UNITED STATES PATENT AND TRADEMARK OFFICE
`_______________
`
`BEFORE THE PATENT TRIAL AND APPEAL BOARD
`
`_______________
`
`K.J. PRETECH CO., LTD.
`
`Petitioner
`
`v.
`
`INNOVATIVE DISPLAY TECHNOLOGIES LLC
`Patent Owner
`_______________
`
`Case: IPR2015-01867
`
`Patent 7,537,370
`
`DECLARATION OF THOMAS L. CREDELLE
`
`VIZIO EX. 1004
`K.J. Pretech Ex. 1004
`
`Pretech_000311
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`

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`TABLE OF CONTENTS
`
`I.
`
`II.
`
`INTRODUCTION .........................................................................................1
`A.
`Background and Qualifications............................................................1
`B.
`Information Considered .......................................................................5
`Legal Standards .............................................................................................5
`A.
`Person of Ordinary Skill in The Art.....................................................6
`B.
`Anticipation..........................................................................................7
`C.
`Obviousness .........................................................................................8
`D.
`Claim Construction ............................................................................10
`III. Technology Background .............................................................................11
`A.
`Light Emitting Panel Assemblies.......................................................11
`B.
`Common Light Control Structures and Films....................................19
`C.
`Low Loss............................................................................................28
`IV. The ’370 Patent ............................................................................................28
`A.
`Background of The ’370 Patent .........................................................28
`B.
`Prosecution History (Ex. 1002)..........................................................31
`C.
`Asserted Claims .................................................................................34
`D.
`Claim Construction ............................................................................37
`Prior Art Analysis........................................................................................40
`A.
`Claims 1, 4, and 29 are obvious in view of U.S. Patent No. 5,408,388
`(“Kobayashi”) ....................................................................................40
`1.
`Claim 1 ....................................................................................41
`2.
`Claim 4 ....................................................................................55
`3.
`Claim 29 ..................................................................................55
`Claims 13 and 47 are obvious in view of U.S. Patent No. 5,408,388
`(“Kobayashi”) In View of U.S. Patent No. 5,005,108 (“Pristash”)...65
`1.
`Claim 13 ..................................................................................67
`2.
`Claim 47 ..................................................................................72
`i
`
`V.
`
`B.
`
`Pretech_000312
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`C.
`
`Claims 1, 4, 5, 9, 13, 29, and 47 are Obvious in view of Suzuki (Ex.
`1008) ..................................................................................................78
`1.
`Claim 1 ....................................................................................78
`Claims 13 and 47 are Obvious in view of Suzuki and Pristash.......105
`Claims 1, 4-5, 9, and 13 Are Unpatentable Under 35 U.S.C. § 103(a)
`As Being Obvious Over Suzuki in view of Murata.........................118
`SUPPLEMENTATION.............................................................................121
`
`D.
`E.
`
`VI.
`
`ii
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`Pretech_000313
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`

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`I.
`
`1.
`
`INTRODUCTION
`
`My name is Tom Credelle, and I have been retained by the law firm of
`
`Mayer Brown LLP on behalf of K.J. Pretech Co., Ltd. as an expert in the relevant
`
`art.
`
`2.
`
`I have been asked to provide my opinions and views on the materials I have
`
`reviewed in this case related to Ex. 1001, U.S. Patent No. 7,537,370 (“the ’370
`
`Patent”) (“the patent-at-issue”), and the scientific and technical knowledge With
`
`respect to the same subject matter before and for a period following the date of the
`
`first application for the patent-at-issue was filed.
`
`3.
`
`I am compensated at the rate of $350/hour for my work, plus reimbursement
`
`for expenses. My compensation has not influenced any of my opinions in this
`
`matter and does not depend on the outcome of this proceeding or any issue in it.
`
`4.
`
`My opinion and underlying reasoning for this opinion is set forth below.
`
`A.
`
`Background and Qualifications
`
`My full curriculum vitae is attached hereto as Appendix A.
`
`I have more than 40 years of
`
`industry experience in research and
`
`5.
`
`6.
`
`development in the areas of Liquid Crystal Display (LCD) technology and in other
`
`flat panel displays.
`
`7.
`
`I received my M.S. degree in Electrical Engineering from the Massachusetts
`
`Institute of Technology in 1970, with an emphasis on Electro-optics and Solid
`
`1
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`Pretech_000314
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`State Materials. I received my B.S. degree in Electrical Engineering in 1969 from
`
`Drexel University.
`
`8.
`
`I was employed by RCA at Sarnoff Labs in Princeton, NJ from 1970 through
`
`1986 at first as a Member of the technical Staff and later as a Group Manager in
`
`charge of all Active Matrix LCD research. During my time at RCA, I participated
`
`in research and development projects relating to optical materials and flat panel
`
`displays, including LCD devices. In 1983, I established the Thin-Film Transistor
`
`(TFT) LCD Program at Sarnoff Labs. As a Group Manager, I led a project that
`
`resulted in the development of the first poly-Silicon TFT LCD at Sarnoff Labs. I
`
`received the Sarnoff Outstanding Achievement Award for Large-Area Flat Panel
`
`TV Developments.
`
`9.
`
`From 1986 to 1991, I was employed by GE as the Manager of TFT LCD
`
`Research and Development at
`
`the GE Research and Development Center in
`
`Schenectady, NY. My duties included managing research and development efforts
`
`relating to TFT and LCD technology for avionics applications. While employed
`
`by GE, I led the team that built the world’s first 1 million pixel color LCD device.
`
`I also led development of numerous other display devices utilizing LCD
`
`technology. A key part of this effort was the development of high-brightness
`
`backlighting systems for outdoor applications. We succeeded in engineering full
`
`sunlight-readable displays.
`
`2
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`Pretech_000315
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`10.
`
`From 1991 to 1994, I was employed by Apple Computer as the Manager of
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`Display Engineering.
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`In my role at Apple, I supervised all LCD design,
`
`engineering, and qualification for
`
`the first Powerbook notebook computers
`
`introduced to market in the United States. A key part of my effort was the
`
`development of low-power backlighting systems for use in notebook computers.
`
`These designs involved edge lighting systems with various focusing structures and
`
`light extraction patterns to improve uniformity.
`
`11.
`
`From 1994 to 1996, I was employed as the Director of Advanced Product
`
`Marketing by Allied Signal, where I was involved with the design and engineering
`
`of optical films and custom focusing backlight designs for improving the viewing
`
`angle performance of LCD devices.
`
`12.
`
`From 1996 to 1999, I was employed as the Director of Product Marketing
`
`for Motorola’s Flat Panel Display Division, where I worked in the development of
`
`new flat panel technology, and I also worked closely with Motorola groups
`
`responsible for integrating LCD technology into mobile phone products. These
`
`designs exclusively used LED light sources.
`
`13.
`
`From 1999 to 2001, I served as the Vice President of Operations of Alien
`
`Technology Corporation. During my time at Alien Technology, I was involved
`
`with the design and architecture of drive-electronics packaging technology suitable
`
`for flexible LCD devices.
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`3
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`14.
`
`From 2001 to 2007, I served as the Vice President of Engineering for
`
`Clairvoyante, Inc. My responsibilities as the VP of Engineering included
`
`managing research, development, engineering, and marketing of technologies for
`
`improving the resolution and power consumption of color flat panel displays.
`
`During my time at Clairvoyante, I was heavily involved with the design of LCD
`
`driving circuitry and image processing circuitry,
`
`including image processing
`
`algorithms. LED backlights were adapted for use with the new technology
`
`developed by Clairvoyante. My work resulted in the issuance of multiple patents
`
`relating to display technology.
`
`15.
`
`From 2007 to 2008, I served as the Senior VP of Engineering for Puredepth,
`
`Inc. My responsibilities included the design of hardware and software to create 3D
`
`images on LCDs.
`
`16.
`
`From 2012 through 2015, I served as the Vice President of Application
`
`Engineering and Device Performance for Innova Dynamics, Inc., a nanotechnology
`
`company developing materials to be used in LCDs and touch sensors. In 2008, I
`
`founded TLC Display Consulting, a company that provides technical consulting in
`
`the areas of flat panel displays, liquid crystal displays, and related electronics.
`
`I
`
`currently serve as the President of TLC Display Consulting.
`
`17.
`
`I have been a member of the Society for Information Display for over
`
`40 years and have attended and actively participated in every SID Symposium
`
`4
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`Pretech_000317
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`since 1972.
`
`I was a member of the Society for Information Display’s Program
`
`Committee for 15 years, and the Director of the Society for Information Display’s
`
`Symposium Committee for 10 years.
`
`In 1984, I was awarded the title of Society
`
`for
`
`Information Display Fellow in recognition of my achievements and
`
`contributions to flat panel display technology.
`
`18.
`
`I am a named inventor on over 70 patents relating to flat panel display and
`
`LCD technology.
`
`I have also authored a number of articles relating to LCD
`
`technology and flat panel displays that were published by industry periodicals such
`
`as Information Display and peer-reviewed journals such as the Society for
`
`Information Display’s Digest of Technical Papers.
`
`B.
`
`Information Considered
`
`19.
`
`In addition to my general knowledge gained as a result of my education and
`
`experience in this field, I have reviewed and considered, among other things, the
`
`’370 Patent, the prosecution history of the ’370 Patent, the prior art of record, and
`
`the documents listed in the exhibit list.
`
`II.
`
`20.
`
`LEGAL STANDARDS
`
`In forming my opinions and considering the patentability of the claims of the
`
`’370 Patent, I am relying upon certain legal principles that counsel has explained to
`
`me.
`
`21.
`
`I understand that for an invention claimed in a patent to be found patentable,
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`5
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`Pretech_000318
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`it must be, among other things, new and not obvious in light of what came before
`
`it. Patents and publications which predated the invention are generally referred to
`
`as “prior art.”
`
`22.
`
`I understand that in this proceeding the burden is on the party asserting
`
`unpatentability to prove it by a preponderance of the evidence. I understand that “a
`
`preponderance of the evidence” is evidence sufficient to show that a fact is more
`
`likely than not.
`
`23.
`
`I understand that in this proceeding, the claims must be given their broadest
`
`reasonable interpretation consistent with the specification. The claims after being
`
`construed in this manner are then to be compared to information that was disclosed
`
`in the prior art.
`
`A.
`
`Person of Ordinary Skill in The Art
`
`24.
`
`I have been informed that the claims of a patent are judged from the
`
`perspective of a hypothetical construct involving “a person of ordinary skill in the
`
`art.” The “art” is the field of technology to which the patent is related. I
`
`understand that
`
`the purpose of using a person of ordinary skill
`
`in the art’s
`
`viewpoint is objectivity. Thus, I understand that the question of validity is viewed
`
`from the perspective of a person of ordinary skill in the art, and not from the
`
`perspective of (a) the inventor, (b) a layperson, or (c) a person of extraordinary
`
`skill in the art.
`
`I have been informed that the claims of the patent-at-issue are
`
`6
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`Pretech_000319
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`interpreted as a person of ordinary skill in the art would have understood them in
`
`the relevant time period (i.e., when the patent application was filed or earliest
`
`effective filing date).
`
`25.
`
`It is my opinion that a person of ordinary skill in the art relevant to the ’370
`
`patent would have at least an undergraduate degree in physics, optics, electrical
`
`engineering, or applied mathematics AND 3 years of work experience (or a
`
`graduate degree) in a field related to optical technology.
`
`26.
`
`I understand that a “person of ordinary skill is also a person of ordinary
`
`creativity, not an automaton” and that would be especially true of anyone
`
`developing liquid crystal display structures.
`
`B.
`
`Anticipation
`
`27.
`
`I understand that
`
`the following standards govern the determination of
`
`whether a patent claim is “anticipated” by the prior art.
`
`I have applied these
`
`standards in my analysis of whether claims of the ’370 Patent were anticipated at
`
`the time of the invention.
`
`28.
`
`I understand that a patent claim is “anticipated” by a single prior art
`
`reference if that reference discloses each element of the claim in a single
`
`embodiment. A prior art reference may anticipate a claim inherently if an element
`
`is not expressly stated, but only if the prior art necessarily includes the claim
`
`limitations.
`
`7
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`Pretech_000320
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`29.
`
`I understand that the test for anticipation is performed in two steps. First, the
`
`claims must be interpreted to determine their meaning. Second, a prior art
`
`reference is analyzed to determine whether every claim element, as interpreted in
`
`the first step, is present in the reference. If all the elements of a patent claim are
`
`present in the prior art reference, then that claim is anticipated and is invalid.
`
`30.
`
`I understand that it is acceptable to examine extrinsic evidence outside the
`
`prior art reference in determining whether a feature, while not expressly discussed
`
`in the reference, is necessarily present within that reference.
`
`C.
`
`Obviousness
`
`31.
`
`I understand that a claim can be invalid in view of prior art if the differences
`
`between the subject matter claimed and the prior art are such that the claimed
`
`subject matter as a whole would have been “obvious” at the time the invention was
`
`made to a person having ordinary skill in the art.
`
`32.
`
`I understand that the obviousness standard is defined at 35 U.S.C. § 103(a).
`
`I understand that a claim is obvious over a prior art reference if that reference,
`
`combined with the knowledge of one skilled in the art or other prior art references
`
`disclose each and every element of the recited claim.
`
`33.
`
`I also understand that
`
`the relevant
`
`inquiry into obviousness requires
`
`consideration of four factors:
`
`a.
`
`The scope and content of the prior art;
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`8
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`Pretech_000321
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`b.
`
`c.
`
`d.
`
`The differences between the prior art and the claims at issue;
`
`The knowledge of a person of ordinary sill in the pertinent art; and
`
`Objective factors indicating obviousness or non-obviousness may be
`
`present
`
`in any particular case, such factors including commercial success of
`
`products covered by the patent claims; a long-felt need for the invention; failed
`
`attempts by others to make the invention; copying of the invention by others in the
`
`field; unexpected results achieved by the invention; praise of the invention by the
`
`infringer or others in the field; the taking of licenses under the patent by others;
`
`expressions of surprise by experts and those skilled in the art at the making of the
`
`invention; and that the patentee proceeded contrary to the accepted wisdom of the
`
`prior art.
`
`34.
`
`I understand that when combining two or more references, one should
`
`consider whether a teaching, suggestion, or motivation to combine the references
`
`exists so as to avoid impermissible hindsight.
`
`I have been informed that the
`
`application of the teaching, suggestion or motivation test should not be rigidly
`
`applied, but rather is an expansive and flexible test. For example, I have been
`
`informed that the common sense of a person of ordinary skill in the art can serve as
`
`motivation for combining references.
`
`35.
`
`I understand that the content of a patent or other printed publication (i.e., a
`
`reference) should be interpreted the way a person of ordinary skill in the art would
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`9
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`Pretech_000322
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`have interpreted the reference as of the effective filing date of the patent
`
`application for the ’370 Patent. I have assumed that the person of ordinary skill is a
`
`hypothetical person who is presumed to be aware of all the pertinent information
`
`that qualifies as prior art. In addition, the person of ordinary skill in the art makes
`
`inferences and creative steps. He or she is not an automaton, but has ordinary
`
`creativity.
`
`36.
`
`I have been informed that the application that issued as the ’370 Patent was
`
`filed in 2006. However, the application claims priority to a parent application that
`
`was filed on June 27, 1995. As a result, I will assume the relevant time period for
`
`determining what one of ordinary skill in the art knew is June 27, 1995, the
`
`effective filing date for purposes of this proceeding.
`
`D.
`
`Claim Construction
`
`37.
`
`I have been informed that a claim subject to inter partes review is given its
`
`“broadest reasonable construction in light of the specification of the patent in
`
`which it appears.” I have been informed that this means that the words of the
`
`claim are given their plain meaning from the perspective of one of ordinary skill in
`
`the art unless that meaning is inconsistent with the specification. I understand that
`
`the “plain meaning” of a term means the ordinary and customary meaning given to
`
`the term by those of ordinary skill in the art at the time of the invention and that the
`
`ordinary and customary meaning of a term may be evidenced by a variety of
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`10
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`sources, including the words of the claims, the specification, drawings, and prior
`
`art.
`
`38.
`
`I understand that in construing claims “[a]ll words in a claim must be
`
`considered in judging the patentability of that claim against the prior art.” (MPEP
`
`§ 2143.03, citing In re Wilson, 424 F.2d 1382, 1385 (CCPA 1970)).
`
`39.
`
`I understand that extrinsic evidence may be consulted for the meaning of a
`
`claim term as long as it
`
`is not used to contradict claim meaning that
`
`is
`
`unambiguous in light of the intrinsic evidence. Phillips v. AWH Corp., 415 F.3d
`
`1303, 1324 (Fed. Cir. 2005) (citing Vitronics Corp. v. Conceptronic, Inc., 90 F.3d
`
`1576, 1583-84 (Fed. Cir. 1996)). I also understand that in construing claim terms,
`
`the general meanings gleaned from reference sources must always be compared
`
`against the use of the terms in context, and the intrinsic record must always be
`
`consulted to identify which of the different possible dictionary meanings is most
`
`consistent with the use of the words by the inventor.
`
`See, e.g., Ferguson
`
`Beauregard/Logic Controls v. Mega Systems, 350 F.3d 1327, 1338 (Fed. Cir.
`
`2003) (citing Brookhill-Wilk 1, LLC v. Intuitive Surgical, Inc., 334 F.3d 1294, 1300
`
`(Fed. Cir. 2003)).
`
`III. TECHNOLOGY BACKGROUND
`
`A.
`
`Light Emitting Panel Assemblies
`
`40. By the time of the patent application to which the ‘370 patent claims priority
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`11
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`Pretech_000324
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`(early 1995),
`
`liquid crystal display (“LCD”)
`
`technology had progressed to
`
`commercial status and was used in products ranging from mobile phones and
`
`pagers to notebook computers and PC monitors. Small TVs based on LCD
`
`technology were also appearing in the market.
`
`41. An LCD is not a light emitting device, in contrast to plasma displays or
`
`CRTs used in many products. To create an image, the transmission of light
`
`through each picture element, or pixel, of the display is adjusted through an applied
`
`voltage to the LCD. In order to see an image, there are two modes of operation:
`
`reflective and transmissive. The majority of devices used in products are of the
`
`transmissive type and a source of light is needed to see an image. The backlight
`
`assembly of the ‘370 Patent is an example of a backlight that can be used in
`
`various products.
`
`42.
`
`The two types of backlights in use in the 1995 time frame are shown in the
`
`12
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`Pretech_000325
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`
`figure above. The upper portion of the diagram shows a “direct lit” backlight and
`
`the lower diagram shows an “edge-lit” backlight. The ‘370 patent describes
`
`various edge-lit assemblies. In the above illustration, the light sources are LEDs,
`
`which is common today. In the 1995 time frame, cold cathode fluorescent lamps
`
`(CCFL) were also commonly used in either type of backlight unit. To achieve a
`
`small overall thickness, thin CCFL lamps or small LED packages were typically
`
`used. Depending on the brightness requirements, two lamp assemblies were often
`
`used for edge-lit backlight assemblies, one on either end of the light guide panel.
`
`43.
`
`Prior to 1995, it was well-known that edge-lit backlight assemblies generally
`
`have three key parts:
`
`(1) the light source, (2) the light guide panel, and (3) the
`
`extraction and diffusion means so that the light in the light guide can exit towards
`
`the LCD with appropriate uniformity and directionality.
`
`44.
`
`The light source, e.g., a fluorescent lamp or an LED, was typically sized to
`
`match one edge of the light guide. For example, a 4mm thick light guide might
`
`utilize a 3mm diameter lamp or an LED with a 2-3 mm output. The light from a
`
`CCFL lamp is emitted isotropically, that is, equally in all directions; the light
`
`output distribution from an LED may be isotropic or can be slightly “focused” into
`
`a narrower light distribution. To improve efficiency of the backlight assembly,
`
`reflectors were typically added behind the light source, especially for CCFL lamps.
`
`The goal of the backlight designer in 1995 time frame (and today) was to capture
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`13
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`Pretech_000326
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`as much of the light from the source and “inject” it into the light guide panel.
`
`45.
`
`Light rays from a light source are often reflected or refracted at the input
`
`edge; the light entering a light guide from the source will travel different paths
`
`depending on the initial direction of the light and the physical size and shape of the
`
`light guide. Typically, and as will later be shown from the prior art to the ‘370
`
`Patent, light guides are thin transparent plates that extend in width and length much
`
`more than in height. For example, the height may be a few mm in extent to match
`
`the size of the light source and to achieve a thin backlight assembly, while the
`
`width and length match the size of the LCD, which are 10’s or 100’s of mm in
`
`extent for typical LCDs. As illustrated in the figure below, light rays from an LED
`
`travel through air in straight lines before hitting the input edge of the light guide.
`
`They are then are refracted at the air-light guide input edge boundary and are
`
`constrained by total internal reflection (“TIR”) to the height of the light guide or
`
`the width of the light guide.
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`14
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`Pretech_000327
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`46.
`
`
`
`
`
`The light guide panel uses the principle of totalThe light guide panel uses the principle of total internal reflection to “guide”internal reflection to “guide”
`
`
`
`
`
`light rays from the source to the extraction point. They always included a transitionlight rays from the source to the extraction point. They always included a transitionlight rays from the source to the extraction point. They always included a transition
`
`
`
`
`
`region between the edge of the light guide and the first extraction point so that lightregion between the edge of the light guide and the first extraction point so that lightregion between the edge of the light guide and the first extraction point so that light
`
`
`
`
`
`from the source could better “homogenize” before befrom the source could better “homogenize” before being extracted. The extractioning extracted. The extraction
`
`
`
`
`
`means were typically protrusions or depressions or painted scattering dots withmeans were typically protrusions or depressions or painted scattering dots withmeans were typically protrusions or depressions or painted scattering dots with
`
`
`
`
`
`variable density so as to extract light uniformly over the area of the light guidevariable density so as to extract light uniformly over the area of the light guidevariable density so as to extract light uniformly over the area of the light guide
`
`
`
`
`
`panel. Reflectors were usually added below the light guide papanel. Reflectors were usually added below the light guide panel and along thenel and along the
`
`
`rear and side -edges to improve efficiency.edges to improve efficiency.
`15
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`47. A typical extraction pattern for an edge lit backlight assembly is shown
`
`below. The referenced prior art patents in this Declaration show other examples.
`
`In this top view illustration, light from a light source enters the light guide panel
`
`and is extracted less (lower density of dots) near the light source where the light
`
`intensity is higher and is extracted more (higher density of dots) away from the
`
`light
`
`source
`
`where
`
`the
`
`light
`
`intensity
`
`is
`
`lower.
`
`48.
`
`The ’370 Patent discloses such a light emitting panel assembly, also called a
`
`light emitting assembly, which according to the ’370 Patent, is a device configured
`
`to produce a uniform illumination from a surface. This is a type of light box or
`
`luminaire, producing surface illumination. See, e.g., Ex. 1014, U.S. Patent No.
`
`5,160,195 (“Miller”). While these panel assemblies are used in many application
`
`contexts, e.g., architectural lighting, signage illumination, and x-ray film viewing,
`
`the primary application is in LCDs and the various applications thereof.
`
`In the
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`16
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`Pretech_000329
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`LCD context, a light emitting panel assembly is usually called the “backlight”
`
`module, which is important since it generates the light needed by the display, and
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`is primarily responsible for the brightness and power-efficiency of the whole
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`system. The other major module of an LCD is the “LC panel,” which is non-light
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`emitting and instead modulates light passing through it to form an image, where
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`each individual pixel acts as a shutter controlling how much light can pass through
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`it. See Ex. 1015, J. A. Castellano, Handbook of Display Technology, Academic
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`Press Inc., San Diego (1992), at pp. 9-13 and Ch. 8. A typical cross-section of a
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`light emitting panel assembly by the time of the ’370 Patent is illustrated in Fig. 2
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`from Ciupke, where the light emitting panel assembly includes everything below
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`element 12, and where element 12 is the LCD. Ex. 1005, U.S. Patent No.
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`5,461,547 (“Ciupke”), Fig. 2.
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`49.
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`The principle aim of a light emitting panel assembly is to provide a surface
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`of illumination that is as smooth as possible across its area, i.e., to emit light
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`uniformly from its entire spatial extent and into a desired angle distribution.
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`Unfortunately, there are no bright and efficient light sources that emit inherently
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`from a surface area commensurate with the size of an LCD, so point- and line-
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`shaped light sources are used instead. For example, light-emitting-diodes (LEDs)
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`have small emission areas typically on the order of a few mm2, and fluorescent
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`lamps, with either cold- (CCFL) or hot- (HCL) cathodes, can be many cm long but
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`only a few mm wide. The most critical engineering challenge for backlights,
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`therefore, is to produce the surface illumination with the target brightness and
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`uniformity at the lowest possible electrical power.
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`50.
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`As previously stated, light emitting panel assemblies are classified into two
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`well-known1 categories: “edge-lit” and “directly back-lit.” See, e.g., Fig. 9 from
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`Ex. 1016, U.S. Patent No. 5,598,280 (“Nishio”), versus Fig. 4 from Ex. 1017, U.S.
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`Patent No. 5,384,658 (“Ohtake”). These two categories are illustrated in Fig. A
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`below, with the light sources highlighted in each case. In the edge-lit category, the
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`light source is at
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`the edge, sending light substantially horizontally (in this
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`illustration), which must then be turned upward to emit upward (in this illustration)
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`through the emitting surface (and toward the display element in this illustration). In
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`the direct back-lit category, the light sources are arranged instead directly below
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`the emitting surface, usually with several films in between. Confusingly, the word
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`1 To be clear, when I refer to an element or concept as “well-known” or “known in
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`the prior art,” I particularly mean to say that the element or concept was well-
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`known as of June 27, 1995.
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`“backlight” is commonly applied to both. The ’370 Patent discloses an edge-lit
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`light emitting panel assembly. Edge-lit light emitting panel assemblies are often
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`preferred because they can be physically thinner and lower weight.
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`Figure A (Ex. 1016, annotated Fig. 9; Ex. 1017, Fig. 2)
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`51.
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`It was known by June 27, 1995 that one or more light sources may be
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`employed. As representative examples, see Ex. 1005, Fig. 4 below.
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`B.
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`Common Light Control Structures and Films
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`52. Many standard optical elements and surfaces within LCDs are used to
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`spatially homogenize and control the angular distribution of emitted light. These
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`include
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`light guides,
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`transition areas,
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`reflectors,
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`and various
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`types of
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`microstructured deformities (e.g., microprisms, diffusers, and microlenses). See,
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`e.g., Ex. 1018, U.S. Patent No. 5,303,322 (“Winston”). We now discuss each of
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`these.
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`53.
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`Light Guide. The light guide, also sometimes called a light pipe or wave
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`guide or optical conductor, accepts light injected from the side and distributes it
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`across the emission area. See, e.g., Ex. 1019, U.S. Patent No. 5,050,946
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`(“Hathaway”), Abstract and 1:56-59. The light guide is typically a transparent
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`planar slab that confines the light within it using the principle of total-internal-
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`reflection. Ex. 1019, 5:66-6:2. In some designs the light guide has parallel surfaces
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`and in other designs it has a wedge shape. Ex. 1019, Figs. 1 and 5.
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`54.
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`Light will generally only escape from the light guide into the emission
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`direction when disturbed by a structure – for example, a pattern of diffusing spots
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`on the back surface, or microstructures on one or both surfaces. Ex. 1019, 7:15-22.
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`For example, in the annotated Figure B of Ex. 1005, Ciupke below, the ray 24 is
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`shown first emitting from the light source 18, entering the light guide 11, bouncing
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`off the top and bottom surfaces of the light pipe several times, reflecting on the
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`right hand side by the edge reflector 29, hitting one of the groove 17 deformities,
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`and only then emitting from the light guide toward the LCD. Light guides were
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`generally known in the prior art.
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`It is important to note that the ’370 Patent
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`employs several terms for the light guide, including “transparent panel member”
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`(e.g., Ex. 1001, 1:20), “light emitting panel member” (, Ex. 1001, 1:20), “light emitting panel member” (e.g., Ex. 1001, 1:34, Ex. 1001, 1:34-35), and
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`
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`
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`“transparent light emitting panel” (“transparent light emitting panel” (e.g., Ex. 1001, 2:67).
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`Figure B (Ex. 1005, annotated Fig. 2)Figure B (Ex. 1005, annotated Fig. 2)
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`Transition Area. A transition area (or region) is commonly employed. A transition area (or region) is commonly employed. A transition area (or region) is commonly employed
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`55.
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`
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`
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`between the light source and the light guide, and is known in the art. Ex. 1001 atbetween the light source and the light guide, and is known in the art. Ex. 1001 atbetween the light source and the light guide, and is known in the art. Ex. 1001 at
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`
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`
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`2:58-3:3. This is a structure that usually has at least two functions: to securely3:3. This is a struc