Extensible linear light emitting diode illumination source

• US 6,880,952 B2
• Filed: 03/18/2003
• Issued: 04/19/2005
• Est. Priority Date: 03/18/2002
• Status: Active Grant

• Current Assignee: Wintriss Engineering Corporation
• Original Assignee: Wintriss Engineering Corporation
• Inventors: Henke, Gene, Kiraly, Chris
• Primary Examiner(s): Sember, Thomas M.
• Assistant Examiner(s): Choi, Jacob Y.
• Application Number:
  US10/391,888
• Publication Number:
  US 20030174517A1
• Time in Patent Office: 763 Days
• Field of Search: 362/545, 362/241, 362/247, 362/294, 362/373, 362/218, 362/219, 362/221, 362/223, 362/800, 362/11, 362/267, 348/131, 382/141
• US Class Current: 362/218
• CPC Class Codes: F21S 4/28 rigid, e.g. LED bars
• CPC Class Codes: F21V 15/013 the housing being an extrusion
• CPC Class Codes: F21V 15/015 Devices for covering joints between adjacent lighting devices; End coverings
• CPC Class Codes: F21V 29/70 characterised by passive heat-dissipating elements, e.g. heat-sinks
• CPC Class Codes: F21V 29/74 with fins or blades
• CPC Class Codes: F21W 2131/403 for machines
• CPC Class Codes: F21Y 2115/10 Light-emitting diodes [LED]
• CPC Class Codes: G01N 21/8806 Specially adapted optical and illumination features
• CPC Class Codes: Y10S 362/80 Light emitting diode

Abstract

A compact, energy-efficient extensible illumination source combines the reliability advantages of light emitting diodes (LEDs) with the brightness of conventional lighting. High reliability of the LEDs provides trouble-free operation over a long hour lifetime. This high-output light source can be used in direct lighting applications or for backlighting for translucent materials. The illumination source includes LED printed wire board segments that may be configured to form a light line of any length. The segments are mounted on a inner mounting base which also serves as a first stage heat sink for the LEDs. The illumination source includes a linear mirror for reflecting radiant energy away from the LEDs to produce a uniform linear illumination pattern. A window provides mechanical protection for the LEDs and may be used for diffusing or filtering light from the LEDs. An integral base in contact with the inner mounting base also serves as a heat sink and provides structural support for the illumination source. The integral base further includes channels and cavities for cooling the illumination source and for housing power cables.

Claims

1. An illumination source for illuminating a target, comprising:

an elongate mounting base having opposite first and second surfaces and a heat sink extending along the length of the mountain base;

at least one right printed wire board segment;

at least one left printed wire board segment separate from said right printed wire board segment;

a plurality of LEDs mounted at equally spaced intervals along said heat sink whereby heat transfer is provided from the LEDs to the mounting base, each LED of the plurality having a cathode lead attached to one of the at least one right printed wire board segment and the at least one left printed wire board segment, and each LED of the plurality having an anode lead attached to the other of the at least one right printed wire board segment and the at least one left printed wire board segment;

a support base attachable to the second surface of the mounting base, the support base having a first length, the base constructed from a heat transferring material, the support base comprising a plurality of interior channels extending the first length;

at least two support members attached to the first surface of the mounting base such that the plurality of LEDs are located therebetween, each of the at least two support members comprising a mirrored surface adjacent the plurality of LEDs for directing illumination produced by the plurality of LEDs towards the target;

a window attached to the at least two support members;

at least two brackets having the first length for enclosing the mounting base, the at least two support members, and at least a portion of the window; and

at least two end caps for enclosing a first and second end of each of the at least two brackets.

2. The illumination source of claim 1, wherein at least one of the plurality of interior channels is utilized for cooling the illumination source.

3. The illumination source of claim 1, wherein the at least one of the plurality of channels is utilized for housing electrical wires, the electrical wires supplying power to the plurality of LEDs.

4. The illumination source of claim 1, wherein the at least one right printed wire board segment comprises a plurality of right printed wire board segments connected end-to-end, and the at least one left printed wire board segment comprises a plurality of left printed wire board segments connected end-to-end.

5. The illumination source of claim 1, wherein each of the mirrored surfaces of the at least two support members is angled to direct light from the plurality of LEDs in a first manner.

6. The illumination source of claim 1, wherein each of the at least one right and left printed wire board segments comprises a plurality of equidistantly-spaced lead pads for accepting the anode and cathode leads of the plurality of LEDs, wherein the illumination produced by the equidistantly-spaced LEDs is uniform over the target.

7. The illumination source of claim 1, wherein the equidistantly-spaced lead pads are connected in a parallel series configuration.

8. A method of illuminating a target having a width with a uniform illumination across the width of the target, the method comprising the steps of:

mounting a right printed wire board segment and a left printed wire board segment on opposite sides of a heat sink on a mounting base;

mounting a plurality of LEDs at equally spaced intervals along said heat sink, said LEDs having first and second leads to the right and left printed wire board segments, wherein the first lead of each LED of the plurality of LEDs is connected to one of the right and left printed wire board segments, and the second lead of each LED of the plurality of LEDs is connected to the other one of the right and left printed wire board segments;

adhering the plurality of LEDs to the heat sink of the mounting base;

attaching at least two window support means to the inner PWB mounting base, wherein the plurality of LEDs are positioned between the at least two window support means;

attaching a window to the at least two window support means, the window positioned so that illumination from the LEDs passes through the window;

mounting the mounting base to a support base; and

enclosing the mounting base, the at least two window support means, and at least a portion of the window utilizing at least to two brackets.

9. The method of claim 8, further comprising the step of connecting the plurality of LEDs in a parallel series configuration.

10. The method of claim 8, further comprising the steps of:

providing at least one cooling channel in the support base; and

introducing a cooling means into the at least one cooling channel.

11. The method of claim 8, further comprising the step of extending the width of the illumination source by providing a plurality of right and left printed wire board segments joined end to end.

12. The method of claim 8, further comprising the step of finishing a surface of each of the at least two window support means adjacent the plurality of LEDs, the finished surfaces for reflecting illumination from the plurality of LEDs through the window.

13. A web inspection system for detecting defects of a web having a width, the web inspection system comprising:

a plurality of smart cameras for taking images of the web along the width, and for producing defect information;

a computer coupled to the plurality of smart cameras for processing the defect information; and

an illumination source for illuminating the web along the width, the illumination source comprising;

an elongate mounting base having a first surface, a second surface, and a longitudinally extending heat sink on said mountain base;

at least one right printed wire board segment mounted on said first surface to extend on one side of said heat sink and at least one left printed wire board segment mounted on said first surface to extend on the opposite side of said heat sink;

a plurality of LEDs mounted at spaced intervals along said heat sink and attached to the at least one right printed wire board segment and the at least one left PWB printed wire board segment for producing illumination;

a support bass attachable to the second surface of the mounting base arid having a first length, the base constructed from a heat transferring material, the support base having a plurality of interior channels extending the first length;

at least two support members attached to a second surface of the mounting base such that the plurality of LEDs are located therebetween, each of the at least two support members comprising a mirrored surface adjacent the plurality of LEDs for directing illumination produced by the LEDs towards the web;

a window attached to the at least two support members; and

a housing for enclosing the illumination source, the housing having an open portion aligned with the window for allowing the illumination to be directed towards the web.

14. The web inspection system of claim 13, wherein said LEDs are adhered directly to said heat sink for providing heat transfer from the plurality of LEDs.

15. The web inspection system of claim 13, wherein the housing comprises:

at least two brackets having the first length for enclosing the mounting base, the at least two support members, and at least a portion of the window; and

at least two end caps for enclosing first and second ends of the at least two brackets.

16. The web inspection system of claim 13, wherein the plurality of LEDs are attached to the at least one right printed wire board segment and the at least one left printed wire board segment in a parallel series configuration.

17. A linear, modular illumination system for uniform illumination of a target, comprising:

an elongate base support member having a plurality of interior channels extending along its length, the support member having a mounting surface;

at least one lighting segment secured to the mounting surface, the lighting segment comprising an elongate printed wiring board base having a right printed wiring board segment and a left printed wiring board segment, and a plurality of light sources mounted at spaced intervals along the base between the left and right wiring board segments, the light sources being attached to the right and left printed wiring board segments for producing illumination;

at least one of the channels in the base comprising a cooling channel;

a cooling fluid supply connected to said cooling channel to circulate cooling fluid in said channel and cool said light sources;

reflecting means associated with said lighting segment for directing illumination produced by the light sources onto a target; and

a housing enclosing the lighting segment and reflecting means, the housing having a window for transmitting illumination from the housing.

18. The system as claimed in claim 17, wherein a plurality of lighting segments are secured end-to-end along said mounting surface of said base support member, the light sources being equally spaced along the entire length of the plurality of lighting segments to produce uniform illumination.

19. The system as claimed in claim 17, further comprising a mounting member with a raised heat sink portion extending along the length of the mounting member and channels running along opposite right and left sides of the heat sink portion, the right printed wiring board segment being seated in the right side channel, the left printed wiring board segment being seated in the left side channel, and the light sources being mounted directly on the raised heat sink portion between the printed writing board segments, whereby heat is dissipated from said right sources by said heat sink portion.

20. The system as claimed in claim 19, wherein the light sources comprise LEDs and the LEDs are secured to the heat sink portion with a heat conducting adhesive.

21. The apparatus as claimed in claim 17, wherein each printed wiring board segment has a first end and a second end, and a plurality of lead pads at equally spaced intervals along the length of the segment, the first lead pad of each segment being at a first spacing from the first end of the segment and the last lead pad of each segment being at a second spacing from the second end of the segment, the first spacing and the second spacing together being equal to the spacing between adjacent lead pads along the segment, whereby the spacing between adjacent end lead pads of two segments when segments are secured together end-to-end is equal to the pad spacing along the length of each segment.