LED-based dental exam lamp with variable chromaticity

Abstract

An electrically powered light source including a light emitting diode (LED) having variable chromaticity, which is adapted for use in a dental operatory. A dental operatory lamp includes a thermally conductive housing having a front directed toward the operating area and a rear away from the operating area; a generally elliptical reflector located on the rear of the thermally conductive housing; at least one heat pipe; a plurality of color LEDs projecting light toward the elliptical reflector, the plurality of LEDs being in thermal contact with the at least one heat pipe; and an optical light guide for combining light from said LEDs. Another embodiment of the lamp includes at least two user selectable light spectra, one of said spectra providing white light with color temperature in the range 4000° K-6000° K and one spectra having reduced output in the wavelength range 400-500 nm.

What is claimed is: 
     
       1. A dental operatory lamp used to illuminate an operating area comprising: a plurality of color LEDs; an optical light guide for combining light from said LEDs; and at least two user selectable light spectra, one of said spectra providing white light with color temperature in the range 4000° K-6000° K and one spectra having reduced output in the wavelength range 400-500 nm. 
     
     
       2. The dental operatory lamp of  claim 1 , wherein the user selectable light spectra comprises varying ratios of at least three colors emanating from the color LEDs. 
     
     
       3. The dental operatory lamp of  claim 1 , wherein the user selectable light spectra comprises various ratios of red, blue, green, and amber light emanating from the color LEDs. 
     
     
       4. A dental operatory lamp used to illuminate an operating area comprising: a housing having a front directed toward the operating area and a rear away from the operating area; a reflector module located at the rear of the housing; a plurality of color light emitting diodes (LEDs) on the reflector module; and an optical light guide configured to direct the light from the color LEDs toward the front of the lamp in a pattern that focuses white light from the lamp to a central area of illumination of high intensity, with significantly reduced intensity illumination outside the central area; an attachment structure disposed on the housing; and a suspension structure connected to the attachment structure and arranged to suspend the lamp in a dental operatory. 
     
     
       5. The dental operatory lamp of  claim 4 , wherein the optical light guide produces at least three operating modes with different light characteristics. 
     
     
       6. The dental operatory lamp of  claim 4 , wherein the lamp produces white light with coordinated color temperatures of between 4000° K and 6000° K and maintaining a color rendering index in excess of 75. 
     
     
       7. The dental operatory lamp of  claim 4 , wherein the a user selectable light spectra comprises various ratios of red, blue, or green, or amber light emanating from the color LEDs. 
     
     
       8. A dental operatory lamp used to illuminate an operating area comprising: a housing having a front directed toward the operating area and a rear away from the operating area; a reflector module located in the housing; and a plurality of color light emitting diodes (LEDs) on the reflector module, wherein said lamp comprises different operating modes comprising a first operating mode having light characteristics for curing of a dental adhesive and a second operating mode having light characteristics that do not cure the dental adhesive. 
     
     
       9. The dental operatory lamp of  claim 8 , wherein said first operating mode comprises a cool white mode or a warm white mode. 
     
     
       10. The dental operatory lamp of  claim 9 , wherein said cool white mode comprises producing a light spectra in the range of 4000-6000 degrees K. 
     
     
       11. The dental operatory lamp of  claim 9 , wherein said warm white mode comprises producing a light spectra in the range of 4000-6000 degrees K. 
     
     
       12. The dental operatory lamp of  claim 9 , wherein said cool white mode and warm white mode comprise producing a light spectra with 70 or greater color rendering index. 
     
     
       13. The dental operatory lamp of  claim 8 , wherein said second operating mode comprises light having flux below 500 nm. 
     
     
       14. The dental operatory lamp of  claim 8 , further comprising a light guide for combining light from said LEDs. 
     
     
       15. The dental operatory lamp of  claim 14 , wherein said light guide is configured to direct light from said LEDs toward the front of said housing. 
     
     
       16. The dental operatory lamp of  claim 8 , wherein said plurality of color LEDs comprises LEDs that emit at least three colors. 
     
     
       17. The dental operatory lamp of  claim 16 , wherein said at least three colors comprises at least three of blue, green, amber, or red. 
     
     
       18. The dental operatory lamp of  claim 17 , wherein said at least three colors comprises blue, green, amber, and red. 
     
     
       19. The dental operatory lamp of  claim 8 , wherein said different operating modes comprise at least two user selectable light spectra, one of said spectra providing white light with color temperature in the range 4000° K-6000° K and one spectra having reduced output in the wavelength range 400-500 nm. 
     
     
       20. A dental examination lamp comprising:
 a housing;   a plurality of tubes within the housing and arranged in a generally side-by-side configuration, each tube having an interior, a first end, and a second end, the second end open to the transmission of light from the interior of the tube, each tube being absorptive, generally non-reflective, or both absorptive and generally non-reflective;   a plurality of light emitting diodes (LEDs), each of the LEDs being arranged to direct light through at least part of one of the tubes and out of the lamp   an attachment structure disposed on the housing; and   a suspension structure connected to the attachment structure and arranged to suspend the lamp in a dental operatory.   
     
     
       21. The lamp of claim 20, wherein the plurality of tubes are positioned with their longitudinal axes aligned to direct light toward predetermined points to form a predetermined light pattern within an examination area. 
     
     
       22. The lamp of claim 20, further comprising a plurality of lenses, with at least one lens per tube located proximate to the second end thereof and adapted to direct the light from the plurality of LEDs out of the lamp in a pattern that casts illumination over an examination area. 
     
     
       23. The lamp of claim 20, further comprising a lens member at a front of the lamp presenting a plurality of individual lens sections over a face thereof arranged in a pattern corresponding to the position of the plurality of tubes, each lens section being aligned with a respective tube and adapted to direct light from that tube out of the lamp in a pattern that casts illumination over an examination area. 
     
     
       24. The lamp of claim 20, further comprising a collimating element arranged to collimate light emanating from an LED. 
     
     
       25. The lamp of claim 20, further comprising a lens adapted to color the light directed out of the lamp. 
     
     
       26. The lamp of claim 20, wherein an interior surface of at least one of the plurality of tubes is black. 
     
     
       27. The lamp of claim 20, wherein the plurality of tubes includes at least five tubes. 
     
     
       28. The lamp of claim 20, wherein the plurality of tubes includes at least five columns of tubes. 
     
     
       29. The lamp of claim 20, wherein an interior surface of at least one of the plurality of tubes is absorptive. 
     
     
       30. The lamp of claim 20 wherein the light has reduced output at wavelengths that cure adhesives or composites. 
     
     
       31. A dental examination lamp comprising:
 a housing;   a plurality of stray light tubes within the housing, each of the plurality of stray light tubes adapted to reduce emission of stray light rays outside a target footprint;   a plurality of light emitting diodes (LEDs), at least one LED for each stray light tube, wherein the plurality of stray light tubes is arranged in a generally side-by-side configuration;   an attachment structure disposed on the housing; and   a suspension structure connected to the attachment structure and arranged to suspend the lamp in a dental operatory.   
     
     
       32. The lamp of claim 31, wherein at least one of the stray light tubes comprises an absorptive or generally non-reflective interior surface. 
     
     
       33. The lamp of claim 31, further comprising a collimating element arranged to collimate light emanating from at least one of the plurality of LEDs. 
     
     
       34. The lamp of claim 31, wherein the plurality of stray light tubes are positioned with their longitudinal axes aligned toward predetermined points to direct the light from the plurality of LEDs out of the lamp to form a predetermined light pattern within an examination area. 
     
     
       35. The lamp of claim 31, further comprising a plurality of lenses, each located at an end of a stray light tube, the plurality of lenses adapted to direct the light from the plurality of LEDs out of the lamp in a predetermined pattern that casts illumination over an examination area. 
     
     
       36. The lamp of claim 35, wherein the plurality of stray light tubes and the plurality of lenses form a plurality of assemblies, each assembly adapted to direct light passing through the assembly. 
     
     
       37. The lamp of claim 31, further comprising a lens adapted to color light emanating from at least one of the plurality of LEDs. 
     
     
       38. The lamp of claim 31, wherein an interior surface of at least one of the plurality of stray light tubes is black. 
     
     
       39. The lamp of claim 31, wherein the plurality of stray light tubes includes at least five tubes. 
     
     
       40. The lamp of claim 31, wherein the plurality of stray light tubes includes at least five columns of tubes. 
     
     
       41. A dental examination lamp, comprising:
 a housing;   a plurality of tubes mechanically coupled to the housing and arranged in a generally side-by-side configuration, each tube having an interior, a first end, and a second end, the second end of each tube being open to transmission of light from the interior of the tube, each tube being optically absorptive, generally non-reflective, or both optically absorptive and generally non-reflective;   a plurality of light emitting diodes (LEDs), each of the LEDs being arranged to direct light through at least part of one of the tubes and out of a front of the lamp;   an attachment structure disposed on the housing; and   a suspension structure connected to the attachment structure and arranged to suspend the lamp in a dental operatory.   
     
     
       42. The lamp of claim 41, further comprising a lens adapted to color light emanating from at least one of the plurality of LEDs. 
     
     
       43. The lamp of claim 41, wherein an interior surface of at least one of the plurality of tubes is black. 
     
     
       44. The lamp of claim 41, wherein the plurality of tubes includes at least five tubes. 
     
     
       45. The lamp of claim 41, wherein the plurality of tubes includes at least five columns of tubes. 
     
     
       46. A method of illuminating a dental operating area, the method comprising:
 providing a dental operatory lamp, the dental operatory lamp including
 a plurality of stray light tubes adapted to reduce emission of stray light rays outside a target footprint, the plurality of tubes arranged in a generally side-by-side configuration, and 
 at least one light emitting diode (LED) arranged to direct light through each stray light tube and out of the lamp; 
   providing an attachment structure disposed on the lamp;   providing a suspension structure connected to the attachment structure;   by the suspension structure, suspending the lamp in a dental operatory   generating light via each of the at least one LEDs; and   illuminating a patient's mouth with the light.   
     
     
       47. The method of claim 46 wherein providing the dental operatory lamp comprises providing a plurality of stray light tubes with an absorptive surface. 
     
     
       48. The method of claim 46, further comprising providing a collimating element to collimate light emanating from at least one of the plurality of LEDs. 
     
     
       49. The method of claim 46, further comprising providing the plurality of stray light tubes with their longitudinal axes aligned toward predetermined points to direct the light from the plurality of LEDs out of the lamp to form a predetermined light pattern within an examination area. 
     
     
       50. The method of claim 46, further comprising providing a plurality of lenses, each at an end of a stray light tube, the plurality of lenses adapted to direct the light from the plurality of LEDs out of the lamp in a predetermined pattern that casts illumination over an examination area. 
     
     
       51. The method of claim 50, further comprising providing a plurality of assemblies from the plurality of tubes and the plurality of lenses and dispersing light passing through each assembly. 
     
     
       52. The method of claim 46, further comprising modifying a color of light emanating from at least one of the plurality of LEDs via a lens. 
     
     
       53. The method of claim 46, wherein each of the plurality of tubes has an interior surface and the interior surface of at least one of the plurality of tubes is black. 
     
     
       54. The method of claim 46, wherein the plurality of tubes includes at least five tubes. 
     
     
       55. The method of claim 46, wherein the plurality of tubes includes at least five columns of tubes. 
     
     
       56. The method of claim 46 wherein providing the dental operatory lamp comprises providing a plurality of stray light tubes with a generally non-reflective surface. 
     
     
       57. The method of claim 46 wherein illuminating a patient's mouth comprises aiming the light at the patient's mouth while reducing stray light entering the patient's eyes. 
     
     
       58. The method of claim 46 wherein the illuminating step comprises illuminating the patient's mouth with light having reduced output at wavelengths that cure adhesives or composites. 
     
     
       59. The method of claim 46 wherein the illuminating step comprises selecting from a plurality of light spectra a light spectrum with reduced output at wavelengths that cure adhesives or composites.