LGE_001282
`
`LG Electronics Ex. 1040
`
`

`
`Patent Application Publication
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`Jan. 22, 2004 Sheet 1 of 13
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`US 2004/0012946 A1
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`LGE_001283
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`LGE_001283
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`

`
`Patent Application Publication
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`Jan. 22, 2004 Sheet 2 of 13
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`US 2004/0012946 A1
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`LGE_001284
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`LGE_001284
`
`

`
`Patent Application Publication
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`Jan. 22, 2004 Sheet 3 of 13
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`US 2004/0012946 A1
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`LGE_001285
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`LGE_001285
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`

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`Patent Application Publication
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`Jan. 22, 2004 Sheet 4 of 13
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`US 2004/0012946 A1
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`73
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`
`72
`
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`LGE_001286
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`LGE_001286
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`

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`Patent Application Publication
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`Jan. 22, 2004 Sheet 5 of 13
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`US 2004/0012946 A1
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`LGE_001287
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`LGE_001287
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`

`
`Patent Application Publication
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`Jan. 22, 2004 Sheet 6 of 13
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`US 2004/0012946 A1
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`LGE_001288
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`LGE_001288
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`

`
`Patent Application Publication
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`Jan. 22, 2004 Sheet 7 of 13
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`US 2004/0012946 A1
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`LGE_001289
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`LGE_001289
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`

`
`Patent Application Publication
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`Jan. 22, 2004 Sheet 8 of 13
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`US 2004/0012946 A1
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`I29
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`22
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`LGE_001290
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`LGE_001290
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`

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`Patent Application Publication
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`Jan. 22, 2004 Sheet 9 of 13
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`US 2004/0012946 A1
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`I25
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`LGE_001291
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`LGE_001291
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`

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`Patent Application Publication
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`Jan. 22, 2004 Sheet 10 of 13
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`US 2004/0012946 A1
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`
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`

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`Patent Application Publication
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`Jan. 22, 2004 Sheet 11 of 13
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`US 2004/0012946 A1
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`LGE 001293
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`LGE_001293
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`

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`Patent Application Publication
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`Jan. 22, 2004 Sheet 12 of 13
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`US 2004/0012946 A1
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`LGE_001294
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`LGE_001294
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`

`
`Patent Application Publication
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`Jan. 22, 2004 Sheet 13 of 13
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`US 2004/0012946 A1
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`LGE_001295
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`LGE_001295
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`

`
`US 2004/0012946 A1
`
`Jan. 22, 2004
`
`LIGHT EMITTING PANEL ASSEMBLIES
`
`CROSS-REFERENCE TO RELATED
`APPLICATIONS
`
`[0001] This application is a continuation of U.S. patent
`application Ser. No. 09/256,275, filed Feb. 23, 1999, which
`is a continuation-in-part of U.S. patent application Ser. No.
`08/778,089, filed Jan. 2, 1997, now U.S. Pat. No. 6,079,838,
`dated Jun. 27, 2000, which is a division of U.S. patent
`application Ser. No. 08/495,176, filed Jun. 27, 1995, now
`U.S. Pat. No. 5,613,751, dated Mar. 25, 1997.
`
`BACKGROUND OF THE INVENTION
`
`[0002] This invention relates generally, as indicated, to
`light emitting panel assemblies.
`
`[0003] Light emitting panel assemblies are generally
`known. However, the present invention relates to several
`different light emitting panel assembly configurations which
`provide for better control of the light output from the panel
`assemblies and more efficient utilization of light to suit a
`particular application. SUMMARY OF THE INVENTION
`
`In accordance with one aspect of the invention, the
`[0004]
`light emitting panel assemblies include a light emitting panel
`member having a pattern of individual
`light extracting
`deformities of well defined shapes on or in one or more
`surface areas of the light emitting panel member.
`
`In accordance with another aspect of the invention,
`[0005]
`each of the light extracting deformities includes a reflective
`or refractive surface of a predetermined slope for more
`precisely controlling the emission of light by each of said
`deformities.
`
`In accordance with another aspect of the invention,
`[0006]
`each of the light extracting deformities has an end wall that
`produces a relatively small projected surface area on the
`panel surface area to allow the number of deformities on or
`in the panel surface areas to be increased.
`
`In accordance with another aspect of the invention,
`[0007]
`the light extracting deformities have straight side walls.
`
`In accordance with another aspect of the invention,
`[0008]
`the light extracting deformities have rounded side walls.
`
`In accordance with another aspect of the invention,
`[0009]
`the light extracting deformities have planar surfaces in
`parallel spaced relation to the panel surface areas.
`
`In accordance with another aspect of the invention,
`[0010]
`the panel member is transparent and includes one or more
`panel portions having opposite sides that are free of any
`reflective material, whereby light is free to pass through such
`opposite sides.
`
`In accordance with another aspect of the invention,
`[0011]
`deformities on or in one or more of the panel portions are
`shaped to cause more of the light entering the panel member
`through an input edge to be emitted from one of the sides of
`the panel portions than the other side.
`
`In accordance with another aspect of the invention,
`[0012]
`the one side of the panel portion through which more of the
`light is emitted may be placed in close proximity to a front
`face of a display for front lighting the display.
`
`LGE_001296
`
`In accordance with another aspect of the invention,
`[0013]
`the light emitting deformities have planar surfaces through
`which light from the display passes with minimal optical
`distortion.
`
`In accordance with another aspect of the invention,
`[0014]
`the pattern of light extracting deformities may be uniform or
`variable as desired to obtain a desired light output distribu-
`tion form the panel surface areas.
`
`In accordance with another aspect of the invention,
`[0015]
`the size and shape as well as the depth or height and angular
`orientation and location of the light extracting deformities
`may vary along the length and/or width of any given panel
`surface area to obtain a desired light output distribution from
`the panel member.
`
`In accordance with yet another aspect of the inven-
`[0016]
`tion, a focused light source may be insert molded or cast
`within a light transition area of the light emitting panel
`member.
`
`In accordance with still another aspect of the
`[0017]
`invention, molded supports may be provided on the panel
`member for supporting other parts or components in spaced
`relation from the panel member.
`
`In accordance with another aspect of the invention,
`[0018]
`an array of light sources may be mounted on a printed circuit
`board for directing light through a diffuser or lens mounted
`in spaced relation to the light sources for use in phototherapy
`treatment and the like.
`
`[0019] The various light emitting panel assemblies of the
`present invention are relatively 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 and/or longer, and/or of various shapes and sizes.
`
`To the accomplishment of the foregoing and related
`[0020]
`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.
`
`BRIEF DESCRIPTION OF THE DRAWINGS
`
`[0021]
`
`In the annexed drawings:
`
`[0022] FIGS. 1 through 3 are schematic perspective
`views of three different forms of light emitting panel assem-
`blies in accordance with this invention;
`
`[0023] 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;
`
`[0024] FIGS. 4b, c and d are enlarged schematic perspec-
`tive views of a portion of a light output area of a panel
`assembly showing other forms of light extracting deformi-
`ties formed in or on the light output area;
`
`[0025] 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;
`
`LGE_001296
`
`

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`US 2004/0012946 A1
`
`Jan. 22, 2004
`
`[0026] FIG. 6 is a schematic perspective view of another
`form of light emitting panel assembly in accordance with
`this invention;
`
`deformities also similar in shape to those shown in FIGS. 28
`and 29 arranged in staggered rows along the length of the
`panel surface areas;
`
`[0027] FIG. 7 is a schematic top plan view of another
`form of light emitting panel assembly in accordance with
`this invention;
`
`[0028] FIG. 8 is a schematic perspective view of another
`form of light emitting panel assembly in accordance with
`this invention;
`
`[0029] FIG. 9 is a schematic top plan view of another
`form of light emitting panel assembly in accordance with
`this invention;
`
`[0030] FIG. 10 is a schematic top plan view of still
`another form of light emitting panel assembly in accordance
`with this invention;
`
`[0031] FIG. 11 is a side elevation view of the light
`emitting panel assembly of FIG. 10;
`
`[0032] 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;
`
`[0033] FIG. 12 is a schematic top plan view of another
`form of light emitting panel assembly in accordance with
`this invention;
`
`[0034] FIG. 13 is a schematic side elevation view of the
`light emitting panel assembly of FIG. 12;
`
`[0035] FIGS. 14 and 15 are schematic perspective views
`of still other forms of light emitting panel assemblies in
`accordance with this invention;
`
`[0043] FIGS. 36 and 37 are enlarged schematic top plan
`views of panel surface areas containing a random or variable
`pattern of different sized light emitting deformities on the
`panel surface areas;
`
`[0044] FIG. 38 is an enlarged schematic perspective view
`of a panel surface area showing light extracting deformities
`in accordance with this invention increasing in size as the
`distance of the deformities from the light source increases or
`intensity of the light increases along the length of the panel
`surface area;
`
`[0045] FIGS. 39 and 40 are schematic perspective views
`showing different angular orientations of the light extracting
`deformities along the length and width of a panel surface
`area;
`
`[0046] FIGS. 41 and 42 are enlarged perspective views
`schematically showing how exemplary light rays emitted
`from a focused light source are reflected or refracted by
`different
`individual
`light extracting deformities of well
`defined shapes in accordance with this invention;
`
`[0047] FIG. 43 is a schematic perspective view showing
`a light emitting panel assembly similar to FIG. 42 placed on
`a front face of a display to provide front lighting for the
`display;
`
`[0048] FIG. 44 is a schematic top plan view of another
`form of light emitting panel assembly in accordance with
`this invention for use in phototherapy treatment and the like;
`and
`
`[0036] FIGS. 16 and 17 are enlarged schematic fragmen-
`tary plan views of a surface area of a light panel assembly
`showing still other forms of light extracting deformities in
`accordance with this invention formed on or in a surface of
`
`[0049] FIGS. 45 through 47 are schematic side elevation
`views of still other forms of light emitting panel assemblies
`in accordance with this invention for use in phototherapy
`treatment and the like.
`
`the panel member;
`
`[0037] FIGS. 18 and 19 are enlarged longitudinal sections
`through one of the light extracting deformities of FIGS. 16
`and 17, respectively;
`
`[0038] FIGS. 20 and 21 are enlarged schematic longitu-
`dinal sections through light extracting deformities similar to
`FIGS. 18 and 19, respectively, except that the deformity end
`walls are shown extending substantially perpendicular to the
`panel surface instead of perpendicular to their respective
`reflective/refractive surfaces as shown in FIGS. 18 and 19;
`
`[0039] FIGS. 22 through 30 are enlarged schematic per-
`spective views of panel surface areas containing various
`patterns of individual light extracting deformities of other
`well defined shapes in accordance with this invention;
`
`[0040] FIG. 31 is an enlarged schematic longitudinal
`section through another form of light extracting deformity in
`accordance with this invention;
`
`[0041] FIGS. 32 and 33 are enlarged schematic top plan
`views of panel surface areas containing light extracting
`deformities similar in shape to those shown in FIGS. 28 and
`29 arranged in a plurality of straight rows along the length
`and width of the panel surface area;
`
`[0042] FIGS. 34 and 35 are enlarged schematic top plan
`views of panel surface areas containing light extracting
`
`DETAILED DESCRIPTION OF THE
`PREFERRED EMBODIMENTS
`
`[0050] Referring now in detail to the drawings, and ini-
`tially 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 predeter-
`mined 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 distribution to fit a particular application.
`
`In FIG. 1 the light transition area 4 is shown as an
`[0051]
`integral extension of one end of the light emitting panel 2
`and as being generally rectangular in shape. However, the
`light transition area may be of other shapes suitable for
`embedding, potting, bonding or otherwise mounting the
`light source. Also, reflective or refractive surfaces may be
`provided to increase efficiency. Moreover, the light transi-
`tion 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
`
`LGE_001297
`
`LGE_001297
`
`

`
`US 2004/0012946 A1
`
`Jan. 22, 2004
`
`efficiently reflect or refract a portion of the light emitted
`from the light source through the light emitting panel at an
`acceptable angle.
`
`[0052] FIG. 2 shows another form of light emitting panel
`assembly 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 efficiently 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.
`
`[0053] 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 invention including two light sources 3. Of course, it
`will be appreciated that the panel assemblies of the present
`invention may be provided with any number of light sources
`as desired, depending on the particular application.
`
`[0054] 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
`and/or faceted surfaces, and if desired, suitable reflective
`materials or coatings may be provided on portions of these
`surfaces to more efficiently reflect and/or refract and focus
`a portion of the light emitted for example from an incan-
`descent 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.
`
`[0055] 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 accom-
`plished, for example, by bonding the light sources 3 in the
`slots, cavities or openings 16 in the light transition areas
`using a sufficient quantity of a suitable embedding, potting
`or bonding material 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).
`
`[0056] Atransparent light emitting material of any suitable
`type, for example acrylic or polycarbonate, may be used for
`the light emitting panels. Also, the panels may be substan-
`tially fiat, or curved, may be a single layer or multi-layers,
`and may have different thicknesses and shapes. Moreover,
`
`LGE_001298
`
`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.
`
`[0057] 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 different 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.
`
`[0058] A pattern of light extracting deformities or disrup-
`tions 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 schemati-
`cally 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
`interchangeably to mean any change in the shape or geom-
`etry 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.
`
`[0059] These deformities or disruptions 21 can be pro-
`duced 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.
`
`[0060] By varying the density, opaqueness or translu-
`cence, 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
`
`LGE_001298
`
`

`
`US 2004/0012946 A1
`
`Jan. 22, 2004
`
`percentage of and/or larger deformities may be placed on
`areas of the panels where greater light output is desired.
`
`[0061] 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.
`
`[0062] 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 back light, the
`light output will be more efficient 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.
`
`[0063] Additionally, the pattern of light extracting defor-
`mities 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 tech-
`niques to vary the deformity 21 coverage. Moreover, the
`pattern of light extracting deformities 21 may be multiple
`layers or vary in index of refraction.
`
`[0064] 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 pat-
`terns 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 par-
`ticular application thereby eliminating the detection of gra-
`dient or banding lines that are common to light extracting
`patterns utilizing larger elements. Additionally, the deformi-
`ties may vary in shape and/or size along the length and/or
`width of the panel members. Also, a random placement
`pattern of the deformities 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
`effect color correction in the panel members. The color of
`the deformities may also vary throughout the panel mem-
`bers, for example to provide different colors for the same or
`different light output areas.
`
`In addition to or in lieu of the patterns of light
`[0065]
`extracting deformities 21 shown in FIG. 4a, other light
`extracting deformities including prismatic surfaces, depres-
`sions or raised surfaces of various shapes using more
`complex shapes in a mold pattern may be molded, etched,
`stamped, thermoformed, hot stamped or the like into or on
`
`LGE_001299
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`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 surfaces may be varied to direct the light in different
`directions to produce a desired light output distribution or
`effect. Moreover, the reflective or refractive surfaces may
`have shapes or a pattern with no specific angles to reduce
`moire or other interference effects.
`
`[0066] 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 efficiency 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 adhe-
`sive 28 or other method in order to produce a desired effect.
`
`[0067] 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
`[0068]
`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 difficulty 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.
`
`[0069] Referring further to FIG. 2, the panel assembly 5
`shown therein also includes molded posts 31 at one or more
`corners 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.
`
`[0070] FIG. 6 shows another form of light emitting panel
`assembly 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
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`LGE_001299
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`US 2004/0012946 Al
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`Jan. 22, 2004
`
`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 reflec-
`tive 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/refrac-
`tive 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.
`
`[0071] 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
`different colors and/or intensities. In this particular embodi-
`ment, 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.
`
`[0072] FIG. 8 shows yet another form of light emitting
`panel assembly 45 in accordance with this invention includ-
`ing 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.
`
`[0073] FIG. 9 schematically shows another form of light
`emitting panel assembly 50 in accordance with this inven-
`tion, including 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 posi-
`tioned 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
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`LGE_001300
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`recess may act as a mold permitting transparent material
`from which the transition area 57 is made to be cast around
`
`one or more light sources 3.
`
`[0074] FIGS. 10 and 11 schematically show another form
`of light emitting panel assembly 60 in accordance with this
`invention including a panel member 61 having one or more
`light output areas 62. In this p