JP2011228356A - Light source unit - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a light source unit which can improve the color mixability while securing the heat dispersion efficiency.SOLUTION: A light source unit 1 has two LED devices 2 different in light color. Each LED device 2 has a substrate 3, and a light emitting part 4 which is formed on a mount face 30 of the substrate 3, and which emits light when brought into conduction. The substrate 3 has a main body part 31 provided with the light emitting part 4, and a heat sink part 32 extending from the main body part 31 along the mount face 30, and having an area equal to or larger than that of the light-emitting part 4 when viewed from a direction orthogonal to the mount face 30. The main body parts 31 of the substrates 3 abut on each other by the two LED devices 2. Thanks to the heat sink part 32, the heat dispersion efficiency can be secured, and the color mixability can be improved by making the distance between the light-emitting parts 4 smaller in comparison to the case where the main body parts 31 do not abut on each other.

Description

  The present invention relates to a light source device using light emitting diode elements of a plurality of colors.

  Conventionally, there has been provided a light source device that uses light emitting diode elements of a plurality of colors and obtains a desired light color by mixing these plurality of colors (for example, see Patent Document 1).

  Here, each light emitting diode element has a board | substrate and the light emission part which is formed on a board | substrate and is lighted and is light-emitted.

JP 2007-265818 A

  In the light source device as described above, as a method of improving the color mixing property, a method of providing a diffusing member that covers each light emitting unit and diffuses light of each light emitting unit, and a method of reducing a distance between the light emitting units You could think so.

  However, when a diffusing member is used, loss increases due to absorption of light in the diffusing member or reflection of light to the inside of the light emitting portion, and as a result, the efficiency decreases by 5% to 20%. End up.

  On the other hand, if the method is to reduce the distance between the light emitting portions, the color mixing property can be improved without causing the increase in loss as described above.

  However, if the area of the substrate of each light-emitting diode element is reduced to about the area of the light-emitting part in order to enable the arrangement to reduce the distance between the light-emitting parts, the heat dissipation is reduced due to the reduction of the heat capacity of the substrate. .

  The present invention has been made in view of the above-described reasons, and an object of the present invention is to provide a light source device that can improve color mixing while ensuring heat dissipation.

  The light source device of the present invention is a light source device including a plurality of light emitting diode elements each including at least two light emitting diode elements having different light colors, and each of the light emitting diode elements includes a substrate and a mounting of the substrate. A light emitting portion that is formed on a surface and emits light when energized, and in each of the light emitting diode elements, the substrate includes a main body portion on which the light emitting portion is provided, and the mounting surface. A heat sink portion extending from the main body portion and having an area equal to or larger than the light emitting portion when viewed from a direction orthogonal to the mounting surface, and for each of the light emitting diode elements, the main body portion includes all other The light emitting diode element is in contact with the main body of each light emitting diode element.

  The light source device preferably includes a lens that covers the light emitting portions of all the light emitting diode elements and distributes the light of each light emitting diode element.

  Furthermore, the lens preferably includes a substrate made of a light-transmitting material and fine particles made of a material having a higher thermal conductivity than the substrate and dispersed in the substrate.

  According to the present invention, heat dissipation can be ensured by the heat sink portion, and the color mixing property can be improved by reducing the distance between the light emitting portions as compared with the case where the main body portions are not brought into contact with each other.

It is a perspective view which shows embodiment of this invention. It is a perspective view which shows the light emitting diode element in the same as the above. It is a perspective view which shows the light emitting diode element in the example of a change same as the above. It is a perspective view which shows the light source device comprised by the light emitting diode element of FIG. It is a perspective view which shows the light emitting diode element in another modified example same as the above. It is a top view which shows the light source device comprised by the light emitting diode element of FIG. It is a perspective view which shows the light emitting diode element in another modified example same as the above. It is a perspective view which shows the light emitting diode element in another modified example same as the above. It is a perspective view which shows the light emitting diode element in another modified example same as the above. It is a perspective view which shows another example of a change same as the above. It is a perspective view which shows another example of a change same as the above. It is a top view which shows another example of a change same as the above.

  The best mode for carrying out the present invention will be described below with reference to the drawings.

  As shown in FIG. 1, the light source device 1 of the present embodiment includes two light emitting diode elements 2 having different light colors.

  As shown in FIG. 2, each light-emitting diode element 2 has a rectangular flat plate substrate 3 and one surface in the thickness direction of the substrate 3 (upper surface in the figure; hereinafter referred to as “mounting surface”) 30. And a light emitting unit 4 that emits light when energized. The light emitting unit 4 includes a light emitting layer 41 that generates light when energized, and a phosphor layer 42 that covers the light emitting layer 41 and converts the light color of the light emitting layer 41. Each of the light emitting diode elements 2 is made of a conductive material such as metal and is electrically connected to the light emitting layer 41 and held on the substrate 3 so as to protrude from one end in the longitudinal direction of the substrate 3. Two power supply terminals 5 are provided. The electrical connection between the power supply terminal 5 and the light emitting layer 41 may be achieved through a conductive pattern (not shown) provided on the substrate 3 or may be achieved by wire bonding.

  As the material of the substrate 3, it is desirable to use a material having high thermal conductivity. For example, alumina, aluminum nitride, or a thermosetting resin containing an alumina filler can be used. In general, since a metal material has a higher thermal conductivity than an insulating material, an insulating layer (not shown) made of an insulating material such as aluminum nitride is formed on a metal plate (not shown) such as a copper plate. A substrate 3 in which metal materials are appropriately combined, such as a substrate 3 on which the light emitting portion 4 is formed on the insulating layer and a substrate 3 having a structure in which a metal material is embedded in an insulating material, is provided. If used, the heat dissipation can be improved as compared with the case where the substrate 3 made of only an insulating material is used. Since all of the various substrates 3 as described above can be realized by a well-known technique, detailed illustration and description are omitted. The dimensions of the substrate 3 are, for example, a total length in the longitudinal direction of 5.0 mm, a total length in the short direction of 2.4 mm, and a thickness dimension of 0.8 mm.

  Examples of the material of the phosphor layer 42 include a CSO phosphor that converts green light, a YAG phosphor that converts yellow light, a SCASN phosphor that converts red light, and a deep red color. For example, a CASN phosphor that converts light into light can be used. When the light emitting layer 41 is made of, for example, GaN and generates blue light or ultraviolet light, for example, a daylight color having a color temperature exceeding 7000K, a color can be obtained by using various phosphors as described above in an appropriate combination and ratio. Colors such as daylight white at a temperature of about 5000K, white at a color temperature of about 4200K, and a light bulb color at a color temperature of 3200K or less can be realized.

  In addition, when the light emitting diode element 2 that directly emits the light of the light emitting layer 41 without using the phosphor as described above and the light emitting diode element 2 having the phosphor layer 42 in the light emitting portion 4 are mixed, these light emitting diodes are used. In order to make the light distribution characteristics uniform between the elements 2, also in the light emitting diode element 2 that emits the light of the light emitting layer 41 as it is, a diffusion layer (not shown) that diffuses the light of the light emitting layer 41 to the same extent as the phosphor layer 42. ) Is preferably provided in place of the phosphor layer 42. The diffusion layer as described above can be constituted, for example, by dispersing spherical silica having an average particle diameter of several μm in a substrate through which light from the light emitting layer 41 passes.

  Here, the light emitting unit 4 is formed at one end in the short direction of the mounting surface 30 of the substrate 3 and at the center in the longitudinal direction. When viewed from the thickness direction of the substrate 3, each side of the light emitting unit 4 is a substrate. It is a square shape parallel to the three sides.

  Furthermore, the distance between the other end in the short direction of the mounting surface 30 of the substrate 3 and the light emitting unit 4 and the distance between the both ends in the longitudinal direction of the mounting surface 30 of the substrate 3 and the light emitting unit 4 are respectively (That is, the length of one side of the square shape). That is, the portion of the substrate 3 that overlaps the light-emitting portion 4 when viewed from the thickness direction and the vicinity thereof are the main body portion 31, and the U-shaped portion other than the main body portion 31 is the heat sink portion 32. The main body 31 is not only a part that completely overlaps the light emitting unit 4 when viewed from the thickness direction of the substrate 3, but is a region between the end of the mounting surface 30 and the light emitting unit 4 and the existing light emitting unit 4. It also includes a portion that overlaps an area that is so narrow that a light emitting portion having the same size and shape cannot be arranged.

  The two light emitting diode elements 2 are integrated with each other by bringing the main body portions 31 into contact with each other while the mounting surfaces 30 are positioned in the same plane with the mounting surfaces 30 facing in the same direction. Yes. When the two light emitting diode elements 2 are integrated as described above, the two light emitting portions 4 and the main body portion 31 are surrounded by the heat sink portion 32 when viewed from the thickness direction of the substrate 3. The above integration is performed by bonding the substrates 3 to each other with an adhesive, for example. Since the light emitting section 4 generates heat during light emission, it is desirable to use a highly heat-resistant material such as an inorganic adhesive or a silicone resin as the adhesive.

  In the light source device 1 in which the light emitting diode elements 2 having different light color temperatures of the light emitting units 4 are integrated, a color temperature intermediate between the light color temperatures of the individual light emitting units 4 is realized by color mixing. Can do. Further, by appropriately adjusting the ratio of the light output between the light emitting units 4 by adjusting the input current to each light emitting unit 4, the overall color temperature is changed from the color temperature of one light emitting unit 4 to the other light emitting unit 4. It is also possible to adjust within the range up to the color temperature.

  According to the above configuration, for example, the distance between the light emitting units 4 as compared with the case where the main body portions 31 are not brought into contact with each other as in the case where the heat sink portions 32 are provided over the entire circumference of the main body portion 31 in each light emitting diode element 2. Can be reduced to reduce light unevenness. Moreover, heat dissipation can be improved compared with the case where the heat sink part 32 is not provided.

  Here, the shape of the substrate 3 and the arrangement of the power supply terminals 5 are not limited to the above. For example, the heat sink portion 32 may be provided only on one side of the main body portion 31 as shown in FIG. The dimensions of the substrate 3 in the example of FIG. 3 are, for example, a total length in the longitudinal direction of 2.4 mm, a total length in the short direction of 1.3 mm, and a thickness dimension of 0.8 mm. In the example of FIG. 3, each power supply terminal 5 protrudes from the end surface opposite to the main body 31 in the heat sink 32. In this case, as shown in FIG. 4, the two light emitting diode elements 2 are integrated in such a manner that the opposite end surfaces of the main body 31 with respect to the heat sink 32 are brought into contact with each other. If the above configuration is adopted, the area of each substrate 3 in the example of FIGS. 1 and 3 is 6 times or more than the area of the light emitting section 4, whereas each of the substrates 3 in the example of FIGS. Since the area is about twice as large as that of the light emitting unit 4, the heat capacity of the heat sink unit 32 is lower than that of the example of FIGS. 1 and 2, but the manufacturing cost can be reduced by reducing the material cost, and the size can be reduced. Can be realized.

  Furthermore, if the light source device 1 is composed of three light emitting diode elements 2 and the light color of each light emitting unit 4 is one of the three primary colors of light such as red, blue and green, the light output of each light emitting unit 4 Various light colors can be realized by adjusting this. The blue light can be realized by, for example, the light emitting layer 41 that generates blue light, the light emitting layer 41 that generates ultraviolet light, and the phosphor layer 42 made of a BAM phosphor that converts ultraviolet light into blue light. It can also be realized by a combination of the above. When three light emitting diode elements 2 are used as described above, one light emitting diode element 2 is added to the example of FIG. 4, and the main body portion 31 is the end face of the light emitting diode element 2 in the longitudinal direction of the substrate 3. The end face on the side may be brought into contact with the main body 31 of the substrate 3 of the other two light-emitting diode elements 2 to form a T shape as a whole, but the configuration shown in FIGS. May be adopted. In the example of FIGS. 5 and 6, in each light emitting diode element 2, the end surface in the longitudinal direction of the substrate 3 and the end surface on the main body portion 31 side is a plane orthogonal to the mounting surface 30 and 120 ° to each other. It is set as the convex shape comprised by the two contact surfaces 31a which make | form the corner | angular. In the example of FIG. 5, the dimensions of the substrate 3 are, for example, the total length in the left-right direction in FIG. 3 is 2.8 mm, the total length in the vertical direction in FIG. 3 is 1.3 mm, and the thickness dimension is 0. .8 mm. The three light-emitting diode elements 2 are arranged such that the mounting surfaces 30 are positioned on the same plane in the same direction, and the respective contact surfaces 31a are in contact with the other light-emitting diode elements 2 respectively. The surface 31a is brought into contact with and integrated with the surface 31a. In the light emitting unit 4, when viewed from the thickness direction of the substrate 3, one diagonal line is parallel to the longitudinal direction of the substrate 3 (that is, the direction in which the main body portion 31 and the heat sink portion 32 are arranged), and one corner is the substrate 3. It is located in the vicinity of the corner between the contact surfaces 31a. If the three light emitting diode elements 2 having a common structure as shown in FIGS. 5 and 6 are arranged rotationally symmetrical three times, the heat radiation condition of the light emitting section 4 can be changed between the three light emitting diode elements 2. Can be aligned. In the case where three light emitting diode elements 2 are provided as described above, the light colors of the light emitting section 4 are shared by the two light emitting diode elements 2, and the light of the light emitting section 4 is shared by only one remaining light emitting diode element 2. The color may be different from that of the other two light emitting diode elements 2.

  Further, as shown in FIGS. 7 to 9, each light emitting unit 4 is provided with a plurality of light emitting layers 41 separated from each other, and the plurality of light emitting layers 41 are connected in series between the power supply terminals 5. May be. If this configuration is adopted, the loss due to the current flowing in the direction not contributing to light emission in the light emitting layer 41 (for example, the direction along the mounting surface 30) is suppressed as compared with the case where the light emitting layer 41 is formed continuously and integrally. be able to.

  Moreover, as shown in FIGS. 10-12, you may provide the lens 6 which covers each light emission part 4, respectively, and distributes the light radiated | emitted from each light emission part 4 suitably. Specifically, the lens 6 is a spherical lens, for example. The material of the lens 6 is a surface layer portion of the light-emitting portion 4 (a phosphor layer 42 when the light-emitting portion 4 has a phosphor layer 42, and a diffusion layer when the light-emitting portion 4 has a diffusion layer. 4 is composed of the light emitting layer 41 alone, it is desirable to use a material having a refractive index intermediate between the refractive index of the light emitting layer 41) and the refractive index of the substance (for example, air) around the light source device 1, thereby The taking-out efficiency can be improved. The lens 6 as described above can be provided by, for example, a mold. The present inventor first attaches a hemispherical silicone resin outer shell (not shown) having a thickness of about 0.5 mm so as to cover each light emitting portion 4 and then fills the outer shell with the silicone resin. Then, the lens 6 was formed, and the luminous flux was successfully improved by 10% compared to before the lens 6 was formed.

  Further, the lens 6 may be composed of a substrate made of a material that transmits the light of each light emitting section 4 and fine particles dispersed in the substrate made of a material having a higher thermal conductivity than the material of the substrate. Good. By adopting this configuration, the heat conductivity is improved by improving the thermal conductivity of the lens 6 as compared with the case where the lens 6 is configured only by the substrate. When the spherical alumina having an average particle diameter of about 0.8 μm is dispersed in the substrate by about 2 wt% as the fine particles in the lens 6, the inventor does not disperse the fine particles as described above. It was confirmed that the temperature at the apex of the lens 6 was lowered by about 5 ° C. as compared with the case where only the substrate was used. Further, when the fine particles are made of a material that reflects the light of each light emitting portion 4 such as alumina, the light of each light emitting portion 4 is diffused by the reflection of the fine particles, thereby further improving color mixing. Improved.

DESCRIPTION OF SYMBOLS 1 Light source device 2 Light emitting diode element 3 Board | substrate 4 Light emission part 6 Lens 30 Mounting surface 31 Main-body part 32 Heat sink part

Claims (3)

A light source device comprising a plurality of light emitting diode elements each including at least two light emitting diode elements each having a different light color,
Each of the light emitting diode elements has a substrate and a light emitting portion that is formed on the mounting surface of the substrate and emits light when energized,
In each of the light emitting diode elements, the substrate includes a main body provided with the light emitting unit, and the light emitting unit as viewed from a direction perpendicular to the mounting surface and extending from the main body along the mounting surface. A heat sink portion having the above area,
For each of the light emitting diode elements, the light source device is characterized in that the main body is in contact with the main body of each of the other light emitting diode elements.   The light source device according to claim 1, further comprising a lens that covers the light emitting portions of all the light emitting diode elements and distributes the light of each light emitting diode element.   3. The light source device according to claim 2, wherein the lens has a substrate made of a light-transmitting material and fine particles made of a material having a higher thermal conductivity than the substrate and dispersed in the substrate. .

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