SOLID STATE CONTINUOUS WHITE LIGHT SOURCE

• US 20130188388A1
• Filed: 01/15/2013
• Published: 07/25/2013
• Est. Priority Date: 01/20/2012
• Status: Active Grant

• Current Assignee: Lumencor, Inc.
• Original Assignee: Lumencor, Inc.
• Inventors: Jaffe, Steven M., Jaffe, Claudia B., Tylinski, George S.
• Granted Patent: US 8,967,811 B2
• Time in Patent Office: Days
• US Class Current: 362/580
• CPC Class Codes: A61B 1/0646 with illumination filters
• 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: F21V 7/00 Reflectors for light sources characterised by cooling arrangements F21V29/505
• CPC Class Codes: F21V 9/083 for portable lighting devices
• 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: G02B 21/16 adapted for ultraviolet illumination ; Fluorescence microscopes G02B21/0076 takes precedence
• CPC Class Codes: G02B 27/141 using dichroic mirrors
• CPC Class Codes: G02B 6/0001 specially adapted for lighting devices or systems lighting or signalling on vehicles using light guides B60Q1/00; lighting devices for vehicle dashboards B60Q3/10; lighting devices for vehicle interior using light guides B60Q3/62; lighting devices mounted on the vehicle rear part using light guides F21S43/235; measuring arrangements having light conducting pointers G01D13/265; illumination of liquid crystal displays G02F1/1336; illuminated signs G09F13/00
• CPC Class Codes: G02B 6/0003 the light guides being doped with fluorescent agents
• CPC Class Codes: G02B 6/0006 Coupling light into the fibre in general G02B6/4298
• CPC Class Codes: G02B 6/4296 coupling with sources of high radiant energy, e.g. high power lasers, high temperature light sources

Abstract

A solid state illumination system is provided as a replacement for conventional arc light, metal halide and Xenon white-light sources for applications in life sciences including, microscopy, fluorescence microscopy, and endoscopy. The solid state illumination system generates high quality white light output from LED light sources. The white light output is continuous in the visible spectrum from 380 nm to 650 nm and is suitable for imaging all the most common fluorophores and fluorescent proteins. In embodiments, an LED light pipe engine is used to generate a portion of the spectral content of the white light output. In alternative embodiments the solid state illumination system produces light output of a selectable color.

Claims

1. An illumination system comprising:

a housing enclosing a space;

a metal platform having a first substantially planar surface and a second surface;

the metal platform dividing the enclosed space into a first volume defined by the first substantially planar surface and the housing, and a second volume defined by the second surface and the housing;

a plurality of light sources positioned within said first volume, each light source having a solid state light source and a metal base and emitting a light beam;

each metal base of each of the plurality of light sources mounted to said substantially planar surface of said platform;

each metal base providing a heat conducting path between a solid state light source and the metal platform whereby heat generated by the solid state light source is conducted via the base to the platform; and

a fan configured to provide airflow through the second volume to dissipate heat from the second surface of the metal platform.

2. The illumination system of claim 1, further comprising a plurality of dichroic elements positioned in said first volume and mounted to said substantially planar surface of said platform wherein the plurality of dichroic elements combine the light beams from the plurality of light sources into a combined beam.

3. The illumination system of claim 2, further comprising an output optical stage positioned in said first volume and mounted to said substantially planar surface of said platform and adapted to receive the combined beam and focus the combined beam into an entrance aperture of a light guide.

4. The illumination system of claim 3, in combination with a light guide coupled to the output optical stage through an aperture in said housing, the light guide adapted to transmit the combined beam from the illumination source to an optical instrument wherein the optical instrument.

5. The illumination system of claim 1, further comprising a control board mounted within the second volume of the housing, the control board adapted to provide current to said plurality of light sources and said fan.

6. The illumination system of claim 5, wherein each of said plurality of light sources is provided with a thermal sensor, wherein the thermal sensors are coupled to said control board and wherein said control board is adapted to control the speed of the fan in response to an output of said thermal sensors.

7. The illumination system of claim 1, wherein the first volume is separated from the second volume so as to prevent contaminants in said airflow through the second volume from entering the first volume.

8. The illumination system of claim 1, wherein at least one of said plurality of light sources includes a luminescent rod light source which comprises:

a plurality of light emitting diodes which emit light of a first color;

a luminescent rod positioned to receive the light of the first color, wherein the light of the first color is absorbed by the luminescent rod which then emits by fluorescence a light of a second color different than the first color; and

rod optics adapted to extract the light of a second color from the luminescent rod and collimate the light of a second color onto a light beam.

9. The illumination system of claim 1, wherein at least one of said plurality of light sources includes a luminescent rod light source which comprises:

a plurality of light emitting diodes which emit blue light;

a luminescent rod positioned to receive the blue light, wherein the blue light is absorbed by the luminescent rod which then emits by fluorescence green light; and

rod optics adapted to extract the green light from the luminescent rod and collimate the green light into a light beam.

10. The illumination system of claim 1, further comprising a plurality of dichroic elements positioned in said first volume and mounted to said substantially planar surface of said platform wherein the plurality of dichroic elements combine the light beams from the plurality of light sources into a combined beam of white light which has a spectral power which substantially equals or exceeds a spectral power of a 150 W Xenon lamp over substantially all of the visible spectrum from 380 nm to 650 nm.

11. An illumination system comprising:

a housing enclosing a space;

a metal platform having a first substantially planar surface and a second surface;

the metal platform dividing the enclosed space into a first volume defined by the first substantially planar surface and the housing, and a second volume defined by the second surface and the housing;

a luminescent rod light source which includes a first plurality of light emitting diodes which emit light of a first color, and a luminescent rod positioned to receive and absorb the light of the first color, wherein the luminescent rod, in response to absorbing light of the first color, by fluorescence light of a fluorescent color different than the first color, the luminescent rod and the plurality of light emitting diodes mounted to a first metal base; and

an LED light source which includes a second plurality of light emitting diodes which emit light of a second color different than the fluorescent color, the second plurality of light emitting diodes mounted to a second metal base;

the first metal base and the second metal base mounted to said substantially planar surface of said platform and whereby heat generated by the first plurality of light emitting diodes, second plurality of light emitting diodes and luminescent is conducted to the platform; and

a fan configured to provide airflow through the second volume to dissipate heat from the second surface of the metal platform.

12. The illumination system of claim 11, further comprising a plurality of dichroic elements positioned in said first volume and mounted to said substantially planar surface of said platform wherein the plurality of dichroic elements combine the second light and the fluorescent light into a combined beam.

13. The illumination system of claim 12, further comprising an output optical stage positioned in said first volume and mounted to said substantially planar surface of said platform and adapted to receive the combined beam and focus the combined beam into an entrance aperture of a light guide.

14. The illumination system of claim 13, in combination with a light guide coupled to the output optical stage through an aperture in said housing, the light guide adapted to transmit the combined beam from the illumination source to an optical instrument wherein the optical instrument.

15. The illumination system of claim 11, further comprising a control board mounted within the second volume of the housing, the control board adapted to provide current to said plurality of light sources and said fan.

16. The illumination system of claim 15, wherein the first metal base and the second metal base are each provided with a thermal sensor, wherein the thermal sensors are coupled to said control board and wherein said control board is adapted to control the speed of the fan in response to an output of said thermal sensors.

17. The illumination system of claim 11, wherein the first volume is separated from the second volume so as to prevent contaminants in said airflow through the second volume from entering the first volume.

18. The illumination system of claim 11, further comprising:

another LED light source which includes a third plurality of light emitting diodes which emit light of a third color different than the fluorescent color and the second color, the second plurality of light emitting diodes mounted to a third metal base;

wherein the third metal base is mounted to said substantially planar surface of said platform such that heat generated by the third plurality of light emitting diodes is conducted to the platform.

19. The illumination system of claim 11, wherein the first color is blue and the fluorescent color is green.

20. The illumination system of claim 11, further comprising a plurality of dichroic elements positioned in said first volume and mounted to said substantially planar surface of said platform wherein the plurality of dichroic elements combine the fluorescent light and the second light into a combined beam of white light which has a spectral power which substantially equals or exceeds a spectral power of a 150 W Xenon lamp over substantially all of the visible spectrum from 380 nm to 650 nm.