U.S. patent application number 12/031740 was filed with the patent office on 2008-06-05 for flat optical fiber light emitters.
Invention is credited to David J. Page, Brian M. Spahnie.
Application Number | 20080130264 12/031740 |
Document ID | / |
Family ID | 35732311 |
Filed Date | 2008-06-05 |
United States Patent
Application |
20080130264 |
Kind Code |
A1 |
Page; David J. ; et
al. |
June 5, 2008 |
FLAT OPTICAL FIBER LIGHT EMITTERS
Abstract
Light emitters are made of one or more cladded flat optical
fibers having opposite flat sides and disruptions along at least a
portion of the length of the fibers to cause light entering at
least one end to be emitted from at least one side. The ends of the
flat optical fibers may have substantially the same thickness as a
light source and a width substantially equal to or substantially
greater than the width of the light source for ease of optically
coupling one or more such light sources to the flat optical fiber
ends.
Inventors: |
Page; David J.;
(Painesville, OH) ; Spahnie; Brian M.; (Brunswick,
OH) |
Correspondence
Address: |
RENNER OTTO BOISSELLE & SKLAR, LLP
1621 EUCLID AVENUE, NINETEENTH FLOOR
CLEVELAND
OH
44115
US
|
Family ID: |
35732311 |
Appl. No.: |
12/031740 |
Filed: |
February 15, 2008 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
10900000 |
Jul 27, 2004 |
|
|
|
12031740 |
|
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Current U.S.
Class: |
362/23.15 |
Current CPC
Class: |
G02B 6/002 20130101;
G02B 6/0021 20130101; G02B 6/0036 20130101; G02B 6/0073 20130101;
G02B 6/004 20130101; G02B 6/10 20130101 |
Class at
Publication: |
362/26 |
International
Class: |
G01D 11/28 20060101
G01D011/28 |
Claims
1. A light emitter comprising a plurality of flat optical fibers
each having opposite flat sides and opposite side edges and
opposite ends, the fibers being disposed in a common plane in
side-by-side relation to one another, at least one surface mount
light source optically coupled to an end of each of the fibers,
each light source having substantially the same thickness as each
of the fibers to which each light source is optically coupled, each
of the fibers having a light conducting core that is cladded by an
outer cladding to keep light in for conducting light entering the
end of the fibers, and disruptions along at least a portion of the
length of the fibers to cause conducted light to be emitted from at
least one side of each of the fibers.
2. The light emitter of claim 1 wherein a plurality of light
sources each having substantially the same thickness and
substantially less width than at least some of the fibers are
optically coupled to an end of at least some of the fibers in
side-by-side relation to one another across the width of at least
some of the fibers.
3. The light emitter of claim 1 wherein the disruptions are
deformities on or in both sides of each of the fibers.
4. The light emitter of claim 1 in combination with a keypad having
a plurality of rows of keys, the fibers having gaps between the
fibers corresponding to the spacing between the plurality of rows
of the keys so the fibers extend between the plurality of rows of
the keys, the fibers having disruptions in spaced apart portions of
their length corresponding to the spacing between at least some of
the keys in each row for backlighting at least some of the keys in
each row.
5. The light emitter of claim 1 wherein the end of at least one of
the fibers is lens shaped.
6. The light emitter of claim 5 wherein the end of the at least one
fiber is transversely rounded across the width of the fiber.
7. The light emitter of claim 1 wherein the end of at least one of
the fibers has a lens shape intermediate the width of the
fiber.
8. The light emitter of claim 7 wherein the lens shape is recessed
within the end of the at least one fiber.
9. The light emitter of claim 1 wherein a plurality of the fibers
are held together by an adhesive film.
10. The light emitter of claim 1 wherein a plurality of the fibers
are held together by mechanical clips or fasteners.
11. A light emitter comprising at least one flat optical fiber
having opposite flat sides and opposite side edges and opposite
ends, at least one surface mount light source having substantially
the same thickness as the fiber optically coupled to an end of the
fiber, the fiber having a light conducting core that is cladded by
an outer cladding to keep light in for conducting light entering
the end of the fiber, disruptions along at least a portion of the
length of the fiber to cause conducted light to be emitted from at
least one side of the fiber, and a heat sink in close proximity to
the light source adjacent the end of the fiber for cooling the
light source.
12. The light emitter of claim 11 wherein the light source is
surface mounted on a flex circuit in close proximity to the end of
the fiber.
13. A light emitter comprising at least one flat optical fiber
having opposite flat sides and opposite side edges and opposite
ends, at least one light source optically coupled to an end of the
fiber, the fiber having a light conducting core that is cladded by
an outer cladding to keep light in for conducting light entering
the end of the fiber, disruptions along at least a portion of the
length of the fiber to cause conducted light to be emitted from at
least one side of the fiber, and a hole extending through opposite
sides of the at least one fiber intermediate the side edges
downstream of the light source to permit access to opposite sides
of the light emitter through the hole without interfering with
conduction of light from the light source through the fiber
downstream of the hole.
14. A light emitter comprising at least one flat optical fiber
having opposite flat sides and opposite side edges and opposite
ends, at least one surface mount light source having substantially
the same thickness as the fiber optically coupled to an end of the
fiber, the fiber having a light conducting core that is cladded by
an outer cladding to keep light in for conducting light entering
the end of the fiber, disruptions along at least a portion of the
length of the fiber to cause conducted light to be emitted from at
least one side of the fiber, the light emitter being in combination
with a medical instrument, the at least one fiber extending along
at least a portion of the length of the medical instrument for
lighting an area adjacent the medical instrument, the fiber being
flexed to correspond to a non-planar shape of the medical
instrument.
15. A light emitter comprising at least one flat optical fiber
having opposite flat sides and opposite side edges and opposite
ends, at least one surface mount light source having substantially
the same thickness as the fiber optically coupled to an end of the
fiber, the fiber having a light conducting core that is cladded by
an outer cladding to keep light in for conducting light entering
the end of the fiber, and disruptions along at least a portion of
the length of the fiber to cause conducted light to be emitted from
at least one side of the fiber, the at least one light source
having a substantially less width than the fiber.
16. The light emitter of claim 15 wherein a plurality of surface
mount light sources each having substantially the same thickness as
the fiber and substantially less width than the fiber are optically
coupled to the end of the fiber in side-by-side relation to one
another across the width of the fiber.
17. The light emitter of claim 15 wherein the light source is
attached to an end of the fiber by a mechanical clip or
fastener.
18. The light emitter of claim 15 further comprising a heat sink
for cooling the light source.
19. A light emitter comprising at least one flat cladded optical
fiber having opposite flat sides and opposite side edges and ends,
at least one of the ends being adapted to receive light from a
light source for conduction of the light within the fiber, the
fiber having deformities in at least one of the sides to cause
conducted light to be emitted from at least one of the sides, and a
coating in intimate contact with at least one of the sides.
20. The light emitter of claim 19 wherein the coating is a
reflective coating that causes light emitted from the one side to
be reflected back toward the other side.
21. The light emitter of claim 19 wherein the deformities are in
both sides of the fiber, and the coating is a reflective coating
that is in intimate contact with one of the sides to cause light
emitted from the one side to be reflected back toward the other
side.
22. The light emitter of claim 19 wherein the coating completely
covers one of the sides, and only partially covers the other side
leaving open areas on the other side through which the conducted
light is emitted.
23. The light emitter of claim 19 further comprising at least one
surface mount light source optically coupled to an end of the
fiber, the light source having a thickness substantially
corresponding to the thickness of the fiber and having a width
equal to or less than the width of the fiber.
24. The light emitter of claim 23 wherein a plurality of surface
mount light sources are optically coupled to an end of the fiber,
each of the light sources having a width substantially less than
the width of the fiber.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application is a division of U.S. patent application
Ser. No. 10/900,000, filed Jul. 27, 2004, the entire disclosure of
which is incorporated herein by reference.
FIELD OF THE INVENTION
[0002] This invention generally relates to light emitting members
made of flat optical fibers that emit light received through one or
both ends out one or both sides to provide a desired light output
distribution.
BACKGROUND OF THE INVENTION
[0003] It is generally known to make light emitting members out of
light conducting panels, films, sheets, plates and optical fibers.
Light entering one or both ends of the light emitting members may
be emitted from one or both sides by providing disruptions on one
or both sides in a desired pattern.
[0004] An advantage in making light emitting members out of panels,
films, sheets and plates is that they are relatively inexpensive to
make. However, such light emitting panels, films, sheets and plates
are not as efficient in transmitting light as light emitting
members made out of optical fibers because they lack the cladding
that optical fibers have to keep the light in longer and allow the
light to be distributed/emitted where desired. Also it is difficult
to control the thickness of injection molded light emitting panels,
films, sheets and plates because of the stresses that occur in
different areas of the light emitting members during cooling after
molding.
[0005] Heretofore a major drawback in making light emitting members
out of optical fibers was the relatively high cost of manufacture.
Also because the optical fibers used were round optical fibers of
relatively small diameter, only a relatively small surface area of
each optical fiber could be disrupted during the manufacturing
process as compared to the amount of surface area of light emitting
panels, films, sheets and plates that could be disrupted. This
limited the relative overall brightness of light emitting members
made of optical fibers as compared to light emitting panels, films,
sheets and plates for a given light emitting surface area.
[0006] Another disadvantage of previous light emitting members made
of optical fibers was that the ends of the optical fibers had to be
bundled and secured together by a connector assembly that served as
an interface between the optical fiber ends and a light source.
Also it was difficult efficiently to couple a light source to such
bundled optical fiber end portions because of the minute gaps
between the optical fiber end portions and the irregular shape of
the bundled optical fiber end portions.
[0007] There is thus a need for light emitting members that have
the attributes of light emitting members made of both panels,
films, sheets and plates and optical fibers.
SUMMARY OF THE INVENTION
[0008] The light emitting members of the present invention are made
out of optical fibers instead of light emitting panels, films,
sheets or plates for increased efficiency in keeping the light in
longer and allowing the light to be distributed/emitted where
desired. However, instead of using round optical fibers, flat
optical fibers are used which have the advantage that more surface
area of the flat optical fibers can be disrupted using known
marring or abrading techniques for increased brightness for a given
light emitting surface area.
[0009] Another advantage in making light emitting members out of
flat optical fibers instead of round optical fibers is that the
ends of the flat optical fibers need not be bundled and secured
together by a connector assembly to serve as an interface between
the fiber ends and the light source as do round optical fibers.
Flat optical fibers may be manufactured in different thicknesses
and widths to make it easier and more efficient to couple one or
more light sources including particularly surface mount light
sources such as surface mount light emitting diodes to the flat
optical fiber ends. Surface mount light emitting diodes are
generally rectangular in cross section, which makes it relatively
easy to optically couple them to the ends of flat optical fibers by
making the flat optical fibers of substantially the same thickness
and either the same or greater width than the light sources. If the
flat optical fibers have a width substantially greater than that of
the light sources, multiple light sources may be optically coupled
to the end of each optical fiber to provide for increased
brightness. Also because the ends of the flat optical fibers need
not be bundled together by a connector assembly to serve as an
interface between the optical fiber ends and the light sources, the
need for space to receive and store bundled round optical fiber
ends is eliminated.
[0010] Still another advantage in making light emitting members out
of flat optical fibers instead of round optical fibers is that a
fewer number of wider flat optical fibers may be used to produce an
equivalent light output. Flat optical fiber light emitters may be
comprised of one or more flat optical fibers depending on the light
output requirements of the light emitters. Where multiple flat
optical fibers are used, the flat optical fibers may be held
together or mounted separately and may if desired have gaps
therebetween for lighting different areas of a display including
for example a liquid crystal display, a graphic overlay or
different rows of keys of a keyboard or the like.
[0011] In accordance with one aspect of the invention, the light
emitting members comprise one or more flat cladded optical fibers
having disruptions along at least a portion of their length to
cause conducted light to be emitted from at least one of the
sides.
[0012] In accordance with another aspect of the invention, the
disruptions may be formed in one or both sides of the flat optical
fibers by roughening, marring, abrading, etching, grit blasting or
thermoforming one or both sides of the flat optical fibers.
[0013] In accordance with another aspect of the invention, the
disruptions may be formed in a single inline process.
[0014] In accordance with another aspect of the invention, the
light emitting members may comprise a plurality of flat optical
fibers held together by an adhesive film or by mechanical clips or
fasteners.
[0015] In accordance with another aspect of the invention, the flat
optical fibers may have gaps therebetween for backlighting
different areas of a keyboard or other type of display.
[0016] In accordance with another aspect of the invention, the
thickness of the flat optical fibers may substantially correspond
to the thickness of the light sources including particularly
surface mount light sources such as surface mount light emitting
diodes (including polymer light emitting diodes and organic light
emitting diodes) for ease of optically coupling the light sources
to the flat optical fibers.
[0017] In accordance with another aspect of the invention, the flat
optical fibers may be of different widths which may be the same or
greater than the width of the light sources. If the width of the
flat optical fibers is substantially greater than that of the light
sources, multiple light sources may be optically coupled to each
flat optical fiber for increased brightness.
[0018] These and other objects, advantages, features and aspects of
the invention will become apparent as the following description
proceeds.
[0019] To the accomplishment of the foregoing and related ends, the
invention, then, comprises the features hereinafter more fully
described and particularly pointed out in the claims, the following
description and the annexed drawings setting forth in detail
certain illustrative embodiments of the invention, these being
indicative, however, of but several of the various ways in which
the principles of the invention may be employed.
BRIEF DESCRIPTION OF THE DRAWINGS
[0020] In the annexed drawings:
[0021] FIG. 1 is an enlarged schematic perspective view of a length
of flat optical fiber that may be used to make light emitting
members in accordance with the present invention.
[0022] FIG. 2 is a schematic illustration showing one way in which
one side of a flat optical fiber (of any desired length) may be
disrupted in a single inline process.
[0023] FIG. 3 is a schematic illustration similar to FIG. 2 but
showing one way in which both sides of the flat optical fiber may
be disrupted in a single inline process.
[0024] FIG. 4 is a schematic illustration showing one way in which
one of the sides of a plurality of flat optical fibers may be
disrupted in a single inline process.
[0025] FIG. 5 is a schematic illustration similar to FIG. 4 but
showing one way in which both sides of a plurality of flat optical
fibers may be disrupted in a single inline process.
[0026] FIG. 6 is an enlarged schematic fragmentary longitudinal
section through a flat optical fiber of a light emitting member
showing one disruption in one side and a reflective coating in
intimate contact with the optical fiber cladding on the other side
to cause reflected light to be reflected back toward the one
side.
[0027] FIG. 7 is an enlarged schematic fragmentary longitudinal
section similar to FIG. 6 but showing the reflective coating on the
same side of the flat optical fiber as the disruption to cause
refracted or reflected light to be reflected back toward the other
side.
[0028] FIG. 8 is an enlarged schematic fragmentary longitudinal
section similar to FIG. 7 but additionally showing a reflective
coating partially covering the other side of the flat optical fiber
leaving areas on the other side uncoated through which refracted or
reflected light may be emitted.
[0029] FIG. 9 is an enlarged schematic perspective view showing a
surface mount light source optically coupled to an end of a flat
optical fiber of a light emitting member.
[0030] FIG. 10 is an enlarged schematic perspective view showing
surface mount light sources optically coupled and mechanically
attached to the ends of a plurality of spaced apart flat optical
fibers of a light emitting member.
[0031] FIG. 11 is a schematic enlarged perspective view showing a
plurality of surface mount light sources optically coupled to an
end of one flat optical fiber of a light emitting member.
[0032] FIGS. 12 and 13 are enlarged schematic perspective views
similar to FIGS. 9 and 11 but showing the surface mount light
sources surface mounted on a flex circuit or the like.
[0033] FIG. 14 is an enlarged schematic perspective view showing a
plurality of surface mount light sources optically coupled to the
ends of a plurality of flat optical fibers of a light emitting
member wherein the optical fibers are shown held together by an
adhesive film.
[0034] FIG. 15 is an enlarged schematic perspective view showing a
plurality of flat optical fibers of a light emitting member held
together by a mechanical clip or fastener with gaps between the
optical fibers.
[0035] FIG. 16 is an enlarged schematic perspective view showing a
plurality of surface mount light sources optically connected to an
end of a plurality of flat optical fibers of a light emitting
member.
[0036] FIGS. 17-20 are enlarged schematic views showing surface
mount light sources optically coupled to an end of flat optical
fibers of light emitting members wherein the optical fiber ends
have different shapes to redirect or focus the light into the
optical fibers.
[0037] FIG. 21 is an enlarged schematic perspective view of a
surface mount light source optically coupled to an end of a flat
optical fiber of a light emitting member similar to FIG. 9 but
showing a heat sink in close relation to the light source for
cooling the light source.
[0038] FIG. 22 is an enlarged schematic perspective view showing a
surface mount light source optically coupled to an end of a flat
optical fiber of a light emitting member similar to FIG. 9 but
showing a hole extending through opposite sides of the optical
fiber to permit access to opposite sides of the light emitting
member through the hole.
[0039] FIG. 23 is an enlarged schematic perspective view showing a
plurality of flat optical fibers of a light emitting member
extending behind a plurality of rows of keys of a keypad with gaps
between the optical fibers corresponding to the spacing between the
rows of keys so one of the optical fibers extends behind each row
of keys for backlighting one or more keys in each row.
[0040] FIG. 24 is an enlarged schematic perspective view showing a
plurality of flat optical fibers of a light emitting member
backlighting a liquid crystal display.
[0041] FIG. 25 is an enlarged schematic perspective view showing a
plurality of flat optical fibers of a light emitting member
backlighting a graphic overlay.
[0042] FIG. 26 is an enlarged schematic perspective view showing a
flat optical fiber of a light emitting member extending along a
surface of a medical instrument such as a retractor for lighting an
area adjacent the retractor.
DETAILED DESCRIPTION OF THE INVENTION
[0043] Referring now in detail to the drawings, wherein the same
reference numbers are used to designate like parts, and initially
to FIG. 1, there is shown a flat optical fiber 1 of any desired
length having opposite flat sides 2 and 3 and opposite side edges 4
and 5 and ends 6 and 7. The flat optical fiber 1 has a light
transmitting core portion 8 made of a suitable optically
transparent material such as glass or plastic having the desired
optical characteristics and flexibility. Surrounding the core
portion 8 is an outer sheath or cladding 9 having an index of
refraction that is different than that of the core material,
whereby substantially total internal reflection is obtained at the
core-cladding interface, as well known in the art.
[0044] To cause conducted light entering one or both ends of one or
more flat optical fibers 1 to be emitted from one or both sides 2
and 3 thereof, the flat optical fibers may be disrupted at one or
more areas along their length as by roughening, marring, abrading,
etching, grit blasting or thermally deforming one or both sides.
FIGS. 2-5 schematically show one way of disrupting one or both
sides of one or more flat optical fibers in a single inline process
by passing the flat optical fibers between a pair of rotating
pressure rollers 10 and 11.
[0045] One or more flexible flat optical fibers of any desired
length may be wound on a spool or spindle (not shown) for ease of
handling and storage and pulled off the spool and passed between a
pair of opposed pressure rollers to provide disruptions 12 on one
or both sides of the fibers. In FIGS. 2 and 4 the surface of only
one of the rollers 10 may be roughened or serrated or covered with
a diamond coating or grit sandpaper or other suitable abrasive
material to provide an abrasive surface 15 thereon for disrupting
(e.g., marring or abrading) one side 2 of one or more flat optical
fibers during passage between the rollers with the rollers pressing
against the fibers in a single inline process. The other roller may
be hard or have a deformable cover as desired. In FIGS. 3 and 5,
the surface of both rollers 10 and 11 may be provided with an
abrasive surface 12 of suitable type for marring or abrading both
sides 2 and 3 of one or more flexible flat optical fibers during
passage between the rollers with the rollers pressing against the
fibers in a single inline process.
[0046] The size, depth, density and/or location of the disruptions
12 in one or both sides of the flat optical fibers may be varied as
desired as by moving the rollers toward and away from each other
during the marring or abrading process to cause conducted light to
be emitted from one or both sides of the fibers in a uniform or
non-uniform pattern as desired.
[0047] A reflective coating may be directly applied in intimate
contact to the cladding surface 9 on one side of the flat optical
fibers 1 to act as a back reflector for reflecting the conducted
light toward the opposite side. FIG. 6 schematically shows a
reflective coating 16 in intimate contact with the cladding 9 on
the side 3 of the flat optical fiber 1 opposite the side 2 having
the disruptions 12 (only one of which is shown) for reflecting
conducted light CL back toward the side with the disruptions,
whereas FIG. 7 shows the reflective coating 16 in intimate contact
with the cladding 9 on the side 2 having the disruptions 12 for
reflecting the conducted light CL from that side back toward the
other side 3. Also FIG. 8 shows the reflective coating 16
completely covering the side 2 of the flat optical fibers 1 having
the disruptions 12 thereon and only partially covering the other
side 3 leaving uncovered areas 17 on the other side through which
refracted or reflected light may be emitted.
[0048] The size (including thickness, width and length) of the flat
optical fibers as well as the number of flat optical fibers used to
make a particular light emitting member in accordance with the
present invention may be varied depending on the particular
application, as may the size, type and number of light sources used
to supply light to one or both ends of the flat optical fibers.
However, the flat optical fibers used to make a particular light
emitting member will typically have a thickness of between 0.010
inch and 0.035 inch and a width of between 0.070 inch and 3 inches,
with a ratio of thickness to width of less than 0.5. Also the flat
optical fibers will typically have a length greater than 5 inches,
with a ratio of thickness to length of less than 0.007.
[0049] FIGS. 9 and 11 show light emitting members 20 and 21 each
comprised of a single flat optical fiber 1 of different widths,
lengths and/or thicknesses, whereas FIGS. 10 and 14-16 show light
emitting members 22-25, respectively, each comprised of multiple
flat optical fibers 1 of different lengths, widths and/or
thicknesses. In FIGS. 9, 10, 14 and 15 the flat optical fibers 1
are shown as having a thickness and width substantially
corresponding to the thickness and width of a suitable surface
mount type light source 30 such as a surface mount light emitting
diode (LED) for direct coupling of the light sources to an end of
the optical fibers. The flat optical fibers 1 shown in FIGS. 11 and
16 also have a thickness substantially corresponding to the
thickness of a surface mount type light source, but have a width
substantially greater than the width of a surface mount type light
source to permit direct coupling of a plurality of such light
sources to an end of each optical fiber.
[0050] For example, the surface mount type LED 30 may have a
rectangular cross-sectional shape with a thickness of approximately
0.030 inch and a width of approximately 0.200 inch, and the flat
optical fibers 1 may have substantially the same thickness as the
LEDs and either substantially the same width as the LEDs for
optically coupling one LED to an end of each flat optical fiber as
shown in FIGS. 9, 10, 14 and 15 or a substantially greater width
for coupling multiple light sources to an end of each flat optical
fiber as shown in FIGS. 11 and 16. As used herein, the term light
emitting diode or LED means and includes a standard surface mount
type LED as well as a surface mount type polymer light emitting
diode (PLED) or surface mount type organic light emitting diode
(OLED).
[0051] One or more light sources 30 may be attached to an end of
one or more flat optical fibers 1 by a mechanical clip or fastener
31 as shown in FIG. 10. Alternatively the light sources 30 may
simply be positioned and supported adjacent an end of the flat
optical fibers as shown in FIGS. 9, 11, and 14-16. Where the light
emitting members are comprised of a plurality of flat optical
fibers, the flat optical fibers may be independently positioned and
supported relative to one another as shown in FIGS. 10 and 16 or
held together by an adhesive film 32 as shown in FIG. 14 or by
mechanical clips or fasteners 33 as shown in FIG. 15. In any case,
where the light sources are surface mount type light sources, side
tabs or bottom contacts (not shown) may be provided on the light
sources for surface mounting one or more light sources on a flex
strip or other type of flex circuit 34 in close proximity to an end
of one or more flat optical fibers as schematically shown in FIGS.
12 and 13.
[0052] It is also important to polish the ends of the flat optical
fibers to which the light sources are optically coupled for more
efficient coupling of the light to the ends of the optical fibers.
Moreover, the ends of the flat optical fibers 1 that receive light
from one or more light sources may either be substantially flat as
schematically shown at 35 in FIG. 17 or lens shaped as
schematically shown in FIGS. 18-20 to redirect or focus the light
into the ends of the fibers. In FIG. 18 the end 36 of the fiber is
shown as being transversely curved across its entire width, whereas
in FIGS. 19 and 20 the ends 37 and 38 of the fibers are shown as
having different lens shapes 39 and 40 intermediate their width.
Also the lens shape 39 is shown in FIG. 16 as being recessed within
the end 37 of the fiber.
[0053] A heat sink 41 may be placed in close proximity to the light
source 30 adjacent an end of a flat optical fiber light emitting
member 42 as schematically shown in FIG. 21 to aid in cooling the
light source. Moreover, a hole 43 may extend through opposite sides
of one or more flat optical fibers 1 of a light emitting member 44
intermediate the side edges 4 and 5 of the flat optical fibers as
schematically shown in FIG. 22 to permit access to one side of the
light emitting member from the other side or vice versa through the
hole without interfering with the conduction of light through the
particular flat optical fiber containing the hole downstream of the
hole.
[0054] Where the light emitting members are comprised of a
plurality of flat optical fibers, the spacing between the flat
optical fibers may be varied as desired to suit a particular
application. For example, where such a light emitting member 50 is
used to backlight a keypad 51 having a plurality of rows of keys
52, suitable gaps 53 may be provided between the flat optical
fibers 1 substantially corresponding to the spacing between a
plurality of rows of the keys so the flat optical fibers extend
behind a plurality of rows of the keys as schematically shown in
FIG. 23 for backlighting one or more keys in each row. In other
applications the flat optical fibers 1 that comprise a light
emitting member 55 may be placed closer together for backlighting a
display 56 such as a liquid crystal display 57 as schematically
shown in FIG. 24 or a graphic overlay 58 as schematically shown in
FIG. 25.
[0055] Moreover, the light emitting member 60 may be comprised of a
single flat optical fiber 1 having a desired width and length
corresponding to the width and length of a portion of a medical
instrument 61 such as a retractor blade 62 as schematically shown
in FIG. 26. The flat optical fiber 1 may also be bent or flexed to
correspond to the shape of the retractor blade or other medical
instrument and have a surface mount light source 30 optically
coupled to one end of the flat optical fiber 1 as further shown in
FIG. 26 for lighting an area adjacent at least a portion of the
length of the medical instrument.
[0056] Although the invention has been shown and described with
respect to certain embodiments, it is obvious that equivalent
alterations and modifications will occur to others skilled in the
art upon the reading and understanding of the specification. In
particular, with regard to the various functions performed by the
above described components, the terms (including any reference to a
"means") used to describe such components are intended to
correspond, unless otherwise indicated, to any component which
performs the specified function of the described component (e.g.,
that is functionally equivalent), even though not structurally
equivalent to the disclosed component which performs the function
in the herein illustrated exemplary embodiments of the invention.
In addition, while a particular feature of the invention may have
been disclosed with respect to only one embodiment, such feature
may be combined with one or more other features as may be desired
or advantageous for any given or particular application.
* * * * *