Solid state continuous white light source

• US 9,103,528 B2
• Filed: 01/15/2013
• Issued: 08/11/2015
• 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.
• Primary Examiner(s): Mai, Anh
• Assistant Examiner(s): FEATHERLY, HANA SANEI
• Application Number:
  US13/741,480
• Publication Number:
  US 20130188384A1
• Time in Patent Office: 938 Days
• Field of Search: 362/555
• US Class Current: 1/1
• 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. A light source comprising:

a rod comprising a luminescent material;

the rod having a first end opposite a second end, an elongated top surface opposite an elongated bottom surface, and first and second side surfaces disposed between the elongated top surface and the elongated bottom surface;

a metal base having a raised spine having a contact surface adapted to contact substantially all of the elongated bottom surface of the rod;

a fin having a first fin end, a second fin end, and an edge adapted to contact substantially all of the elongated top surface of the rod;

a spring configured and positioned to apply a force to said fin to push the edge against the elongated top surface of the rod whereby the elongated bottom surface of the rod is held in thermal contact with the contact surface of the spine of the metal base;

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

the plurality of light emitting diodes positioned adjacent the first and second side surfaces of the rod such that the first light of a first color enters the rod through the first and second side surfaces and is absorbed by the luminescent material which in response emits by fluorescence second light of a second color different than the first color which second light is transmitted along said rod to said first end and second end; and

wherein the rod is temperature regulated by transmission of heat from the rod to the spine of the metal base.

2. The light source of claim 1, further comprising:

a first end plate mounted to the base, the first end plate having a first slot aligned with the spine;

wherein the first end of the rod is received through said first slot such that the rod is aligned with the spine by said first end plate.

3. The light source of claim 2, further comprising:

a second end plate mounted to the base, the second end plate having a second slot aligned with the spine;

wherein the second end of the rod is received through said second slot such that the rod is aligned with the spine by said second end plate.

4. The light source of claim 1, further comprising:

a first end plate mounted to the base, the first end plate having a first slot aligned with the spine;

wherein the first end of the rod and the first fin end of the fin are received through said first slot such that the fin is aligned with the rod and the rod is aligned with the spine by said first end plate.

5. The light source of claim 4, further comprising:

a second end plate mounted to the base, the second end plate having a second slot aligned with the spine;

wherein the second end of the rod and the second fin end of the fin are received through said second slot such that the fin is aligned with the rod and the rod is aligned with the spine by said second end plate.

6. The light source of claim 1, further comprising:

a temperature sensor mounted in thermal contact with the base to monitor the temperature of the base.

7. The light source of claim 1, further comprising a heat sink mounted to said base.

8. The light source of claim 1, further comprising a fan for cooling the base.

9. The light source of claim 1, further comprising a mirror coupled to the second end of the rod to reflect the second light towards the first end of the rod.

10. The light source of claim 9, further comprising a spring which resiliently holds the mirror against the second end of the rod to accommodate thermal expansion of the rod.

11. A light source comprising:

a rod comprising a luminescent material;

the rod having a first end opposite a second end, an elongated top surface opposite an elongated bottom surface, and first and second side surfaces disposed between the elongated top surface and the elongated bottom surface;

a plurality of light emitting diodes which emit first light of a first color, the plurality of light emitting diodes positioned adjacent at least one of the first and second side surfaces of the rod such that the first light of a first color enters the rod through at least one of the first and second side surfaces and is absorbed by the luminescent material which in response emits by fluorescence second light of a second color different than the first color which second light is transmitted along said rod to said first end and second end;

a metal base including a raised spine having a contact surface adapted to contact substantially all of the elongated bottom surface of the rod;

a substantially planar fin having a first fin end, a second fin end, and an edge adapted to contact the elongated top surface of the rod; and

a spring configured and positioned to apply a force to said fin to push the edge against the elongated top surface of the rod whereby the elongated bottom surface of the rod is held against the contact surface of the spine of the metal base such that the rod temperature is regulated by transmission of heat from the rod to the spine of the metal base.

12. The light source of claim 11, further comprising:

a first end plate mounted to the base, the first end plate having a first slot aligned with the spine;

wherein the first end of the rod is received through said first slot such that the rod is aligned with the spine by said first end plate.

13. The light source of claim 12, further comprising:

a second end plate mounted to the base, the second end plate having a second slot aligned with the spine;

wherein the second end of the rod is received through said second slot such that the rod is aligned with the spine by said second end plate.

14. The light source of claim 11, further comprising:

a first end plate mounted to the base, the first end plate having a first slot aligned with the spine;

wherein the first end of the rod and the first fin end of the fin are received through said first slot such that the fin is aligned with the rod and the rod is aligned with the spine by said first end plate.

15. The light source of claim 14, further comprising:

a second end plate mounted to the base, the second end plate having a second slot aligned with the spine;

wherein the second end of the rod and the second fin end of the fin are received through said second slot such that the fin is aligned with the rod and the rod is aligned with the spine by said second end plate.

16. The light source of claim 11, further comprising:

a temperature sensor mounted in thermal contact with the base to monitor the temperature of the base.

17. The light source of claim 11, further comprising a heat sink mounted to said base.

18. The light source of claim 11, further comprising a fan for cooling the base.

19. The light source of claim 11, further comprising a mirror coupled to the second end of the rod to reflect the second light towards the first end of the rod.

20. The light source of claim 19, further comprising a spring which resiliently holds the mirror against the second end of the rod to accommodate thermal expansion of the rod.