INTEGRATED LED-BASED LUMINARE FOR GENERAL LIGHTING

• US 20100207534A1
• Filed: 10/08/2008
• Published: 08/19/2010
• Est. Priority Date: 10/09/2007
• Status: Active Grant

• Current Assignee: Signify Holding B.V. (Signify N.V.)
• Original Assignee: Philips Solid State Lighting Solutions Inc (Signify N.V.)
• Inventors: Roberts, Ron, Datta, Michael, Williamson, Ryan C., Lys, Ihor A., Roberge, Brian, Mollnow, Tomas, Dowling, Kevin J., Morgan, Frederick M.
• Granted Patent: US 8,390,207 B2
• Time in Patent Office: Days
• US Class Current: 315/186
• CPC Class Codes: F21K 9/60 Optical arrangements integrated in the light source, e.g. for improving the colour rendering index or the light extraction
• CPC Class Codes: H01L 2224/48091 Arched
• CPC Class Codes: H01L 2224/48227 connecting the wire to a bond pad of the item
• CPC Class Codes: H01L 2924/00014 the subject-matter covered by the group, the symbol of which is combined with the symbol of this group, being disclosed without further technical details
• CPC Class Codes: H05B 45/28 using temperature feedback
• CPC Class Codes: H05B 45/3725 Switched mode power supply [SMPS]
• CPC Class Codes: H05B 45/375 using buck topology
• CPC Class Codes: Y02B 20/30 Semiconductor lamps, e.g. solid state lamps [SSL] light emitting diodes [LED] or organic LED [OLED]

Abstract

Lighting apparatus and methods employing LED light sources are described. The LED light sources are integrated with other components in the form of a luminaire or other general purpose lighting structure. Some of the lighting structures are formed as Parabolic Aluminum Reflector (PAR) luminaires, allowing them to be inserted into conventional sockets. The lighting structures display beneficial operating characteristics, such as efficient operation, high thermal dissipation, high output, and good color mixing.

Claims

1. An illumination apparatus (100), comprising:

an LED-based light source (150);

an optic coupled to the LED-based light source (160);

a heat sink (130) coupled to the LED-based light source;

a base (110) for mechanically and electrically engaging with a socket; and

a housing (400) comprising an electrically non-conducting material and mechanically coupled to the base, wherein the LED-based light source, the optic, and the heat sink are disposed within the housing.

2. The apparatus of claim 1, wherein the LED-based light source comprises at least one first LED for generating first radiation having a first spectrum and at least one second LED for generating second radiation having a second spectrum different from the first spectrum.

3. The apparatus of claim 2, wherein the at least one first LED and the at least one second LED are electrically connected in series between a first node and a second node, wherein a series current flows between the first node and the second node when an operating voltage is applied across the first node and the second node, and wherein the apparatus comprises:

a temperature sensor disposed proximate to the LED-based light source for generating a temperature signal; and

a switching power supply for providing power factor correction and the operating voltage, the switching power supply receiving the temperature signal and controlling at least one controllable current path connected in parallel with one of the at least one first LED and the at least one second LED so as to at least partially divert the series current around the one of the at least one first LED and the at least one second LED in response to the temperature signal, such that a first current through the at least one first LED and a second current through the at least one second LED are different.

4. The apparatus of claim 1, wherein the housing comprises plastic and defines a plurality of holes configured to facilitate air flow through the housing.

5. The apparatus of claim 4, wherein the plurality of holes each has an axis of symmetry oriented so as not to intersect electrical components of the apparatus.

6. The apparatus of claim 4, wherein at least one of the plurality of holes is less than or equal to approximately 2 mm in size.

7. The apparatus of claim 1, wherein the housing is made of glass.

8. The apparatus of claim 1, further comprising a cover lens connected to the housing, wherein the cover lens and housing in combination substantially surround the LED-based light source, the optic, and the heat sink.

9. The apparatus of claim 1, wherein the optic has an exit aperture through which light from the LED-based light source passes, and wherein the apparatus further comprises a diffuser disposed within the housing across the exit aperture.

10. The apparatus of claim 1, wherein the base is an Edison-type screw base.

11. An illumination apparatus comprising:

an LED-based light source (150) comprising a first die (202) and a second die (204) coupled to a substrate (206), the first die configured to produce a first spectrum of radiation (503) and the second die configured to produce a second spectrum of radiation (505), the LED-based light source further comprising a primary optic (203) having first texturing (205, 207) on at least a portion thereof; and

a secondary optic (160) coupled to the LED-based light source (150) and configured to collimate light produced by the LED-based light source (150), wherein the secondary optic has second texturing (167) on at least a portion of a light receiving surface of the secondary optic.

12. The apparatus of claim 11, wherein the primary optic comprises a hemispherical lens (203) raised a distance (H₁) above the substrate (206).

13. The apparatus of claim 11, wherein the secondary optic forms an exit aperture through which light produced by the LED-based light source passes, and wherein there is no diffusing element across the exit aperture.

14. The apparatus of claim 11, further comprising a heat sink to which the LED-based light source is thermally coupled, and a thermal connector mounted in or on the heat sink.

15. The apparatus of claim 14, further comprising an element mechanically coupled to the heat sink and having a cavity therein for receiving power circuitry for providing power to the LED-based light source, the element configured to mate to a screw base.

16. The apparatus of claim 15, further comprising the power circuitry, and a flexible circuit interconnecting the LED-based light source and the power circuitry.

17. The apparatus of claim 15, further comprising a housing formed of electrically non-conducting material, and wherein the LED-based light source, the secondary optic, and the heat sink are disposed within the element.

18. The apparatus of claim 17, wherein the housing defines one or more holes configured to facilitate heat dissipation.

19. The apparatus of claim 18, further comprising a cover lens coupled to the housing, wherein the cover lens and housing in combination substantially surround the LED-based light source, the secondary optic, and the heat sink.

20. The apparatus of claim 14, wherein the thermal connector is a copper plug.

21. The apparatus of claim 20, wherein the copper plug has a first surface raised above the heat sink, and wherein the LED-based light source is mounted on the first surface of the copper plug.

22. The apparatus of claim 21, wherein the apparatus further comprises a temperature sensor mounted within or proximate to the heat sink and thermally coupled to the LED-based light source.

23. The apparatus of claim 11, wherein the secondary optic has an exit aperture, and wherein the apparatus further comprises a diffuser disposed across the exit aperture.

24. The apparatus of claim 11, further comprising a ceramic mount to which the LED-based light source is mounted, and further comprising a flexible circuit to which the LED-based light source is wire-bonded to form an electrical interconnection.

25. A lighting apparatus configured in a Parabolic Aluminum Reflector (PAR) 38 form factor, the apparatus comprising:

at least one first LED (202) for generating first radiation (503) having a first spectrum;

at least one second LED (204) for generating second radiation (505) having a second spectrum different from the first spectrum, wherein essentially white light generated by the apparatus includes a mixture of the first radiation and the second radiation;

a switching power supply (414) for providing power factor correction, an operating voltage (516) for the at least one first LED and the at least one second LED, a first current (552) for the at least one first LED, and a second current (554) for the at least one second LED;

a base (110) for mechanically and electrically engaging with a socket; and

a housing (400) made of an electrically non-conducting material, mechanically coupled to the base and configured in the PAR38 form factor, wherein the at least one first LED, the at least one second LED, and the switching power supply are disposed within the housing,

wherein the switching power supply is configured to control the first current and the second current such that the essentially white light generated by the apparatus has a color temperature in the range from approximately 2600K to 3000K, and an output of at least about 700 lumens at 10 Watts.

26. The apparatus of claim 25, wherein at least one of a first number of the at least one first LED, a second number of the at least one second LED, the first current, and the second current are selected such that the essentially white light generated by the apparatus provides a color rendering index (CRI) of at least 90.

27. The apparatus of claim 25, further comprising a collimating optic disposed to receive the first radiation and the second radiation.

28. The apparatus of claim 27, wherein at least one of an arrangement of the at least one first LED and the at least one second LED, and the collimating optic is configured to provide a full-width half-maximum beam angle of approximately 25 degrees for the essentially white light generated by the apparatus.