JP6685738B2 - Light emitting device - Google Patents

Description

  The present invention relates to a light emitting device in which a light emitting element is sealed with a sealing resin.

  In recent years, a light emitting device including a light emitting element has been widely used as a light source for a lighting fixture or a liquid crystal display. In the light emitting device, specifically, a light emitting element that emits blue light is sealed with a sealing resin containing fluorescent materials of a plurality of colors (for example, red and green) which are wavelength conversion materials, and white light is emitted. It is designed to emit light. Even if a lighting fixture is configured with such a light emitting device, the color tone cannot be adjusted because the color tone of white light is the same. In recent years, there has been a demand for a light emitting device capable of changing the color tone to change the effect according to the season.

  Therefore, a large number of light emitting elements that emit blue light are mounted in series on the substrate at predetermined intervals and the light emitting element groups are arranged in multiple rows in the Y direction. Then, the light emitting element groups in the first and second rows in the Y direction are sealed with a first sealing resin containing a phosphor that emits light of a bulb color, and the third and fourth rows in the Y direction are sealed. Is encapsulated with a second encapsulating resin containing a phosphor that emits daylight white light, and this is alternately repeated to provide a large number of light emitting element groups that emit two kinds of hues. . A part of these light emitting element groups emits light, the other light emitting element groups are turned off, or all the light emitting element groups are turned on, so that the hue can be changed by changing the light emitting pattern. (For example, refer to Patent Document 1).

JP, 2014-49504, A

  In the light emitting device of Patent Document 1, two types of sealing resins have to be alternately sealed, so that a gap is required between the sealing resins, and the entire light emitting device becomes large. .

  In view of the above-mentioned situation, the present invention aims to provide a light emitting device that can be downsized.

In order to solve the above problems, the light emitting device of the present invention outputs a light emission wavelength in the visible light region and seals the light emitting element with a plurality of types of light emitting elements having different light distribution characteristics that are the angular distribution of light. sealed, and the same made of a translucent material containing a single color or multiple color phosphors for emitting light of a different color from the emission color of the light emitting element is excited by the light emitted from the light emitting element comprising a sealing resin, wherein the plurality of types of light emitting devices includes a first light emitting element angular distribution of light is wide, and a angular distribution of light is narrow second light emitting element, from a surface of said sealing resin The distance to the irradiation surface of the second light emitting element is shorter than the distance from the surface of the sealing resin to the irradiation surface of the first light emitting element .

  According to the above configuration, by providing a plurality of types of light emitting elements having different light distribution characteristics that are the angular distribution of light, even if the same sealing resin, from one light emitting element having different light distribution characteristics to the sealing resin The amount of light shining on the phosphor contained in the phosphor is different from the amount of light shining on the phosphor contained in the sealing resin from the other light emitting element having different light distribution characteristics. From this, the hue of light emitted from one light emitting element and the hue of light emitted from the other light emitting element sealed by the same sealing resin can be made different. The difference in the light distribution characteristics means the light distribution characteristics in a wide range of the light angle distribution and the light distribution characteristics in a narrow range of the light angle distribution. Therefore, a light emitting device capable of emitting light of different colors can be configured by simply sealing a plurality of types of light emitting elements having different light distribution characteristics with the same sealing resin.

  Further, in the light emitting device of the present invention, the emission wavelength has a peak wavelength in the range of 380 nm to 470 nm, and the phosphor is composed of a phosphor that converts light emitted from the light emitting element into white light. May be.

  As described above, by converting the light emitted from the light emitting element into white light with the phosphor, the hue of the white light emitted from one light emitting element and the hue of the white light emitted from the other light emitting element are different. Can be made.

  According to the present invention, by providing a plurality of types of light emitting elements having different light distribution characteristics, it is possible to change the color shade of light even with the same sealing resin, so that it is possible to achieve miniaturization. A device can be provided.

The 1st Embodiment of the light-emitting device of this invention is shown, (a) is a top view, (b) is a longitudinal cross-sectional view, (c) is a longitudinal cross-sectional view showing a state in which the light-emitting element on the right side is caused to emit light, (d) FIG. 3 is a vertical cross-sectional view showing a state in which the left light emitting element is made to emit light. It is a graph which shows the emission spectrum of the same light-emitting device. The 2nd Embodiment of the light-emitting device of this invention is shown, (a) is a longitudinal cross-sectional view, (b) is a longitudinal cross-sectional view which shows the state which made the right light-emitting element light-emit, (c) light-emits the left light-emitting element. It is a longitudinal cross-sectional view which shows the state made to do. It is a graph which shows the emission spectrum of the same light-emitting device. The 3rd Embodiment of the light-emitting device of this invention is shown, (a) is a longitudinal cross-sectional view, (b) is a longitudinal cross-sectional view which shows the state which made the right light-emitting element light-emit, (c) light-emits the left light-emitting element. It is a longitudinal cross-sectional view which shows the state made to do. It is a graph which shows the emission spectrum of the same light-emitting device. The 4th Embodiment of the light-emitting device of this invention is shown, (a) is a longitudinal cross-sectional view, (b) is a longitudinal cross-sectional view which shows the state which made the right light-emitting element light-emit, (c) light-emits the left light-emitting element. It is a longitudinal cross-sectional view which shows the state made to do. 7 is a graph showing an emission spectrum of a light emitting device having another configuration that emits light other than white.

<First Embodiment>
1A, 1B, 1C, and 1D show a light emitting diode 1 which is an example of a light emitting device. The light emitting diode 1 includes a package 3 having a recess 2 formed therein, two light emitting elements 5 and 6 mounted on an upper surface 4 of a substrate 10 which will be described later and serves as a bottom surface of the recess 2, and two light emitting elements 5, 5. A sealing resin (for example, a silicone resin or an epoxy resin) 7 made of a translucent material for sealing 6 is provided. Here, the case where two light emitting elements 5 and 6 are provided in the concave portion 2 is shown, but it is also possible to provide three or four or more light emitting elements. The positive electrode and the negative electrode of each of the light emitting elements 5 or 6 are connected to the positive electrode and the negative electrode provided in the recess 2 via bonding wires 8, respectively.

  The recess 2 is composed of a bottom surface 4 and a peripheral side wall 9 having a tapered surface that rises from the outer peripheral edge of the bottom surface 4 to an upper opening and expands toward the opening side. The bottom surface 4 is made of a glass epoxy resin substrate. It is composed of a flat plate member 10 having a substantially square shape in plan view (may be a rectangle, a circle, or a polygon), and the peripheral side wall 9 is formed by stacking a large number of glass epoxy resin substrates in the vertical direction. Is formed by forming a through hole at the center of a rectangular parallelepiped having a square shape (which may be a rectangle, a circle, or a polygon) in plan view, and the peripheral side wall 9 thus configured is placed on the substrate 10. Then, the package 3 is constructed by integrating the two. Therefore, the peripheral side wall 9 is configured so as to surround the light emitting elements 5 and 6 and function as a reflector capable of condensing the light from the light emitting elements 5 and 6 toward the front of the upper opening. The package 3 is not limited to being manufactured by laminating a large number of glass epoxy resin substrates as described above, but may be electrically connected to the pad portion on which the light emitting element is mounted and the light emitting element mounted on the pad portion. It may be manufactured by molding a lead frame having lead parts to be connected with resin.

  The two light emitting elements 5 and 6 output light having a peak wavelength in the range of 380 nm to 470 nm, specifically, blue wavelengths (wavelengths including purple), and an arrangement of light having an angular distribution. It is composed of light emitting elements having different light characteristics. Specifically, one light emitting element 5 located on the left side of FIGS. 1A to 1D uses colorless and transparent sapphire as a base on which a light emitting layer that emits light is mounted. Since the emitted light is transmitted through the peripheral side surface of the colorless and transparent sapphire, 180 degrees in the light emitting state shown in FIG. 1D (this angle is determined by the light emitting element 5 to be manufactured and is limited to 180 degrees. It emits light up to an angle that is more than Therefore, the first light emitting element 5 having a wide light angle distribution is configured. Further, in the other light emitting element 6 located on the right side of FIGS. 1A to 1D, silicon (Si) is used as a base on which a light emitting layer that emits light is mounted, and light is emitted from the light emitting layer. Since light cannot pass through silicon, in the light emitting state of FIG. 1C, only an angle of about 100 degrees (this angle is determined by the light emitting element 6 to be manufactured and is not limited to about 100 degrees). Does not emit light. For this reason, the second light emitting element 6 having a narrower angular distribution of light than the first light emitting element 5 is configured.

  The encapsulating resin 7 contains phosphors of a plurality of colors for emitting white light by being excited by the light emitted from the light emitting elements 5 and 6 and emitting light of a color different from the emission color of the light emitting elements. is doing. Here, by using red and green phosphors or yellow and red phosphors, the light emitted from the sealing resin 7 emits white light. In order to adjust the color (obtain light of a desired color), phosphors of two types of colors are used, but phosphors of one type of color or three or more types of phosphors may be used.

  As described above, by providing a plurality of types (two types here) of light emitting elements having different light distribution characteristics that are the angular distribution of light, even if the same sealing resin 7 is used, the first light emitting element The amount of light from 5 to the phosphor contained in the sealing resin 7 is different from the amount of light from the second light emitting element 6 to the phosphor contained in the sealing resin 7. Here, the amount of light emitted from the second light emitting element 6 on the phosphor is smaller than the amount of light emitted from the first light emitting element 5 on the phosphor. From this, the hue of the white light emitted from the first light emitting element 5 and the hue of the white light emitted from the second light emitting element 6 which are sealed with the same sealing resin 7 can be made different.

  FIG. 2 shows an emission spectrum of light emitted from the two light emitting elements 5 and 6 shown in FIG. 1 after being converted by the phosphor. The emission spectrum shown by the solid line is from the first light emitting element 5, and the emission spectrum shown by the dotted line is from the second light emitting element 6. In FIG. 2, it can be seen that there is a clear difference in spectral shape in the wavelength band near 450 nm or in the wavelength band between 510 and 580 nm with respect to the intensity in the wavelength band near 600 nm, and there is a difference in hue.

<Second Embodiment>
In the first embodiment, the distance H1 from the surface 7A of the sealing resin 7 to the irradiation surface 5A of the first light emitting element 5 and the distance H2 from the surface 7A of the sealing resin 7 to the irradiation surface 6A of the second light emitting element 6. However, as shown in FIGS. 3A, 3B, and 3C, the distance H2 from the surface 7A of the sealing resin 7 to the irradiation surface 6A of the second light emitting element 6 is It is made shorter than the distance H1 from the surface 7A of the resin 7 to the irradiation surface 5A of the first light emitting element 5. In other words, the height from the top surface of the substrate 10 (the bottom surface 4) to the irradiation surface 6A of the second light emitting element 6 is from the top surface of the substrate 10 (the bottom surface 4) to the irradiation surface 5A of the first light emitting element 5. It is higher than the height. That is, the vertical dimension (height) of the second light emitting element 6 itself is set higher than the vertical dimension (height) of the first light emitting element 5 itself. With this configuration, it is possible to further reduce the amount of light that strikes the phosphor from the second light-emitting element 6 having a narrow angle distribution of light, and to reduce the change in the hue of white as compared with the configuration in which the height is the same. Can be large.

  FIG. 4 shows an emission spectrum of the light emitted from the two light emitting elements 5 and 6 shown in FIG. 3 after being converted by the phosphor. The emission spectrum shown by the solid line is from the first light emitting element 5, and the emission spectrum shown by the dotted line is from the second light emitting element 6. In FIG. 4, the first light emitting element 5 has a maximum peak in the vicinity of 600 nm, while the second light emitting element 6 has a maximum peak in the vicinity of 450 nm. This means that the size of the light emitting element is increased and the light emitted from the second light emitting element 6 to the phosphor is reduced, so that the amount of light in the light source wavelength range absorbed by the phosphor and the intensity of the light from the phosphor are reduced. However, it is shown that the intensity of the second light-emitting element 6 near the emission wavelength of 450 nm is relatively stronger than the emission wavelength of the phosphor near 600 nm. Also, regarding the wavelength band between 510 and 580 nm, the first light emitting element 5 and the second light emitting element 6 obviously have different spectrum shapes, and their relative intensities to the peak intensities near 600 nm are also different. As a result, a large difference can be made depending on the spectrum shape, and a difference can be made depending on the hue.

<Third Embodiment>
In FIGS. 3A, 3B, and 3C, the vertical dimension (height) of the second light emitting element 6 itself is higher than the vertical dimension (height) of the first light emitting element 5 itself. Although it is configured, as shown in FIGS. 5A, 5B, and 5C, the vertical dimension (height) of the second light emitting element 6 itself and the vertical dimension of the first light emitting element 5 itself. The height is the same (here, the dimensions are the same, but it may be different), and the upper surface 4A of a part of the upper surface 4 of the substrate 10 on which the second light emitting element 6 is mounted is partially formed. , Higher than the upper surface 4 of other parts. By doing so, the distance H2 from the surface 7A of the sealing resin 7 to the irradiation surface 6A of the second light emitting element 6 is the distance H1 from the surface of the sealing resin 7 to the irradiation surface 5A of the first light emitting element 5. I'm trying to be shorter than.

  FIG. 6 shows an emission spectrum of the light emitted from the two light emitting elements 5 and 6 shown in FIG. 5 after being converted by the phosphor. The emission spectrum shown by the solid line is from the first light emitting element 5, and the emission spectrum shown by the dotted line is from the second light emitting element 6. In FIG. 6, the first light emitting element 5 has a maximum peak near 600 nm, while the second light emitting element 6 has a maximum peak near 450 nm. This means that by reducing the distance from the second light emitting element 6 to the irradiation surface, the amount of light in the light source wavelength range absorbed by the phosphor and the intensity of light from the phosphor are reduced, and the second light emitting element is reduced. 6 shows that the intensity of No. 6 near the emission wavelength of 450 nm is relatively stronger than the emission wavelength of the phosphor near 600 nm. As a result, a large difference can be made depending on the spectrum shape, and a difference can be made depending on the hue.

  A plurality of light emitting diodes 1 configured by the first light emitting element 5 and the second light emitting element 6 configured as described above are arranged to form a light emitting element group to manufacture a lighting fixture, and a part of the light emitting element group emits light. However, the hue can be changed by changing the light emitting pattern such as turning off the other light emitting element groups or turning on all the light emitting element groups. Further, by controlling the currents flowing to the first light emitting element 5 and the second light emitting element 6, it is possible to adjust the color by changing the ratio of the amount of light emitted by the two elements.

<Fourth Embodiment>
In the first to third embodiments, the sapphire-based first light emitting element 5 and the silicon-based second light emitting element 6, which are two types of light emitting elements having different light distribution characteristics, are used. ), (B), and (c), two sapphire-based second light emitting elements 6 and 6 having the same light distribution characteristics are mounted on the substrate 10, and one (right side in the figure) second light emitting element 6 is mounted. By disposing the light shielding plate 11 on the outer periphery of the substrate 10 for shielding the light emitted from the circumferential direction of the second light emitting element 6, the light distribution characteristic with the other (left side in the figure) the first light emitting element 5 is provided. The second light emitting element 6 that is different (specifically, the angular distribution of light is narrower than that of the first light emitting element 5 on the left side) is configured. The light-shielding plate 11 has an upper end that is slightly higher than the irradiation surface 6A of the second light-emitting element 6, and is formed of an annular member that extends in the circumferential direction. By changing the height of the light shield plate 11, the angular distribution of light can be adjusted.

  The present invention is not limited to the above-mentioned embodiment, and various modifications can be made without departing from the gist of the present invention.

  In the above embodiment, the light emitting diode 1 is composed of two types of light emitting elements 5 and 6 having different light distribution characteristics, but the light emitting diode may be composed of three or more types of light emitting elements having different light distribution characteristics. The light characteristic is composed of two kinds of light emitting elements, and may be composed of a combination of three or more of them.

  Further, although the light distribution characteristics of the light emitting elements 5 and 6 themselves are used in the above-described embodiment, the light shielding plate 11 shown in FIGS. 7A, 7B, and 7C is used, and in addition, a light shielding element is used. The light distribution characteristics may be changed by blocking a part of the light emitted from the light emitting elements 5 and 6 by applying a paint to the base.

  Further, in the above embodiment, the light emitting diode 1 is shown as the light emitting device, but it may be a laser diode (LD).

  Further, in the above-described embodiment, the light emitting device that emits white light is configured, but a light emitting device that emits primary colors such as green, yellow, and red may be configured, or a color other than the primary colors, for example, pastel color (intermediate color). You may comprise the light-emitting device which light-emits. For example, FIG. 8 shows an emission spectrum in the case where the light emitted from the two light emitting elements 5 and 6 is converted by the phosphor and the converted light is a pastel color (intermediate color). The emission spectrum shown by the solid line is from the first light emitting element 5, and the emission spectrum shown by the dotted line is from the second light emitting element 6. Since there is a clear difference in the spectral shape between the first light emitting element 5 and the second light emitting element 6 in the wavelength band near 450 nm, it is possible to make a difference in hue even with colors such as pastel colors (intermediate colors). I understand.

  DESCRIPTION OF SYMBOLS 1 ... Light emitting diode, 2 ... Recess, 3 ... Package, 4 ... Bottom surface (upper surface), 4A ... Partial upper surface, 5 ... 1st light emitting element, 5A ... Irradiation surface, 6 ... 2nd light emitting element, 6A ... Irradiation surface, 7 ... Sealing resin, 7A ... Surface, 8 ... Bonding wire, 9 ... Peripheral side wall, 10 ... Substrate (flat plate member), 11 ... Shading plate, H1, H2 ... Distance

Claims (2)

Light emission wavelengths in the visible light range are output, and a plurality of types of light emitting elements with different light distribution characteristics that are the angular distribution of light are sealed, and the light emitting elements are sealed and excited by the light emitted from the light emitting elements. And the same sealing resin made of a light-transmitting material containing a single-color or multiple-color phosphor for emitting light of a color different from the emission color of the light-emitting element ,
The plurality of types of light emitting elements include a first light emitting element having a wide light angle distribution and a second light emitting element having a narrow light angle distribution, from the surface of the sealing resin to the irradiation surface of the second light emitting element. Is shorter than the distance from the surface of the sealing resin to the irradiation surface of the first light emitting element .   The emission wavelength has a peak wavelength in the range of 380 nm to 470 nm, and the phosphor is composed of a phosphor that converts light emitted from the light emitting element into white light. 1. The light emitting device according to 1.

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