Combining outputs of different light sources

• US 20080074752A1
• Filed: 08/08/2007
• Published: 03/27/2008
• Est. Priority Date: 04/23/2004
• Status: Active Grant

• Current Assignee: Light Prescriptions Innovators, LLC
• Original Assignee: Light Prescriptions Innovators, LLC
• Inventors: Falicoff, Waqidi, Benitez, Pablo, Parkyn, William, Chaves, Julio, Minano, Juan
• Granted Patent: US 7,724,440 B2
• Time in Patent Office: Days
• US Class Current: 359/641
• CPC Class Codes: F21K 9/68 Details of reflectors forming part of the light source
• 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 19/0066 in the form of an LED array
• CPC Class Codes: G02B 27/1006 for splitting or combining different wavelengths G02B27/1086, G02B27/141 take precedence
• CPC Class Codes: G02B 27/143 using macroscopically faceted or segmented reflective surfaces
• CPC Class Codes: G02B 27/149 using crossed beamsplitting surfaces, e.g. cross-dichroic cubes or X-cubes
• CPC Class Codes: G02B 6/0018 Redirecting means on the surface of the light guide
• CPC Class Codes: G02B 6/0028 Light guide, e.g. taper
• CPC Class Codes: H04N 9/315 Modulator illumination systems general applications of lighting devices F21V; general optical systems G02B; lamp houses for projectors not peculiar to the presence of an electronic spatial light modulator G03B21/20

Abstract

An embodiment of an optical manifold has first and second collimators, each arranged to receive light from a source and transmit the light to an exit port of the collimator, and a separator arranged to emit some of the light from the exit ports of the first and second collimators and to recycle some of the light into the collimators. Another embodiment has at least three collimators of substantially equal length and having central axes, respective light sources at entry ports of the collimators, the collimators being arranged with their central axes parallel and with their light sources in a common plane and reflectors positioned to direct light from exit ports of the collimators to a selectively reflective component that guides all the light into a common exit beam.

Claims

1. An optical manifold comprising:

first and second collimators, each arranged to receive light from a source and transmit the light to an exit port of the collimator; and

a separator arranged to emit some of the light from the exit ports of the first and second collimators and to recycle some of the light into the collimators.

2. The manifold of claim 1, wherein the first and second collimators are substantially identical, and the light emitted from the exit ports of the collimators has a greater total flux than a notional single substantially identical collimator without a separator, and has less than a proportionately greater é

tendue.

3. The manifold of claim 2, wherein the light emitted from the exit ports of the collimators has between 1.3 and 1.7 times the total flux of the notional single substantially identical collimator, and has an é

tendue substantially equal to that of the notional single substantially identical collimator.

4. The manifold of claim 1, wherein the first and second collimators are arranged with their exit ports side by side, and wherein the separator comprises reflectors covering non-adjacent parts of the exit ports.

5. The manifold of claim 1, wherein the first and second collimators are arranged with their exit ports facing, and the separator comprises reflectors directing part of the light from the exit ports of the collimators to an exit port of the optical manifold, and permitting another part of the light to pass from one of the first and second collimators into the other of the first and second collimators.

6. The manifold of claim 1, further comprising at least one third collimator arranged to receive light from a source and transmit the light to an exit port of the collimator and a selectively reflective component arranged to combine light emitted by the first and second collimators and light emitted by the at least one third collimator.

7. The manifold of claim 6, further comprising light sources operatively connected to supply light to entry ports of the collimators, wherein the light supplied to the at least one third collimator is of at least one color different from the light supplied to the first and second collimators, and wherein the selectively reflective component comprises at least one component arranged to reflect light of one of the colors and to transmit light of another of the colors.

8. The manifold of claim 7, wherein the collimators are of substantially equal length, and are arranged with central axes parallel and with their light sources in a common plane at the entry ports of the collimators, and wherein each of the collimators is connected to the selectively reflective component by a prism such that the optical path length from an exit port of the collimator to an exit port of the optical manifold is substantially identical for all of the collimators.

9. An optical manifold comprising:

at least three collimators of substantially equal length and having central axes;

respective light sources at entry ports of the collimators; and

a component arranged to combine the light into a common light output, wherein the mean optical path lengths form the exit ports of the collimators to the common light output are substantially equal.

10. The optical manifold according to claim 9, wherein the at least three collimators are of substantially equal length, have central axes, and are arranged with their central axes parallel and with their light sources in a common plane;

and

the manifold further comprising reflectors positioned to direct light from exit ports of the collimators to the component arranged to combine the light.

11. The optical manifold according to claim 10, wherein the reflectors are prisms.

12. The optical manifold according to claim 9, wherein the light sources are not all of the same color, and the component arranged to combine the light comprises at least one frequency-selective mirror.

13. The optical manifold according to claim 9, wherein the light sources comprise at least one LED and at least one phosphor, further comprising an LED arranged to excite the phosphor.

14. The optical manifold according to claim 9, wherein the at least three collimators include first and second collimators, each arranged to receive light from a source and transmit the light to an exit port of the respective collimator;

and

a separator arranged to emit some of the light from the exit ports of the first and second collimators and to recycle some of the light into the collimators.

15. An optical source comprising:

a housing having reflective interior surfaces and at least one opening;

a phosphor within the housing arranged to be excited by light of a first dominant color through the opening in the housing and to emit light of a second dominant color in response thereto; and

a light source of a third dominant color, to which the phosphor is transparent, arranged to emit light into the interior of the housing.

16. The optical source of claim 15, wherein the housing comprises a box with one open side in communication with a collimator and concentrator that concentrates light of the first dominant color into the box and collimates light of the second and third dominant colors emitted from the box.

17. The optical source of claim 15, wherein the light source of the third dominant color is a light-emitting diode.

18. The optical source of claim 17, wherein the first dominant color is blue, the second dominant color is green, and the third dominant color is red.

19. The optical source of claim 18, further comprising a first source of blue light arranged to excite the phosphor and a second source of blue light that is combined with the red light from the third source and the green light from the phosphor, and wherein the arrangement is such that the combined light has the visual appearance of a desired white.