luminance L5 is a profile in which the luminance level difference is relaxed compared to the luminance L4.

  In this way, the light emitting structure 10C is arranged at the peak luminance position P, and the light emitting structure 10B in which the side surfaces of the wavelength conversion member 17 on the end side are exposed is arranged at the positions of both ends in the X direction. Furthermore, the side surface of the wavelength conversion member 17 on the same side as the light emitting structure 10B at the end is exposed at a position between the light emitting structure 10C and the light emitting structure 10B disposed at the end in the X direction. By arranging the light emitting structure 10B, the light distribution can be controlled so that the luminance gradually decreases from the peak luminance position P to the end in the X direction.

  As described above, according to the light emitting device 300 of the present embodiment, even when each of the four or more light emitting structures 10 is arranged with different luminances, gradually from the peak luminance position to both ends. A gently varying luminance profile is obtained. Therefore, there can be provided a light-emitting device that has few luminance steps between a high-luminance region and a low-luminance region and has excellent visibility.

  A light-emitting device 400 of Example 4 will be described with reference to FIGS. 6A, 6B, and 7. The light emitting device 400 includes a plurality of light emitting structures 10 that are juxtaposed on the mounting substrate 11 and arranged in the X direction and the Y direction that is perpendicular to the X direction, as in the first to third embodiments. ing. The light emitting structure 10 includes a light emitting structure 10D.

  FIG. 6A is a cross-sectional view showing a cross section of the light emitting structure 10D along the X direction. As shown in FIG. 6A, in the light emitting structure 10D, one side surface of the wavelength conversion member 17 is exposed as in the light emitting structure 10B, but the exposed side surface 17W has a rounded convex shape. Have a curved shape (round shape). The light emitting structure 10D is configured in the same manner as the light emitting structure 10B except that the shape of the exposed side surface 17W of the wavelength conversion member 17 is different.

  FIG. 6B is a graph showing the luminance for each distance along the X direction from the end of the wavelength conversion member 17 for the light emitting structure 10A, the light emitting structure 10B, and the light emitting structure 10D. About the light emitting structure 10B and the light emitting structure 10D, it has shown about the edge part of the side which has the side surface 17W which the wavelength conversion member 17 has exposed.

  The horizontal axis of the graph in FIG. 6B indicates the distance along the X direction from the end of the wavelength conversion member 17, and the vertical axis indicates the luminance. The luminance is shown as a ratio when the luminance at a position where the distance from the end is 300 μm is 100%.

  As described above, in the light emitting structure 10A, the side surfaces of the semiconductor light emitting element 12 and the wavelength conversion member 17 are covered with the covering member 19 at the end portion in the X direction, and the light emitted from the semiconductor structure layer 13 is covered. The light is reflected by the member 19 and emitted from the upper surface 17S of the wavelength conversion member 17.

  On the other hand, the light emitting structure 10 </ b> B has a side surface 17 </ b> W where the wavelength conversion member 17 is exposed at the end portion in the X direction, and the light emitted from the semiconductor structure layer 13 is the end portion 17 </ b> W of the wavelength conversion member 17. It is emitted from.

  In the light emitting structure 10D, the exposed side surface 17W of the wavelength conversion member 17 has a round shape. The light emitted from the semiconductor structure layer 13 is emitted from the round-shaped exposed side surface 17 </ b> W of the wavelength conversion member 17.

  As shown in FIG. 6B, any of the light emitting structures 10 has a low luminance of around 20% at the end of the wavelength conversion member 17 (distance = 0). In the light emitting structure 10A, the luminance sharply increases to reach 100% when the distance from the end of the wavelength conversion member 17 is several tens of μm.

  On the other hand, in the light emitting structure 10B, the brightness gradually increases from 0 to 150 to 200 μm from the end of the wavelength conversion member 17 and reaches 100%. Furthermore, the luminance of the light emitting structure 10D gradually increases from the distance 0 to 150 to 200 μm and reaches 100% as compared with the case of the light emitting structure 10B.

  With reference to FIG. 7, the luminance distribution of the light-emitting device 400 of Example 4 will be described. (A) in FIG. 7 shows the upper surface of the light emitting structure 10 that is a part of the light emitting device 400 and is arranged in the X direction. As shown in FIG. 7A, three light emitting structures 10 are arranged in the X direction. The light emitting structure 10 includes a light emitting structure 10D and a light emitting structure 10E. As shown to (a) in FIG. 7, the light emission structure 10E is arrange | positioned in the center of a X direction, and light emission structure 10D is arrange | positioned in the position of the both ends of a X direction.

  FIG. 7B shows a cross section taken along line AA in FIG. Similarly to the light emitting structure 10C, the light emitting structure 10E has both side surfaces of the wavelength conversion member 17 exposed, but the exposed side surface has a rounded convex curved shape (round shape). Have. The light emitting structure 10E is configured in the same manner as the light emitting structure 10C except that the shape of the exposed side surface 17W of the wavelength conversion member 17 is different.

  (C) in FIG. 7 schematically shows the distribution of irradiation luminance by the light emitting device 400 along AA in (a). The vertical axis of (c) indicates the X direction, and the horizontal axis indicates the brightness. Further, FIG. 7C shows that, for the three light emitting structures 10 arranged in the X direction, the irradiation luminance of the light emitting structure 10E located at the center is higher than that of the light emitting structures 10D located at both ends in the X direction. An example of lighting up so as to be higher is shown.

  The luminance distribution in (c) of FIG. 7 corresponds to the position in the X direction on the array composed of the light emitting structures 10 arranged in the X direction of the light emitting device 400. B1 in (c) indicates the boundary between the region from one end of the array to the other end and the region outside the region.

  RE shown in (c) of FIG. 7 indicates a luminance region (hereinafter also simply referred to as region RE) corresponding to a region from the end portion to the end portion of the light emitting structure 10E in the X direction. RD in (c) indicates a luminance region outside the luminance region RE (hereinafter also simply referred to as a region RD) among luminances corresponding to a region from one boundary B1 to the other boundary B1 in the X direction. Yes. B2 in the figure indicates the boundary between the region RD and the region RE, that is, the boundary between the region RE having a high luminance irradiated by the light emitting structure 10E and the region RD having a low luminance irradiated by the light emitting structure 10D. Show.

  7C, the light emitting device 400 includes a light emitting structure 10A in place of the light emitting structure 10D and the light emitting structure 10E illustrated in FIGS. 7A and 7B. This represents the luminance distribution in the case (that is, when three light emitting structures 10A are arranged) (luminance L1). A solid line L6 illustrated in (c) of FIG. 7 represents a luminance distribution by the light emitting structure 10D and the light emitting structure 10E illustrated in (a) and (b) of FIG. 7 (luminance L6). In FIG. 7C, the brightness L1 changes steeply at the boundary B1 and the boundary B2. On the other hand, the luminance L6 changes gently.

  As described above, when the light emitting structure 10 has the exposed side surface 17W of the wavelength conversion member 17, the light emitted from the semiconductor structure layer 13 is emitted from the exposed side surface 17W. In addition, when the exposed side surface 17W of the wavelength conversion member 17 has a round shape, light emitted from the semiconductor structure layer 13 is emitted from the side surface 17W having the round shape and has a moderate luminance profile. (See FIG. 6B).

  Thereby, the change in the luminance L6 is greatly relaxed from the high luminance region RE irradiated by the light emitting structure 10E to the low luminance region RD irradiated by the light emitting structure 10D.

  In this way, when light is emitted from the light emitting device 400, the light distribution can be controlled so that the luminance in the center in the X direction is high and the luminance gradually decreases toward both ends. Changes can be made even smoother.

  As described above, according to the light emitting device 400 of this embodiment, when the light emitting structures 10 are arranged with different luminances, the luminance between the high luminance region and the low luminance region is increased. A luminance profile with fewer steps can be obtained, and a light-emitting device with excellent visibility can be provided.

  In the fourth embodiment, the case where the light emitting device 400 includes the light emitting structure 10D and the light emitting structure 10E has been described. However, the present invention is not limited to this. Of the exposed side surface 17W of the wavelength conversion member 17 of the light emitting structure 10, at least one side surface 17W may have a round shape. The light emitting structure 10A, the light emitting structure 10B, the light emitting structure 10C, and the light emitting structure in which the at least one side surface 17W has a round shape may be appropriately combined and arranged.

  In the fourth embodiment, the example in which the exposed side surface 17W of the wavelength conversion member 17 has a round shape has been described. However, as a modified example, the exposed side surface 17W of the wavelength conversion member 17 has a different shape. You may have a shape.

  FIG. 8A is a cross-sectional view showing a cross section along the X direction of a light emitting structure 10F which is a modification of the light emitting structure 10D of FIG. 6A. As shown in FIG. 8A, the exposed side surface 17W of the wavelength conversion member 17 of the light emitting structure 10F is inclined in the forward direction from the upper surface 17S of the wavelength conversion member 17 toward the upper surface 15S of the translucent substrate 15. Yes (forward tapered shape). The light emitting structure 400 may include a light emitting structure 10F instead of the light emitting structure 10D.

  In the above embodiment, when the light emitting structure 10 has the exposed side surface 17W of the wavelength conversion member 17 at the end in the X direction, the Y direction is a direction perpendicular to the X direction. The cross-sectional shape along the X direction of the covering member 19 at the end may have a cross-sectional shape similar to that of the wavelength conversion member 17 such as a round shape.

  FIG. 8B is a cross-sectional view showing a cross section along the X direction of a light emitting structure 10G which is a modification of the light emitting structure 10B. As shown in FIG. 8B, the light emitting structure 10G is different from the light emitting structure 10B in that the wavelength converting member 17 does not extend to the upper surface of the covering member 19 on the end side where the wavelength converting member 17 is exposed. .

  In the above embodiment, the light emitting structure 10G may be used instead of the light emitting structure 10B. Further, in the above embodiment, instead of the configuration in which the wavelength conversion member 17 extends to the upper surface of the covering member 19 at the exposed end of the wavelength conversion member 17, there is a configuration in which the wavelength conversion member 17 does not extend. You may do it.

  In the above-described embodiment, the configuration along the X direction of the light emitting structure 10 has been described. In addition, the side surface 17W where the wavelength conversion member 17 is exposed is also present at the end in the Y direction array. May be provided.

  The number of the light emitting structures 10 arranged in the X direction and the Y direction is not limited to the number shown in the above embodiment. For example, any number of light emitting structures 10 that are 2 or more in the X direction and 1 or more in the Y direction may be arranged.

  In the above-described embodiment, the example in which the light emitting structure 10 has a rectangular parallelepiped shape or a cubic shape has been described. However, the present invention is not limited to this. For example, the light emitting structure 10 may have other shapes such as a shape partially including a curved surface. good.

  As described above, according to the light emitting device of the present invention, when the plurality of light emitting structures are arranged and lit, the second covering structure in which the side surface of the wavelength conversion member is exposed at the end of the arrangement. By disposing the light emitting structure having the above, it is possible to obtain a luminance profile with a gradual change from the region irradiated by the light emitting device to the outer region. In addition, the light emitting structure having the second covering structure is arranged at a position other than the end of the array, and the change between the high luminance region and the low luminance region irradiated by the light emitting device is gentle. A luminance profile can be obtained. Accordingly, it is possible to provide a light-emitting device with less luminance difference between regions with different luminance and high visibility.

100, 200, 300, 400 Light-emitting device 10 Light-emitting structure 11 Mounting substrate 12 Semiconductor light-emitting element 13 Semiconductor structure layer 14A p-electrode 14
14B n electrode 15 Translucent substrate 17 Wavelength converting member 17S Upper surface 17W of wavelength converting member 17 Side surface 19 where wavelength converting member 17 is exposed Covering member

Claims (5)

A mounting substrate;
A plurality of light emitting structures that are juxtaposed on the mounting substrate and arranged in a first arrangement direction and a second arrangement direction that is perpendicular to the first arrangement direction;
Each of the plurality of light emitting structures includes a semiconductor light emitting element, and a wavelength conversion member formed on an upper surface of the semiconductor light emitting element,
At least one light emitting structure among the light emitting structures positioned at both ends in the first arrangement direction is:
Side surfaces of the semiconductor light emitting element and the wavelength conversion member facing the light emitting structure adjacent to each other in the first arrangement direction are covered with a covering member,
The light emitting device according to claim 1, wherein a side surface of the semiconductor light emitting element on an end side in the first arrangement direction is covered with the covering member, and a side surface of the wavelength conversion member is exposed. At least one of the light emitting structures in the first arrangement direction is:
Both sides of the semiconductor light emitting element facing the light emitting structure adjacent in the first arrangement direction are covered with the covering member, and at least one side surface of the wavelength converting member is exposed. The light emitting device according to claim 1. At least one of the light emitting structures in the first arrangement direction is:
The both side surfaces of the semiconductor light emitting element facing the light emitting structure adjacent in the first arrangement direction are covered with the covering member, and both side surfaces of the wavelength conversion member are exposed. Item 3. The light emitting device according to Item 1 or 2.   The cross-sectional shape along the first arrangement direction of at least one of the exposed side surfaces of the wavelength conversion member has a forward tapered shape or a round shape. The light emitting device according to item. A mounting substrate;
A light emitting structure disposed on the mounting substrate,
The light emitting structure includes a semiconductor light emitting element, and a wavelength conversion member formed on an upper surface of the semiconductor light emitting element,
The semiconductor light emitting device and the wavelength conversion member have four side surfaces,
The four side surfaces of the semiconductor light emitting element are covered with a covering member,
At least one of the four side surfaces of the wavelength conversion member is exposed, and the other side surface is covered with the covering member.

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