Solid state lighting apparatuses with non-uniformly spaced emitters for improved heat distribution, system having the same, and methods having the same

• US 10,267,506 B2
• Filed: 12/07/2015
• Issued: 04/23/2019
• Est. Priority Date: 11/22/2010
• Status: Active Grant

• Current Assignee: Creeled Incorporated
• Original Assignee: CREE Incorporated (Wolfspeed, Inc.)
• Inventors: Tudorica, Florin A., Hussell, Christopher P.
• Primary Examiner(s): Truong, Bao Q
• Assistant Examiner(s): Horikoshi, Steven Y
• Application Number:
  US14/961,470
• Publication Number:
  US 20160161098A1
• Time in Patent Office: 1,233 Days
• CPC Class Codes: F21V 29/10 Arrangement of heat-generating components to reduce thermal damage, e.g. by distancing heat-generating components from other components to be protected
• CPC Class Codes: F21Y 2105/12 characterised by the geometrical disposition of the light-generating elements, e.g. arranging light-generating elements in differing patterns or densities
• CPC Class Codes: F21Y 2115/10 Light-emitting diodes [LED]
• CPC Class Codes: H01L 2224/45099 Material
• CPC Class Codes: H01L 2224/48137 the bodies being arranged next to each other, e.g. on a common substrate
• CPC Class Codes: H01L 25/0753 the devices being arranged next to each other
• CPC Class Codes: H01L 27/156 two-dimensional arrays
• CPC Class Codes: H01L 2924/00 Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
• 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: H01L 2924/0002 Not covered by any one of groups H01L24/00, H01L24/00 and H01L2224/00
• CPC Class Codes: H01L 33/505 characterised by the shape, e.g. plate or foil
• CPC Class Codes: H01L 33/60 Reflective elements
• CPC Class Codes: H01L 33/62 Arrangements for conducting electric current to or from the semiconductor body, e.g. lead-frames, wire-bonds or solder balls
• CPC Class Codes: H05B 45/56 involving measures to prevent abnormal temperature of the LEDs

Abstract

Solid state lighting apparatuses, systems, and related methods for improved heat distribution are described. A solid state lighting apparatus can include a substrate and an array of solid state light emitters of varying power arranged on or over the substrate, wherein a predetermined group of the solid state light emitters includes solid state light emitters non-uniformly spaced apart from one another. A method of providing a solid stare lighting apparatus can include providing a substrate, and mounting an array of solid state light emitters of varying power on or over the substrate such that a predetermined group of the solid state light emitters includes solid state light emitters non-uniformly spaced apart from one another.

Claims

1. A solid state lighting apparatus, comprising:

a substrate;

solid state light emitters arranged on or over the substrate, the solid state light emitters being arranged in strings of light emitters;

a plurality of driving components arranged on or over the substrate, each driving component being configured to control at least two strings of light emitters,

wherein the strings of light emitters are arranged in an array of solid state light emitters,

wherein a first string of the at least two strings of light emitters for each driving component is configured to consume more total power and more power per solid state light emitter than a second string of the at least two strings of light emitters for each driving component,

wherein each driving component is configured to independently activate and deactivate the first string associated therewith during a portion of an alternating current (AC) cycle, such that each first string is not activated during a same portion of the AC cycle as any other first string, and

wherein the solid state light emitters of each first string are non-uniformly spaced apart from each other.

2. The solid state lighting apparatus of claim 1, wherein each of the plurality of driving components is configured to independently activate the first string less than the second string, such that each solid state light emitter in the first string operates less than, or emits less light than, solid state light emitters in the second string.

3. The solid state lighting apparatus of claim 2, wherein the first string associated with each driving component is disposed in, around, or extending towards a center of a light emission area disposed over the substrate.

4. The solid state lighting apparatus of claim 2, wherein the first string associated with each driving component is disposed around a periphery of a light emission area disposed over the substrate.

5. The solid state lighting apparatus of claim 1, comprising a light emission area, which is disposed over the substrate and comprises the array of solid state light emitters, wherein a central portion of the light emission area has a lower die density than a peripheral portion of the light emission area.

6. The solid state lighting apparatus of claim 5, wherein the array of solid state light emitters is spaced apart such that each solid state light emitter disposed around or near the central portion of the light emission area has a non-uniform spacing compared to other solid state light emitters in the array.

7. The solid state lighting apparatus of claim 6, wherein each solid state light emitter disposed around or near the central portion of the light emission area is spaced apart from another solid state light emitter disposed around or near the central portion of the light emission area by between approximately 200 μ

m and 400 μ

m.

8. The solid state lighting apparatus of claim 5, wherein the solid state light emitters are spaced apart such that at least a portion of the central portion of the light emission area is devoid of solid state light emitters.

9. The solid state lighting apparatus of claim 5, wherein the solid state light emitters are spaced apart such that, relative to a width of the central portion of the light emission area, at least one row of solid state light emitters has a non-uniform spacing compared to other solid state light emitters in the array.

10. The solid state lighting apparatus of claim 5, wherein one or more first string is disposed proximate to the peripheral portion of the light emission area, solid state light emitters in the one or more first string being configured to generate more heat than solid state light emitters in the second strings.

11. The solid state lighting apparatus of claim 1, wherein one or more first string is configured such that the solid state light emitters thereof are spaced further apart than solid state light emitters in the second string.

12. The solid state lighting apparatus of claim 1, comprising a phosphoric filling material disposed over the solid state light emitters, wherein a layer of phosphor within the filling material settles to, or is otherwise proximate to, a bottom of the phosphoric filling material.

13. A method of providing a solid state lighting apparatus, the method comprising:

providing a substrate;

mounting solid state light emitters on or over the substrate to form strings of light emitters that are arranged in an array of solid state light emitters;

arranging a plurality of driving components on or over the substrate;

wherein each driving component controls at least two strings of light emitters;

wherein a first string of the at least two strings of light emitters for each driving component consumes more total power and more power per solid state light emitter than a second string of the at least two strings of light emitters for each driving component,

wherein each driving component independently activates and deactivates the first string associated therewith during a portion of an alternating current (AC) cycle, such that each first string is not activated during a same portion of the AC cycle as any other first string, and

wherein the solid state light emitters of the each first string are non-uniformly spaced apart from each other.

14. The method of claim 13, wherein each of the plurality of driving components independently activates the first string less than the second string, such that each solid state light emitter in the first string operates less than, or emits less light than, solid state light emitters in the second string.

15. The method of claim 14, comprising consuming, with at least one first string, a higher total power and power per solid state light emitter than the second strings, wherein the at least one first string is disposed in, around, or extending towards a center of a light emission area disposed over the substrate.

16. The method of claim 13, comprising defining a light emission area disposed over the substrate, wherein a central portion of the light emission area has a lower die density than a peripheral portion of the light emission area.

17. The method of claim 16, wherein mounting the solid state light emitters on or over the substrate comprises spacing the solid state light emitters apart, such that each solid state light emitter disposed around or near the central portion of the light emission area has a non-uniform spacing compared to other solid state light emitters in the array.

18. The method of claim 16, wherein mounting the solid state light emitters on or over the substrate comprises arranging one or more first string proximate to the peripheral portion of the light emission area, solid state light emitters in the one or more first string emitting more heat than solid state light emitters in the second strings.

19. A solid state lighting system, comprising:

a substrate;

solid state light emitters arranged on or over the substrate, wherein the solid state light emitters are arranged in strings of light emitters to form an array of solid state light emitters;

a plurality of driving components arranged on or over the substrate, each driving component being configured to control at least two strings of light emitters; and

a light emission area comprising the array of solid state light emitters, wherein the light emission area is disposed over the substrate, and wherein a central portion of the light emission area has a lower die density than a peripheral portion of the light emission area,

wherein a first string of the at least two strings of light emitters for each driving component are configured to consume more total power and more power per solid state light emitter than a second string of the at least two strings of light emitters for each driving component, and

wherein the plurality of driving components are each configured to independently activate and deactivate the first string associated therewith during a portion of an alternating current (AC) cycle, such that each first string is not activated during a same portion of the AC cycle as any other first string.

20. The solid state lighting system of claim 19, wherein the solid state light emitters are spaced apart from each other such that each solid state light emitter disposed around or near the central portion of the light emission area has a non-uniform spacing compared to other solid state light emitters in the array.

21. The solid state lighting system of claim 19, wherein the solid state light emitters of each first string has a non-uniform spacing from the solid state light emitters of each second string.