LGD_000434
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`LG Display Ex. 1006
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`

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`U.S. Patent
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`Mar. 25, 1997
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`Sheet 1 of 4
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`5,613,751
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`LG D_000435
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`LGD_000435
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`

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`U.S. Patent
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`Mar. 25, 1997
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`Sheet 2 of 4
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`4 5,613,751
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`If H
`30
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`27
`28
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`48
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`F|G.8
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`LG D_000436
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`LGD_000436
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`U.S. Patent
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`Mar. 25, 1997
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`Sheet 3 of 4
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`5,613,751
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`:51
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`FIG. I2"
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`LG D_000437
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`LGD_000437
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`

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`U.S. Patent
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`Mar. 25, 1997
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`Sheet 4 of 4
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`5,613,751
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`73
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`i
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`7'
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`/7o
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`FIG. :3
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`LG D_000438
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`LGD_000438
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`1
`LIGHT EMITTING PANEL ASSEMBLIES
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`2
`BRIEF DESCR.lPTION OF THE DRAWINGS
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`5,613,751
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`BACKGROUND OF THE INVENTION
`
`to light
`This invention relates generally, as indicated,
`emitting panel assemblies each including a transparent panel
`member for efliciently conducting light, and controlling the
`light conducted by the panel member to be emitted from one
`or more light output areas along the length thereof.
`Light emitting panel assemblies are generally known.
`However, the present invention relates to several diiferent
`light emitting panel assembly configurations which provide
`for better control of the light output from the panel assem-
`blies and for more eflicient utilization of light, which results
`in greater light output from the panel assemblies.
`
`SUMMARY OF THE INVENTION
`
`In accordance with one aspect of the invention, the light
`emitting panel assemblies include a light emitting panel
`member having a light transition area in which at least one
`light source is suitably mounted for transmission of light to
`the light input surface of the panel member.
`In accordance with another aspect of the invention, the
`light source is desirably embedded, potted or bonded to the
`light transition area to eliminate any air gaps, decrease
`surface reflections andlor eliminate any lens elfect between
`the light source and light transition area, thereby reducing
`light loss and increasing the light output from the panel
`assembly.
`In accordance with another aspect of the invention, the
`panel assemblies may include reflective or refractive sur-
`faces for changing the path of a portion of the light, emitted
`from the light source, that would not normally enter the
`panel members at an acceptable angle that allows the light
`to remain in the panel members for a longer period of time
`and/or increase the efliciency of the panel members.
`In accordance with another aspect of the invention, the
`light emitting panel members include a pattern of light
`extracting deformities or disruptions which provide a
`desired light output distribution from the panel members by
`changing the angle of refraction of a portion of the light from
`one or more light output areas of the panel members.
`In accordance with still another aspect of the invention,
`the light source may include multiple colored light sources
`for supplying light to one or more light output areas, and for
`providing a colored or white light output distribution.
`In accordance with yet another aspect of the invention, the
`panel assemblies include a transition area for mixing the
`multiple colored lights, prior to the light entering the panel
`members, in order to effect am desired colored or white light
`output distribution.
`The various light emitting panel assemblies of the present
`invention are very efficient panel assemblies that may be
`used to produce increased uniformity and higher light output
`from the panel members with lower power requirements,
`and allow the panel members to be made thinner andlor
`longer, and/or of various shapes and sizes.
`To the accomplishment of the foregoing and related ends,
`the invention then comprises the features hereinafter 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.
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`In the annexed drawings:
`FIGS. 1 through 3 are schematic perspective views of
`three diiferent forms of light emitting panel assemblies in
`accordance with this invention;
`FIG. 4a is an enlarged plan view of a portion of a light
`output area of a panel assembly showing one form of pattern
`of light extracting deformities on the light output area;
`FIGS. 4b, c and d are enlarged schematic perspective
`views of a portion of a light output area of a panel assembly
`showing other forms of light extracting deformities formed
`in or on the light output area;
`FIG. 5 is an enlarged transverse section through the light
`emitting panel assembly of FIG. 3 taken generally on the
`plane of the line 5-5 thereof;
`FIG. 6 is a schematic perspective view of another form of
`light emitting panel assembly in accordance with this inven-
`tion;
`
`FIG. 7 is a schematic top plan view of another form of
`light emitting panel assembly in accordance with this inven-
`tion;
`
`FIG. 8 is a schematic perspective view of another form of
`light emitting panel assembly in accordance with this inven-
`tion;
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`FIG. 9 is a schematic top plan view of another form of
`light emitting panel assembly in accordance with this inven-
`tion;
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`FIG. 10 is a schematic top plan view of still another form
`of light emitting panel assembly in accordance with this
`invention;
`
`FIG. 11 is a side elevation view of the light emitting panel
`assembly of FIG. 10;
`FIG. 11a is a fragmentary side elevation view showing a
`tapered or rounded end on the panel member in place of the
`prismatic surface shown in FIGS. 10 and 11;
`FIG. 12 is a schematic top plan view of another form of
`light emitting panel assembly in accordance with this inven-
`tion;
`
`FIG. 13 is a schematic side elevation view of the light
`emitting panel assembly of FIG. 12; and
`FIGS. 14 and 15 are schematic perspective views of still
`other forms of light emitting panel assemblies in accordance
`with this invention.
`'
`
`DETAILED DESCRIPTION OF THE
`PREFERRED EMBODIMENTS
`
`Referring now in detail to the drawings, and initially to
`FIG. 1, there is schematically shown one form of light
`emitting panel assembly 1 in accordance with this invention
`including a transparent light emitting panel 2 and one or
`more light sources 3 which emit light in a predetermined
`pattern in a light transition member or area 4 used to make
`the transition from the light source 3 to the light emitting
`panel 2, as well known in the art. The light that is transmitted
`by the light transition area 4 to the transparent light emitting
`panel 2 may be emitted along the entire length of the panel
`or from one or more light output areas along the length of the
`panel as desired to produce a desired light output distribu-
`tion to fit a particular application.
`In FIG. 1 the light transition area 4 is shown as an integral
`extension of ‘one end of the light emitting panel 2 and as
`being generally rectangular in shape. However, the light
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`LG D_000439
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`LGD_000439
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`3
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`transition area may be of other shapes suitable for embed-
`ding, potting, bonding or otherwise mounting the light
`source. Also, reflective or refractive surfaces may be pro-
`vided to increase efficiency. Moreover, the light transition
`area 4 may be a separate piece suitably attached to the light
`input surface 13 of the panel member if desired. Also, the
`sides of the light transition area may be curved to more
`efliciently reflect or refract a portion of the light emitted
`from the light source through the light emitting panel at an
`acceptable angle.
`‘
`FIG. 2 shows another form of light emitting panel assem-
`bly 5 in accordance with this invention including a panel
`light transition area 6 at one end of the light emitting panel
`7 with sides 8, 9 around and behind the light source 3 shaped
`to more efliciently reflect and/or refract and focus the light
`emitted from the light source 3 that impinges on these
`surfaces back through the light
`transition area 6 at an
`acceptable angle for entering the light input surface 18 at one
`end of the light emitting panel 7. Also, a suitable reflective
`material or coating 10 may be provided on the portions of
`the sides of the light transition areas of the panel assemblies
`of FIGS. 1 and 2 on which a portion of the light impinges
`for maximizing the amount of light or otherwise changing
`the light that is reflected back through the light transition
`areas and into the light emitting panels.
`The panel assemblies shown in FIGS. 1 and 2 include a
`single light source 3, whereas FIG. 3 shows another light
`emitting panel assembly 11 in accordance with this inven-
`tion including two light sources 3. Of course, it will be
`appreciated that the panel assemblies of the present inven-
`tion may be provided with any number of light sources as
`desired, depending on the particular application.
`The panel assembly 11,of FIG. 3 includes a light transition
`area 12 at one end of the light emitting panel 14 having
`reflective and/or refractive surfaces 15 around and behind
`each light source 3. These surfaces 15 may be appropriately
`shaped including for example curved, straight andlor faceted
`surfaces, and if desired, suitable reflective materials or
`coatings may be provided on portions of these surfaces to
`more efiiciently reflect and/or refract and focus a portion of
`the light emitted for example from an incandescent light
`source which emits light in a 360° pattern through the light
`transition areas 12 into the light input surface 19 of the light
`emitting panel 14.
`The light sources 3 may be mechanically held in any
`suitable manner in slots, cavities or openings 16 machined,
`molded or otherwise formed in the light transition areas of
`the panel assemblies. However, preferably the light sources
`3 are embedded, potted or bonded in the light transition
`areas in order to eliminate any air gaps or air interface
`surfaces between the light sources and surrounding light
`transition areas, thereby reducing light loss and increasing
`the light output emitted by the light emitting panels. Such
`mounting of the light sources may be accomplished, for
`example, by bonding the light sources 3 in the slots, cavities
`or openings 16 in the light transition areas using a suflicient
`quantity of a suitable embedding, potting or bonding mate-
`rial 17. The slots, cavities or openings 16 may be on the top,
`bottom, sides or back of the light transition areas. Bonding
`can also be accomplished by a variety of methods that do not
`incorporate extra material, for example, thermal bonding,
`heat staking, ultrasonic or plastic welding or the like. Other
`methods of bonding include insert molding and casting
`around the light source(s).
`A transparent light emitting material of any suitable type,
`for example acrylic or polycarbonate, may be used for the
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`light emitting panels. Also, the panels may be substantially
`flat, or curved, may be a single layer or multi-layers, and
`may have different thicknesses and shapes. Moreover, the
`panels may be flexible, or rigid, and may be made out of a
`variety of compounds. Further, the panels may be hollow,
`filled with liquid, air, or be solid, and may have holes or
`ridges in the panels.
`Each light source 3 may also be of any suitable type
`including, for example, any of the types disclosed in U.S.
`Pat. Nos. 4,897,771 and 5,005,108, assigned to the same
`assignee as the present application, the entire disclosures of
`which are incorporated herein by reference. In particular, the
`light sources 3 may be an arc lamp, an incandescent bulb
`which also may be colored, filtered or painted, a lens end
`bulb, a line light, a halogen lamp, a light emitting diode
`(LED), a chip from an LED, a neon bulb, a fluorescent tube,
`a fiber optic light pipe transmitting from a remote source, a
`laser or laser diode, or any other suitable light source.
`Additionally, the light sources 3 may be a multiple colored
`LED, or a combination of multiple colored radiation sources
`in order to provide a desired colored or white light output
`distribution. For example, a plurality of colored lights such
`as LEDs of difl’erent colors (red, blue, green) or a single
`LED with multiple colored chips may be employed to create
`white light or any other colored light output distribution by
`varying the intensities of each individual colored light.
`A pattern of light extracting deformities or disruptions
`may be provided on one or both sides of the panel members
`or on one or more selected areas on one or both sides of the
`
`panel members, as desired. FIG. 4a schematically shows one
`such light surface area 20 on which a pattern of light
`extracting deformities or disruptions 21 is provided. As used
`herein, the term deformities or disruptions are used inter-
`changeably to mean any change in the shape or geometry of
`the panel surface and/or coating or surface treatment that
`causes a portion of the light to be emitted. The pattern of
`light extracting deformities 21 shown in FIG. 4a includes a
`variable pattern which breaks up the light rays such that the
`internal angle of reflection of a portion of the light rays will
`be great enough to cause the light rays either to be emitted
`out of the panel through the side or sides on which the light
`extracting deformities 21 are provided or reflected back
`through the panel and emitted out the other side.
`These deformities or disruptions 21 can be produced in a
`variety of manners, for example, by providing a painted
`pattern, an etched pattern, a machined pattern, a printed
`pattern, a hot stamped pattern, or a molded pattern or the like
`on selected light output areas of the panel members. An ink
`or printed pattern may be applied for example by pad
`printing, silk screening, ink jet, heat transfer film process or
`the like. The deformities may also be printed on a sheet or
`film which is used to apply the deformities to the panel
`member. This sheet or film may become a permanent part of
`the light panel assembly for example by attaching or other-
`wise positioning the sheet or film against one or both sides
`of the panel member similar to the sheet or film 27 shown
`in FIGS. 3 and 5 in order to produce a desired effect.
`By varying the density, opaqueness or translucence,
`shape, depth, color, area, index of refraction, or type of
`deformities 21 on an area or areas of the panels, the light
`output of the panels can be controlled. The deformities or
`disruptions may be used to control
`the percent of light
`emitted from any area of the panels. For example, less and/or
`smaller size deformities 21 may be placed on panel areas
`where less light output is wanted. Conversely, a greater
`percentage of and/or larger deformities may be placed on
`areas of the panels where greater light output is desired.
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`LG D_000440
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`LGD_000440
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`5
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`5,613,751
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`Varying the percentages and/or size of deformities in
`different areas of the panel is necessary in order to provide
`a uniform light output distribution. For example, the amount
`of light traveling through the panels will ordinarily be
`greater in areas closer to the light source than in other areas
`further removed from the light source. A pattern of light
`extracting deformities 21 may be used to adjust for the light
`variances within the panel members, for example, by pro-
`viding a denser concentration of light extracting deformities
`with increased distance from the light source 3 thereby
`resulting in a more uniform light output distribution from the
`light emitting panels.
`The deformities 21 may also be used to control the output
`ray angle distribution of the emitted light to suit a particular
`application. For example, if the panel assemblies are used to
`provide a liquid crystal display backlight, the light output
`will be more eflicient if the deformities 21 cause the light
`rays to emit from the panels at predetermined ray angles
`such that they will pass through the liquid crystal display
`with low loss.
`
`Additionally, the pattern of light extracting deformities
`may be used to adjust for light output variances attributed to
`light extractions of the panel members. The pattern of light
`extracting deformities 21 may be printed on the light output
`areas utilizing a wide spectrum of paints, inks, coatings,
`epoxies, or the like, ranging from glossy to opaque or both,
`and may employ half-tone separation techniques to vary the
`deformity 21 coverage. Moreover,
`the pattern of light
`extracting deformities 21 may be multiple layers or vary in
`index of refraction.
`
`Print patterns of light extracting deformities 21 may vary
`in shapes such as dots, squares, diamonds, ellipses, stars,
`random shapes, and the like, and are desirably 0.006 square
`inch per deformity/element or less. Also, print patterns that
`are 60 lines per inch or finer are desirably employed, thus
`making the deformities or shapes 21 in the print patterns
`nearly invisible to the human eye in a particular application
`thereby eliminating the detection of gradient or banding
`lines that are common to light extracting patterns utilizing
`larger elements. Additionally, the deformities may vary in
`shape and/or size along the length and/or width of the panel
`members. Also, a random placement pattern of the defor—
`mities may be utilized throughout the length and/or width of
`the panel members. The deformities may have shapes or a
`pattern with no specific angles to reduce moire or other
`interference effects. Examples of methods to create these
`random patterns are printing a pattern of shapes using
`stochastic print pattern techniques, frequency modulated
`half tone patterns, or random dot half tones. Moreover, the
`deformities may be colored in order to elfect color correction
`in the panel members. The color of the deformities may also
`vary throughout the panel members, for example to provide
`difierent colors for the same or different light output areas.
`In addition to or in lieu of the patterns of light extracting
`deformities 21 shown in FIG. 4a, other light extracting
`deformities including prismatic surfaces, depressions or
`raised surfaces of various shapes using more complex
`shapes in a mold pattern may be molded, etched, stamped,
`therrnoforrned, hot stamped or the like into or on one or
`more areas of the panel member. FIGS. 4b and 4c show
`panel areas 22 on which prismatic surfaces 23 or depressions
`24 are formed in the panel areas, whereas FIG. 4d shows
`prismatic or other reflective or refractive surfaces 25 formed
`on the exterior of the panel area. The prismatic surfaces,
`depressions or raised surfaces will cause a portion of the
`light rays contacted thereby to be emitted from the panel
`member. Also, the angles of the prisms, depressions or other
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`in different
`the light
`surfaces may be varied to direct
`directions to produce a desired light output distribution or
`efiect. Moreover, the reflective or refractive surfaces may
`have shapes or a pattern with no specific angles to reduce
`moire or other interference effects.
`
`As best seen in the cross sectional view of FIG. 5, a back
`reflector (including trans reflectors) 26 may be attached or
`positioned against one side of the panel member 14 of FIG.
`3 using a suitable adhesive 28 or other method in order to
`improve light output efliciency of the panel assembly 11 by
`reflecting the light emitted from that side back through the
`panel for emission through the opposite side. Additionally, a
`pattern of light extracting deformities 21, 23, 24 and/or 25
`may be provided on one or both sides of the panel member
`in order to change the path of the light so that the internal
`critical angle is exceeded and a portion of the light is emitted
`from one or both sides of the panel. Moreover, a transparent
`film, sheet or plate 27 may be attached or positioned against
`the side or sides of the panel member from which light is
`emitted using a suitable adhesive 28 or other method in order
`to produce a desired effect.
`The member 27 may be used to further improve the
`uniformity of the light output distribution. For example, the
`member 27 may be a colored film, a diffuser, or a label or
`display, a portion of which may be a transparent overlay that
`may be colored and/or have text or an image thereon.
`If adhesive 28 is used to adhere the back reflector 26
`and/or film 27 to the panel,
`the adhesive is preferably
`applied only along the side edges of the panel, and if desired
`the end edge opposite the light transition areas 12, but not
`over the entire surface area or areas of the panel because of
`the difliculty in consistently applying a uniform coating of
`adhesive to the panel. Also, the adhesive changes the inter~
`nal critical angle of the light in a less controllable manner
`than the air gaps 30 (see FIG. 5) which are formed between
`the respective panel surfaces and the back reflector 26 and/or
`film 27 when only adhered along the peripheral edges.
`Additionally, longer panel members are achievable when air
`gaps 30 are used. If adhesive were to be used over the entire
`surface,
`the pattern of deformities could be adjusted to
`account for the additional attenuation in the light caused by
`the adhesive.
`
`Referring further to FIG. 2, the panel assembly 5 shown
`therein also includes molded posts 31 at one or more comers
`of the panel 7 (four such posts being shown) which may be
`used to facilitate mounting of the panel assembly and
`providing structural support for other parts or components,
`for example, a display panel such as a liquid crystal display
`panel as desired.
`FIG. 6 shows another form of light emitting panel assem-
`bly 32 in accordance with this invention including a panel
`member 33, one or more light sources 3, and one or more
`light output areas 34. In addition, the panel assembly 32
`includes a tray 35 having a cavity or recess 36 in which the
`panel assembly 32 is received. The tray 35 may act as a back
`reflector as well as end edge and/or side edge reflectors for
`the panel 33 and side and/or back reflectors 37 for the light
`sources 3. Additionally, one or more secondary reflective or
`refractive surfaces 38 may be provided on the panel member
`33 and/or tray 35 to reflect a portion of the light around one
`or more corners or curves in a non-rectangular shaped panel
`member 33. These secondary reflective/refractive surfaces
`38 may be flat, angled, faceted or curved, and may be used
`to extract a portion of the light away from the panel member
`in a predetermined pattern. FIG. 6 also shows multiple light
`output areas 34 on the panel member that emit light from one
`or more light sources 3.
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`LG D_000441
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`LGD_000441
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`5,613,751
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`7
`FIG. 7 is a schematic illustration of still another form of
`light emitting panel assembly 40 in accordance with this
`invention including a panel member 41 having one or more
`light output areas 42 and one or more light transition areas
`(mixing areas) 43 containing a plurality of light sources 3 at
`one or both ends of the panel. Each transition area mixes the
`light from one or more light sources having difierent colors
`and/or intensities. In this particular embodiment, each of the
`light sources 3 desirably employs three colored LEDs (red,
`blue, green) in each transition mixing area 43 so that the
`light from the three LEDs can be mixed to produce a desired
`light output color that will be emitted from the light output
`area 42. Alternatively, each light source may be a single
`LED having multiple colored chips bonded to the lead film.
`Also, two colored LEDs or a single LED having two colored
`chips may be used for a particular application. By varying
`the intensities of the individual respective LEDs, virtually
`any colored light output or white light distribution can be
`achieved.
`
`FIG. 8 shows yet another form of light emitting panel
`assembly 45 in accordance with this invention including a
`light emitting panel member 46 and a light source 3 in a light
`transition area 48 integral with one end of the panel member.
`In this particular embodiment,
`the panel member 46 is
`three-dimensionally curved, for example, such that light rays
`may be emitted in a manner that facilitates aesthetic design
`of a lighted display.
`FIG. 9 schematically shows another form of light emitting
`panel assembly 50in accordance with this invention, includ-
`ing a panel member 51 having multiple light output areas 52,
`and mounting posts and/or mounting tabs 53. This particular
`panel assembly 50 may serve as a structural member to
`support other parts or components as by providing holes or
`cavities 54, 55 in the panel member 51 which allow for the
`insertion of modular components or other parts into the
`panel member. Moreover, a separate cavity or recess 56 may
`be provided in the panel member 51 for receipt of a
`correspondingly shaped light transition area 57 having one
`or more light sources 3 embedded, bonded, cast,
`insert
`molded, epoxied, or otherwise mounted or positioned
`therein and a curved reflective or refractive surface 58 on the
`transition area 57 and/or wall of the cavity or recess 56 to
`redirect a portion of the light in a predetermined manner. In
`this way the light transition area 57 and/or panel member
`may be in the form of a separate insert which facilitates the
`easy placement of the light source in a modular manner. A
`reflector 58 may be placed on the reflective or refractive
`surface of the cavity or recess 56 or insert 57. Where the
`reflector 58 is placed on the reflective or refractive surface
`of the cavity or recess 56, the cavity or recess may act as a
`mold permitting transparent material from which the tran-
`sition area 57 is made to be cast around one or more light
`sources 3.
`
`FIGS. 10 and 11 schematically show another form of light
`emitting panel assembly 60 in accordance with this inven-
`tion including a panel member 61 having one or more light
`output areas 62. In this particular embodiment, an olf-axis
`light transition area 63 is provided that is thicker in cross
`section than the panel member to permit use of one or more
`light sources 3 embedded or otherwise mounted in the light
`transition area that are dimensionally thicker than the panel
`member. Also, a three-dimensional reflective surface 64
`(FIG. 11) may be provided on the transition area 63. More-
`over, a prism 65 (FIG. 11) or tapered, rounded, or otherwise
`shaped end 66 (FIG. 11a) may be provided at the end of the
`panel opposite the light sources 3 to perform the function of
`an end reflector. The light sources 3 may be oriented at
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`different angles relative to each other and oifset to facilitate
`better mixing of the light rays 67 in the transition area 63 as
`schematically shown in FIG. 10 and/or to permit a shorter
`length transition area 63 to be used.
`FIGS. 12 and 13 schematically show still another form of
`light emitting panel assembly 70 in accordance with this
`invention which includes one or more light transition areas
`71 at one or both ends of the panel member 72 each
`containing a single light source 73. The transition area or
`areas 71 shown in FIGS. 12 and 13 collect light with
`multiple or three-dimensional surfaces and/or collect light in
`more than one plane. For example each transition area 71
`shown in FIGS. 12 and 13 has elliptical and parabolic shape
`surfaces 74 and 75 in diiferent planes for directing the light
`rays 76 into the panel member at a desired angle.
`Providing one or more transition areas at one or both ends
`of the panel member of any desired dimension to accom-
`modate one or more light sources, with reflective and/or
`refractive surfaces on the transition areas for redirecting the
`light rays into the panel member at relatively low angles
`allows the light emitting panel member to be made much
`longer and thinner than would otherwise be possible. For
`example the panel members of the present invention may be
`made very thin, i.e., 0.125 inch thick or less.
`FIG. 14 schematically illustrates still another form of light
`emitting panel assembly 80 in accordance with this inven-
`tion including a light emitting panel 81 and one or more light
`sources 3 positioned, embedded, potted, bonded or other-
`wise mounted in a light transition area 82 that is at an angle
`relative to the panel member 81 to permit more eflicient use
`of space. An angled or curved reflective or refractive surface
`83 is provided at the junction of the panel member 81 with
`the transition area 82 in order to reflect/refract light from the
`light source 3 into the body of the panel member 81 for
`emission of light from one or more light emitting areas 84
`along the length of the panel member.
`FIG. 15 schematically illustrates still another form of light
`emitting panel assembly 90 in accordance with this inven-
`tion including a light transition area 91 at one or both ends
`of a light emitting panel member 92 containing a slot 93 for
`sliding receipt of an LED or other suitable light source 3.
`Preferably the slot 93 extends into the transition area 91
`from the back edge 94, whereby the light source 3 may be
`slid and/or snapped in place in the slot from the back, thus
`allowing the transition area to be made shorter and/or
`thinner. The light source 3 may be provided with wings, tabs
`or other surfaces 95 for engagement in correspondingly
`shaped recesses or grooves 96 or the like in the transition
`area 91 for locating and, if desired, securing the light source
`in place. Also, the light source 3 may be embedded, potted,
`bonded or otherwise secured within the slot 93 in the light
`transition area 91 of the panel member 92. Light from a
`secondary light source 97 may be projected through the
`panel member 92 for indication or some other eifect.
`The various light emitting panel assemblies disclosed
`herein may be used for a great many different applications
`including for example LCD back lighting or lighting in
`general, decorative and display lighting, automotive light-
`ing, dental lighting, phototherapy or other medical lighting,
`membrane switch lighting, and sporting goods and apparel
`lighting or the like. Also the panel assemblies may be made
`such that the panel members and deformities are transparent
`without a back reflector. This allows the panel assemblies to
`be used for example to front light an LCD or other display
`such that the display is viewed through the transparent panel
`members.
`
`LG D_000442
`
`LGD_000442
`
`

`
`5,613,751
`
`9
`Although the invention has been shown and described
`with respect to certain preferred 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. The present invention includes all such
`equivalent alterations and modifications, and is limited only
`by the scope of the claims.
`What is claimed is:
`
`1. A light emitting panel assembly comprising a light
`emitting panel member having a light emitting surface, a
`light transition area, and a light source embedded or potted
`in said light
`transition area so as to eliminate any air
`interface between said light source and said light transition
`area.
`
`10
`
`2. The assembly of claim 1 further comprising a pattern of
`light extracting deformities on said panel member for pro-
`viding a desired light output distribution.
`3. The assembly of claim 2 wherein said pattern of light
`extracting deformities comprises a plurality of deformities,
`each having an area of no more than approximately 0.006
`square inch.
`4. The assembly of claim, 3 wherein said plurality of
`deformities vary along the length of said light emitting
`surface.
`
`5. The assembly of claim 3 wherein said plurality of
`deformities vary along the width of said light emitting
`surface.
`
`6. The assembly of claim 3 wherein said plurality of
`deformities vary along the width and length of said light
`emitting surface.
`7. The assembly of claim 2 further comprising an end
`reflector at an end of said panel member remote from said
`light source, said pattern of light extracting deformities
`varying to compensate for light reflected back within said
`panel member by said end reflector.
`8. The assembly of claim 2 further comprising a film for
`diffusing the light output distribution from said light emit-
`ting surface.
`9. The assembly of claim 2 wherein said pattern of light
`extracting deformities vary to compensate for a difiuser,
`lens, prismatic surface, label, overlay, colored film, or polar-
`izer used with said panel member.
`10. The assembly of claim 2 wherein said deformities
`comprise prismatic surfaces, raised surfaces or depressions
`formed in said panel member.
`11. The assembly of claim 2 wherein said deformities
`comprise prismatic surfaces formed on an exterior surface of
`said panel member.
`12. The assembly of claim 1 further comprising a film for
`diifusing the light output distribution from said panel mem-
`ber, said film being attached to said panel member around a
`peripheral edge of said panel member, leaving an air gap
`between said panel member and said film.
`13. The assembly of claim 1 furthe