Apparatus and method for improved illumination area fill

• US 7,172,319 B2
• Filed: 03/30/2005
• Issued: 02/06/2007
• 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
• Primary Examiner(s): O'Shea; Sandra
• Assistant Examiner(s): Choi; Jacob Y.
• Application Number:
  US11/093,988
• Publication Number:
  US 20050219840A1
• Time in Patent Office: 678 Days
• Field of Search: 362/327, 362/341, 362/347, 362/297, 362/346, 362/348, 362/296, 362/514, 362/517, 362/518, 313/113, 359/868, 359/869, 359726-728, 359709-712
• US Class Current: 362/341
• 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 form the light source in a three dimensional radiation pattern, and a reflector having an optical aperture, the reflector being proximate to the light source, defining a system angle by the optical aperture of the reflector and allowing directly radiated energy to propagate from the light source through the optical 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, including light source-to-surface distance and beam diameter;

system parameters of the reflector including reflector size and optical 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 optical 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 optical aperture; and

a calculated position and orientation of each point on the reflector as a function of angle needed to provided 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.

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 coupled 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. An apparatus for illuminating a surface comprising:

a light source whose intensity varies as a function of the angles of the light rays radiated form the light source in a three dimensional radiation pattern, and a reflector having a base and an optical aperture, the reflector receiving light from the light source, where the light source is directed toward the base of the optical 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, including light source-to-reflector distance, reflector-to-surface distance, and beam diameter;

system parameters of the reflector including reflector size and optical 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 optical 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 optical aperture of the reflector to a second portion of the energy distribution on the surface which is arbitrarily designer selected.

12. 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 the aperture of the reflector, 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, including light source-to-surface distance and beam diameter;

lens parameters,

system parameters of the reflector including 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.

13. The apparatus of claim 12 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.

14. 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 means for reflecting light, the means having an optical aperture, and means for reflecting light, the means having an optical aperture, the means being proximate to the light source, defining a system angle by the optical aperture of the means and allowing directly radiated energy to propagate from the light source through the optical aperture of the means to the surface to provide a directly radiated energy distribution pattern on the surface, where the means has a defined shape derived from a transfer function, which has as inputs;

the three dimensional radiation pattern of the light source;

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

system parameters of the means including means size and optical aperture size of the means; and

a desired composite energy distribution on the surface; and

which has as outputs;

an amount of directly radiated energy propagating through the optical aperture of the means;

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 means optical aperture; and

a calculated position and orientation of each point on the means as a function of angle needed to provide the desired composite energy distribution on the surface, which calculation defines the shape of the means 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.