JP2014022055A - Light emitting device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a light emitting device with a wide light distribution range.SOLUTION: A light emitting device 10 according to one embodiment of the present invention has: a substrate 11 having a first region 11a, and a second annular region 11b surrounding the first region 11a; a first LED chip 12 arranged on the first region 11a of the substrate 11; a second LED chip 13 arranged on the second region 11b of the substrate 11; and an annular reflection member 14 for reflecting at least one part of light emitted from the second LED chip 13 to a side of the substrate 11.

Description

  The present invention relates to a light emitting device.

  As a light-emitting device having a conventional LED light source, one in which a light distribution range is expanded by reflecting a part of light emitted from an LED element inside is known (for example, see Patent Documents 1 to 3).

  According to the light emitting devices described in Patent Documents 1 to 3, a part of the light emitted from the LED element by the reflecting means such as a lens, a cover, a reflecting plate and the like provided above the LED light source (light emission direction). To reflect. Since the light reflected by the reflecting means travels to the side and below the LED light source, the light distribution range of the light emitting device is widened.

JP 2011-142060 A JP 2012-33330 A JP 2012-94320 A

  One of the objects of the present invention is to provide a light emitting device having a wide light distribution range.

  In order to achieve the above object, one embodiment of the present invention is arranged on a first region, a substrate having an annular second region surrounding the first region, and the first region of the substrate. The first LED chip, the second LED chip disposed on the second region of the substrate, and at least part of the light emitted from the second LED chip is reflected to the side of the substrate. An annular reflecting member is provided.

  In the light-emitting device, it is preferable that the second LED chip is a plurality of LED chips arranged in a ring shape on the second region.

  In the light-emitting device, the reflecting member is a cylindrical reflector in which a gradient of a tangent in a vertical section from the bottom on the substrate side toward the top is nearly horizontal with respect to the surface of the substrate, and the first LED The chip may be located inside the reflecting member, and the second LED chip may be located outside the reflecting member.

  In the light emitting device, it is preferable that the upper edge of the reflecting member has a waveform.

  In the light emitting device, the second LED chip and the reflecting member may be disposed on the same side of the substrate as the surface on which the first LED chip is disposed.

  In the light emitting device, the second LED chip and the reflection member may be disposed on a surface of the substrate opposite to a surface on which the first LED chip is disposed.

  In the light emitting device, the second region of the substrate may have a light transmitting property.

  In the above light-emitting device, the reflecting member is an annular prism lens having an inner diameter that is larger than the inner diameter of the bottom portion on the substrate side and having an inclined surface on the inner side, and the reflecting member is positioned above the second LED chip. May be.

  In the light emitting device, it is preferable that the bottom surface and the outer surface of the reflecting member on the substrate side have irregularities.

  According to another aspect of the present invention, there is provided a first region, a substrate having an annular second region surrounding the first region, and a first region disposed on the first region of the substrate. There is provided a light emitting device comprising: an LED chip; and a second LED chip disposed on the second region on a surface opposite to the surface on which the first LED chip of the substrate is disposed.

  According to another aspect of the present invention, there is provided a substrate having a first region, a translucent second annular region surrounding the first region, and the first region of the substrate. There is provided a light emitting device having a first LED chip disposed on the substrate and a second LED chip disposed on the second region of the substrate.

  According to the present invention, a light emitting device having a wide light distribution range can be provided.

FIGS. 1A and 1B are top views of the light emitting device according to the first embodiment. 2A and 2B are vertical cross-sectional views of the light-emitting device taken along line AA in FIG. FIGS. 3A and 3B are diagrams schematically showing a locus of light emitted from the second LED chip and reflected by the reflecting member. FIG. 4 is a top view of the light emitting device according to the second embodiment. 5A and 5B are vertical cross-sectional views of the light emitting device 20 taken along line BB in FIG. 4A. FIG. 6 is a diagram schematically showing a locus of light emitted from the second LED chip and reflected by the reflecting member. 7A and 7B are vertical sectional views of the light emitting device according to the third embodiment. FIGS. 8A and 8B are vertical sectional views of the light emitting device according to the fourth embodiment.

[First Embodiment]
1A and 1B are top views of the light emitting device 10 according to the first embodiment. 2A and 2B are vertical cross-sectional views of the light emitting device 10 taken along line AA in FIG.

  The light emitting device 10 is provided on the upper surface of the substrate 11, the first LED chip 12 and the second LED chip 13 disposed on the upper surface of the substrate 11 (the upper surface in FIG. 2), and the substrate 11. An annular reflecting member 14, a diffusion cover 15 that covers the upper side of the substrate 11 (upward in FIG. 2), and a heat sink 16 that is provided on the lower surface (lower surface of FIG. 2) side of the substrate 11.

  In addition, illustration of the diffusion cover 15 is abbreviate | omitted in FIG. 1 (a), (b). Further, in FIG. 1B, the illustration of the reflecting member 14 is omitted, and a dotted line in the drawing is a region on the substrate 11 immediately below the bottom surface of the reflecting member 14 (when the reflecting member 14 is in contact with the substrate 11, the reflecting member 14 is reflected). This represents a region on the substrate 11 where the bottom surface of the member 14 contacts. A light-emitting device 10 shown in FIG. 2B is a modification of the light-emitting device 10 shown in FIG. 2A, and the vertical cross-sectional shapes of the reflecting member 14 and the diffusion cover 15 are different.

  The light emitting device 10 is, for example, a light engine. In this case, the light emitting device 10 includes a power supply circuit (not shown).

  The substrate 11 has a circular first region 11a and an annular second region 11b surrounding the first region 11a. The first region 11 a is a region where the first LED chip 12 is disposed, and is a region inside a region immediately below the bottom surface of the annular reflecting member 14. The second area 11 b is an area where the second LED chip 13 is disposed, and is an area outside the area immediately below the bottom surface of the annular reflecting member 14.

  The substrate 11 has a wiring (not shown) connected to the first LED chip 12 and the second LED chip 13, and an electrode (not shown) is connected to the wiring. Power is supplied to the first LED chip 12 and the second LED chip 13 through the electrodes and the wiring of the substrate 11.

  The first LED chip 12 is disposed on the first region 11 a, and light emitted from the first LED chip 12 is emitted above the substrate 11. A part of the light emitted from the first LED chip 12 may be reflected above the substrate 11 by the inner side surface of the reflecting member 14.

  Although the number of the first LED chips 12 is not limited, a plurality of first LED chips 12 are used for suppressing variation in the light distribution of the light emitting device 10 and for uniform light emission (reduction in graininess) when the light emitting device 10 is viewed from above. The first LED chips 12 are preferably distributed on the first region 11a. In this case, in order to further reduce the variation in the light distribution of the light emitting device 10, the plurality of first LED chips 12 may be installed in an arrangement having rotational symmetry about the center of the substrate 11. preferable.

  The second LED chip 13 is disposed on the second region 11b, and at least part of the light emitted from the second LED chip 13 is laterally formed by the outer surface of the reflecting member 14 (see FIG. 2). In the lateral direction) and further downward (downward in FIG. 2).

  The number of the second LED chips 13 is not limited, but a plurality of second LED chips 13 are annularly distributed on the second region 11b in order to suppress variations in the light distribution of the light emitting device 10. Is preferred. In this case, in order to further reduce variations in the light distribution of the light emitting device 10, the plurality of second LED chips 13 may be installed in an arrangement having rotational symmetry about the center of the substrate 11. preferable.

  The reflecting member 14 is a cylindrical reflector in which the gradient of the tangent in the vertical cross section from the bottom on the substrate 11 side toward the top is nearly horizontal with respect to the surface of the substrate 11. The reflecting member 14 is made of a non-translucent material, for example, a white resin material. The reflecting member 14 is disposed on the upper surface of the substrate 11 so as to surround the first LED chip 12. The first LED chip 12 is located inside the reflecting member 14, and the second LED chip 13 is located outside the reflecting member 14.

  The reflecting member 14 may have a shape in which the vertical cross-sectional shape is a curve as shown in FIG. 2 (a), or the vertical cross-sectional shape is a straight line as shown in FIG. 2 (b). You may have the shape comprised by.

  As shown in FIG. 1, the upper edge of the reflecting member 14 is preferably corrugated. Since the upper edge of the reflecting member 14 is corrugated, a part of light emitted upward from the second LED chip 13 is reflected by the corrugated convex part 14a, and the other part of the light is corrugated concave part 14b. Pass through through. For this reason, the light / dark difference of the light on the reflection member 14 reduces, and the outline of the reflection member 14 becomes difficult to visually recognize from the outer side of the light-emitting device 10.

  FIG. 3 is a diagram schematically showing a trajectory of light emitted from the second LED chip 13 and reflected by the reflecting member 14. 3A shows a light locus on a vertical surface including the convex portion 14a of the reflecting member 14, and FIG. 3B shows a light locus on a vertical surface including the concave portion 14b of the reflecting member 14. . As shown in FIGS. 3A and 3B, the light emitted from the second LED chip 13 is emitted from the vertical surface including the convex portion 14a and the vertical surface including the concave portion 14b of the reflecting member 14. The range is different.

  The waveform of the upper edge of the reflecting member 14 may be configured by either a curve or a straight line, but is preferably configured by a curve in order to smooth the gradation of light extracted from the light emitting device 10.

  The diffusion cover 15 can diffuse light emitted from the first LED chip 12 and the second LED chip 13 and suppress variation in the light emission distribution of the light emitting device 10.

  Note that when the plurality of first LED chips 12 and the second LED chips 13 are distributed on the substrate 11, variation in the light emission distribution is reduced. Therefore, the transmittance of the diffusion cover 15 is increased to increase the transmittance. 10 can be increased, or the distance between the diffusion cover 15 and the substrate 11 can be shortened to make the light emitting device 10 thinner.

  The shape of the diffusion cover 15 is not limited to a specific shape, and as shown in FIG. 2 (a), the vertical cross-sectional shape may have a shape constituted by a curve, or as shown in FIG. 2 (b). As shown, the vertical cross-sectional shape may have a shape constituted by a straight line.

  The heat sink 16 has a function of releasing heat generated from the first LED chip 12 and the second LED chip 13 to the outside. Heat generated from the first LED chip 12 and the second LED chip 13 is transmitted to the heat sink 16 through the substrate 11 and is radiated.

[Second Embodiment]
The second embodiment differs from the first embodiment in the configuration of the reflecting member. Note that the description of the same points as in the first embodiment will be omitted or simplified.

  FIG. 4 is a top view of the light emitting device 20 according to the second embodiment. 5A and 5B are vertical sectional views of the light emitting device 20 taken along line BB in FIG.

  The light emitting device 20 includes a substrate 11, a first LED chip 12 and a second LED chip 13 disposed on the upper surface of the substrate 11, an annular reflecting member 24 provided on the upper surface of the substrate 11, and a substrate. 11 and a heat sink 16 provided on the lower surface side of the substrate 11.

  In FIG. 4, the diffusion cover 15 is not shown. The light emitting device 20 shown in FIG. 5B is a modification of the light emitting device 20 shown in FIG. 5A, and the vertical cross-sectional shape of the reflecting member 24 is different.

  The first LED chip 12 is disposed on the first region 11 a, and the light emitted from the first LED chip 12 is emitted above the substrate 11 through the inside of the annular reflecting member 24.

  The second LED chip 13 is arranged on the second region 11b, and at least a part of the light emitted from the second LED chip 13 is laterally formed on the side of the substrate 11 by the inclined surface 24c inside the reflecting member 24. Is reflected downward.

  The reflection member 24 is an annular prism lens having an upper inner diameter larger than the inner diameter of the bottom portion on the substrate 11 side and having an inclined surface 24c on the inner side. The reflecting member 24 is made of a transmissive material such as an acrylic resin. The reflection member 24 is installed above the second region 11b, that is, above the second LED chip 13. The reflecting member 24 is supported on the substrate 11 by the leg portion 24d. Note that when the reflecting member 24 is held above the second LED chip 13 by other means, the leg portion 24d may not be provided.

  The bottom surface 24 a and the outer surface 24 b on the substrate 11 side of the reflecting member 24 preferably have irregularities formed by embossing or the like in order to suppress luminance unevenness and chromaticity unevenness of light emission of the light emitting device 20.

  As shown in FIGS. 5A and 5B, the reflecting member 24 is preferably configured such that the inclined surface 24c is composed of two or more surfaces having different inclination angles. A surface with a large inclination angle reflects light from below, and a surface with a small inclination angle reflects light from the side. By configuring the outside of the outer slope 24c as a surface with a large inclination angle and the inside as a surface with a small inclination angle, the light incident on the outside of the reflecting member 24 is reflected downward, and the light incident on the inside is efficiently reflected. Can be injected outside.

  Further, as shown in FIG. 5B, the reflecting member 24 may have a reflecting film 26 on all or a part of the inclined surface 24c, for example, a surface having a small inclination angle through which light is easily transmitted. . The reflective film 26 is, for example, a diffusion sheet or a reflective tape.

  FIG. 6 is a diagram schematically illustrating a trajectory of light emitted from the second LED chip 13 and reflected by the reflecting member 24. As shown in FIG. 6, the light emitted from the second LED chip 13 enters the reflecting member 24 from the bottom surface 24a, is reflected by the inclined surface 24c, and is emitted from the bottom surface 24a or the outer surface 24b. In FIG. 6, the illustration of light transmitted through the inclined surface 24c is omitted. By providing the reflective film 26 on the slope 24c, the reflectance at the slope 24c can be improved.

[Third Embodiment]
The third embodiment differs from the first embodiment in the arrangement of the second LED chip. Note that the description of the same points as in the first embodiment will be omitted or simplified.

  FIG. 7A is a vertical sectional view of the light emitting device 30 according to the third embodiment. The light emitting device 30 includes a substrate 11, a first LED chip 12 disposed on the upper surface of the substrate 11, and a second LED chip 13 disposed on the lower surface of the substrate 11 (the lower surface in FIG. 2). And a diffusion cover 15 covering the upper side of the substrate 11 and a heat sink 16 provided on the lower surface side of the substrate 11.

  Further, the light emitting device 30 may have an annular reflecting member 14 as shown in FIG. The annular reflecting member 14 is the same as that of the first embodiment, but is installed on the lower surface of the substrate 11. The first LED chip 12 is located inside the reflecting member 14 on the upper surface of the substrate 11. The second LED chip 13 is located outside the reflecting member 14 on the lower surface of the substrate 11.

  The first LED chip 12 is disposed on the first region 11 a on the upper surface of the substrate 11, and light emitted from the first LED chip 12 is emitted above the substrate 11.

  The second LED chip 13 is disposed on the second region 11 b on the lower surface of the substrate 11, and light emitted from the second LED chip 13 is emitted to the side and below the substrate 11. When the annular reflecting member 14 is installed, at least a part of the light emitted from the second LED chip 13 is reflected to the side of the substrate 11 by the outer surface of the reflecting member 14.

[Fourth Embodiment]
The fourth embodiment differs from the first embodiment in the configuration of the substrate. Note that the description of the same points as in the first embodiment will be omitted or simplified.

  FIG. 8A is a vertical sectional view of the light emitting device 40 according to the fourth embodiment. The light emitting device 40 includes a substrate 41, a first LED chip 12 and a second LED chip 43 disposed on the upper surface of the substrate 41, a diffusion cover 15 that covers the upper side of the substrate 41, and a lower surface side of the substrate 41. And a heat sink 16 provided.

  Moreover, the light-emitting device 40 may have an annular reflecting member 14 as shown in FIG. The annular reflecting member 14 is the same as that of the first embodiment, but is installed on the lower surface of the substrate 41. The first LED chip 12 is located inside the reflecting member 14 on the upper surface of the substrate 41. The second LED chip 43 is located outside the reflecting member 14 on the upper surface of the substrate 41.

  The substrate 41 has a first region 41a and an annular second region 41b surrounding the first region 41a. The first region 41a is the same as the first region 11a of the substrate 11 of the first embodiment, but the second region 41b is made of a light-transmitting material, and is particularly a glass having excellent heat resistance. It is preferably made of a translucent inorganic material such as transparent ceramic.

  The first LED chip 12 is disposed on the first region 41 a on the upper surface of the substrate 41, and light emitted from the first LED chip 12 is emitted above the substrate 41.

  The second LED chip 43 is an LED chip that emits light not only above but also toward the substrate 41 (for example, an LED chip in which the chip substrate has translucency and does not include a reflective layer). The second LED chip 43 is disposed on the second region 41b on the upper surface of the substrate 41, and light emitted from the second LED chip 43 toward the substrate 41 passes through the second region 41b, and the substrate 41 Are injected sideways and downward.

  When the annular reflecting member 14 is installed, at least a part of the light emitted from the second LED chip 43 to the substrate 41 side is reflected to the side of the substrate 41 by the outer surface of the reflecting member 14.

  The reflection member 14 may be installed on the upper surface of the substrate 41. In this case, a part of the light emitted from the second LED chip 43 to the upper side of the substrate 41 is reflected to the side and the lower side of the substrate 41 by the outer surface of the reflecting member 14, and the light emitted to the substrate 41 side is 2 is transmitted through the region 41 b and injected laterally and downward of the substrate 41.

  Further, the second LED chip 43 may be disposed on the lower surface of the substrate 41, and the reflecting member 14 may be disposed on the upper surface of the substrate 41. In this case, the light emitted from the second LED chip 43 toward the substrate 41 passes through the second region 41 b and travels upward, and at least a part of the light is laterally directed to the substrate 41 by the outer surface of the reflecting member 14. Reflected.

  Further, the reflecting member 14 may be installed on both the upper surface and the lower surface of the substrate 41. In this case, the second LED chip 43 may be installed on either the upper surface or the lower surface.

(Effect of embodiment)
According to the first to fourth embodiments, the light emitted from the first LED chip is taken out above the light emitting device (above the substrate), and the light emitted from the second LED chip is taken to the light emitting device side. (Side of the substrate) and further downward. For this reason, the light emitting device can emit light over a wide range.

  Further, in the light emitting devices of the first to fourth embodiments, it is possible to disperse the plurality of first LED chips and the second LED chips on the substrate and reduce the variation in the light emission distribution. The light transmittance of the light emitting device can be increased by increasing the transmittance of the diffusion cover, or the light emitting device can be made thinner by shortening the distance between the diffusion cover and the substrate.

  The present invention is not limited to the above-described embodiment, and various modifications can be made without departing from the spirit of the invention. For example, in the above embodiment, a light emitting device having a circular planar shape is illustrated, but the planar shape of the light emitting device is not limited to a circular shape. For example, when the planar shape of the light emitting device is a polygon, the first region of the substrate is a polygon, and the second region of the substrate and the reflecting member are polygonal rings.

  In addition, the constituent elements of the above-described embodiment can be arbitrarily combined without departing from the spirit of the invention.

  Moreover, said embodiment does not limit the invention which concerns on a claim. In addition, it should be noted that not all the combinations of features described in the embodiments are essential to the means for solving the problems of the invention.

10, 20, 30, 40 Light-emitting device 11, 41 Substrate 11a, 41a 1st area | region 11b, 41b 2nd area | region 12 1st LED chip 13 2nd LED chip 14, 24 Reflective member 14a Convex part 14b Concave part 24a Bottom 24b Outer side 24c Slope

Claims (11)

A substrate having a first region and an annular second region surrounding the first region;
A first LED chip disposed on the first region of the substrate;
A second LED chip disposed on the second region of the substrate;
An annular reflecting member that reflects at least a part of the light emitted from the second LED chip to the side of the substrate;
A light emitting device. The second LED chip is a plurality of LED chips arranged in an annular shape on the second region.
The light emitting device according to claim 1. The reflecting member is a cylindrical reflector in which a gradient of a tangent in a vertical section from the bottom on the substrate side toward the top is nearly horizontal with respect to the surface of the substrate,
The first LED chip is located inside the reflective member;
The second LED chip is located outside the reflective member;
The light emitting device according to claim 1. The upper edge of the reflective member is corrugated;
The light emitting device according to claim 3. The second LED chip and the reflecting member are disposed on a surface of the substrate on the same side as the surface on which the first LED chip is disposed;
The light emitting device according to claim 3 or 4. The second LED chip and the reflecting member are disposed on a surface of the substrate opposite to the surface on which the first LED chip is disposed;
The light emitting device according to claim 3 or 4. The second region of the substrate is translucent;
The light emitting device according to any one of claims 3 to 6. The reflecting member is an annular prism lens having a slope on the inside, the inner diameter of the upper part being larger than the inner diameter of the bottom part on the substrate side
The reflective member is located above the second LED chip;
The light emitting device according to claim 1. The bottom surface and the outer surface of the reflecting member on the substrate side have irregularities,
The light emitting device according to claim 8. A substrate having a first region and an annular second region surrounding the first region;
A first LED chip disposed on the first region of the substrate;
A second LED chip disposed on the second region of the surface opposite to the surface on which the first LED chip of the substrate is disposed;
A light emitting device. A first region and a substrate having translucency and having an annular second region surrounding the first region;
A first LED chip disposed on the first region of the substrate;
A second LED chip disposed on the second region of the substrate;
A light emitting device.

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