Light emitting diode illumination system

• US 9,068,703 B2
• Filed: 01/06/2014
• Issued: 06/30/2015
• Est. Priority Date: 08/06/2007
• Status: Active Grant

• Current Assignee: Lumencor, Inc.
• Original Assignee: Lumencor, Inc.
• Inventors: Brukilacchio, Thomas J., Conner, Arlie R.
• Primary Examiner(s): Ton, Tri T
• Application Number:
  US14/148,005
• Publication Number:
  US 20140119006A1
• Time in Patent Office: 540 Days
• Field of Search: None
• US Class Current: 1/1
• CPC Class Codes: A61B 1/00163 Optical arrangements A61B1/002, A61B1/06 take precedence
• CPC Class Codes: A61B 1/0653 with wavelength conversion
• CPC Class Codes: A61B 1/0669 at proximal end of an endoscope
• CPC Class Codes: A61B 1/0684 using light emitting diodes [LED]
• CPC Class Codes: A61N 2005/005 for cooling the radiator
• CPC Class Codes: A61N 2005/0652 Arrays of diodes
• CPC Class Codes: A61N 5/062 Photodynamic therapy, i.e. excitation of an agent
• CPC Class Codes: F21K 9/60 Optical arrangements integrated in the light source, e.g. for improving the colour rendering index or the light extraction
• CPC Class Codes: F21K 9/61 using light guides
• CPC Class Codes: F21K 9/64 using wavelength conversion means distinct or spaced from the light-generating element, e.g. a remote phosphor layer
• CPC Class Codes: F21V 13/04 the elements being reflectors and refractors for vehicle rear lights F21S43/40
• CPC Class Codes: F21V 13/08 the elements being filters or photoluminescent elements and reflectors
• CPC Class Codes: F21V 13/14 the elements being filters or photoluminescent elements, reflectors and refractors
• CPC Class Codes: F21V 29/60 characterised by the use of a forced flow of gas, e.g. air
• CPC Class Codes: F21V 29/70 characterised by passive heat-dissipating elements, e.g. heat-sinks
• CPC Class Codes: F21V 5/008 Combination of two or more successive refractors along an optical axis
• CPC Class Codes: F21V 7/0066 specially adapted to cooperate with point like light sources; specially adapted to cooperate with light sources the shape of which is unspecified F21V7/16 - F21V7/30 take precedence
• CPC Class Codes: F21V 9/30 Elements containing photoluminescent material distinct from or spaced from the light source shades F21V1/17; globes, bowls or cover glasses F21V3/08, F21V3/12; refractors F21V5/10; reflectors F21V7/26, F21V7/30; elements with provision for controlling the spectral properties or intensity F21V9/40
• CPC Class Codes: F21W 2131/205 for operating theatres
• CPC Class Codes: F21W 2131/40 Lighting for industrial, commercial, recreational or military use
• CPC Class Codes: F21Y 2105/00 : Planar light sources
• CPC Class Codes: F21Y 2113/00 : Combination of light sources
• CPC Class Codes: F21Y 2113/13 : comprising an assembly of point-like light sources
• CPC Class Codes: F21Y 2115/10 : Light-emitting diodes [LED]
• CPC Class Codes: F21Y 2115/30 : Semiconductor lasers
• CPC Class Codes: G01N 2021/6419 : Excitation at two or more wavelengths
• CPC Class Codes: G01N 2021/6482 : Sample cells, cuvettes
• CPC Class Codes: G01N 21/64 : Fluorescence; Phosphorescence
• CPC Class Codes: G01N 2201/0627 : Use of several LED's for spectral resolution
• CPC Class Codes: G02B 23/2469 : using optical fibres
• CPC Class Codes: G02B 27/0994 : Fibers, light pipes optical fibers per se G02B6/02
• 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 27/145 : having sequential partially reflecting surfaces
• CPC Class Codes: G02B 6/0006 : Coupling light into the fibre in general G02B6/4298

Abstract

The present invention provides a light engine having four light sources. A combination of collimators, bandpass filters, dichroic mirrors, and other elements is operative to direct light from the light sources onto a main optical axis from where it may be focused into a light guide for transport to an instrument or device. Particular embodiments of the invention provide for computer control, intensity control, color control, and light source modulation. Additional embodiments include particular light sources including light pipes and lasers. The light engine provides white light having a high color rendering index and suitable for applications in microscopy, endoscopy, and/or bioanalytical instrumentation.

Claims

1. A light engine for generating light for fluorescence microscopy, the light engine comprising:

a first light source, wherein the first light source includes a first Light Emitting Diode (LED), a first bandpass filter, and a first collimator, wherein the first light source is configured to emit a first collimated light beam of a first color suitable for exciting a first fluorescent label;

a second light source, wherein the second light source includes a second Light Emitting Diode (LED), a second bandpass filter, and a second collimator, wherein the second light source is configured to emit a second collimated light beam of a second color different than the first color, the second color being suitable for exciting a second fluorescent label;

a third light source, wherein the third light source includes a third Light Emitting Diode (LED), a third bandpass filter, and a third collimator, wherein the third light source is configured to emit a third collimated light beam of a third color different than the first color and second color, the third color being suitable for exciting a third fluorescent label;

a fourth light source, wherein the fourth light source includes a fourth Light Emitting Diode (LED), a fourth bandpass filter, and a fourth collimator, wherein the fourth light source is configured to emit a fourth collimated light beam of a fourth color different than the first color, second color, and third color, the fourth color being suitable for exciting a fourth fluorescent label;

a plurality of optical components positioned so as to direct each of the first collimated light beam, the second collimated light beam, the third collimated light beam, and the fourth collimated light beam onto a main optical axis of the light engine; and

a lens positioned to receive light directed by the plurality of optical components onto the main optical axis of the light engine and direct a beam of output light into one of a liquid light guide, fiber bundle light guide, and a Kohler Illuminator.

2. The light engine of claim 1, further comprising a laser light source, wherein the laser light source emits a coherent light beam, and wherein the plurality of optical components also direct the coherent light beam onto the main optical axis.

3. The light engine of claim 1, further comprising Kohler adaptation optics positioned to receive said beam of output light from said lens.

4. The light engine of claim 1, wherein the light engine is computer controllable.

5. The light engine of claim 1, wherein the beam of output light is spectrally tunable.

6. The light engine of claim 1, wherein each of the first light source, the second light source, the third light source, the fourth light source has an adjustable intensity.

7. The light engine of claim 1, further comprising a first laser light source which emits a first coherent light beam of a first wavelength and a second laser light source which emits a second coherent light beam of a second wavelength, and wherein the plurality of reflective optical components also direct the first coherent light beam and second coherent light beam onto the main optical axis.

8. The light engine of claim 1, wherein said first Light Emitting Diode (LED) of said first light source emits light of an excitation color different than said first color, and wherein said first light source further comprises a luminescent component comprising a luminescent material which receives said light of said excitation color and, in response, emits light of said first color which passes through said first bandpass filter, and said first collimator to generate said first collimated light beam of said first color.

9. The light engine of claim 1, wherein each of said first light source, second light source, third light source and fourth light source is independently controllable such that said beam of output light can comprise a single one of said first color, second color, third color, and fourth color or a mixture of two or more of said first color, second color, third color, and fourth color.

10. A light engine, for generating white light for endoscopy or microscopy, the light engine comprising:

a first light source, wherein the first light source includes a first Light Emitting Diode (LED) and a first collimator, wherein the first light source emits a first collimated light beam of a first color;

a second light source, wherein the second light source includes a second Light Emitting Diode (LED) and a second collimator, wherein the second light source emits a second collimated light beam of a second color different than the first color;

a third light source, wherein the third light source includes a third Light Emitting Diode (LED) and a third collimator, wherein the third light source emits a third collimated light beam of a third color different than the first color and second color;

a fourth light source, wherein the fourth light source includes a fourth Light Emitting Diode (LED) and a fourth collimator, wherein the fourth light source emits a fourth collimated light beam of a fourth color different than the first color, second color, and third color;

a plurality of reflective optical components positioned so as to combine the first collimated light beam of the first color, the second collimated light beam of the second color, the third collimated light beam of the third color, the fourth collimated light beam of the fourth color, on a main optical axis of the light engine to generate a beam of white light having a color rendering index greater than 85; and

a lens for focusing the beam of white light into a light guide for transmission to a microscope or endoscope.

11. The light engine of claim 10, wherein said first Light Emitting Diode (LED) of said first light source emits light of an excitation color different than said first color, and wherein said first light source further comprises a luminescent component comprising a luminescent material which receives said light of said excitation color and, in response, emits light of said first color which passes through said first collimator to generate said first collimated light beam of said first color.

12. The light engine of claim 10, wherein the light engine is computer controllable.

13. The light engine of claim 10, wherein the beam of white light is spectrally tunable.

14. The light engine of claim 10, in combination with a light guide positioned to receive said beam of white light from said lens, and wherein the light guide is adapted to transport said beam of white light to said microscope or endoscope.

15. The light engine of claim 10, further comprising a laser light source, wherein the laser light source emits a coherent light beam, and wherein the plurality of reflective optical components also direct the coherent light beam onto the main optical axis.

16. The light engine of claim 10, wherein each of the first light source, the second light source, the third light source, the fourth light source has an adjustable intensity.

17. The light engine of claim 10, wherein said plurality of reflective elements comprise a plurality of dichroic reflective elements.

18. The light engine of claim 10, further comprising a first laser light source which emits a first coherent light beam of a first wavelength and a second laser light source which emits a second coherent light beam of a second wavelength, and wherein the plurality of reflective optical components also direct the first coherent light beam and second coherent light beam onto the main optical axis.

19. The light engine of claim 10, wherein said first light source includes a first bandpass filter, said second light source includes a second bandpass filter, said third light source includes a third bandpass filter, and said fourth light source includes a fourth bandpass filter.

20. The light engine of claim 10, wherein said beam of white light has an optical power equivalent to output from a compact arc lamp.

21. The light engine of claim 10, wherein each of said first light source, second light source, third light source, and fourth light source can be modulated at rates exceeding 10 KHz.