Fiber optic backlighting panel and dot process for making same

• US 5,226,105 A
• Filed: 06/27/1991
• Issued: 07/06/1993
• Est. Priority Date: 06/27/1991
• Status: Expired due to Term

• Current Assignee: Lumitex Incorporated
• Original Assignee: Poly-Optical Products Incorporated (RSL Fiber Systems, LLC)
• Inventors: Myers, J. Michael
• Primary Examiner(s): Ullah, Akm E.
• Application Number:
  US07/722,757
• Time in Patent Office: 740 Days
• Field of Search: 350/96.10, 350/96.15, 350/96.24, 362/26, 362/27, 362/31, 362/32, 362/330, 362/806, 358/901, 385/115, 385/120, 385/147, 385/901
• US Class Current: 385/147
• CPC Class Codes: G02B 6/001 the light being emitted along at least a portion of the lateral surface of the fibre
• CPC Class Codes: G02F 1/133524 Light-guides, e.g. fibre-optic bundles, louvered or jalousie light-guides
• CPC Class Codes: G09F 13/0409 Arrangements for homogeneous illumination of the display surface, e.g. using a layer having a non-uniform transparency arrangements of reflectors G09F13/14
• CPC Class Codes: Y10S 385/901 Illuminating or display apparatus

Abstract

An improved fiber optic backlighting panel provides increased background illumination relative to the amount of light transmitted therethrough, in devices such as rubber keypads, membrane switches, liquid crystal displays, rigid panels or the like. The fiber optic panel comprises a light source and a layer of optical fibers arranged adjacent each other which transmit the light beamed therein to different locations throughout the device, to provide increased and uniform intensity of light at specific locations or uniformly distributed light throughout the device. The optical fibers are selectively terminated at the different locations by forming holes through the layer of optical fibers with a laser, according to a predetermined geometric pattern of dot locations stored in a computer memory. In one specific embodiment for application in liquid crystal displays, a layer of foam is used to diffuse and scatter light to provide uniform illumination.

Claims

1. A method for making a flexible fiber optic backlighting panel to provide substantially uniform and increased background illumination of a surface comprising the steps of:

providing one, flexible layer of optical fibers, said optical fibers arranged in proximity to each other; and

cutting through selected optical fibers to form holes therein corresponding to a predetermined pattern of locations so that each of said optical fibers is cut only once.

2. The method of claim 1, further comprising the step of:

providing a reflective backing; and

adhering said layer of optical fibers to said reflective backing.

3. The method of claim 1, further comprising the step of:

defining said predetermined pattern of locations in accordance with the equation;

space="preserve" listing-type="equation">S=√

(d*A)/x

where;

S=the spacing between the locations in the X and Y directions;

X=the dimension of the panel in the X direction;

d=the fiber diameter; and

A=the panel surface area.

4. The method of claim 1, further comprising the step of:

forming holes according to said locations at specific locations on said layer of optical fibers, each hole corresponding to a respective one of a plurality of locations on said surface to provide uniform intensity of illumination at each location.

5. The method of claim 1, further comprising the step of:

forming evenly spaced holes according to said locations evenly spaced on said layer of optical fibers, each hole corresponding to a respective one of a plurality of locations on said surface to provide uniform illumination of the surface.

6. The method of claim 5, further comprising the step of:

defining said evenly spaced locations in accordance with the equation;

space="preserve" listing-type="equation">S=√

(d*A)/x

where;

S=the spacing between the locations in the X and Y directions;

X=the dimension of the panel in the X direction;

d=the fiber diameter; and

A=the panel surface area.

7. The method of claim 5, further comprising the step of:

placing a layer of diffusing material over said layer of optical fibers to diffuse the light.

8. The method of claim 1, further comprising the step of:

winding a single optical fiber in consecutive turns to form said layer of optical fibers; and

arranging said optical fibers adjacent each other without any overlapping of said optical fibers.

9. A method for making a fiber optic backlighting panel as defined in claim 1, wherein each of said optical fibers is fully cut only once.

10. The method of claim 1 further comprising positioning a plurality of layers on top of each other.

11. The method of claim 1 further comprising providing said one layer of uniform thickness.

12. The method of claim 1 further comprising:

forming one end of the layer into a bundle remote from the panel.

13. A method for providing substantially uniform and increased background illumination of a surface comprising the steps of:

providing one, flexible layer of optical fibers; and

selectively terminating various optical fibers in said layer by fully or partially cutting holes through said various optical fibers at a predetermined location on the surface corresponding to a predetermined pattern of locations.

14. A method for providing uniform and increased background illumination of a surface as defined in claim 13, additionally comprising the step of:

beaming light from a light source through said layer of optical fibers to a plurality of different locations on the surface, said holes enabling the light conducted by each optical fiber to exit therefrom and focus all the intensity of said light directly at a respective one of said plurality of locations on the surface.

15. A method for making a fiber optic backlighting panel to provide uniform and increased background illumination of a surface comprising the steps of:

providing a winding drum having a plurality of pegs disposed about peripheral ends thereof;

wrapping an optical fiber around said winding drum in consecutive turns and forming a layer of optical fibers;

positioning strips of reflective material upon said winding drum by placing registration holes formed therein over said pegs;

removing said strips of reflective material from said pegs;

cutting said layer of optical fibers between said registration holes; and

aligning each strip with said registration holes and directing a laser beam over said strip to penetrate through said optical fibers and form holes according to a predetermined geometric pattern of dot locations.

16. A method for making a fiber optic backlighting panel to provide uniform and increased background illumination of a surface as defined in claim 15, further comprising the step of:

laminating a sheet of clear plastic over said layer of optical fibers.

17. A method for making a fiber optic backlighting panel to provide uniform and increased background illumination of a surface as defined in claim 16, wherein said laminating step comprises:

laminating a sheet of Mylar®

over said layer of optical fibers.

18. An improved fiber optic panel for providing background illumination of a surface, comprising:

one, flexible layer of optical fibers for transmitting light to a plurality of different locations on the surface, said optical fibers having holes cut therethrough according to a predetermined pattern of locations, said, holes selectively terminating each optical fiber directly adjacent a respective one of said different locations and no optical fiber being cut more than once.

19. An improved fiber optic panel for providing background illumination of a surface as defined in claim 18, wherein said holes selectively terminate said optical fibers at evenly spaced locations providing uniform illumination throughout the surface.

20. An improved fiber optic panel for providing background illumination of a surface as defined in claim 19, wherein said evenly spaced locations are defined by the equation:

space="preserve" listing-type="equation">S=√

(d*A)/x

where;

S=the spacing between the dots in the X and Y directions;

X=the dimension of the panel in the X direction;

d=the fiber diameter; and

A=the panel surface area.

21. An improved fiber optic panel for providing background illumination of a surface as defined in claim 18, further comprising:

means for diffusing disposed over said holes to diffuse the light to provide uniform illumination throughout the surface.

22. An improved fiber optic panel for providing background illumination of a surface as defined in claim 21, wherein said diffusing means is at least one layer of light diffusing material.

23. An improved fiber optic panel for providing background illumination of a surface as defined in claim 18, wherein said layer of optical fibers is adhered to a reflective backing.

24. An improved fiber optic panel providing background illumination of a surface as defined in claim 18, wherein no optical fiber is fully cut more than once.

25. A method for making a fiber optic backlighting panel to provide uniform and increased background illumination of a surface comprising the steps of:

providing one flexible layer of optical fibers, said optical fibers arranged in intimate proximity to each other; and

cutting through selected optical fibers to form holes therein corresponding to a predetermined pattern of locations so that each of said optical fibers has only one fully or partially cut hole.

26. An improved fiber optic panel for providing background illumination of a surface, comprising:

one, flexible layer of optical fibers for transmitting light to a plurality of different locations on the surface, said optical fibers having holes fully or partially cut therethrough according to a predetermined pattern of locations, said holes selectively terminating each optical fiber directly adjacent a respective one of said different surface locations.

27. A method of providing substantially uniform and increased background illumination comprising the steps of:

providing at least one layer of optical fibers; and

selectively terminating various of the fibers in each of said at least one layers to provide a two-dimensional pattern of illumination in each of at least one layers.

28. An improved fiber optic panel for providing background illumination of a surface, comprising:

at least one layer of optical fibers, selected fibers of each of said at least one layers being terminated in a two-dimensional pattern to provide an area of illumination in each of said at least one layers.

29. A method for making a flexible fiber optic backlighting panel to provide substantially uniform and increased background illumination of a surface comprising the steps of:

providing at least one layer of optical fibers, said optical fibers arranged in proximity to each other;

cutting through selected optical fibers with a laser beam to form holes therein corresponding to a predetermined pattern of locations so that each of said optical fibers is cut only once;

providing a reflective backing; and

adhering said layer of optical fibers to said reflective backing.

30. A method for providing substantially uniform and increased background illumination of a surface comprising the steps of:

providing a layer of optical fibers; and

selectively terminating various optical fibers in said layer by fully or partially cutting holes through said various optical fibers with a laser bean at a predetermined location on the surface corresponding to a predetermined pattern of locations.

31. An improved fiber optic panel for providing background illumination of a surface, comprising:

a layer of optical fibers for transmitting light to a plurality of different locations on the surface, said optical fibers having holes cut therethrough with a laser beam according to a predetermined pattern of locations, said holes selectively terminating each optical fiber directly adjacent a respective one of said different locations and no optical fiber being cut more than once.

32. A method for making a fiber optic backlighting panel to provide uniform and increased background illumination of a surface comprising the steps of:

providing at least one layer of optical fibers, said optical fibers arranged in intimate proximity to each other; and

cutting through selected optical fibers with a laser beam to form holes therein corresponding to a predetermined pattern of locations so that each of said optical fibers has only one fully or partially cut hole.

33. An improved fiber optic panel for providing background illumination of a surface, comprising:

a layer of optical fibers for transmitting light to a plurality of different locations on the surface, said optical fibers having holes fully or partially cut therethrough with a laser beam according to a predetermined pattern of locations, said holes selectively terminating each optical fiber directly adjacent a respective one of said different surface locations.

34. A method for making a fiber optic backlighting panel to provide substantially uniform and increased background illumination of a surface comprising the steps of:

providing at least one layer of optical fibers, said optical fibers arranged in proximity to each other;

cutting through selected optical fibers to form holes therein corresponding to a predetermined pattern of locations so that each of said optical fibers is cut only once; and

defining said predetermined pattern of locations in accordance with the equation;

space="preserve" listing-type="equation">S=√

(d*A)/x

where;

S=the spacing between the locations in the X and Y directions;

X=the dimension of the panel in the X direction;

d=the fiber diameter; and

A=the panel surface area.

35. A method for making fiber optic backlighting panel to provide substantially uniform and increased background illumination of a surface comprising the steps of:

providing at lest one layer of optical fibers, said optical fibers arranged in proximity to each other;

cutting through selected optical fibers to form holes therein corresponding to a predetermined pattern of locations so that each of said optical fibers is cut only once;

forming evenly spaced holes according to said locations evenly spaced on said layer of optical fibers, each hole corresponding to a respective one of a plurality of locations on said surface to provide uniform illumination of the surface; and

defining said evenly spaced locations in accordance with the equation;

space="preserve" listing-type="equation">S=√

(d*A)/x

where;

S=the spacing between the locations in the X and Y directions;

X=the dimension of the panel in the X direction;

d=the fiber diameter; and

A=the panel surface area.

36. A method for making a fiber optic backlighting panel to provide substantially uniform and increased background illumination of a surface comprising the steps of:

providing at least one layer of optical fibers, said optical fibers arranged in proximity to each other;

cutting through selected optical fibers to form holes therein corresponding to a predetermined pattern of locations so that each of said optical fibers is cut only once;

winding a single optical fiber in consecutive turns to form said layer of optical fibers; and

arranging said optical fibers adjacent each other without any overlapping of said optical fibers.

37. An improved fiber optic panel for providing background illumination of a surface, comprising:

a layer of optical fibers for transmitting light to a plurality of different locations on the surface, said optical fibers having holes cut therethrough according to a predetermined pattern of locations, said holes selectively terminating each optical fiber directly adjacent a respective one of said different locations and no optical fiber being cut more than once wherein said holes selectively terminate said optical fibers at evenly spaced locations providing uniform illumination throughout the surface; and

wherein said evenly spaced locations are defined by the equation;

space="preserve" listing-type="equation">S=√

(d*A)/x

where;

S=the spacing between the locations in the X and Y directions;

X=the dimension of the panel in the X direction;

d=the fiber diameter; and

A=the panel surface area.