Bulb for light-emitting diode with modified inner cavity

• US 8,109,656 B1
• Filed: 02/04/2008
• Issued: 02/07/2012
• Est. Priority Date: 01/12/2007
• Status: Expired due to Fees

• Current Assignee: iLight Technologies Incorporated (Luminii, LLC)
• Original Assignee: iLight Technologies Incorporated (Luminii, LLC)
• Inventors: Hulse, George R.
• Primary Examiner(s): CARTER, WILLIAM JOSEPH
• Application Number:
  US12/025,293
• Time in Patent Office: 1,464 Days
• Field of Search: 362/293, 36231101-31104
• US Class Current: 362/293
• CPC Class Codes: C09K 11/06 containing organic luminescent materials
• CPC Class Codes: H01L 33/505 characterised by the shape, e.g. plate or foil
• CPC Class Codes: H01L 33/54 having a particular shape
• CPC Class Codes: H01L 33/58 Optical field-shaping elements
• CPC Class Codes: H05B 33/14 characterised by the chemical or physical composition or the arrangement of the electroluminescent material , or by the simultaneous addition of the electroluminescent material in or onto the light source

Abstract

A bulb adapted to fit over and around a light-emitting diode emitting a light of a first hue in a predetermined radiation pattern defines an inner cavity for housing the light-emitting diode with a cross-sectional geometry based on the predetermined radiation pattern of the light-emitting diode. The bulb is composed of a light-transmitting material and a light color-converting material, with the light color-converting material converting the light of the first hue into light of a desired hue, which is then viewed over a light-emitting surface of the bulb.

Claims

1. A bulb adapted to fit over and around a light-emitting diode emitting a light of a first hue in a predetermined radiation pattern, the bulb defining an inner cavity for housing the light-emitting diode having a cross-sectional geometry based on the predetermined radiation pattern of the light-emitting diode, and the bulb being composed of a light-transmitting material and a light color-converting material, said light color-converting material converting the light of the first hue into a light of a desired hue, which is then viewed over a light-emitting surface of the bulb, wherein, as a result of the cross-sectional geometry of the inner cavity defined by the bulb, at a point of maximum brightness in the predetermined radiation pattern of the light-emitting diode, the light of the first hue will pass through a greatest amount of said light color-converting material, while as brightness decreases in the predetermined radiation pattern of the light-emitting diode, the light of the first hue will pass through a lesser amount of said light color-converting material.

2. The bulb as recited in claim 1, wherein the bulb has a generally spherical shape.

3. The bulb as recited in claim 1, wherein the predetermined radiation pattern is a generally Lambertian radiation pattern.

4. The bulb as recited in claim 3, wherein the bulb has a generally spherical shape.

5. The bulb as recited in claim 1, wherein said light color-converting material is one or more fluorescent dyes.

6. The bulb as recited in claim 1, wherein said light color-converting material is one or more phosphorescent dyes.

7. The bulb as recited in claim 1, wherein said light color-converting material is a combination of fluorescent dyes and/or phosphorescent dyes.

8. The bulb as recited in claim 1, wherein said light-transmitting material is an acrylic resin.

9. The bulb as recited in claim 8, wherein said light color-converting material is one or more fluorescent dyes mixed into said acrylic resin.

10. The bulb as recited in claim 1, wherein the cross-sectional geometry for the inner cavity of the bulb is plotted by:

transposing the predetermined radiation pattern of the light-emitting diode onto an x-y coordinate system;

superimposing the bulb onto the x-y coordinate system, with the inner cavity of the bulb initially having a generally circular cross-section defining a boundary;

measuring a radial distance that the predetermined radiation pattern extends past the light-emitting surface of the bulb at selected angles on the x-y coordinate system; and

adding the measured radial distance at each selected angle to the generally circular cross-section of the inner cavity, extending the boundary of the inner cavity at each selected angle to plot the cross-sectional geometry for the inner cavity.

11. A lighting assembly, comprising

a light-emitting diode emitting a light of a first hue in a predetermined radiation pattern;

and

a bulb fitting over and around the light-emitting diode, the bulb defining an inner cavity for housing the light-emitting diode having a cross-sectional geometry based on the predetermined radiation pattern of the light-emitting diode, and the bulb being composed of a light-transmitting material and a light color-converting material, said light color-converting material converting the light of the first hue into a light of a desired hue, which is then viewed over a light-emitting surface of the bulb, wherein, as a result of the cross-sectional geometry of the inner cavity defined by the bulb, at a point of maximum brightness in the predetermined radiation pattern of the light-emitting diode, the light of the first hue will pass through a greatest amount of said light color-converting material, while as brightness decreases in the predetermined radiation pattern of the light-emitting diode, the light of the first hue will pass through a lesser amount of said light color-converting material.

12. The lighting assembly as recited in claim 11, wherein the bulb has a generally spherical shape.

13. The lighting assembly as recited in claim 11, wherein the predetermined radiation pattern is a generally Lambertian radiation pattern.

14. The lighting assembly as recited in claim 13, wherein the bulb has a generally spherical shape.

15. The lighting assembly as recited in claim 11, wherein said light color-converting material is one or more fluorescent dyes.

16. The lighting assembly as recited in claim 11, wherein said light color-converting material is one or more phosphorescent dyes.

17. The lighting assembly as recited in claim 11, wherein said light color-converting material is a combination of fluorescent dyes and/or phosphorescent dyes.

18. The lighting assembly as recited in claim 11, wherein said light-transmitting material is an acrylic resin.

19. The lighting assembly as recited in claim 18, wherein said light color-converting material is one or more fluorescent dyes mixed into said acrylic resin.

20. The lighting assembly as recited in claim 11, wherein the cross-sectional geometry for the inner cavity of the bulb is plotted by:

transposing the predetermined radiation pattern of the light-emitting diode onto an x-y coordinate system;

superimposing the bulb onto the x-y coordinate system, with the inner cavity of the bulb initially having a generally circular cross-section defining a boundary;

measuring a radial distance that the predetermined radiation pattern extends past the light-emitting surface of the bulb at selected angles on the x-y coordinate system; and

adding the measured radial distance at each selected angle to the generally circular cross-section of the inner cavity, extending the boundary of the inner cavity at each selected angle to plot the cross-sectional geometry for the inner cavity.