Light Emitting Device and Luminaire

• US 20140153238A1
• Filed: 08/30/2013
• Published: 06/05/2014
• Est. Priority Date: 12/04/2012
• Status: Active Grant

• Current Assignee: Toshiba Lighting & Technology Corporation (Toshiba Corporation)
• Original Assignee: Toshiba Lighting & Technology Corporation (Toshiba Corporation)
• Inventors: Nishimura, Kiyoshi, Betsuda, Nobuhiko, Watanabe, Miho, Tanaka, Hirotaka, Honma, Takuya, Okawa, Hideki, Shimokawa, Kazuo, Sasaki, Akihiro, Matsumoto, Katsuhisa
• Granted Patent: US 9,236,551 B2
• Time in Patent Office: Days
• US Class Current: 362/237
• CPC Class Codes: F21Y 2115/10 Light-emitting diodes [LED]
• CPC Class Codes: H01L 2224/16225 the item being non-metallic, e.g. insulating substrate with or without metallisation
• CPC Class Codes: H01L 25/0753 the devices being arranged next to each other
• CPC Class Codes: H01L 33/505 characterised by the shape, e.g. plate or foil
• CPC Class Codes: H01L 33/642 characterized by the shape
• CPC Class Codes: H01L 33/644 in intimate contact or integrated with parts of the device other than the semiconductor body
• CPC Class Codes: H05K 1/0209 External configuration of printed circuit board adapted for heat dissipation, e.g. lay-out of conductors, coatings
• CPC Class Codes: H05K 1/0306 Inorganic insulating substrates, e.g. ceramic, glass
• CPC Class Codes: H05K 2201/0305 Solder used for other purposes than connections between PCB or components, e.g. for filling vias or for programmable patterns
• CPC Class Codes: H05K 2201/10106 Light emitting diode [LED]
• CPC Class Codes: H05K 3/0061 onto a metallic substrate, e.g. a heat sink heat sinks for electric apparatus H05K7/20
• CPC Class Codes: H05K 3/284 for encapsulating mounted components H05K1/185 takes precedence

Abstract

According to one embodiment, there is provided a light-emitting device including a light-emitting section, a thermal radiation member, and a heat conduction layer. The light-emitting section includes a mounting substrate section and a light-emitting element section. The mounting substrate section includes a substrate, a first metal layer, and a second metal layer. The substrate includes a first principal plane including a mounting region and a second principal plane. The first metal layer includes mounting patterns provided in the mounting region. The light-emitting element section includes semiconductor light-emitting elements and a wavelength conversion layer. The semiconductor light-emitting elements are connected to the mounting patterns. The luminous exitance of the light-emitting element section is equal to or higher than 101 m/mm² and equal to or lower than 1001 m/mm². The thermal radiation member has an area equal to or larger than five times the area of the mounting region.

Claims

1. A light-emitting device comprising:

a light-emitting section including;

a mounting substrate section including;

an insulative substrate including a first principal plane including a mounting region and a second principal plane on an opposite side of the first principal plane;

a first metal layer provided on the first principal plane and including a plurality of mounting patterns provided in the mounting region; and

a second metal layer provided on the second principal plane and electrically insulated from the first metal layer, at least a part of the second metal layer overlapping the mounting region when projected on a first plane parallel to the first principal plane;

a light-emitting element section including;

a plurality of semiconductor light-emitting elements provided on the first principal plane, each of the plurality of semiconductor light-emitting elements being electrically connected to any one mounting pattern among the plurality of mounting patterns and another one mounting pattern adjacent to the mounting pattern among the plurality of mounting patterns; and

a wavelength conversion layer configured to cover at least parts of the plurality of semiconductor light-emitting elements, absorb at least a part of first light emitted from the plurality of semiconductor light-emitting elements, and emit second light having a wavelength different from a wavelength of the first light,

luminous exitance of light emitted from the light-emitting element section being equal to or higher than 101 m/mm² and equal to or lower than 1001 m/mm²;

a thermal radiation member opposed to the second principal plane and having an area equal to or larger than five times an area of the mounting region when projected on the first plane; and

a heat conduction layer provided between the thermal radiation member and the second metal layer.

2. The device according to claim 1, wherein

the first principal plane further includes a peripheral region provided around the mounting region, and

an area of the peripheral region is equal to or larger than four times the area of the mounting region.

3. The device according to claim 1, wherein a distance between an end of the first principal plane and the mounting region extending along a direction parallel to the first principal plane and passing a center of the mounting region is equal to or larger than ½

of width of the mounting region extending along the direction passing the center.

4. The device according to claim 1, wherein

the first metal layer further includes:

an electrode section for first connector connected to one of the plurality of mounting patterns; and

an electrode section for second connector connected to another one of the plurality of mounting patterns different from the one mounting pattern,

the light-emitting section further includes;

a first connector provided on the first principal plane and electrically connected to the electrode section for first connector; and

a second connector provided on the first principal plane and electrically connected to the electrode section for second connector, and

the light-emitting element section is arranged between the first connector and the second connector.

5. The device according to claim 1, wherein

the wavelength conversion layer includes:

a plurality of wavelength conversion particles configured to absorb at least a part of the first light and emit the second light; and

light transmissive resin in which the plurality of wavelength conversion particles are dispersed, and

Shore A of the light transmissive resin is equal to or higher than 15 and equal to or lower than 50.

6. The device according to claim 1, wherein

each of the plurality of semiconductor light-emitting elements includes:

a first semiconductor layer of a first conduction type including a first semiconductor portion and a second semiconductor portion arranged side by side with the first semiconductor portion in a direction crossing a superimposing direction extending from the thermal radiation member to the light-emitting section;

a second semiconductor layer of a second conduction type provided between the second semiconductor portion and the mounting substrate section; and

a light-emitting layer provided between the second semiconductor portion and the second semiconductor layer, and

the light-emitting element section further includes;

a first joining metal member provided between the first semiconductor portion and any one of the mounting patterns; and

a second joining metal member provided between the second semiconductor layer and another one of the mounting patterns.

7. The device according to claim 1, wherein an area of the second metal layer projected on the first plane is larger than 80% of the area of the mounting region.

8. The device according to claim 1, wherein an area of the second metal layer projected on the first plane is equal to or larger than 95% of an area of the second principal plane.

9. The device according to claim 1, wherein

a plurality of the light-emitting sections are provided, and

the heat conduction layer is arranged between the plurality of light-emitting sections and the thermal radiation member.

10. The device according to claim 1, further comprising a light reflective and insulative light reflecting resin layer, wherein

a plurality of the light-emitting sections are provided,

the substrate of one light-emitting section among the plurality of light-emitting sections includes a first side surface crossing the first principal plane,

the substrate of another light-emitting section arranged side by side with the one light-emitting section among the plurality of light-emitting sections in a surface parallel to the first principal plane includes a second side surface crossing the first principal plane and opposed to the first side surface, and

the light reflecting resin layer covers at least a part of the first side surface and covers at least a part of the second side surface.

11. The device according to claim 10, wherein thickness of the thermal radiation member is equal to or larger than 0.06 times and equal to or smaller than 0.12 times length in a direction parallel to the first principal plane of a region where the mounting substrate section is provided in the thermal radiation member.

12. The device according to claim 1, wherein a first surface of the thermal radiation member opposed to the second principal plane has irregularities.

13. The device according to claim 12, wherein a concave portion of the irregularities of the first surface includes a thermal radiation member bottom surface portion, a thermal radiation member side surface portion crossing the second principal plane, and a curved surface-shaped thermal radiation member corner portion that connects the thermal radiation member bottom surface portion and the thermal radiation member side surface portion.

14. The device according to claim 1, wherein a distance in a direction perpendicular to the first principal plane between an upper surface of any one of the plurality of semiconductor light-emitting elements and an upper surface of the wavelength conversion layer is equal to or larger than 100 micrometers and equal to or smaller than 300 micrometers.

15. A luminaire comprising:

a luminaire member; and

a light-emitting device provided on the luminaire member, wherein

the light-emitting device includes;

a light-emitting section including;

a mounting substrate section including;

an insulative substrate including a first principal plane including a mounting region and a second principal plane on an opposite side of the first principal plane;

a first metal layer provided on the first principal plane and including a plurality of mounting patterns provided in the mounting region; and

a second metal layer provided on the second principal plane and electrically insulated from the first metal layer, at least a part of the second metal layer overlapping the mounting region when projected on a first plane parallel to the first principal plane;

a light-emitting element section including;

a plurality of semiconductor light-emitting elements provided on the first principal plane, each of the plurality of semiconductor light-emitting elements being electrically connected to any one mounting pattern among the plurality of mounting patterns and another one mounting pattern adjacent to the mounting pattern among the plurality of mounting patterns; and

a wavelength conversion layer configured to cover at least parts of the plurality of semiconductor light-emitting elements, absorb at least a part of first light emitted from the plurality of semiconductor light-emitting elements, and emit second light having a wavelength different from a wavelength of the first light,

luminous exitance of light emitted from the light-emitting element section being equal to or higher than 101 m/mm² and equal to or lower than 1001 m/mm²;

a thermal radiation member opposed to the second principal plane and having an area equal to or larger than five times an area of the mounting region when projected on the first plane; and

a heat conduction layer provided between the thermal radiation member and the second metal layer, and

heat conductivity of the thermal radiation member is larger than heat conductivity of the luminaire member and equal to or higher than 300 W/(m·

K).

16. A light-emitting device comprising:

a ceramic substrate including a first surface and a second surface located on an opposite side of the first surface and including a pair of first end sides and a pair of second end sides orthogonal to the first end sides and having length equal to or smaller than length of the first end sides;

a first metal layer and a second metal layer formed on the first surface;

a third metal layer formed on the second surface;

a light-emitting section including a light-emitting element, one end of which is electrically connected to one end side of the first metal layer and the other end of which is electrically connected to one end side of the second metal layer;

a first connector provided on the other end side of the first metal layer;

a second connector provided on the other end side of the second metal layer; and

a thermal radiation plate made of metal connected to the third metal layer to be opposed to the ceramic substrate via a solder layer, wherein

when an axis passing a center of the ceramic substrate and extending along the first end side is represented as first axis and an axis passing the center of the ceramic substrate and extending along the second end side is represented as second axis, the light-emitting section is arranged such that a center of the light-emitting section substantially coincides with the center of the ceramic substrate, the center of the light-emitting section, the first connector, and the second connector are arranged on the first axis, and the first connector and the second connector are arranged to hold the light-emitting section therebetween.

17. The device according to claim 16 wherein the first connector and the second connector are provided to be substantially symmetrical to each other with respect to the second axis.

18. The device according to claim 16, wherein

the light-emitting section includes a cylindrical wall section, a plurality of light-emitting elements arranged in a cylinder of the wall section, an inter-element metal layer configured to electrically connect the plurality of light-emitting elements, and sealing resin filled in the cylinder of the wall section to cover the light-emitting elements, and

the light-emitting elements are provided to be symmetrical to one another with respect to the first axis and the second axis.