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`US 20050212405A1
`
`(54) SEMICONDUCTOR LIGHT EMITTING
`DEVICES INCLUDING FLEXIBLE FILM
`HAVING THEREIN AN OPTICAL ELEMENT,
`AND METHODS OF ASSEMBLING SAME
`
`Publication Classification
`
`Int. Cl? ..................................................... HOII, 33/00
`{51}
`(52) US. Cl.
`.......................................... .. 313/502; 313501
`
`Inventor: Gerald H. Negley, Currlmm, NC (US)
`
`{57]
`
`ABS'I‘RACI'
`
`(19] United States
`{12] Patent Application Publication (10) Pub. N0.: US 2005/0212405 A1
`
`Neglcy
`(43) Pub. Date:
`Sep. 29, 2005
`
`US. Patent No. 8,929,965
`
`Correspondence Addmfi:
`Mitchell 5' Bigcl
`Myers Rigel Sibley & Salimgc, PJL
`Box 37428
`Raleigh! NC 27627 (Us)
`
`(21} APPL Nu;
`
`lufsuysgs
`
`(2’;
`
`1.11m];
`
`Man 29' 2004
`
`Sumiuonducmr light emitting tluviccs include a substrate
`having a face, a llcxihlu film that includes lI’Il‘JClIl an Uplical
`clement. on [he lace, and a semiconductor light cmilling
`clement between the substrate and the flexible film and
`cottfigurccl
`l0 cmit light through the optical element Thc
`face can include a cavity lhcrcin, and the semiconductor
`light emitting element may he in the. cavity The IIUXIi'SIB lilm
`cxlcnds (mm the fave buyond the cavity, and thu optical
`cluntenl overlies lhc cavity.
`
`100
`
`Apple Inc.
`APL1014
`
`Apple Inc.
`APL1014
`U.S. Patent No. 8,929,965
`
`001
`
`FITBIT, Ex. 1014
`
`

`

`Patent Application Publication Sep. 29, 2005 Sheet 1 of 3
`
`US 2005/0212405 A1
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`002
`
`FITBIT, Ex. 1014
`
`

`

`Patent Application Publication Sep. 29, 2005 Sheet 2 of 3
`
`US 2005/0212405 A1
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`003
`
`FITBIT, Ex. 1014
`
`

`

`US 2005/0212405 A1
`
`Patent Application Publication Sep. 29, 2005 Sheet 3 of 3
`
`FIG. 13
`
`FIG. 11
`
`1230
`
`004
`
`FITBIT, Ex. 1014
`
`

`

`[0006] Some embodiments of the present invention pro-
`vide semiconductor light emitting devices that
`include a
`substrate having a face, a flexible film that includes therein
`an optical element, on the face, and a semiconductor light
`emitting element between the substrate and the flexible film
`and configured to emit light through the optical element. In
`some embodiments, an optical coupling media, such as
`optical gel, is provider] between the optical element and the
`semiconductor light emitting element.
`In some embodi-
`ments, the [ace includes a cavity therein, and the semicon-
`ductor light emitting element is in the cavity. The flexible
`film extends onto the face beyond the cavity, and the optical
`element overlies the cavity. In some embodiments, an optiw
`cal coupling media is provided in the cavity. Semiconductor
`light emitting devices may be assembled, according to
`various embodiments of the present invention, by mounting
`a semiconductor light emitting element on a substrate face,
`and attaching a flexible film that includes therein an optical
`element
`to the substrate face such that,
`in operation, the
`semiconductor light emitting element emits lights through
`the optical element. An optical coupling media may be
`placed between the semiconductor light emitting element
`and the optical coupling element.
`
`005
`
`SEMICONDUCTOR LIGHT EMITTING DEVICES
`INCLUDING FLEXIBLE FILM HAVING THEREIN
`AN OPTICAL ELEMENT, AND METHODS OF
`ASSEMBLING SAME
`
`FIELD OF THE lNVL’N'l'lON
`
`[0001] This invention relates to semiconductor light emit-
`ting devices and fabricating methods therefor, and more
`particularly to packaging and packaging methods for semi-
`conductor light emitting devices.
`
`BACKGROUND OF THE INVENTION
`
`such as
`light emitting devices,
`[0002] Semiconductor
`Light Emitting Diodes (LEDs) or laser diodes, are widely
`used for many applications. As is well known to those
`having skill in the art, a Semiconductor light emitting device
`includes a semiconductor light emitting element having one
`or more semiconductor layers that are configured to emit
`coherent and/or incoherent light upon energization thereof.
`It
`is also known that
`the semiconductor light emitting
`element generally is packaged to provide external electrical
`connections, heal sinking, lenses or waveguides, environ-
`mental protection and/or other functions for the semicon-
`ductor light emitting device. Packaging may be provided, at
`least in part, by at least partially surrounding the semicon—
`ductor light emitting device with a dome-shaped transparent
`plastic shell,
`
`For example, it is known to provide a two-piece
`[0003]
`package for a semiconductor light emitting device wherein
`the semiconductor light emitting element is mounted on a
`substrate of, for example, alumina, aluminum nitride and/or
`other materials, which include electrical traces thereon, to
`provide external connections for the semiconductor light
`emitting element. A second substrate, which, for example,
`may be silver plated copper, is mounted on the first sub-
`strate, for example using glue, surrounding the semiconduc-
`tor light emitting elemcnl. A lens may be placed on the
`second substrate over the semiconductor light emitting ele-
`ment. Light emitting diodes with two-piece packages as
`described above are described in application Ser. No.
`10/446,532 to Loh, entitled Power Surface Mount Light
`Emitting Die Package, filed May 27, 2003, assigned to the
`assignee ofthe present invention, the disclosure of which is
`hereby incorporated herein by reference in its entirety as if
`set forth fully herein.
`
`It is often desirable to incorporate phosphor into a
`[0004]
`semiconductor light emitting device, to enhance the emitted
`radiation in a particular frequency band and/or to convert at
`least some of the radiation to another frequency band.
`l’hospbors may be included in a semiconductor light emit—
`ting device using many conventional
`techniques.
`In one
`technique, phosphor is coated inside and/or outside the
`plastic shell. In other techniques, phosphor is coated on the
`semiconductor light emitting device itself,
`for example
`using electrophoretic deposition. In still other techniques, a
`drop of a material such as epoxy that contains phosphor
`therein may be placed inside the plastic shell, on the
`semiconductor light emitting device and/or between the
`device and the shell. This technique may be referred to as a
`“glob top”. The phosphor coatings may also incorporate an
`index matching material audior a separate index matching
`material may be provided. LEDs that employ phosphor
`
`US 2005/0212405 A1
`
`Sep. 29, 2005
`
`in US. Pat. Nos.
`for example,
`coatings are described,
`6,252,254; 6,069,440; 5,858,278; 5,813,753; 5,2?7,840; and
`5,959,316.
`
`[0005] Unfortunately, the packaging for a semiconductor
`light emitting device may be costly and, in some cases, more
`costly than the semiconductor light emitting element itself.
`Moreover, the assembly process also may be costly,
`time
`consuming and/or subject to failures.
`
`SUMMMY OF THE. INVENTION
`
`[0007] Many different configurations of optical elements
`may be provided according to various embodiments of the
`present invention. In some embodiments, the optical element
`includes (i.e., comprises) a lens. In other embodiments, the
`optical element includes a prism. In other embodiments, the
`flexible film includes a first face adjacent the substrate and
`a second face remote from the substrate. and the optical
`element includes a first optical element on the first face, and
`a second optical element on the second face, both of which
`are located such that the light emitting element emits light
`through the first optical element and the second optical
`element. In some embodiments, the optical element includes
`phosphor and/or other optical emission enhancing andlor
`converting elements. In still other embodiments, the optical
`element
`includes an optical scattering element. Combina-
`tions and subcombinations of these andror other optical
`elements also may be provided. Moreover, an optical cou-
`pling media may be provided between the optical element
`and the semiconductor light emitting element in any of these
`embodiments.
`
`[0008] Many configurations of the flexible film also may
`be provided according to various embodiments of the
`present invention. For example,
`in some embodiments. at
`least a portion of the flexible film that overlies the cavity is
`transparent to the light, and at least a portion of the flexible
`film that extends onto the face beyond the cavity is opaque
`to the light. In other embodiments, at least a portion of the
`flexible film that overlies the cavity includes a first material
`and at least a portion of the flexible film that extends onto the
`
`005
`
`FITBIT, Ex. 1014
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`

`

`US 2005/0212405 A1
`
`Sep. 29, 2005
`
`BRIEF DESCRIPTION OF THE DRAWINGS
`
`006
`
`[0012] Multiple semiconductor light emitting elements
`and/or optical elements may be incorporated in a semicon-
`ductor light emitting device according to various embodi-
`ments of the present invention. Each semiconductor light
`emitting element may be included in its own individual
`cavity and/or multiple semiconductor light emitting clef
`merits may be included in a single cavity. Moreover, in some
`embodiments, the same phosphor may be included on the
`flexible film for each optical element. In other embodiments,
`different phosphors may be used For example, a first
`phosphor layer and a first semiconductor light entitling
`element may be configured to generate red light, a second
`phosphor layer and a second semiconductor light emitting
`element may be configured to generate blue light, and a third
`phosphor layer and a third semiconductor light emitting
`element may be configured to generate green light. Combi-
`nations and subcombinations of these andior other multiple
`semiconductor light emitting elements and/or multiple opti-
`cal elements also may be provided. Finally, combinations
`and subcombinations of these andlor other optical elements,
`flexible films, phosphor and/or multiple elements may be
`provided7 according to various embodimean of the present
`invention.
`
`t’ace beyond the cavity includes a second material. In still
`other embodiments, the semiconductor light emitting ele-
`ment includes a wire that extends towards and contacts the
`
`flexible film in the cavity, and the flexible film includes a
`transparent conductor in the cavity that electrically connects
`to the wire. Combinations and suboombinations of these
`and/or other configurations of flexible film also may be
`provided.
`
`In other embodiments, an attachment element also
`[0009]
`is provided that is configured to attach the flexible film and
`the substrate to one another. Many conventional attachment
`techniques can be used to provide an attachment element.
`
`Some embodiments of the present invention may
`[0010]
`be configured to incorporate phosphor into the semiconduc-
`tor light emitting device. In some embodiments, phosphor is
`provided on the flexible film between the lens and the
`semiconductor light emitting element.
`In other embodi-
`ments, the lens includes a concave inner surface adjacent the
`semiconductor light emitting element, and the phosphor
`includes a conformal phosphor layer on the concave inner
`surface.
`In yet other embodiments,
`the optical element
`includes a lens that overlies the cavity and protrudes awayr
`from the cavity, the flexible film further includes a protrud—
`ing clement between the lens and the light emitting element
`that protmdes towards the cavity, and a conformal phosphor
`coating is provided on the protruding element. Combina-
`tions and subcombinations of these and/or other configura-
`tions of phosphor also may be provided. Moreover, an
`optical coupling media may be provided between the phos-
`phor and the semiconductor light emitting element in any of
`these embodiments.
`
`in still other embodiments of the present invention,
`[001]]
`the semiconductor light emitting element includes a wire
`that extends towards the flexible substrate. In some of these
`embodiments, the optical element includes a prism that is
`configured to reduce shadowing by the wire, of the light that
`is emitted from the semiconductor light emitting clement.
`
`[0013] FIG. 1 is an exploded cross-sectional view of
`semiconductor light emitting devices and fabrication meth-
`ods therefor, according to various embodiments of the
`present invention.
`
`[0014] FIGS. 2-12 are cross-sectional views of semicon—
`ductor light emitting devices according to various embodi-
`ments of the present invention.
`
`[0015] FIG. 13 is a perspective view of a semiconductor
`light emitting device according to various embodiments of
`the present invention.
`
`DETAILED DESCRIPTION
`
`[0016] The present invention now will be described more
`fully hereinafter with reference to the accompanying draw-
`ings, in which embodiments of the invention are shown. This
`invention may, however, be embodied in many difl'erent
`forms and should not be construed as limited to the embodi-
`ments set forth herein. Rather, these embodiments are pro-
`vided so that this disclosure will be thorough and complete,
`and will fully convey the scope of the invention to those
`skilled in the art. In the drawings, the siZe and relative sizes
`of layers and regions may be exaggerated for clarity. Like
`numbers refer to like elements throughout.
`
`It will be understood that when an element such as
`[0017]
`a layer, region or substrate is referred to as being “on”
`another element, it can be directly on the other element or
`intervening elements may also be present. It will be under-
`stood that if part of an element, such as a surface, is referred
`to as “inner,” it is farther from the outside of the device than
`other parts ofthe element. Furthermore, relative terms such
`as “beneath” or “overlies” may be used herein to describe a
`relationship of one layer or region to another layer or region
`relative to a substrate or base layer as illustrated in the
`figures. It will be understood that these terms are intended to
`encompass different orientations of the device in addition to
`the orientation depicted in the figures. Finally,
`the term
`"directly" means that there are no intervening elements. As
`used herein, the term “andlor” includes any and all combi-
`nations of one or more of the associated listed items.
`
`It will be understood that, although the terms first,
`[0018]
`Second, etc. may be used herein to describe various ele-
`ments, components, regions, layers and/or sections, these
`elements, components,
`regions,
`layers andfor sections
`should not be limited by these terms. These terms are only
`used to distinguish one element, component, region, layer or
`section from another region. layer or section. Thus, a first
`region, layer or section discussed below could be termed a
`second region,
`layer or section, and, similarly, a second
`without departing from the teachings of the present inVert—
`lion.
`
`[0019] FIG. 1 is an exploded cross-sectional view of
`semiconductor light emitting devices and assembling meth-
`ods therefor. according to various embodiments of the
`present invention. Referring to FIG. 1, these semiconductor
`light emitting devices 100 include a substrate 110 having a
`face 110a, a flexible film 120 that includes therein an optical
`element 130, on the face 110a, and a semiconductor light
`emitting element 140 between the substrate 110 and the
`flexible film 120, and configured to emit light 160 through
`
`006
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`FITBIT, Ex. 1014
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`

`

`US 2005/0212405 Al
`
`Sep. 29, 2005
`
`007
`
`For example, the light emitting elements 140 may
`[0022]
`be gallium nitride-based LEDs or lasers fabricated on a
`silicon carbide substrate such as those devices manufactured
`and sold by Cree, Inc. of Durham, N.C. The present inven—
`tion may be suitable for use with LEDs andfor lasers as
`described in US. Pat. Nos. 6,201,262; 6,187,606; 6,120.
`600; 5,912,477; 5,739,554; 5,631,190; 5,604,135; 5,523,
`589; 5,416,342; 5,393,993; 5,338,944; 5,210,051; 5,027,
`168'. 5,027,168; 4,966,862 and/or 4,918,497, the disclosures
`ofwhich are incorporated herein by reference as if set forth
`fully herein. Other suitable LEDs andfor lasers are described
`in published US. Patent Publication No. US 2&13/(K106418
`Al entitled Group III Nitride Based Light Emitting Diode
`Structures With a Quantum Well and Superlattice, Group III
`Nitride Based Quantum Well Structures and Group III
`Nitride Based Superlattice Structures, published Jan. 9,
`2003, as well as published US. Patent Publication No. US
`2002/0123164 A1 entitled Light Emitting Diodes Including
`Modifications
`for Light Extraction and Manufacturing
`Methods Therefor. Furthermore, phosphor coated LEDS.
`such as those described in US. application Ser. No. 104659,
`241, entitled Phosphor—Coated Light Emitting Diodes
`Including Tapered Sidewalls
`and Fabrication Methods
`'l’hercfor, filed Sep. 9, 2003,
`the disclosure of which is
`incorporated by reference herein as if set forth fully, may
`also be suitable for use in embodiments of the present
`invention. The LEDs andr‘or lasers may be configured to
`operate such that
`light emission occurs through thc sub-
`strate. In such embodiments, the substrate may be patterned
`so as to enhance light output of the devices as is described,
`for example, in the above-cited US. Patent Publication No.
`US 2002/0123164 A1.
`
`the optical element. An attachment element 150 may be used
`to attach the flexible film 120 and the substrate 110 to one
`another.
`
`the substrate 110 may
`Still referring to FIG. 1,
`[0020]
`include alumina, aluminum nitride, metal and/or other mate-
`rials that are conventionally used for mounting semiconduc-
`tor light emitting elements thereon. In other embodiments.
`the substrate 110 can be a solid metal block, as described in
`copending application Ser. No. IOI659,108 to Negley et al.,
`entitled Solid Metal Block Mounting Substrates for Semi—
`conductor Light Emitting Devices, and oxidizing Methods
`for Fabricating Same, filed Sep. 9, 2003, assigned to the
`assignee of the present invention, the disclosure of which is
`hereby incorporated herein by reference in its entirety as if
`set forth fully herein. The design of substrates 110 are well
`known to those having skill
`in the art and need not be
`described further herein.
`
`[0021] The semiconductor light emitting element 140 may
`include a light emitting diode,
`laser diode andfor other
`semiconductor device which includes one or more semicon—
`ductor layers, which may include silicon, silicon carbide,
`gallium nitride and/or other semiconductor materials, a
`substrate which may include sapphire, silicon, silicon car—
`bide andfor other microelectronic substrates, and one or
`more contact layers which may include metal and/or other
`conductive layers. In some embodiments, ultraviolet, blue
`and/’or green LEDs may be provided. The design and fab-
`rication ofsemiconductor light emitting devices 140 are well
`known to those having skill
`in the art and need not be
`described in detail herein.
`
`Still referring to FIG. 1, the flexible film 120 can
`[0023]
`provide a cover slip that can be made of a flexible material
`such as a conventional Room Temperature Vulcanizing
`(R'I‘V) silicone rubber. Other silicone-based and/or flexible
`materials maybe used. By being made of a flexible material,
`the flexible film 120 can conform to the substrate 110 as it
`expands and contracts during operations. Moreover,
`the
`flexible film 120 can be made by simple low-cost techniques
`such as transfer molding,
`injection molding and/or other
`conventional techniques that are well known to those having
`skill in the art.
`
`[0024] As described above, the flexible film 120 includes
`therein an optical element 130. The optical element can
`include a lens, a prism, an optical emission enhancing andfor
`converting element, such as a phosphor, an optical scattering
`element andior other optical element. One or more optical
`elements 130 also may be provided, as will be described in
`detail below. Moreover, as shown in FIG. 1, an optical
`coupling media 170, such as an optical coupling gel and/or
`other index matching material, may be provided between the
`optical element 130 and the semiconductor light emitting
`device 140, in some embodiments.
`
`[0025] Still referring to FIG. I, the attachment element
`150 can be embodied as an adhesive that may be placed
`around the periphery of the substrate 110, around the periph-
`ery of the flexible film 120 and/or at selected portions
`thereof, such as at the comers thereof. In other embodiments,
`the substrate 110 may be coined around the flexible lilm 120,
`to provide an attachment element 150. Other conventional
`attaching techniques may be used.
`
`1 also illustrates methods of assembling
`[0026] FIG.
`semiconductor light emitting devices 100 according to vari—
`ous embodiments of the present
`invention. As showu in
`FIG. 1, a semiconductor light emitting element 140 is
`mounted on a substrate face 1101A flexible film 120 that
`includes therein an optical element 130 is attached to the
`substrate face 110a, for example using an attachment ele-
`ment 150, such that, in operation, the semiconductor light
`emitting element emits light 160 through the optical element
`130. In some embodiments, an optical coupling media 170
`is placed between the semiconductor light emitting element
`14-0 and the optical element 130.
`
`[0027] FIG. 2 is a cross-sectional view of semiconductor
`light cmitting devices according to other embodiments of the
`present invention. In these embodiments, the substrate face
`110.9 includes a cavity [10b lhet‘ein. The flexible film 120
`extends onto the face 110:: beyond the cavity 1101). The
`optical element 130 overlies the cavity 110b, and the semi-
`conductor light emitting clemenl 140 is in the cavity 110'),
`and is configured to emit
`light 160 through the optical
`element 130. In FIG. 2, the optical element 130 includes a
`concave lens. In some embodiments, an optical coupling
`media 170 is provided in the cavity 1101) between the optical
`element 130 and the semiconductor light emitting element
`140. In some embodiments, the optical coupling media 170
`fills the cavity 11%.
`
`[0028] FIG. 3 is a cross-sectional view of other embodi-
`ments of the present invention. As shown in FIG. 3, two
`optical elements 130 and 330 are included in the flexible film
`120. A first optical element 130 includes a lens and a second
`optical element 330 includes a prism. Light from the semi-
`conductor light emitting element [40 passes through the
`
`007
`
`FITBIT, Ex. 1014
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`

`

`US 2005/0212405 A1
`
`Sep. 29, 2005
`
`008
`
`[0035] FIGS. 10 and 11 illustrate semiconductor light
`emitting devices including multiple semiconductor light
`emitting elements arid/or multiple optical elements accord"
`ing to various embodiments of the present invention. For
`example, as shown in FIG. 10, the optical element 130 is a
`first optical element, and the semiconductor light emitting
`element 140 is a first semiconductor light emitting element.
`The flexible film 120 also includes therein a second optical
`element 130'
`that
`is spaced apart
`from the first optical
`element 130, and the device further includes a second
`semiconductor light emitting element 140' between the
`substrate 110 and the flexible film 120, and configured to
`emit light through the second optical element 130', More-
`over, a third optical element 130" and a third semiconductor
`light emitting element 140” also may be provided. The
`optical elements 130, 130‘ and 130" may be the same and/or
`difl'erent from one another, and the semiconductor light
`emitting elements 140, 140' and 140" may he the same
`andltor diflerent from one another. Moreover,
`in embodi-
`ments of FIG. 10.
`the cavity 110!) is a first cavity. and
`second and third cavities 110b', 1101)", respectively, are
`provided for the second and third semiconductor light emit-
`ting elements 140', 140". respectively. The cavities 1101'),
`1105‘ and llflh'I may be the same and/'or may have different
`configurations from one another. An optical coupling media
`170 also may be provided that may fill the cavity or cavities.
`
`fully cured, so as to provide a satisfactory bond that attaches
`to the second material that is subsequently molded. In other
`embodiments, the same material may be used for the optical
`element and the flexible film, wherein the optical element is
`formed and then the flexible film is formed surrounding the
`optical element. An optical coupling media 170 also may be
`provided that may fill the cavity 110b.
`
`[0033] FIG. 8 is a cross-sectional view of other embodi-
`ments of the present invention. In these embodiments, the
`semiconductor light emitting element 140 includes a wire
`1400, that extends towards and contacts the flexible film 120
`in the cavity 110.5. The flexible film 120 includes a trans-
`parent conductor 810 which can include Indium Tin Oxide
`(ITO) and/or other conventional transparent conductors. The
`transparent conductor 810 extends in the cavity 110th and
`electrically connects to the wire. Reduced shadowing by the
`contact 1405: thereby may be provided. Moreover, a wire
`bond to the substrate 110, and the potential consequent light
`distortion, may be reduced or eliminated. An optical cou—
`pling media 170 also may be provided that may fill the
`cavity 110b.
`
`[0034] FIG. 9 is a cross-sectional view of other embodi-
`ments of the present invention. As shown in FIG. 9, the
`optical element 130 includes a lens that overlies the cavity
`110th and protrudes away from the cavity 1101‘). The flexible
`film 120 further includes a protruding element 930 between
`the lens 130 and the light emitting element 140 that pro-
`trudes towards the cavity 11011 As shown in FIG. 9, a
`conformal phosphor layer 410 is provided on the protruding
`element 930. By providing the protruding element 930 on
`the back of the lens 130, optical coupling media 170 in the
`device may be displaced. Arrangements of FIG. 9 may thus
`provide more uniform phosphor coating at desired distances
`from the light emitting element 140, so as to provide more
`uniform illumination. The optical coupling media 170 may
`fill the cavity 11011
`
`prism 30 and through the lens 130. An optical coupiing
`media 170 also may be provided. In some embodiments, the
`optical coupling media 170 fills the cavity 11%. The optical
`coupling media 170 may have a sufficient difference in index
`of refraction difference from the prism such that the prism
`can reduce shadowing. As shown in FIG. 3, the semicon-
`ductor light emitting element
`includes a wire 140ar
`that
`extends towards the flexible film 120, and the prism 330 is
`configured to reduce shadowing by the wire 140:: of the light
`that is emitted from the semiconductor light emitting ele-
`ment 140. More uniform light emissions thereby may be
`provided, with reduced shadowing ol‘ the wire 140a. It will
`be understood that the term "wire" is used herein in a generic
`sense to encompass any electrical connection for the semi-
`conductor Iight emitting element 140.
`
`[0029] FIG. 4 is a cross-sectional view of other embodi-
`ments of the present invention. As shown in FIG. 4, phos-
`phor 410 is provided on the flexible film 120 between the
`lens 130 and the semiconductor light emitting element 140.
`The phosphor 410 can include cerium-doped Yttrium Alu-
`minum Garnet (YAG) andtor other conventional phosphors.
`In some embodiments,
`the phosphor comprises Cesium
`doped Yttrium Aluminum Garnet
`(YAGICe),
`In other
`embodiments, nano-phosphors may be used. Phosphors are
`well known to those having skill in the art and need not be
`described further herein. An optical coupling media 170 also
`may be provided that may fill the cavity 110b.
`
`[0030] FIG. 5 illustrates yet other embodiments of the
`present
`invention.
`In these embodimean,
`the lens 130
`includes a concave inner surface IJ'lln adjacent the semi-
`conductor light emitting element 140. and the phosphor 410
`includes a conformal phosphor layer on the GORGEVe inner
`surface [30.11. An optical coupling media 170 also may be
`provided that may fill the cavity llflb.
`
`[0031] FIG. 6 is a cross-sectional view of other embodi-
`ments. As shown in FIG. 6, at least a portion 120.41I of the
`flexible film 120 that overlies the cavity 110!) is transparent
`to the light. Moreover, at least a portion 120C of the flexible
`lilm 120 that extends onto the face 110:: beyond the cavity
`110th is opaque to the light, as shown by the dotted portions
`1200 of the flexible film 120. The opaque regions 120C can
`reduce or prevent bouncing of light
`rays, and thereby
`potentially produce a more desirable light pattern. An optical
`coupling media 170 also may he provided that may till the
`Cavity 110b.
`
`[0032] FIG. 7 is a cross-sectional view of other embodi-
`merits of the present invention wherein the flexible film 120
`maybe fabricated of multiple materials. As shown in FIG.
`7, at least a portion 120d of the flexible film 120 that overlies
`the cavity 110th includes a first material, and at least a portion
`120C of the flexible film 120 that extends onto the face 110n
`beyond the cavity ll0b includes a secoan material. Two or
`more materials may be used in the flexible film 120 in some
`embodiments,
`to provide difierent characteristics for the
`portion of the flexible film 120 through which light
`is
`emitted and through which light is not emitted. Multiple
`materials may be used for other purposes in other embodi-
`ments. For example, an inflexible andfor flexible plastic lens
`may be attached to a flexible film. Such a flexible film 120
`with multiple materials may be fabricated using conven—
`tional multipie molding techniques, for example. In some
`embodiments, the first material that is molded may not be
`
`008
`
`FITBIT, Ex. 1014
`
`

`

`US 2005/0212405 A1
`
`Sep. 29, 2005
`
`(Tonventionally, LED packages use a lens molded
`[0043]
`from rigid plastic or glass. Either a hard encapsulant is used
`to encapsulate the chip and form the optical element. or a
`lens is applied upon an optical coupling media, such as an
`optical gel, for example Nye optical gel. The hard encap—
`sulant may be plagued by optical degradation and high stress
`on LED chips, and power LEI) chips in particular, and the
`optical coupling media may also potentially create problems
`because this gel may be exposed on the surface of the part
`which may result in trapping of dust/debris on the exposed
`material due to the stickiness of the gel In contrast, flexible
`films 120 according to some embodiments of the present
`invention can be the terminating surface of the package
`using an optical coupling media 170, and also includes the
`optical elements 130, such as one or more optical lens. The
`ability to place one unit (the flexible film with multiple
`optical elements) can potentially provide a benefit when
`using a package that has multiple LEDs in it. Instead of
`placing a lens for each LED,
`the single placement of a
`flexible film 130 can be provided.
`
`009
`
`[0036] As also shown in FIG. 10, the phosphor 410 may
`be a first phosphor layer, and second andfor third phosphor
`layers 410‘ and 410", respectively, may be provided on the
`flexible film 120 between the second optical element 130'
`and the second semiconductor light emitting element 140‘,
`and between the third optical element 130‘ and the third
`semiconductor light emitting element 140“, respectively.
`The phosphor layers 410'. 410', 410“ may be the saute, may
`be different andlor may be eliminated. In particular, in some
`embodiments of the present invention, the first phosphor
`layer 410 and the first semiconductor light emitting element
`140 are configured to generate red light, the second phos—
`phor layer 410' and the second semiconductor light emitting
`element 140' are configured to generate blue light, and the
`third phosphor layer 410" and the third semiconductor light
`emitting element 140“ are configured to generate green light.
`A Red, Green, Blue (RGB) light emitting element that can
`emit white light thereby may be provided in some embodi-
`rnents.
`
`[0037] FIG. 11 is a cross-sectional view of other embodi-
`ments of the present invention. in these embodiments, a
`single cavity 1100 is provided [or the first, second and third
`semiconductor light emitting elements 140, 140' and 140".
`respectively. An optical coupling media 170 also may be
`provided that may fill the cavity 1100.
`
`[0038] FIG. 12 is a cross-sectional view of yet other
`embodiments of the present
`invention.
`In FIG. 12,
`the
`optical eicment 1230 comprises a lens having phosphor
`dispersed therein. Lenses including phosphor dispersed
`therein are described, for example, in application Ser. No.
`10/659,240 to Negley et al., entitled Transmissivc Optical
`Elements Including Transparent Plastic Shell Having a
`Phosphor Dispersed Therein, and Methods of Fabricating
`Same, filed Sep. 9, 2003, assigned to the assignee of the
`present invention, the disclosure of which is hereby incor-
`porated herein by reference in its entirety as if set forth fully
`herein. Ari optical coupling media 170 also may be provided
`that may fill the cavity llflb.
`
`In still other embodiments ofthe present invention,
`[0039]
`an optical scattering element may be embedded in the lens
`as shown in FIG. 12, andt'or provided as a separating layer
`as show