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`US 20020113244Al
`
`(19) United States
`(12) Patent Application Publication
`Barnett et al.
`
`(10) Pub. No.: US 2002/0113244 Al
`Aug. 22, 2002
`( 43) Pub. Date:
`
`(54) HIGH POWER LED
`
`(52) U.S. Cl .
`
`.............................................. 257/98; 257/432
`
`(76)
`
`Inventors: Thomas J. Barnett, Columbus, OH
`(US); Sean P. Tillinghast, Bexley, OH
`(US)
`
`(57)
`
`ABSTRACT
`
`Correspondence Address:
`James R. Eley, Esq.
`Thompson Hine LLP
`Suite 700
`10 W. Broad St.
`Columbus, OH 43215-3435 (US)
`
`(21) Appl. No.:
`
`10/073,731
`
`(22) Filed:
`
`Feb. 11,2002
`
`Related U.S. Application Data
`
`(60) Provisional application No. 60/270,572, filed on Feb.
`22, 2001.
`
`Publication Classification
`
`(51)
`
`Int. Cl.7
`
`..................................................... HOlL 33/00
`
`A method and system are taught for a system comprising an
`LED package. The LED package may comprise an anode, a
`cathode coupled to the anode, an LED die coupled to the
`cathode and the anode, a lens coupled to the anode, and a
`viscous or silicone material located in a cavity defined by the
`lens, the cathode, and the anode. The viscous or silicone
`material may be a gel, a grease, a non-resilient material, or
`a non-liquid material. The method and system may further
`comprise a mounting device, wherein the lens is mechani(cid:173)
`cally coupled to the mounting device in a socket, bayonet, or
`screwing like fashion. The method and system may further
`comprise an anode strip comprising an array of anodes
`utilized to form an array of the LED packages and a carrier
`strip comprising receiving devices to receive the array of
`LED packages. A portion of the lens may either be coated
`with or comprise light excitable material or the viscous
`material may comprise light excitable material, such that the
`system emits white light.
`
`22
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`PETITIONERS, Ex. 1019
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`

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`Patent Application Publication Aug. 22, 2002 Sheet 1 of 12
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`US 2002/0113244 Al
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`Patent Application Publication Aug. 22, 2002 Sheet 3 of 12
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`Patent Application Publication Aug. 22, 2002 Sheet 4 of 12
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`Patent Application Publication Aug. 22, 2002 Sheet 5 of 12
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`Patent Application Publication Aug. 22, 2002 Sheet 6 of 12
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`Patent Application Publication Aug. 22, 2002 Sheet 8 of 12
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`Patent Application Publication Aug. 22, 2002 Sheet 9 of 12
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`Patent Application Publication Aug. 22, 2002 Sheet 10 of 12
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`PETITIONERS, Ex. 1019
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`Patent Application Publication Aug. 22, 2002 Sheet 11 of 12
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`US 2002/0113244 Al
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`PETITIONERS, Ex. 1019
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`Patent Application Publication Aug. 22, 2002 Sheet 12 of 12
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`US 2002/0113244 Al
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`PETITIONERS, Ex. 1019
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`US 2002/0113244 Al
`
`Aug. 22, 2002
`
`1
`
`HIGH POWER LED
`
`RELAfED APPLICATIONS
`
`[0001] This application claims priority under 35 U.S.C. §
`119( e) as being based on U.S. Provisional Patent Application
`60/270,572 filed Feb. 22, 2001 entitled "High Power LED
`Package."
`
`FIELD
`
`[0002] The embodiments relate generally to packaging for
`use in manufacturing light emitting diodes (LED), and the
`like, that may provide greater light output and increased
`reliability. One aspect of the embodiments may be to pro(cid:173)
`duce an optically efficient LED that can generate a higher
`degree of illumination per unit area than is currently avail(cid:173)
`able in the art. Another aspect of the embodiments may be
`to provide a means of mechanically attaching the device to
`a light fixture or printed circuit board. Another aspect of the
`embodiments may be to provide an improved package for
`LEDs and a method for packaging multiple LEDs on strips,
`which better facilitates automated manufacturing methods
`for assemblies utilizing the LEDs. Another aspect of the
`embodiments may be to provide a means of producing a
`white light. Another aspect of the embodiments may be to
`provide a means of mounting multiple LED dice.
`
`PRIOR ART
`
`[0003] The art of manufacturing the light emitting com(cid:173)
`ponent of LEDs is widely described in the art and well
`known to those so skilled. Furthermore, the art of producing
`white LEDs is well known and described in the art. Pertinent
`patents include: U.S. Pat. No. 5,813,752 issued to Singer et
`al. on Sep. 29, 1998, entitled "UV/Blue LED-Phosphorus
`Device With Short Wave Pass, Long Wave Pass Band Pass
`and Peroit Filters," which describes the use of a layered
`blue/UV LED semiconductor having a top layer of phosphor
`and filters for producing white light; U.S. Pat. Nos. 5,998,
`928 and 6,060,440 issued to Shimizu et al. on Dec. 7, 1999
`and May 20, 2000, respectively and each entitled "Light
`Emitting Device Having A Nitride Compound Semiconduc(cid:173)
`tor And A Phosphor Containing A Garnet Fluorescent Mate(cid:173)
`rial," which describe the design of white LEDs that utilize
`blue LEDs to excite a layer of phosphor material comprising
`garnet fluorescent materials activated with cerium and/or
`including the use of dispersing materials surrounding the
`phosphor containing components to diffuse the resulting
`illumination.
`
`[0004] The structural makeup of various LED packages
`are also disclosed in the commercial data sheets of a number
`of LED manufacturers, see for example, the technical data
`sheets for Super Flux LEDs, by LumiLeds (a joint venture
`between Philips Lighting and Agilent Technology);
`SnapLED 150 LEDs, by LumiLeds; Six LED High Mount
`Stop Light Array, by LumiLeds; Luxeon Star, by LumiLeds;
`Shark Series, High Flux LED Illuminators, by Opto Tech(cid:173)
`nology, Inc.
`
`BACKGROUND
`
`[0005] A light emitting diode (LED) is a compact semi(cid:173)
`conductor device that generates light of various colors when
`a current is passed through it. The color depends primarily
`upon the chemical composition of the light emitting com-
`
`ponent, or chip, of the LED die. LEDs exhibit various
`advantages over filament based lighting devices such as
`longer life, lower power requirements, good initial drive
`characteristics, high resistance to vibration and high toler(cid:173)
`ance to repeated power switching. Because of these favor(cid:173)
`able characteristics LEDs are ,videly used in such applica(cid:173)
`tions as indicators and lower power lighting applications.
`
`[0006] Recently LEDs for red, green and blue (RGB)
`having high luminance and efficiencies have been developed
`and employed in large screen LED displays. This type of
`LED display can be operated with less power and has
`favorable characteristics as being lightweight and exhibiting
`long life. The application for use of LEDs as alternative light
`sources is burgeoning.
`
`[0007] Even in light of its positive characteri5tics, since
`the device is not 100% efficient at generating light from the
`supplied electrical current, a great deal of heat can be
`produced by the LED chip. Therefore, heat sinks are
`employed to dissipate heat generated by the LED, usually
`provided through the metal lead frame of the LED itself. If
`the heat is not adequately dissipated, stress is imposed on
`various internal components of the LED due to differing
`coefficients of thermal expansion. Some manufacturers have
`produced more powerful LEDs having large heat sinks but
`at a trade-off. First, if a LED with a large heat sink is
`soldered using conventional methods (i.e. wave solder,
`reflow solder), the heat from the soldering process is trans(cid:173)
`ferred to the LED chip, which may cause failure of the LED.
`Second, if the LED is soldered using non-conventional
`techniques (i.e. bar soldering or laser soldering), this must
`generally be performed by the LED manufacturer due to the
`heat sensitive nature of the process. Therefore, the LED
`manufacturer provides a high flux LED as a "board level"
`component. Unfortunately, such a configuration may not
`the physical space requirements of the
`accommodate
`intended end product design.
`
`[0008]
`In addition, optical coupling of the LED to an
`associated lens is inefficient. Generally, an LED consists of
`a semiconductor chip potted into place on a substrate using
`an optically clear epoxy. This direct interface of the chip
`(index of refraction n""3.40) to the epoxy (n,,,1.56) creates a
`dramatic index of refraction gradient between the two mate(cid:173)
`rials. As light travels from a medium of high index of
`refraction to low index of refraction, Fresnel losses are
`experienced due to the inability of the light to escape the
`package caused by internal reflection. Therefore, a material
`or a layer of material that minimizes the transition in index
`of refraction will decrease the Fresnel losses that would
`otherwise occur. By substituting the clear epoxy with one or
`more layers of an optical gel or fluid (hereinafter, collec(cid:173)
`tively referred to as a "gel") having an index of refraction
`value midway between the LED chip material and the epoxy,
`photon extraction, and thus light output, v,rill be enhanced.
`
`[0009] Furthermore, because the epoxy used to encapsu(cid:173)
`late the conventional LED chip is generally rigid when fully
`cured, thermal expansion can cause a degree of shear and
`tensile stress on the bond(s) between the wire and LED chip.
`By encapsulating the chip and wire bond in a gel instead of
`an epoxy, the wire bonds are enabled some movement within
`the gel under normal operating conditions, thereby lessening
`the shear and stresses between the chip and the ,vire bond(cid:173)
`ing.
`
`PETITIONERS, Ex. 1019
`
`

`

`US 2002/0113244 Al
`
`Aug. 22, 2002
`
`2
`
`[0010] Finally, when incorporated into various product
`applications, LEDs (in their numerous package designs) are
`generally designed to be assembled onto a printed circuit
`board and secured using a soldering process. However, since
`the LED package of the present invention can be assembled
`using an alternative mechanical process (i.e., pin & socket,
`laser-welding, etc.), the use of LEDs is more flexible for
`automated manufacturing processes, utilizes less board
`space than previously required and can accommodate a
`wider variety of product applications. Mechanical attach(cid:173)
`ment of the LED package of the present embodiments will
`greatly reduce or even eliminate altogether the heat to which
`the LED chip is exposed during the LED assembly process,
`thereby eliminating a major source of component failure. In
`addition, the LED is provided with an integral metal lead
`frame providing substantial greater heat sinking than that
`provided by conventional LEDs coupled to an epoxy printed
`circuit board.
`
`SUMMARY
`
`[0011] One embodiment provides a system comprising an
`LED package. The LED package comprises an annular
`anode and a cathode coupled to the annular anode. The LED
`package also comprises an LED die coupled to the cathode
`and the annular anode and a lens coupled to the annular
`anode. The LED package also comprises a viscous material
`located in a cavity defined by the lens, the cathode, and the
`annular anode.
`
`[0012] Another embodiment provides a system compris(cid:173)
`ing a mounting device and an LED package. The LED
`package comprises an annular lead frame with a central
`opening, a heat sink coupled to the lead frame adjacent the
`central opening, an LED die coupled to the heat sink and via
`wire bonding to the lead frame, and a lens coupled to the
`lead frame. The lens comprises protrusions that are utilized
`to mechanically secure the LED package to the mounting
`device. The LED package further comprises silicone mate(cid:173)
`rial located in a cavity defined by the lens, the heat sink, and
`the lead frame.
`
`[0013] Another embodiment provides a method for mak(cid:173)
`ing a system with an LED package. The making of the LED
`package compri..-,ing the steps of a) providing a heat sink
`with a die cup, b) providing an annular lead frame with a
`concentric opening that receives the heat sink, c) coupling an
`LED die to the die cup of the heat sink, d) coupling the LED
`die, via wire bonding, to the lead frame through the con(cid:173)
`centric opening, e) dispensing a viscous material into a
`cavity defined by the lens, the lead frame, and the heat sink,
`and f) coupling a lens to the lead frame.
`
`[0014] Another embodiment provides a system compris(cid:173)
`ing an LED package. The LED package comprises an
`annular anode and a cathode coupled to the annular anode
`The LED package also comprises an LED die coupled to the
`cathode and the annular anode and a lens coupled to the
`annular anode. The LED package also comprises a cavity
`defined by the lens, the cathode, and the annular anode.
`
`[0015] Another embodiment provides a system compris(cid:173)
`ing an LED package. The LED package comprises an anode
`and a cathode coupled to the anode. The LED package also
`comprises an LED die coupled to the cathode and the anode
`and a lens coupled to the anode. The LED package also
`
`comprises a viscous material located in a cavity defined by
`the lens, the cathode, and the anode.
`[0016] Another aspect may be that the viscous or silicone
`material is a gel, a grease, a non-resilient material, or a
`non-liquid material.
`[0017] Another aspect may be that the system comprises a
`mounting device, where the LED package is mechanically
`coupled to the mounting device via the lens.
`[0018] Another aspect may be that the system further
`comprises an anode strip comprising an array of anodes
`utilized to form an array of the LED packages and a carrier
`strip comprising receiving devices to receive the array of
`LED packages.
`[0019] Another aspect may be that a portion of the lens is
`either coated with or comprises light excitable material such
`that the system emits white light. Another aspect may be that
`the silicone or viscous material includes light excitable
`material such that the system emits white light.
`[0020] Another aspect may be that a plurality of LED dies
`are used.
`
`BRIEF DESCRIPTION OF THE DRAWINGS
`
`[0021] Further features of the present invention will
`become apparent to those skilled in the art to which the
`present embodiments relate from reading the following
`specification and claims, with reference to the accompany(cid:173)
`ing drav.,ings, in which:
`[0022] FIG. 1A is a cross sectional view of one embodi(cid:173)
`ment of a LED package;
`[0023] FIG. lB is a cross sectional view of one embodi(cid:173)
`ment of a system;
`[0024] FIG. 2 is an exploded view of one embodiment of
`an LED package;
`[0025] FIG. 3 is a partial cross section view of a section
`of one embodiment of an LED package;
`[0026] FIG. 4 is a perspective view of an anode according
`to several embodiments;
`[0027] FIG. 5 is an illustration of another embodiment of
`a system comprising a printed circuit board and an LED
`package;
`[0028] FIG. 6 is an illustration of another embodiment of
`a system comprising a carrier strip and LED packages;
`[0029] FIG. 7 is an exploded view of another embodiment
`of an LED package with plural LED dies;
`[0030] FIG. SA is a side view of another embodiment of
`an LED package;
`[0031] FIG. SB is a bottom view of the LED package of
`FIG. SA;
`[0032] FIG. 9A is a side view of another embodiment of
`an LED package;
`[0033] FIG. 9B is a bottom view of the LED package of
`FIG. 9A;
`[0034] FIG. 10 is an illustration of another embodiment of
`the system comprising a casing and an LED package; and
`
`PETITIONERS, Ex. 1019
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`

`

`US 2002/0113244 Al
`
`Aug. 22, 2002
`
`3
`
`[0035] FIG. 11 is an illustration of another embodiment of
`the system comprising a carrier array and LED packages.
`
`DESCRIPTION OF THE PREFERRED
`EMBODIMENT
`
`[0036] With reference to FIGS. 1-4, an LED package 10 of
`a system 100 is shown. The LED package 10 of the system
`100 comprises an annular anode 12, a cathode, 14, an LED
`die 16, and a lens 18. Also, a silicone or viscous material 20
`may be located in a cavity 22 defined by the annular anode
`12, the cathode 14, and the lens 18. This viscous material 20
`may be a clear silicone gel or grease, a non-resilient mate(cid:173)
`rial, a non-liquid material, or the like. In other embodiments,
`the cavity 22 may contain a liquid, resilient or solid material
`or may not contain any material.
`
`[0037] The LED die 16 is coupled to a die cup 24 of the
`cathode 14 and to the anode 12 via wire bonding 26. The
`LED die 16 may be coupled by a thermally and electrically
`conductive epoxy or the like to the die cup 24. The die cup
`24 may have reflective surfaces. The cathode 14 is coupled
`to the anode 12 through use of a coupling material 28, which
`may be liquid crystal polymer, or the like, so long as the
`material is thermally conductive and electrically insulating.
`After dispensing the viscous material 20 into the cavity 22,
`the lens 18 is coupled to the anode 12 via complementary
`coupling devices 30 (see FIG. 3), which may be barbs or
`anode retention tabs, and coupling devices 31 (see FIG. 3),
`which may be receiving openings. The lens 18 further
`comprises protrusions 32, which may be lens feet, that allow
`the LED package 10 to be removeably secured in a coupling
`device 36 of the mounting device 54 in a socket like fashion,
`where the feet 32 are biased against the coupling device 36
`via flexible extensions 34 extending from a peripheral
`portion of the anode 12. Alternatively, as seen in FIGS. 9-10,
`the socket device may be incorporated directly in a light
`fixture to eliminate the need for secondary coupling devices
`and printed circuit boards. After being removeably secured
`in the mounting device 54, extensions 55 extending from the
`mounting device 54 are received in openings 56 in a printed
`circuit board (PCB) 40 and extension 57 extending from the
`mounting device 54 is received in opening 58 in the PCB 40
`to couple the mounting device 54 to the PCB 40. Within the
`mounting device 54, an opening 59 receives the cathode post
`60.
`
`[0038] The annular anode 12 is central to the system 100.
`The annular anode 12 is a lead frame for the LED system
`100. As best seen in FIG. 4, in the circular embodiment
`shown, the annular lead frame 12 somewhat resembles an
`inverted pie pan having a centralized, preferably concentric
`window 50 formed in the "bottom"52 providing access to
`the LED die 16 and wire bonding 26, and through which
`light emitted from the LED die 16 is distributed to the lens
`18. However, other embodiments contemplate other gener(cid:173)
`ally symmetrical shapes, which are equally well suited as
`lead frames, as is the annular embodiment. As discussed
`above, in an embodiment the stamped barbs 30 are formed
`about the periphery of a body of the lead frame 12 for
`captive engagement between the lead frame 12 and the
`receiving openings 31 of the lens 18 during assembly of the
`LED package 10.
`
`[0039] The LED package 10 also allows for significant
`improvement in the product assembly process. Since the
`
`circular LED package 10 is not orientation-specific, it may
`be mounted in the mounting device 54 on the PCB 40, or as
`seen in FIG. 10 the LED package 10 may be mounted in
`mounting device 254 in a light illumination device 200, or
`as seen in FIG. 11 the LED package 10 may be mounted in
`a mounting device 354 in an light fixture assembly 300,
`where in any of these embodiments the LED package 10 is
`mounted in any orientation, radially about its center. This
`eliminates the need for specific component orientation prior
`to assembly. The embodiment shm.vn in FIGS. 1-5 may
`resemble an RCA-type plug that allows the LED package 10
`to be easily installed into the coupling device 36 in the
`mounting device 54 in a socket like fashion without the need
`for heat or any specialized tools.
`[0040] The annular form of the lead frame 12 is further
`designed to provide a large surface area for sinking heat
`generated during use. The shape has the still further benefit
`of reducing thermal expansion due to hoop stresses inherent
`with the annular geometry.
`[0041] Other embodiments of the LED package 10 utilize
`multiple LED dies 16, such as the embodiment shown in
`FIG. 7, which may include a red, green, and blue LED die
`16. In some of these embodiments, each of the LED dies 16
`must be coupled via the wire bonding 26 to different
`segments of the lead frame 12 to provide a separate anode
`segment 12A-C for each LED die 16. With the annular
`configuration of the embodiments, multiple wire bonding 26
`from the lead frame 12 to the multiple LED dies 16 can be
`easily accommodated.
`
`[0042] Finally, the lead frame 12 may be laser welded,
`rather than soldered, or otherwise mechanically coupled to
`the PCB 40 to provide electrical contact between the LED
`package 10 and the PCB 40, thereby minimizing the risk of
`overheating the LED die 16 during assembly of the LED
`package 10 into a product or subassembly.
`
`[0043] The LED package 10 utilizes a lens 18, which may
`be premolded and may be constructed of any one of a
`number of known materials, which may be epoxy resin, urea
`resin, silicon resin, acrylic resin, glass, or the like, in various
`lens patterns or geometries. While shown in a circular
`embodiment, the shape of the lens 18 may be any generally
`symmetrical shape such as, without limitation, square, hex(cid:173)
`agonal, triangular and the like. The lens 18 provides the
`optical pattern for the LED package 10, and may be con(cid:173)
`figured as a convex, concave, or collimating lens and may be
`optically clear or contain dispersants to diffuse the outputted
`light. In several embodiments, the inside surface of the lens
`18 may be coated with a suitable light excitable material or
`the lens 18 may compri5e a suitable light excitable material,
`which may be a phosphor material, for generating white
`light when excited with a blue, ultraviolet, or other color
`LED die 16. In other embodiments, the silicone or viscous
`material 20 may comprise the light excitable material. In
`addition, the lens 18 both partially defines the cavity 22 for
`the viscous material 20 and acts as a protective shield for the
`LED die 16 and attendant wire bonding 26. By premolding
`the lens 18, the optical output of the LED package 10 is
`easily modified by producing a different configuration, pat(cid:173)
`tern, or geometry of the lens 18.
`
`[0044] The viscous material 20 may be an optical quality
`gel or grease or other viscous material, which may have a
`refractive index of n=l.70 or greater. The viscous material
`
`PETITIONERS, Ex. 1019
`
`

`

`US 2002/0113244 Al
`
`Aug. 22, 2002
`
`4
`
`20 is contained in the lens 18 to possibly provide gradual
`transition of index of refraction between the LED die 16,
`which may have an index of refraction about n,.,3.40, and the
`lens 18, which may be have an index of refraction of about
`n""l.5. If the viscous material 20 is an optical gel it may be
`of the type manufactured by Nye Optical. In addition, the
`viscous material 20 reduces the stress on the wire bond 26
`and LED die 16 caused by thermal expansion. In one
`embodiment, the viscous material 20 is formed so that it has
`varying indexes of refraction by arranging it in layers within
`the lens 18, where the layer having the highest index of
`refraction is closest to the LED die 16. In addition to
`facilitating assembly of the LED package 10, the varying
`layers of viscous material 20 between the LED die 16 and
`the lens 18 also lessens the Fresnel losses within the LED
`package 10.
`[0045] As previously discussed, in some embodiments a
`white emitted or output light is produced using a blue,
`ultraviolet, or other color LED die 16 by exciting light
`excitable materials, which may be fluorescent materials, that
`may be located in or on the lens 18, or similar to what is
`disclosed in Shimizu et al. in U.S. Pat. Nos. 5,998,925 and
`6,069,440, the viscous material 20 may contain a suitable
`phosphor material. However, unlike the Shimizu et al.
`patents, in some embodiments one or more layers of the
`viscous material 20 replaces the prior art cured epoxy
`coating resin. In addition, in other embodiments, rather than
`being confined to the cavity 22 holding the LED die 16, the
`phosphor bearing viscous material 20 fills the cavity 22 of
`the entire lens 18, which is more effective for converting
`more of the excitation output into white light. In the circular
`embodiment shown in the figures, the semispherical con(cid:173)
`figuration of the phosphor bearing viscous material 20 also
`provides more of an omni-directional output than the LEDs
`generally depicted by Shimizu et al.
`
`[0046] The wire bonding 26 used to connect the lead
`frame 12 to the LED die 16 may be gold, but may also be
`made from copper, platinum, aluminum or alloys thereof.
`The diameter of the wire bonding 26 is typically in the area
`from 10-45 µm. As recognized in the art, because of thermal
`expansion coefficients between materials in LEDs made
`according to the prior art methods, wire bonds with diam(cid:173)
`eters less than 25 µm are not recommended because of
`breakage at the bonding point. Accordingly, unlike the prior
`art, the wire bonding 26 is encapsulated in a viscous material
`rather than a hard resin, thus permitting some expansion
`without loss of the electrical bonding. The wire bonding 26
`is connected to the electrode(s) of the LED dies(s) 16 and the
`lead frame 12 by normal ,vire bonding techniques.
`
`[0047] The cathode 14, which may be a copper slug or
`heat sink, is provided at the center of the LED package 10,
`and serves as the cathode for the LED package 10. As
`discussed above, the cathode 14 is configured to have the die
`cup 24 at its uppermost surface, within which the LED die
`16 is mounted. As also discussed above, the liquid crystal
`polymer 28 may be used to couple the cathode 14 into place
`·within the anode 12. The liquid crystal polymer 28 also
`provides a barrier to seal the viscous material 20 in place. In
`addition, because the liquid crystal polymer 28 is thermally
`coupled to the anode 12 it provides for additional heat
`sinking for the LED die 16. The inner surface of the die cup
`24 may be finished with a reflective surface, via plating or
`other means, in order to direct the light emitted from the
`
`LED die 16 in a predetermined manner. The mass of the
`cathode 14 provides superior heat sinking for the LED die 16
`to allow higher power to be applied to the LED die 16,
`resulting in higher lumen output.
`[0048]
`In some embodiments, the cathode 14 may be
`provided with an integral center post 60. When so config(cid:173)
`ured, the LED package 10 can be assembled into a PCB 40
`assembly by normal soldering techniques or, without the use
`of heat, by press fitting the LED package 10 into a comple(cid:173)
`mentary socket arrangement of mounting devices 32 and 36.
`In other embodiments, a base 62 of the cathode 14, when
`there is no integral center post, can be laser welded or
`otherwise mechanically coupled to the anode 12 to provide
`electrical contact. In other embodiments, as seen in FIG. 6,
`each of the cathodes 14 of each of the LED packages 10 may
`be connected to receiving devices 72 on a carrier strip 42,
`where each of the anodes 12 may be connected using an
`carrier strip 70. In other embodiments, as seen in FIGS.
`8A-B, an LED package 410 comprises a cathode 414 with
`a post 460 that comprises protrusions 470 that may be
`coupled to a complementary coupling device in the system,
`which may a bayonet type coupling system. In other
`embodiments, as seen in FIGS. 9A-B, an LED package 510
`comprises a cathode 514 with a post 560 having a threaded
`outer surface 570, which may be coupled to a complemen(cid:173)
`tary coupling device in the system.
`
`[0049] The LED die 16, which may have an index of
`refraction of nss3.40, provides lumen output. The LED die
`16 design and it5 method of manufacture are described in by
`Shimizu and others. The LED die 16 may be a multi-layer
`epitaxial semiconductor structure whose anode and cathode
`are electrically mounted to an inner lead 12 and mount lead
`14, respectively. When energized, the LED die 16 is the
`component that emits light of a wavelength predetermined
`by its chemical makeup. As discussed above, to produce the
`desirable white LED output, multiple colors of LED dies 16,
`such as red, blue, and green, may be combined into a single
`LED package, as seen in FIG. 7. However, in other embodi(cid:173)
`ments a blue, ultraviolet, or other color LED die 16 is used
`to excite a phosphor containing component in the lens 18 or
`silicone or viscous material 22 in order to produce a white
`light. Some prior art devices that have similar functions are
`Singer et al. that teaches the use of a phosphor layer on top
`of a blue LED chip to produce a white LED, Shimizu et al.
`that teaches the use of phosphor materials embedded into a
`resin coating material place over the LED chip, and Shimizu
`et al. that teaches the use of phosphor materials in the
`molded lens surrounding the LED chip.
`
`[0050] As seen in FIG. 6, one embodiment provides an
`array of the anodes 12 that is formed continuously into the
`carrier strip 70, which may be an anode carrier strip, maybe
`by stamping or other conventional means. This configura(cid:173)
`tion facilitates manufacturing of the LED package 10. The
`anode carrier strip 70 also provides for alternate means of
`packaging the LED package 10 into subassemblies. For
`example, the carrier strip 42, which may be a cathode carrier
`strip, containing receiving devices 72 having a common
`cathode may be employed as one assembly. In such an
`application, only one electrical connection to the cathode
`would be necessary. Likewise, the anode carrier strip 70 can
`be configured to have a common anode, in which case an
`entire strip of the LED packages 10 can be easily assembled
`into a product by making only two electrical connections.
`
`PETITIONERS, Ex. 1019
`
`

`

`US 2002/0113244 Al
`
`Aug. 22, 2002
`
`5
`
`The cathode carrier strip 42 and the anode carrier strip 70
`may be periodically scored (shown as dashed lines) along
`their length to enable the cathode carrier strip 42 and the
`anode carrier strip 70 to be in broken into predetermined
`lengths.
`
`[0051] The various embodiments have been described in
`detail with respect to specific embodiments thereof, but it
`will be apparent that numerous variations and modifications
`are possible without departing from the spirit and scope of
`the embodiments as defined by the following claims.
`
`What is claimed is:
`1. A system comprising an LED package, the LED
`package comprising:
`
`an annular anode;
`
`a cathode coupled to the annular anode;
`
`an LED die coupled to the cathode and the annular anode;
`
`a lens coupled to the annular anode; and
`
`a viscous material located in a cavity defined by the lens,
`the cathode, and the annular anode.
`2. The system of claim 1 further comprising a mounting
`device, wherein the LED package is mechanically coupled
`to the mounting device via the lens.
`3. The system of claim 1 wherein the system is a light
`fixture.
`4. The system of claim 1 further compri..-,ing:
`
`an anode strip co