Light source

• US 5,128,846 A
• Filed: 10/23/1990
• Issued: 07/07/1992
• Est. Priority Date: 10/23/1990
• Status: Expired due to Fees

• Current Assignee: International Business Machines Corporation
• Original Assignee: International Business Machines Corporation
• Inventors: Ries, Michael D., Mills, Ross N., Reeves-Janzen, Cynthia F., Scott, John C.
• Primary Examiner(s): Husar, Stephen F.
• Application Number:
  US07/602,036
• Time in Patent Office: 623 Days
• Field of Search: 362/16, 362/31, 362/84, 362/89, 362/223, 362/224, 362/253, 362/260, 362/307, 362/310, 362/308, 362/329, 362/32, 362/26
• US Class Current: 362/224
• CPC Class Codes: F21V 2200/30 of light guides doped with fluorescent agents
• CPC Class Codes: F21V 9/08 for producing coloured light, e.g. monochromatic; for reducing intensity of light with provision for controlling the colour F21V9/40
• 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 6/4298 coupling with non-coherent light sources and/or radiation detectors, e.g. lamps, incandescent bulbs, scintillation chambers
• CPC Class Codes: G03B 27/542 for copying cameras, reflex exposure lighting
• CPC Class Codes: G03G 15/04045 for exposing image information provided otherwise than by directly projecting the original image onto the photoconductive recording material, e.g. digital copiers G03G15/041, G03G15/043 take precedence
• CPC Class Codes: G03G 15/169 with means for preconditioning the toner image before the transfer G03G15/095 and G03G15/11 take precedence
• CPC Class Codes: G03G 21/08 using optical radiation
• CPC Class Codes: H04N 1/02815 Means for illuminating the original, not specific to a particular type of pick-up head
• CPC Class Codes: H04N 1/0285 in combination with at least one reflector which is in fixed relation to the light source
• CPC Class Codes: H04N 1/02855 in combination with a light guide, e.g. optical fibre, glass plate light-guides per se G02B6/00
• CPC Class Codes: H04N 1/0287 using a tubular lamp or a combination of such lamps

Abstract

A fluorescent dyed polymer member and a light source are structurally arranged in a manner to efficiently gather light from the light source and then transmit the gathered light to a light utilization device. Light from the light source is gathered over a large area that is occupied by the polymer member. This gathered light is transmitted through the polymer member to an edge portion thereof having a relatively small light emitting area. Light is then emitted as an external beam having a cross section that corresponds to the physical shape of the edge of the polymer member, for example a straight of linear footprint of light. The area brightness of this external beam is greater than the area brightness of the initial light source.

Claims

1. A linear light source, comprising,

an elongated light source providing a radiation pattern in the form of an elongated cylinder, and

a fluorescent-dyed polymeric sheet wrapped to form a hollow, elongated, cylindrical tube about said light source generally equal in length to said radiation pattern, said polymeric sheet generally enclosing said light source, and having an exposed linear edge,

said polymeric sheet containing a fluorescent dye that is responsive to radiation from said light source, said fluorescent dye responding to radiation from said light source and operating to generate fluorescent light within said polymeric sheet, and said fluorescent light being transmitted through said polymeric sheet to said linear edge, whereat said fluorescent light exits said polymeric sheet as a line of light.

2. The light source of claim 1 wherein said exposed linear edge is formed to be relatively thick, so as to render said exposed linear edge self supporting, and wherein a tapered end is provided on said exposed linear edge, so as to form said line of light to a desired thickness.

3. The light source of claim 1 wherein said polymeric tube is substantially transparent to said radiation from said light source, and including a tubular mirror surrounding said polymeric tube and operating to redirect any radiation from said light source back into said polymeric tube.

4. The light source of claim 1 including a plurality of said elongated light sources, each of said light sources having a fluorescent-dyed polymeric sheet that is wrapped to form a hollow, elongated, cylindrical tube about said light source, and said plurality of fluorescent-dyed polymeric sheets having one common exposed linear edge.

5. The light source of claim 4 wherein said common exposed linear edge is formed to be relatively thick, and wherein a tapered end is provided on said common linear edge.

6. The light source of claim 5 wherein each of said plurality of polymeric tubes is substantially transparent to said radiation from said light source, and including a tubular mirror surrounding said each of said plurality of polymeric tubes and operating to redirect any radiation from said light source back into its associated polymeric tube.

7. The light source of claim 1 including:

a plurality of fluorescent-dyed polymeric sheets concentrically wrapped to form a plurality of hollow, elongated, cylindrical tubes about said light source,

each of said polymeric sheets containing a different dyestuff so as to generate a different colored fluorescent light within each of said polymeric sheets, and

said fluorescent light within each of said plurality of polymeric sheets being transmitted therethrough to a linear edge thereof, whereat fluorescent light exits said plurality of polymeric sheets as a plurality of lines of light of different color.

8. The light source of claim 7 wherein the linear edge of each of said plurality of polymeric sheets is formed to be relatively thick, so as render said linear edge self supporting, and wherein a tapered end is provided on each of said linear edges, so as to form said plurality of lines of light to a desired shape.

9. The light source of claim 6 wherein said plurality of polymeric tubes are substantially transparent to said radiation from said light source, and including a tubular mirror surrounding said plurality of polymeric tubes and operating to redirect any radiation from said light source back into said polymeric tubes.

10. In combination;

a light source providing light radiation of a first spectral characteristic, and in a pattern that generally surrounds said light source, and

a polymeric sheet wrapped to surround said light source, said polymeric sheet having an externally exposed edge portion,

said polymeric sheet containing a radiation sensitive material that responds to said radiation of said first spectral characteristic and operates to generate light radiation of a second spectral characteristic within said polymeric sheet, and said generated light of said second spectral characteristic being transmitted to said edge portion, whereat said generated light of said second spectral characteristic exits said polymeric sheet as a beam whose cross section conforms to the shape of said edge portion.

11. The combination of claim 10 wherein said material comprises a dye that is responsive to said radiation of said first characteristic.

12. The combination of claim 11 wherein said light source comprises an elongated and substantially linear light source providing a cylinder of light radiation of said first spectral characteristic, and wherein said polymeric sheet is wrapped to form a hollow tube about said light source, said tube including an extending edge portion operating to form a beam whose cross section is substantially rectangular.

13. The combination of claim 12 wherein said extending edge portion is tapered so as to shape said beam to a desired cross section.

14. The combination of claim 10 including a plurality of said light sources, each of which is surrounded by one of a like plurality of polymeric sheets, and a common extending edge portion for all of said plurality of polymeric sheets.

15. The combination of claim 13 wherein said plurality of polymeric sheets and said common extending edge portion are formed as a unitary molded assembly.

16. The combination of claim 15 wherein said common extending edge portion is tapered in a manner to shape said beam to a desired cross section.

17. The combination of claim 10 further including:

a linear array shutter means located adjacent said externally exposed edge portion for receiving and selectively transmitting said generated light of said second spectral characteristic,

a rod lens array means located adjacent said linear array shutter for receiving and transmitting said generated light selectively transmitted from said linear array shutter, and

a photoconductor means located adjacent said rod lens array for receiving said generated light transmitted from said rod lens array.

18. The combination of claim 17 wherein said material comprises a dye that is responsive to said radiation of said first characteristic.

19. The combination of claim 18 wherein said light source comprises an elongated and substantially linear light source providing a cylinder of light radiation of said first spectral characteristic, and wherein said polymeric sheet is wrapped to form a hollow tube about said light source, said tube including an extending edge portion operating to form a beam whose cross section is substantially rectangular.

20. The combination of claim 19 wherein said extending edge portion is tapered so as to shape said beam to a desired cross section.

21. The combination of claim 19 wherein said polymeric sheet comprises a unitary molded member.

22. A method for providing a light beam to a utilization device that requires a beam intensity of at least N light units per given beam area, comprising the steps of;

providing low intensity light source means for emitting light over a relatively large area, the intensity of said emitted light over said relatively large area being less than said N light units per given area,

providing a polymer member structurally arranged with said light source means to occupy said relatively large area in a manner to gather substantially all of the light that is emitted by said light source means, said polymer member having an exposed edge portion,

tapering said exposed edge portion in a manner to provide an external beam having a beam intensity that is equal to at least N light units per given beam area, and

transmitting said gathered light through said polymer member to said exposed edge portion, whereat light is emitted as an external beam having a cross section that corresponds to the physical shape of said exposed edge portion, said external beam having a beam intensity that is equal to at least N light units per given beam area.

23. The method of claim 22 wherein said utilization device also requires a beam of a given spectral characteristic, including the steps of;

providing said low intensity light source means as a light source means whose emitted light is of a spectral characteristic that is different from said given spectral characteristic, and

providing said polymer member as a fluorescent dyed polymer member that is operable to absorb said emitted light of said different spectral characteristic, and operates to transform said light of said different spectral characteristic into light of said given spectral characteristic.

24. The method of claim 23 including the step of tapering said exposed edge portion in a manner to provide an external beam of a desired cross sectional shape and is of a beam intensity that is equal to at least N light units per given beam area.

25. A unit area light amplifier, comprising;

light source means operable to emit a surface of light having a given light intensity per unit area of said surface,

fluorescent dyed polymer means arranged to encircle said light source means, to thereby receive substantially all of the light within said surface of light,

edge means formed as portion of said polymer means, said edge means having a cross sectional area that is less than the area of said surface of light, and

wherein said light source means comprises a linear lamp, wherein said surface of light comprises a cylindrical surface of light surrounding said lamp, said cylindrical surface of light having an axis corresponding generally to the position of said lamp, and wherein said polymer means comprises a hollow cylinder surrounding said lamp, said hollow polymer cylinder having an axis corresponding generally to the position of said lamp, and said hollow polymeric cylinder having at least one exposed edge portion comprising said edge means.

26. The light amplifier of claim 25 including a plurality of individual edges extending from said cylinder, said plurality of individual edges having an aggregate cross sectional area that is less than the area of said surface of light.

27. The light amplifier of claim 26 wherein said hollow polymeric cylinder comprises a unitary molded member.

28. The light amplifier of claim 26 wherein said plurality of individual edges comprise generally parallel edges that extend generally parallel to the axis of said polymer cylinder, and including a loop photoconductor surrounding said polymer means and having a like plurality of light sensitive operating stations located to correspond to the positions of said plurality of individual edges.

29. The light amplifier of claim 28 wherein said plurality of light sensitive operating stations include a photoconductor preclean station, a photoconductor imaging station, and a photoconductor pretransfer station.

30. The unit area light sources, of claim 25 further including:

a plurality of linear light sources, each of said light sources having a central axis, said plurality of light sources being mounted with the plurality of central axes thereof arranged to be mutually parallel, and said plurality of central axes occupying a cylindrical volume having a central axis,

a like plurality of fluorescent dyed polymeric sheets, each sheet of which is located between two adjacent ones of said plurality light sources, so as to receive light from said adjacent light sources,

each of said plurality of polymeric sheets including a linear extending edge portion extending parallel to the central axis of said cylindrical volume, said plurality of edge portions being positioned such that if said plurality of edge portions where extended said plurality of edge portions would meet at the central axis of said cylindrical volume, and

light gathering means positioned at said central axis of said cylindrical volume, the light gathering means being operable to gather light emitted by said plurality of edge portions.

31. The unit area light amplifier of claim 30 wherein said each of said polymeric sheets is configured to substantially encircle said adjacent ones of said light sources as to receive substantially all of the light that is emitted from said adjacent light sources.

32. In combination;

a plurality of linear light sources, each of said light sources having a central axis, said plurality of light sources being mounted with the plurality of central axes thereof arranged to be mutually parallel, and said plurality of central axes occupying a cylindrical volume having a central axis,

a like plurality of fluorescent dyed polymeric sheets, each sheet of which is located between two adjacent ones of said plurality light sources, so as to receive light from said adjacent light sources,

each of said plurality of polymeric sheets including a linear extending edge portion extending parallel to the central axis of said cylindrical volume, said plurality of edge portions being positioned such that if said plurality of edge portions were extended said plurality of edge portions would meet at the central axis of said cylindrical volume, and

light gathering means positioned at said central axis of said cylindrical volume, the light gathering means being operable to gather light emitted by said plurality of edge portions.

33. The combination of claim 32 wherein said each of said polymeric sheets is configured to substantially encircle said adjacent ones of said light sources, so as to receive substantially all of the light that is emitted from said adjacent light sources.