Apparatus and method for improved illumination area fill

• US 20050219840A1
• Filed: 03/30/2005
• Published: 10/06/2005
• Est. Priority Date: 03/30/2004
• Status: Active Grant

• Current Assignee: Signify Holding B.V. (Signify N.V.)
• Original Assignee: Illumination Management Solutions Incorporated (Eaton Corporation PLC.)
• Inventors: Holder, Ronald G., Rhoads, Greg
• Granted Patent: US 7,172,319 B2
• Time in Patent Office: Days
• US Class Current: 362/187
• CPC Class Codes: F21K 9/233 specially adapted for generating a spot light distribution, e.g. for substitution of reflector lamps
• CPC Class Codes: F21V 13/04 the elements being reflectors and refractors for vehicle rear lights F21S43/40
• CPC Class Codes: F21V 7/0091 using total internal reflection
• CPC Class Codes: F21V 7/04 Optical design
• CPC Class Codes: F21V 7/09 with a combination of different curvatures
• CPC Class Codes: F21Y 2115/10 Light-emitting diodes [LED]
• CPC Class Codes: G02B 19/0028 refractive and reflective surfaces, e.g. non-imaging catadioptric systems
• CPC Class Codes: G02B 19/0061 the light source comprising a LED semiconductor devices with at least one potential-jump barrier or surface barrier specially adapted for light emission H01L33/00
• CPC Class Codes: H01L 33/58 Optical field-shaping elements
• CPC Class Codes: H01L 33/60 Reflective elements

Abstract

A reflector for a light source, such as an LED, is provided with a shape which efficiently collects and directs energy to an illumined surface whereby almost 100% of the light is collected and distributed into a designer composite beam. The shape in one embodiment is comprised of three zones beginning with a parabolic surface of revolution at the base of the reflector, followed by a transition or straight conic zone and ending with an elliptical zone. In another embodiment the reflector shape is determined according to a transfer function which allows for arbitrary designer control of the reflected rays at each point on the reflector, which when combined with direct radiation from the source, results in a designer controlled composite beam or illumination. The device is more than 90% energy efficient and allows replacement of higher power, less energy efficient light sources with no loss in illumination intensity.

Claims

1. An apparatus for illuminating a surface comprising:

a light source whose intensity varies as a function of the angles of the light rays radiated from the light source in a three dimensional radiation pattern, and

a reflector having a base and aperture, the reflector being proximate to the light source, defining a system half angle by its aperture and allowing directly radiated energy to propagate from the light source through the aperture of the reflector to the surface to provide a directly radiated energy distribution pattern on the surface, the reflector having three distinct conic shaped zones, each providing a surface of revolution, the first zone being parabolic, the second zone being a straight conic and the third zone being elliptical, in that order, beginning with the base of the reflector and moving toward its aperture, to provide a designer controlled reflected energy distribution pattern overlaid onto the directly radiated energy distribution pattern on the surface, which reflected energy distribution pattern combines with the directly radiated energy distribution pattern to produce a designer controlled composite energy distribution pattern on the surface.

2. The apparatus of claim 1 where substantially all the light generated from the light source is in the designer controlled composite energy distribution pattern on the surface.

3. The apparatus of claim 1 where at least 90% of the light generated from the light source is in the designer controlled composite energy distribution pattern on the surface.

4. The apparatus of claim 1 where the reflector comprises a total internal reflector (TIR).

5. The apparatus of claim 4 where the light source comprises an LED light source and where the total internal reflector (TIR) is integrally manufactured as a package covering for or is optically integrated with the LED light source.

6. The apparatus of claim 4 where the total internal reflector has an exterior surface and further comprising a reflective coating disposed on a selected portion of the total internal reflector to insure internal reflection of light therein.

7. The apparatus of claim 5 where the total internal reflector has an exterior surface and further comprising a reflective coating disposed on a selected portion of the total internal reflector to insure internal reflection of light therein.

8. The apparatus of claim 1 further comprising a solid or stranded optical fiber where the designer controlled composite energy distribution pattern is into the solid or stranded optical fiber.

9. The apparatus of claim 1 further comprising a light fixture in which the light source and reflector are included.

10. The apparatus of claim 9 where the light fixture comprises a PAR fixture, an MR fixture, a street lamp, an array, or an LCD panel light, signage light, airplane light, auto light, marine light, indoor or outdoor architectural light, decorative light, task light, or flood light.

11. A method for illuminating a surface comprising:

directly radiating light from a light source whose intensity varies as a function of the three dimensional solid angles of the light rays radiated from the light source, and

reflecting light from a reflector having a base and aperture, the reflector being proximate to the light source, defining a system half angle by its aperture and allowing directly radiated energy to propagate from the light source to the surface to provide a directly radiated energy distribution pattern on the surface, the reflector having three distinct conic shaped zones, each providing a surface of revolution, the first zone being parabolic, the second zone being a straight conic and the third zone being elliptical, in that order, beginning with the base of the reflector and moving toward its aperture, to provide a designer controlled reflected energy distribution pattern overlaid onto the directly radiated energy distribution pattern on the surface, which reflected energy distribution pattern combines with the directly radiated energy distribution pattern to produce a designer controlled composite energy distribution pattern on the surface.

12. The method of claim 11 where directly radiating and reflecting light substantially transmits all the light generated from the light source into the designer controlled composite energy distribution pattern on the surface.

13. The method of claim 11 where directly radiating and reflecting light transmits at least 90% of the light generated from the light source into the designer controlled composite energy distribution pattern on the surface.

14. A method of computerized design of a shape of a reflector having a three dimensional surface, a base and aperture, the reflector for reflecting light from a light source whose intensity varies as a function of three dimensional solid angles of the light rays radiated from the light source comprising:

characterizing the entire intensity and spatial distribution pattern of light radiating from the light source as data in a computer;

determining the desired energy pattern at a destination as a final data solution in the computer;

determining the desired distance from light source to the destination as a data input to the computer;

deriving the desired two dimensional half angle from the data, measured from the common axis of the light source and reflector, including determining the reflector height and aperture width, to allow directly radiated light to propagate from the light source to the destination;

calculating the remainder of the difference between the total available light from the light source less the directly radiated light; and

defining the three dimensional surface of the reflector as three distinct conic shaped zones, each providing a surface of revolution, the first zone being parabolic, the second zone being a straight conic and the third zone being elliptical, in that order, beginning with the base of the reflector and moving toward its aperture, to provide a designer controlled reflected light overlaid onto the directly radiated light, which reflected light combines with the directly radiated light to form a user-defined composite light pattern at the destination.

15. An apparatus for illuminating a surface comprising:

a light source whose intensity varies as a function of the angles of the light rays radiated from the light source in a three dimensional radiation pattern, and

a reflector having an aperture, the reflector being proximate to the light source, defining a system angle by its aperture and allowing directly radiated energy to propagate from the light source through the aperture of the reflector to the surface to provide a directly radiated energy distribution pattern on the surface,

where the reflector has a defined shape derived from a transfer function, which has as inputs;

the three dimensional radiation pattern of the light source;

beam parameters, such as light source-to-surface distance and beam diameter;

system parameters of the reflector such as reflector size and aperture size of the reflector; and

a desired composite energy distribution on the surface; and

which has as outputs;

an amount of directly radiated energy propagating through the aperture of the reflector;

a remainder of the total available radiated energy from the light source less the energy of the light directly radiating to the surface through the reflector aperture; and

a calculated position and orientation of each point on the reflector as a function of angle needed to provide the desired composite energy distribution on the surface, which calculation defines the shape of the reflector necessary to provide a reflected energy pattern to overlay the directly radiated energy pattern to form the designer controlled composite energy distribution on the surface.

16. The apparatus of claim 15 where substantially all the light generated from the light source is in the designer controlled composite energy distribution pattern on the surface.

17. The apparatus of claim 15 where at least 90% of the light generated from the light source is in the designer controlled composite energy distribution pattern on the surface.

18. The apparatus of claim 15 where the reflector comprises a total internal reflector (TIR).

19. The apparatus of claim 18 where the light source comprises an LED light source and where the total internal reflector (TIR) is integrally manufactured as a package covering for or is optically integrated with the LED light source.

20. The apparatus of claim 18 where the total internal reflector has an exterior surface and further comprising a reflective coating disposed on a selected portion of the total internal reflector to insure internal reflection of light therein.

21. The apparatus of claim 19 where the total internal reflector has an exterior surface and further comprising a reflective coating disposed on a selected portion of the total internal reflector to insure internal reflection of light therein.

22. The apparatus of claim 15 further comprising a solid or stranded optical fiber where the designer controlled composite energy distribution pattern is into the solid or stranded optical fiber.

23. The apparatus of claim 15 further comprising a light fixture in which the light source and reflector are included.

24. The apparatus of claim 23 where the light fixture comprises a PAR fixture, an MR fixture, a street lamp, an array, or an LCD panel light, signage light, airplane light, auto light, marine light, indoor or outdoor architectural light, decorative light, task light, or flood light.

25. A method for illuminating a surface comprising:

radiating light from a light source whose intensity varies as a function of the angles of the light rays radiated from the light source in a three dimensional radiation pattern, and

reflecting light from a reflector having an aperture, the reflector being proximate to the light source, defining a system angle by its aperture and allowing directly radiated energy to propagate from the light source through the aperture of the reflector to the surface to provide a directly radiated energy distribution pattern on the surface,

where the reflector has a defined shape derived from a transfer function, which has as inputs;

the three dimensional radiation pattern of the light source;

beam parameters, such as light source-to-surface distance and beam diameter;

system parameters of the reflector such as reflector size and aperture size of the reflector; and

a desired composite energy distribution on the surface;

and which has as outputs;

an amount of directly radiated energy propagating through the aperture of the reflector;

a remainder of the total available radiated energy from the light source less the energy of the light directly radiating to the surface through the reflector aperture; and

a calculated position and orientation of each point on the reflector as a function of angle needed to provide the desired composite energy distribution on the surface, which calculation defines the shape of the reflector necessary to provide a reflected energy pattern to overlay the directly radiated energy pattern to form the designer controlled composite energy distribution on the surface.

26. The method of claim 25 where directly radiating and reflecting light substantially transmits all the light generated from the light source into the designer controlled composite energy distribution pattern on the surface.

27. The method of claim 25 where directly radiating and reflecting light transmits at least 90% of the light generated from the light source into the designer controlled composite energy distribution pattern on the surface.

28. A method of computerized design of a shape of a reflector having a three dimensional surface, a base and aperture, the reflector for reflecting light from a light source whose intensity varies as a function of three dimensional angles of light rays radiated from the light source comprising defining a shape for the reflector which shape is derived from a transfer function in a computer, which transfer function comprises inputting:

the three dimensional radiation pattern of the light source;

beam parameters, such as light source-to-surface distance and beam diameter;

system parameters of the reflector such as reflector size and aperture size of the reflector; and

a desired composite energy distribution on the surface; and

outputting;

an amount of directly radiated energy propagating through the aperture of the reflector;

a remainder of the total available radiated energy from the light source less the energy of the light directly radiating to the surface through the reflector aperture; and

a calculated position and orientation of each point on the reflector as a function of angle needed to provide the desired composite energy distribution on the surface, which calculation defines the shape of the reflector necessary to provide a reflected energy pattern to overlay the directly radiated energy pattern to form the designer controlled composite energy distribution on the surface.

29. An apparatus for illuminating a surface with an arbitrarily selected composite energy distribution comprising:

a light source, and

a reflector having an aperture, the reflector being proximate to the light source, light being directly radiated from the light source through the aperture of the reflector to the surface to provide a directly radiated energy distribution pattern on the surface,

where the reflector has a selectively defined shape at each point with a selectively defined spatial position and selectively defined orientation derived from the arbitrarily selected composite energy distribution, which reflector generates a reflected energy distribution onto the surface, which when overlaid onto the directly radiated energy distribution pattern on the surface produces the arbitrarily selected composite energy distribution on the surface.

30. An apparatus for illuminating a surface comprising:

a light source whose intensity varies as a function of the three dimensional solid angles of the light rays radiated from the light source, and

a reflector having a base and aperture, the reflector being proximate to the light source, defining a system angle by its aperture and allowing directly radiated energy to propagate from the light source through the aperture of the reflector to the surface to provide a directly radiated energy distribution pattern on the surface, the reflector having at least two conic shaped zones and another zone, each providing a surface of revolution, the first zone being parabolic, the second zone being a transition surface and the third zone being elliptical, in that order, beginning with the base of the reflector and moving toward its aperture, the transition surface extending between the first and third zones, to provide a designer controlled reflected energy distribution pattern overlaid onto the directly radiated energy distribution pattern on the surface, which reflected energy distribution pattern combines with the directly radiated energy distribution pattern to produce a designer controlled composite energy distribution pattern on the surface.

31. An apparatus for illuminating a surface comprising:

a light source, and

a reflector having an aperture, the reflector being proximate to the light source, and allowing directly radiated energy to propagate from the light source through the aperture of the reflector to the surface to provide a directly radiated energy distribution pattern on the surface,

where the reflector has a plurality of shaped zones, each zone for directing light into a selected portion of a composite energy distribution pattern on the surface to provide a designer controlled reflected energy distribution pattern overlaid onto the directly radiated energy distribution pattern on the surface to produce the composite energy distribution pattern on the surface.

32. An apparatus for illuminating a surface comprising:

a light source whose intensity varies as a function of the angles of the light rays radiated from the light source in a three dimensional radiation pattern, and

a reflector having a base and an aperture, the reflector receiving light from the light source,

where the light source is directed toward the base of the aperture and is disposed longitudinally forward of the base of the reflector, and

where the reflector has a defined shape derived from a transfer function, which has as inputs;

the three dimensional radiation pattern of the light source;

beam parameters, such as light source-to-reflector distance, reflector-to-surface distance, and beam diameter;

system parameters of the reflector such as reflector size and aperture size of the reflector; and

a desired energy distribution on the surface;

and which has as outputs;

an amount of radiated energy propagating through the aperture of the reflector; and

a calculated position and orientation of each point on the reflector as a function of angle needed to provide the desired energy distribution on the surface, which calculation defines the shape of the reflector necessary to provide a reflected energy pattern, where the transfer function configures the shape of the reflector to send reflected light from a first portion of the reflector extending from the base of the reflector to a predetermined demarcation on the reflector to an first portion of the energy distribution on the surface which is arbitrarily designer selected, and where the transfer function configures the shape of the reflector to send reflected light from a second portion of the reflector extending from the predetermined demarcation on the reflector to the aperture of the reflector to a second portion of the energy distribution on the surface which is arbitrarily designer selected.

33. An apparatus for illuminating a surface comprising:

a light source whose intensity varies as a function of the angles of the light rays radiated from the light source in a three dimensional radiation pattern,

a reflector having an aperture, the reflector being proximate to the light source, defining a system angle by its aperture, and

a lens for allowing radiated energy directly from the light source to propagate through the lens to the illuminated surface to provide a directed energy distribution pattern on the illuminated surface,

where the reflector has a surface and defined shape derived from a transfer function, which has as inputs;

the three dimensional radiation pattern of the light source;

beam parameters, such as light source-to-surface distance and beam diameter;

lens parameters,

system parameters of the reflector such as reflector size and aperture size of the reflector; and

a desired composite energy distribution on the illuminated surface;

and which has as outputs;

an amount of directed radiated energy propagating through the lens;

a remainder of the total available radiated energy from the light source less the energy of the directed light propagating to the illuminated surface through the lens; and

a calculated position and orientation of each point on the surface of the reflector as a function of angle needed to provide the desired composite energy distribution on the illuminated surface, which calculation defines the shape of the reflector necessary to provide a reflected energy pattern to overlay the directed energy pattern to form the designer controlled composite energy distribution on the surface.

34. The apparatus of claim 33 where the points of the surface of the reflector comprise a plurality of shaped surface zones, each surface zone for directing light into a selected portion of a composite energy distribution pattern on the surface to provide a designer controlled reflected energy distribution pattern overlaid onto the directed energy distribution pattern on the illuminated surface to produce the composite energy distribution pattern on the illuminated surface.