JP2017212309A - LED lighting device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an LED lighting device by which a uniform light emission effect of high brightness without light emission unevenness or variation can be achieved on the whole.SOLUTION: An LED lighting device comprises: a plurality of light-emitting elements 16; a mount substrate 12 having a mount face 15 on which the plurality of light-emitting elements 16 are mounted; and a reflective part 23 provided in the mount face for each light-emitting element to be mounted thereon, and surrounding the light-emitting element. The reflective part has an inclined plane 24 which is inclined downward toward the corresponding light-emitting element.SELECTED DRAWING: Figure 3

Description

  The present invention relates to an LED lighting device mounted on various lighting fixtures.

  In recent years, an illumination device using a plurality of light emitting elements has been adopted as a light source for illumination in place of a light bulb or a fluorescent lamp. The light emitting element consumes less power than a light bulb or the like, but has a narrow directivity because it is a point light source. For this reason, several tens to several hundreds of light emitting elements are used in the LED illumination device, and a light emitting surface with uniform brightness is formed by sealing these light emitting elements with a light-transmitting resin. doing.

  In the above light emitting element, there is a large amount of light emitted from the light emitting layer (PN junction portion) toward the upper surface of the mounting substrate, and thus there is a case where the luminance toward the front direction cannot be obtained sufficiently. In order to improve this, light emitted in the lateral direction is formed by forming a mounting substrate on which the LED is mounted with a material having high reflectivity, or by providing a reflecting member around the mounted light emitting element. Is reflected in the front direction to increase the brightness in the front direction.

  In Patent Document 1, the upper surface of the mounting substrate on which the light emitting element is mounted is formed into a rough surface including a set of fine irregularities, so that light traveling from the light emitting layer of the light emitting element toward the upper surface of the mounting substrate is directed in the front direction. A light emitting device configured to be directed is disclosed.

  In Patent Document 2, an electrode surface inclined at a predetermined angle is provided on an electrode surface on which a light emitting element is mounted, so that light directed from the light emitting layer of the light emitting element toward the upper surface of the mounting substrate is directed in the front direction. A light emitting device is disclosed.

JP 2009-289918 A JP 2010-171116 A

  In the light emitting device disclosed in Patent Document 1, the mounting surface of the mounting substrate on which the light emitting element is mounted is formed of a material having high light reflectance, or the mounting surface is formed to be a rough surface. Thus, it is possible to obtain a reflection effect toward the upper side of the mounting surface (light emitting front). However, simply selecting a member with high light reflectance or roughing the mounting surface has a problem in that the light reflectance toward the light-emitting front varies and uniform and high-luminance light emission cannot be obtained. .

  On the other hand, in the light emitting device disclosed in Patent Document 2, since it is necessary to provide a reflective surface that is inclined separately from the mounting substrate and the electrodes, a plurality of light emitting elements are concentrated on such a reflective surface. However, there is a problem in that it is difficult to manufacture on a mounting substrate disposed in a manner, and is not suitable for mass production.

  Accordingly, an object of the present invention is to improve the overall performance of a mounting board on which a plurality of light emitting elements are arranged and mounted by uniformly reflecting light emitted from the periphery of each light emitting element toward the upper side of the mounting board. It is an object of the present invention to provide an LED lighting device that can obtain a uniform light emitting effect without luminance unevenness and variation in luminance.

  In order to solve the above-described problems, an LED illumination device according to the present invention is an LED illumination device including a plurality of light emitting elements and a mounting substrate having a mounting surface on which the plurality of light emitting elements are mounted. Each mounted light emitting element is provided with a reflecting portion that takes in the periphery of the light emitting element, and the reflecting portion has an inclined surface that is inclined downward toward the respective light emitting elements.

  According to the LED illumination device of the present invention, the mounting surface on which the plurality of light emitting elements are mounted is provided so as to surround each light emitting element, and has an inclined surface that is inclined downward toward the light emitting element. Since it is formed by the reflecting portion, the light emitted from each light emitting element toward the mounting surface can be uniformly reflected upward of the mounting surface. Thereby, the upper part of the mounting surface can be illuminated with high brightness and uniformity by the light directly emitted upward from each light emitting element and the reflected light from the periphery of each light emitting element.

It is a perspective view centering on the mounting surface of the LED lighting apparatus of this invention. It is a perspective view which shows the whole said LED illuminating device. It is the top view (a) of the mounting surface of 1st Embodiment, AA sectional drawing (b), and BB sectional drawing (c). It is principal part sectional drawing of the mounting surface of 1st Embodiment. It is the top view (a) of the mounting surface of 2nd Embodiment, AA sectional drawing (b), BB sectional drawing (c). It is the top view (a) of the mounting surface of 3rd Embodiment, AA sectional drawing (b), BB sectional drawing (c). It is principal part sectional drawing of the mounting surface of 3rd Embodiment. It is the top view (a) of the mounting surface of 4th Embodiment, AA sectional drawing (b), and BB sectional drawing (c).

  FIG. 1 shows an LED illumination device 11 according to a first embodiment of the present invention. The LED lighting device 11 includes a mounting board 12 and a wiring board 13 disposed on the mounting board 12 and having a circular opening 14 at the center, and the mounting board exposed through the opening 14. On 12, a mounting surface 15 is formed in which a plurality of light emitting portions 21 including a light emitting device 16 and an inclined reflecting portion 23 surrounding the light emitting device 16 are continuous.

  The mounting substrate 12 is made of a metal material having a high light reflectance and thermal conductivity of about several tens to several tens of mm depending on the lighting application, the lighting scale, and the like, and the mounting surface 15 is provided at the center. It is done.

  The wiring board 13 is formed with a pair of electrode bands 14a and 14b along the edge of the opening 14. The electrode bands 14a and 14b are connected to a pair of electrode terminals 20a and 20b for electrical connection with the outside. Each is electrically connected. One of the pair of electrode strips 14a and 14b is an anode and the other is a cathode.

  The light emitting element 16 mounted on the mounting surface 15 uses blue light emitting elements of the same type and the same size made of a gallium nitride compound semiconductor in order to emit white light emission color for general illumination. This blue light-emitting element includes a substrate made of sapphire glass and a diffusion layer obtained by diffusing and growing an n-type semiconductor and a p-type semiconductor on the substrate. Each of the n-type semiconductor and the p-type semiconductor has an n-type electrode and a p-type electrode on the upper surface, and is electrically connected to each other through a wire 19. In the present embodiment, a plurality of light emitting elements 16 are formed by a plurality of array groups connected in series, and the light emitting elements 16 located at both ends of each array group are connected to one of the electrode bands 14a and 14b. Then, a predetermined current is applied to each array group via the pair of electrode terminals 20a and 20b.

  As shown in FIG. 2, a partition frame 17 made of an insulating resin is formed around the opening 14 along the upper surfaces of the electrode bands 14 a and 14 b of the wiring board 13 at a predetermined height. A sealing resin 18 having translucency is formed inside. The sealing resin 18 is formed by adding a predetermined amount of a fluorescent agent to a transparent resin base material. For example, an epoxy resin or a silicone resin base material is made of yttrium, aluminum, garnet, which is a raw material of fluorescent particles. It can be formed by mixing an appropriate amount of a fluorescent agent made of (YAG) or a dye as a raw material for pigment particles.

  Next, based on FIG.3 and FIG.4, the structure of the said mounting surface 15 is demonstrated. Here, FIG. 3A is a plan view of the mounting surface 15, and FIGS. 3B and 3C are an AA sectional view and a BB sectional view of the mounting surface 15. The plurality of light emitting portions 21 constituting the mounting surface 15 are all formed uniformly, and each light emitting portion 21 includes a bottom surface 22 on which the light emitting element 16 is mounted and a mortar-shaped inclined reflection surrounding the bottom surface 22. Part 23. For this reason, each light emitting section 21 constitutes an independent light emitting area as a single unit, and by assembling a plurality of the light emitting sections 21 on the mounting surface 15, the entire predetermined illumination area is brightly and uniformly formed. Can be illuminated. The bottom surface 22 of each light emitting unit 21 is provided at a position where the mounting substrate 12 is recessed in a square shape in the thickness direction, and the reflection unit 23 is formed in a square shape in plan view and mounted on the bottom surface 22. It is formed by four trapezoidal inclined surfaces 24 inclined downward toward the light emitting element 16. As shown in FIG. 4, each inclined surface 24 has an upper end 25 set at a position lower than the light emitting layer 16a of the light emitting element 16, and reflects light emitted downward from the light emitting layer 16a. It has become.

  As shown in FIG. 3, the mounting surface 15 is formed such that the light emitting portions 21 are continuous in a grid pattern in the vertical and horizontal directions. For this reason, the reflection part 23 of each light emission part 21 is connected with the reflection part 23 of the adjacent light emission part 21 by the ridgeline 26 formed in the upper end 25 of each inclined surface 24, and adjoins with this ridgeline 26 as a boundary. The light reflected by the light emitting element 16 of the light emitting section 21 does not affect each other.

  The mounting surface 15 can collectively form a plurality of light emitting portions 21 including the bottom surface 22 and the reflective portion 23 by etching the upper surface of the mounting substrate 12. In addition, the mounting substrate 12 can be formed using a mold formed along the concave and convex shape of the mounting surface 15 including the array of the plurality of light emitting portions 21.

  As shown in FIG. 4, the inclined surface 24 constituting the reflecting portion 23 of each light emitting portion 21 is 10 degrees to 25 degrees from the outer periphery in the four directions of the bottom surface 22 on which the light emitting element 16 is mounted. It is formed by an inclination angle. As shown in FIG. 4A, when the inclination angle α1 of the inclined surface 24 is 25 degrees, the light having the emission angle β1 in the range of about 50 degrees from the light emitting layer 16a of the light emitting element 16 is By being reflected in the vicinity of the upper end 25 of the inclined surface 24, it is possible to obtain a large amount of reflected light that is directed in a direction substantially directly above the mounting surface 15 (light emission front surface). On the other hand, as shown in FIG. 4B, when the inclination angle α2 of the inclined surface 23 is 10 degrees, the light having the emission angle β2 of about 20 degrees from the light emitting layer 16a of the light emitting element 16 is emitted. By being reflected by the inclined surface 24 close to the bottom surface 22, it is possible to obtain a large amount of reflected light toward the light emitting front surface.

  Thus, when the inclination angle of the inclined surface 24 is increased, the light emitted from the light emitting layer 16a of the light emitting element 16 is reflected toward the light emitting front surface at a position close to the upper end 25 of the inclined surface 24. On the contrary, when the inclination angle of the inclined surface 24 is reduced, the light emitted from the light emitting layer 16a of the light emitting element 16 is directed toward the light emitting front in the vicinity of the bottom surface 22 where the light emitting element 16 is mounted. Can be reflected. Therefore, as in this embodiment, by setting the inclination angle of the inclined surface 24 in the range of 10 degrees to 25 degrees, the reflected light heading toward the light emitting front is increased without any light emission loss in each light emitting section 21. Luminous efficiency can be increased.

  Since the mounting surface 15 of the present embodiment is configured by an aggregate of the light emitting portions 21 including the rectangular reflecting portions 23 in plan view, it is directly emitted from the light emitting element 16 mounted at the center of each reflecting portion 23. The light and the reflected light having a square light emission contour from each reflecting portion 23 are combined, and the front surface of the light emission can be illuminated with high brightness without unevenness.

  FIG. 5 shows a configuration example of the mounting surface 30 of the second embodiment. The mounting surface 30 of this embodiment is formed by an aggregate of light emitting portions 31 including a bottom surface 32 on which the light emitting element 16 is mounted and a circular mortar-shaped reflecting portion 33 surrounding the bottom surface 32. For this reason, each light emitting unit 31 constitutes an independent light emitting area as a single unit, and a plurality of the light emitting units 31 are assembled on the mounting surface 30 to make the entire predetermined illumination area bright and uniform. Can be illuminated.

  As in the first embodiment, the light reflecting element 33 is formed between the top surface 35 of the inclined surface 34 by forming the inclination angle of the inclined surface 34 in the range of 10 degrees to 25 degrees. Reflected light traveling toward the front surface of the light emitting layer 16a can be obtained by directing light emitted downward from the light emitting layer 16a at a predetermined angle with respect to the mounting surface 30.

  In each of the light emitting portions 31, the reflecting portion 33 is formed in a circular shape in plan view with the light emitting element 16 as the center, so that the bottom surface 32 on which the light emitting element 16 is mounted is shifted by a half space as shown in FIG. By arranging in this way, more light emitting elements 16 can be integrated in the mounting surface 30. With this arrangement, the reflecting portions 33 of each light emitting portion 31 are connected to each other by the arc-shaped ridge line 36 in contact with the reflecting portion 33 of the adjacent light emitting portion 31 and the upper end 35 of each inclined surface 34. Therefore, the light reflected by the light emitting elements 16 of the adjacent light emitting sections 31 does not affect each other.

  In the present embodiment, the reflecting portion 33 of each light emitting portion 31 is formed by the circular inclined surface 34 centering on the light emitting element 16, so that the inclined surface within the same range from the light emitting layer 16 a of the light emitting element 16. All the light reflected by 34 can be reflected at the same angle. For this reason, concentric light emission centering on the light emitting element 16 is obtained from each light emitting part 31, and this concentric light emission spreads over the entire mounting surface 30 to illuminate the light emission front surface with uniform and high luminance light. can do.

  FIG. 6 shows a configuration example of the mounting surface 40 of the third embodiment. The mounting surface 40 of this embodiment is formed by an aggregate of light emitting portions 41 including a bottom surface 42 on which the light emitting element 16 is mounted and a reflecting portion 43 having a function as a Fresnel lens surrounding the bottom surface 42. . Each of the light emitting units 41 constitutes a single independent light emitting area, and a plurality of the light emitting units 41 are assembled on the mounting surface 40 to illuminate the entire predetermined illumination area brightly and uniformly. be able to.

  As shown in FIG. 7, the reflecting portion 43 is formed with a continuous small inclined surface 44 inclined downward toward each light emitting element 16, and one Fresnel is formed between the adjacent light emitting elements 16. A lens surface is formed. The inclination angle of each inclined surface 44 is set to a range of 10 degrees to 25 degrees as in the first and second embodiments.

  Each of the plurality of inclined surfaces 44 spreads in a stepped manner centering on the light emitting element 16, and an upper end 45 of the inclined surface 44 positioned on the outermost side of each light emitting unit 41 is connected to another adjacent light emitting unit 41. It is a continuous ridgeline 46 that divides the reflective area.

  The light emitted from the light emitting layer 16 a of each light emitting element 16 is reflected by the plurality of inclined surfaces 44, so that a large amount of light can be reflected toward the light emitting front surface that is substantially directly above the mounting surface 40. Further, since the inclination direction of the plurality of inclined surfaces 44 is reversed with respect to the ridge line 46, the reflected light does not interfere with the adjacent light emitting elements 16. For this reason, even when a plurality of light emitting portions 41 are continuously formed on the mounting surface 40, the reflective regions do not overlap between the adjacent light emitting elements 16, so that the brightness at the front surface of the light emission is made uniform. be able to.

  FIG. 8 shows a configuration example of the mounting surface 50 of the fourth embodiment. In the mounting surface 50 of this embodiment, the reflecting portion 53 surrounding the light emitting element 16 mounted on the bottom surface 52 is formed in a circle in plan view, and a plurality of minute inclined surfaces 54 similar to FIG. 7 are arranged concentrically. Is. For this reason, each light-emitting part 51 constitutes one independent light-emitting area as a single unit, and a plurality of the light-emitting parts 51 are gathered on the mounting surface 50 to make the entire predetermined illumination area bright and uniform. Can be illuminated.

  Since the shapes and angles of the plurality of inclined surfaces 54 constituting the reflecting portion 53 are the same as those in the embodiment shown in FIG. In this embodiment, in order to arrange the light emitting part 51 in close contact with the mounting surface 50 without a gap, as shown in FIG. 5, the light emitting elements 16 adjacent in the vertical and horizontal directions are shifted by a half space. In the present embodiment, concentric and highly condensed reflected light with the light emitting element 16 as the center is obtained from each light emitting portion 51, and the concentric reflected light spreads over the entire mounting surface 50, so Can be illuminated with uniform and high brightness light.

  Each of the plurality of inclined surfaces 54 extends concentrically around the light emitting element 16, and the upper end 55 of the inclined surface 54 located on the outermost side of each light emitting unit 51 reflects from the adjacent light emitting unit 51. It is a continuous ridge line 56 that divides the region.

  As described above, in the LED lighting device of the present invention, the mounting surface is formed by the assembly of the independent light emitting parts including the light emitting element and the reflective part surrounding the light emitting element. There is no variation in the light emitted from the light emitting portion, and uniform light emission with high brightness can be obtained over the entire mounting surface. In addition, the reflecting portion surrounding the light emitting element has an inclined surface whose angle is set so that the light emitted downward from the light emitting layer of the light emitting element is directed to the light emitting front surface that is substantially directly above the mounting surface. It is possible to obtain an illumination effect with a high light collecting property.

DESCRIPTION OF SYMBOLS 11 LED illuminating device 12 Mounting board 13 Wiring board 14 Opening part 14a, 14b Electrode band 15 Mounting surface 16 Light emitting element 16a Light emitting layer 17 Partition frame 18 Sealing resin 19 Wire 20a, 20b Electrode terminal 21 Light emitting part 22 Bottom face 23 Reflecting part 24 Inclined surface 25 Upper end 26 Ridge line 30 Mounting surface 31 Light emitting portion 32 Bottom surface 33 Reflecting portion 34 Inclined surface 35 Upper end 36 Ridge line 40 Mounting surface 41 Light emitting portion 42 Bottom surface 43 Reflecting portion 44 Inclined surface 45 Upper end 46 Edge line 50 Mounting surface 51 Light emitting portion 52 Bottom surface 53 Reflecting part 54 Inclined surface 55 Upper end 56 Edge line

Claims (8)

In an LED lighting device including a plurality of light emitting elements and a mounting substrate having a mounting surface on which the plurality of light emitting elements are mounted.
The mounting surface is provided with a reflection part surrounding the periphery of the light emitting element for each light emitting element to be mounted, and the reflection part has an inclined surface inclined downward toward each light emitting element. LED lighting device.   The LED lighting device according to claim 1, wherein the reflecting portion is formed in a square shape or a circular shape in plan view, and a light emitting element is mounted at the center thereof.   The LED lighting device according to claim 1, wherein the reflecting portion is formed in a mortar shape, and a light emitting element is mounted at the center thereof.   The LED lighting device according to claim 1, wherein the inclined surface of the reflecting portion has an inclination angle that reflects light emitted obliquely downward from each light emitting element substantially upward.   The LED illumination device according to claim 4, wherein an inclination angle of the inclined surface is in a range of 10 degrees to 25 degrees.   The LED lighting device according to claim 1, wherein the reflection portion is connected to an adjacent reflection portion by a ridge line formed at an upper end of the inclined surface.   The LED lighting device according to any one of claims 1 to 3, wherein the reflection portion is lower than at least a height of a light emitting layer of a light emitting element mounted.   The LED lighting device according to claim 1, wherein the reflection portion is formed by a Fresnel lens surface including a plurality of minute inclined surfaces.

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