UNITED STATES PATENT AND TRADEMARK OFFICE
`
`___________________
`
`BEFORE THE PATENT TRIAL AND APPEAL BOARD
`
`___________________
`
`
`
`
`
`
`
`
`
`DECLARATION OF BRIAN W. ANTHONY, PH.D.
`IN SUPPORT OF PETITION FOR INTER PARTES REVIEW OF
`U.S. PATENT 8,989,830
`
`
`
`
`
`i
`
`Apple Inc.
`APL1003
`U.S. Patent No. 8,989,830
`
`

`
`
`
`TABLE OF CONTENTS
`
`Introduction .................................................................................................... ..1
`
`State of the Art ............................................................................................. ..12
`
`II.
`
`III.
`
`IV.
`
`POW?‘
`
`TABLE OF CONTENTS
`Introduction ...................................................................................................... 1
`I.
`Qualifications ................................................................................................... 2
`II.
`Qualifications ................................................................................................. ..2
`III. My Understanding of Legal Principles ............................................................ 6
`My Understanding of Legal Principles .......................................................... ..6
`IV. Level of Ordinary Skill in the Art .................................................................11
`Level of Ordinary Skill in the Art ............................................................... ..11
`V.
`State of the Art ...............................................................................................12
`A. Non-invasive Optical Biosensors ..................................................................12
`Non-invasive Optical Biosensors ................................................................ ..12
`B. Photoplethysmography (PPG) .......................................................................15
`Photoplethysmography (PPG) ..................................................................... ..15
`C. Artifacts and Non-invasive Optical Biosensors ............................................17
`Artifacts and Non-invasive Optical Biosensors .......................................... ..17
`D. Progression from Wired to Wireless Devices ...............................................18
`Progression from Wired to Wireless Devices ............................................. ..18
`VI. The ’830 Patent ..............................................................................................19
`A. Overview of the ’830 Patent ..........................................................................19
`B. Summary of the Prosecution History ............................................................22
`Summary of the Prosecution History .......................................................... ..22
`VII. Claim Construction ........................................................................................23
`VIII. Overview of the Applied References ............................................................26
`Overview of the Applied References .......................................................... ..26
`A. Haahr ..............................................................................................................27
`B. Hicks ..............................................................................................................28
`C. Asada .............................................................................................................30
`D. Hannula ..........................................................................................................35
`IX. Overview of my Analysis ..............................................................................37
`Overview of my Analysis ............................................................................ ..37
`X. Ground 1: Haahr Renders Claims 1-4, 8-14, and 18-20 Obvious. ................38
`Ground 1: Haahr Renders Claims 1-4, 8-14, and 18-20 Obvious. .............. ..38
`A. Haahr renders independent claim 1 obvious. ................................................38
`Haahr renders independent claim 1 obvious. .............................................. ..38
`B. Haahr renders independent claim 11 obvious. ..............................................45
`Haahr renders independent claim 11 obvious. ............................................ ..45
`C. Haahr renders claims 2 and 12 obvious. ........................................................53
`D. Haahr renders claims 3 and 13 obvious. ........................................................54
`E. Haahr renders claims 4 and 14 obvious. ........................................................54
`F. Haahr renders claims 8 and 18 obvious. ........................................................56
`G. Haahr renders claims 9 and 19 obvious. ........................................................57
`H. Haahr renders claims 10 and 20 obvious. ......................................................58
`
`VI.
`
`The ’83O Patent ............................................................................................ ..19
`
`Overview of the ’83O Patent ........................................................................ ..19
`
`VII.
`
`Claim Construction ...................................................................................... ..23
`
`VIII.
`
`
`
`.><§FQTUFUUOWP“COP”?
`
`Haahr ............................................................................................................ ..27
`
`Hicks ............................................................................................................ ..28
`
`Asada ........................................................................................................... ..30
`
`Hannula ........................................................................................................ ..35
`
`Haahr renders claims 2 and 12 obvious ....................................................... ..53
`
`Haahr renders claims 3 and 13 obvious ....................................................... ..54
`
`Haahr renders claims 4 and 14 obvious ....................................................... ..54
`
`Haahr renders claims 8 and 18 obvious ....................................................... ..56
`
`Haahr renders claims 9 and 19 obvious ....................................................... ..57
`
`Haahr renders claims 10 and 20 obvious ..................................................... ..5 8
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`XI. Ground 2: The combination of Haahr and Hicks renders claims 5 and 15
`obvious. ..........................................................................................................60
`A. Motivation for the Combination of Haahr and Hicks ....................................60
`B. The combination of Haahr and Hicks discloses that “the light transmissive
`material comprises a lens region in optical communication with the at least
`one optical emitter that focuses light emitted by the at least one optical
`emitter.” .........................................................................................................61
`XII. Ground 3: The combination of Haahr, Asada, and Hannula renders claims 6
`and 16 obvious. ..............................................................................................62
`A. Motivation for the Combination of Haahr, Asada, and Hannula ..................62
`B. The combination of Haahr, Asada, and Hannula renders claims 6 and 16
`obvious. ..........................................................................................................65
`XIII. Conclusion .....................................................................................................72
`
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`I.
`
`Introduction
`
`I, Dr. Brian W. Anthony, declare as follows:
`
`1.
`
`
`I have been retained on behalf of Apple Inc. for the above-captioned
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`inter partes review proceeding to provide my expert opinions and expert
`
`knowledge. I understand that this proceeding involves U.S. Patent No. 8,989,830
`
`(“the ’830 patent”) titled “Wearable Light-Guiding Devices for Physiological
`
`Monitoring” by Steven F. LeBoeuf, Jesse B. Tucker, and Michael E. Aumer, and
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`that the ’830 patent is currently assigned to Valencell, Inc.
`
`2.
`
`
`In preparing this declaration, I have reviewed and am familiar with all
`
`the references cited herein. I have reviewed and am familiar with the ’830 patent
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`and its file history. I confirm that to the best of my knowledge the accompanying
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`exhibits are true and accurate copies of what they purport to be, and that an expert
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`in the field would reasonably rely on them to formulate opinions such as those set
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`forth in this declaration.
`
`3.
`
`
`The ’830 patent describes non-invasive optical biosensors for health
`
`monitoring. I am familiar with the technology described in the ’830 patent as of its
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`September 12, 2014 filing date and its claimed February 25, 2009 priority date.
`
`4.
`
`
`I have been asked to provide my independent technical review,
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`analysis, insights, and opinions regarding the ’830 patent and the references that
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`form the basis for the three grounds of rejection set forth in the Petition for Inter
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`Partes Review of the ’830 patent.
`
`5.
`
`
`I am being compensated at my rate of $350 per hour for my work on
`
`this case. My compensation is not dependent upon my opinions or testimony or the
`
`outcome of this case.
`
`II. Qualifications
`As indicated in my curriculum vitae (“CV”), included as Exhibit
`6.
`
`
`1004, I am currently a Principal Research Scientist at the Massachusetts Institute of
`
`Technology (“MIT”). My CV
`
`includes additional
`
`information about my
`
`professional history and contains further details on my experience, publications,
`
`patents, and other qualifications to render an expert opinion. Herein, I highlight
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`experiences relevant to the technology of the patent at issue.
`
`7.
`
`
`I earned a Bachelor of Science in Engineering from Carnegie Mellon
`
`University in 1994 and a Master’s degree in Engineering from MIT in 1998. My
`
`thesis topic related to anisotropic wave guides and acoustic non-destructive testing.
`
`In 2006, I earned my Ph.D. in Engineering from MIT. My research focused on
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`high-performance computation, signal processing, and electro-mechanical system
`
`design.
`
`8.
`
`
`In 1997, I co-founded Xcitex Inc., a company that specialized in
`
`video-acquisition and motion-analysis software. I served as the Chief Technology
`
`Officer and directed and managed product development until 2006. Our first demo-
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`product was an optical ring for human motion measurement used to capture user
`
`hand motion in order to control the user’s interaction with a computer. Many of the
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`structural elements of our optical ring – developed more than a decade prior to the
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`’830 patent’s earliest possible priority date – addressed the same system issues as
`
`those described and claimed in the ’830 patent. For example, our optical ring
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`included optical structures for light blocking, light redirection, and light capture.
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`We estimated human hand-motion based on how that motion changed the detected
`
`light. In our application we did not try to eliminate motion artifact, we tried to
`
`measure it. In developing our ring, we considered well-known problems such as
`
`extraneous light and motion, which are, unsurprisingly, also discussed in the ’830
`
`patent.
`
`9.
`
`
`I joined MIT in 2006 and have been the Director of the Master of
`
`Engineering in Advance Manufacturing and Design Program for over ten years.
`
`The degree program covers four main components–Manufacturing Physics,
`
`Manufacturing Systems, Product Design, and Business Fundamentals. Many of the
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`courses, projects, and papers my students undertake involve technologies relevant
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`to the ’830 patent, for example, sensor devices including non-invasive optical
`
`biosensors.
`
`10.
`
`
`In 2011, I co-founded MIT’s Medical Electronic Device Realization
`
`Center (“MEDRC”) and currently serve as co-director. The MEDRC aims to create
`
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`and deploy revolutionary medical technologies by collaborating with clinicians, the
`
`microelectronics, and medical devices industries. We combine expertise in
`
`computation; communications; optical, electrical, and ultrasound sensing
`
`technologies; and consumer electronics. We focus on the usability and productivity
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`of medical devices using, for example, image and signal processing combined with
`
`intelligent computer systems to enhance practitioners’ diagnostic intuition. Our
`
`research portfolio includes low power integrated circuits and systems, big data,
`
`micro electro-mechanical systems, bioelectronics, sensors, and microfluidics.
`
`Specific areas of innovation include wearable, non-invasive and minimally
`
`invasive optical biosensor devices, medical imaging, laboratory instrumentation,
`
`and the data communication from these devices and instruments to healthcare
`
`providers and caregivers. My experience with these devices is directly applicable
`
`to the technology in the ’830 patent. For example, one current project related to
`
`this work is in laser-ultrasound tomography. In this work, an eye and skin safe-
`
`pulsed laser beam is directed at the body and reflected and transmitted signals are
`
`used to map internal tissue structures. In another current project, we use a patient-
`
`mounted mobile near infrared (NIR) camera to image and characterize the surface
`
`and subsurface structures of the skin.
`
`
`
` Furthermore, my research focuses on computational instrumentation, 11.
`
`including the development of instrumentation and measurement solutions for
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`manufacturing systems and medical devices. Additionally, my teaching interests
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`include the design and modeling of large-scale systems in a wide variety of
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`decision-making domains and developing optimization algorithms and software for
`
`analyzing and designing such systems. I teach or have taught courses in Electrical
`
`Engineering, Controls, Optics, and Signal Processing, all pertinent subject matter
`
`to the ’830 patent.
`
`12.
`
`
`I also co-founded the Center for Polymer Micro-fabrication at MIT.
`
`The Center’s research focuses on polymer-based manufacturing processes and the
`
`large-scale commercialization of micro fluidic devices for chemical, biomedical,
`
`and photonic applications. My experience under these initiatives is directly
`
`applicable to the technology in the ’830 patent. We develop optical sensors to non-
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`invasively monitor soft flexible materials during the manufacturing process.
`
`13.
`
`
`I have published approximately 50 papers, and have received a
`
`number of best paper and distinguished paper awards. I am a co-author of a
`
`number of papers that relate to the technology in the ’830 patent, such as:
`
`• Ranger, Bryan J.; Feigin, Micha; Pestrov, Nikita; Zhang, Xiang;
`
`Lempitsky, Victor; Herr, Hugh M.; Anthony, Brian W., “Motion
`
`compensation in a tomographic ultrasound imaging system:
`
`Toward volumetric scans of a limb for prosthetic socket design,”
`
`2015 37th Annual International Conference of
`
`the IEEE
`
`
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`- 5 -
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`Engineering in Medicine and Biology Society (EMBC), pp. 7204-
`
`7207;
`
`• Shih-Yu Sun, Matthew Gilbertson, and Brian W. Anthony, “Probe
`
`Localization for Freehand 3D Ultrasound by Tracking Skin
`
`Features,” Book Section, Medical
`
`Image Computing and
`
`Computer-Assisted Intervention, MICCAI 2014, Springer, 2014,
`
`Vol. 8674, Lecture Notes in Computer Science, pp. 365-372;
`
`• J. H. Lee, C. M. Schoellhammer, G. Traverso, D. Blankschtein, R.
`
`Langer, K. E. Thomenius, D. S. Boning, B. W. Anthony, “Towards
`
`Wireless Capsule Endoscopic Ultrasound
`
`(WCEU),”
`
`IEEE
`
`International Ultrasonics Symposium (IUS), Chicago, IL, 2014, pp.
`
`734-737; and
`
`• Zakrzewski, A., Anthony, B. W., “Quantitative Elastography and
`
`its Application to Blood Pressure Estimation: Theoretical and
`
`Experimental Results,” 2013 IEEE Engineering in Medicine and
`
`Biology Society (EMBC), pp. 1136-1139.
`
`III. My Understanding of Legal Principles
`I understand that my analysis requires an understanding of the scope
`14.
`
`
`of the ’830 patent claims and that the disclosures of the ’830 patent and the prior
`
`art are judged from the perspective of a person of ordinary skill in the art at the
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`time of the purported invention. For the purposes of this declaration, I have been
`
`instructed to consider the time of the purported invention of the ’830 patent to be
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`February 25, 2009, the earliest possible priority date for the ’830 patent. I note,
`
`however, that my opinions would not change even if all the relevant disclosures
`
`were judged from a later time period.
`
`15.
`
`
`I understand that during an inter partes review, claims of an unexpired
`
`patent are to be given their broadest reasonable construction in light of the
`
`specification as would be understood by a person of ordinary skill in the relevant
`
`art. Unless otherwise noted, I have given the claim terms their plain and ordinary
`
`meaning as understood by a person of ordinary skill in the art at the time of
`
`purported invention.
`
`16.
`
`
`I understand that a claim is invalid if it is anticipated or obvious. I
`
`understand that anticipation of a claim requires that every element of a claim is
`
`expressly or inherently disclosed in a single prior art reference. I understand that an
`
`anticipating reference need not use the exact terms of the claims, but must describe
`
`the patented subject matter with sufficient clarity and detail to establish that the
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`claimed subject matter existed in the prior art and that such existence would be
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`recognized by persons of ordinary skill in the field of the purported invention. I
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`also understand that an anticipating reference must enable one of ordinary skill in
`
`the art
`
`to
`
`reduce
`
`the purported
`
`invention
`
`to practice without undue
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`experimentation.
`
`17.
`
`
`I understand that a patent claim is invalid if the claimed invention
`
`would have been obvious to a person of ordinary skill in the art at the time of the
`
`purported invention. This means that even if all of the requirements of the claim
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`cannot be found in a single prior art reference that would anticipate the claim, the
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`claim can still be invalid.
`
`18.
`
`
`I understand that an obviousness analysis involves comparing a claim
`
`to the prior art to determine whether the claimed invention would have been
`
`obvious to a person of ordinary skill in the art at the time of the purported
`
`invention in view of the prior art and in light of the general knowledge in the art as
`
`a whole. I also understand that obviousness is ultimately a legal conclusion based
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`on underlying facts of four general types, all of which must be considered: (1) the
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`scope and content of the prior art; (2) the level of ordinary skill in the art; (3) the
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`differences between the claimed invention and the prior art; and (4) any objective
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`indicia of nonobviousness.
`
`19.
`
`
`I also understand that obviousness may be established by combining
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`or modifying the teachings of the prior art. Specific teachings, suggestions, or
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`motivations to combine any first prior art reference with a second prior art
`
`reference can be explicit or implicit, but must have existed before the date of
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`purported invention. I understand that prior art references themselves may be one
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`source of a specific teaching or suggestion to combine features of the prior art, but
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`that such suggestions or motivations to combine art may come from the knowledge
`
`of a person of ordinary skill in the art. Specifically, a rationale to combine the
`
`teachings of references may include logic or common sense available to a person
`
`of ordinary skill in the art.
`
`20.
`
`
`I understand that a reference may be relied upon for all that it teaches,
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`including uses beyond its primary purpose. I understand that though a reference
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`may be said to teach away when a person of ordinary skill, upon reading the
`
`reference, would be discouraged from following the path set out in the reference,
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`the mere disclosure of alternative designs does not teach away.
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`21.
`
`
`I further understand that whether there is a reasonable expectation of
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`success from combining references in a particular way is also relevant to the
`
`analysis. I understand there may be a number of rationales that may support a
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`conclusion of obviousness, including:
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`• Combining prior art elements according to known methods to yield
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`predictable results;
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`• Substitution of one known element for another to obtain predictable
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`results;
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`• Use of a known technique to improve similar devices (methods, or
`
`products) in the same way;
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`- 9 -
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`• Applying a known technique to a known device (method, or product)
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`ready for improvement to yield predictable results;
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`• “Obvious to try” – choosing from a finite number of identified,
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`predictable solutions, with a reasonable expectation of success;
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`• Known work in one field of endeavor may prompt variations of it for use
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`in either the same field or a different one based on design incentives or
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`other market forces if the variations are predictable to one of ordinary
`
`skill in the art; and
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`• Some teaching, suggestion, or motivation in the prior art that would have
`
`led one of ordinary skill to modify the prior art reference or to combine
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`prior art teachings to arrive at the claimed invention.
`
`22.
`
`
`I understand that it is not proper to use hindsight to combine
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`references or elements of references to reconstruct the invention using the claims
`
`as a guide. My analysis of the prior art is made from the perspective of a person of
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`ordinary skill in the art at the time of the purported invention.
`
`23.
`
`
`I understand that so-called objective considerations may be relevant to
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`the determination of whether a claim is obvious should the Patent Owner allege
`
`such evidence. Such objective considerations can include evidence of commercial
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`success caused by an invention, evidence of a long-felt need that was solved by an
`
`invention, evidence that others copied an invention, or evidence that an invention
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`achieved a surprising result. I understand that such evidence must have a nexus, or
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`causal relationship to the elements of a claim, in order to be relevant to the
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`obviousness or non-obviousness of the claim. I am unaware of any such objective
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`considerations having a nexus to the claims at issue in this proceeding.
`
`24.
`
`
`I understand that for a reference to be used to show that a claim is
`
`obvious, the reference must be analogous art to the claimed invention. I understand
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`that a reference is analogous to the claimed invention if the reference is from the
`
`same field of endeavor as the claimed invention, even if it addresses a different
`
`problem, or if the reference is reasonably pertinent to the problem faced by the
`
`inventor, even if it is not in the same field of endeavor as the claimed invention. I
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`understand that a reference is reasonably pertinent based on the problem faced by
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`the inventor as reflected in the specification, either explicitly or implicitly.
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`IV. Level of Ordinary Skill in the Art
`I understand that the person of ordinary skill in the art (“POSA”) is
`25.
`
`
`viewed at the time of invention. For the purpose of this declaration, I have
`
`evaluated the level of ordinary skill in the art as of February 25, 2009, the earliest
`
`possible priority date for the ’830 patent. Based on the disclosure of the ’830
`
`patent, it is my opinion that a POSA at the relevant time would have had at least a
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`four-year degree in electrical engineering, mechanical engineering, biomedical
`
`engineering, optical engineering, or related field of study, or equivalent experience,
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`and at least two years’ experience in academia or industry studying or developing
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`physiological monitoring devices such as non-invasive optical biosensors. A
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`person of ordinary skill in the art would have also been familiar with, for example,
`
`optical system design and signal processing. This description is approximate, and a
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`higher level of education or skill might make up for less experience, and vice-
`
`versa.
`
`
`
` Based on my knowledge, skill, and experience, I have an 26.
`
`understanding of the capabilities of a person of ordinary skill in the relevant art.
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`For example, from my industry experience, I am familiar with what an engineer
`
`designing non-invasive optical biosensors would have known and found
`
`predictable in the art. From teaching and supervising my post-graduate students, I
`
`also have an understanding of the knowledge that a person with this academic
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`experience possesses. Furthermore, I possessed those capabilities myself at least as
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`of February 25, 2009.
`
`V.
`
`State of the Art
`A. Non-invasive Optical Biosensors
` The ’830 patent and the prior art references discussed herein are all 27.
`
`
`from the field of non-invasive optical biosensors. These devices have a wide range
`
`of applications, for example, measuring blood flow characteristics such as blood
`
`oxygen saturation, blood pressure, and cardiac output. Non-invasive optical
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`biosensors are generally characterized as devices that pass light from a light source
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`through the skin (i.e., non-invasive) into a blood perfused area of body tissue and
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`then use a photodetector to sense the absorption of light in the tissue. (APL1001,
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`3:67-4:5; APL1005, p. 28; APL1006, 1:11-17; APL1007, 1:20-40; APL1008, 1:10-
`
`25; APL1009, 1:9-27; APL1010, 1:9-20; APL1011, ¶4.)
`
`
`
` Non-invasive optical biosensors can take various form-factors, for 28.
`
`example, flat sensors, wraps, clamps, or rings. (APL1005, p. 34; APL1006, 5:14-
`
`23; APL1007, 4:30-37; APL1011, ¶34; APL1013, p. 8; APL1014, p. 407;
`
`APL1015, p. 913; APL1016, 3:42-46, Figures 1A-1B, 24.) One common and well-
`
`understood non-invasive optical biosensor is a pulse oximeter, which is described
`
`in an embodiment of the ’830 patent. (See e.g., APL1001, 23:1-26.) Pulse
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`oximeters have been known since at least the 1970’s, with technology used in
`
`pulse oximeters dating back to the 1930’s. (APL1017, p. 98.) Pulse oximetry is a
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`widely used method for monitoring arterial hemoglobin oxygen saturation (SpO2).
`
`(APL1005, p. 30; APL1006, 1:11-17; APL1007, 1:34-40; APL1017, p. 98.)
`
`
`
` The system components of non-invasive optical biosensors, like pulse 29.
`
`oximeters, have been rather customary for decades. Typical components include:
`
`one or more electrically controlled optical light-sources; mechanical and optical
`
`elements to guide and focus the light into the body; mechanical and optical
`
`elements to control light within the sensing device; mechanical and optical
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`elements to capture and focus the light leaving the body; light detector(s) that
`
`generate an electrical signal proportional to the intensity of received light;
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`processor(s) to control the light source; and processor(s) to analyze the electrical
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`signals. For example, a pulse oximeter described by Mendelson in 1991, shown
`
`below, included multiple LEDs, multiple photodiodes, an optical shield, and an
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`optically clear epoxy, mounted on a silicon rubber base. (APL1013, p. 8, Figure 1.)
`
`
`
` Other well-known components 30.
`
`
`include optical or mechanical
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`components to block or capture-and-divert stray internal and ambient light;
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`mechanical elements to firmly and comfortably affix the device to a selected
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`location on the body; and sub-systems (e.g., sensors and algorithms) to measure
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`and compensate for motion. (APL1005, pp. 31-33 (motion/noise algorithms);
`
`APL1006, 5:28-31 (sensor adhesively fastened to skin); APL1009, 2:58-66, 4:46-
`
`54 (reflective and opaque materials to redirect and block light).)
`
` Another example, U.S. Patent No. 5,226,417 to Swedlow et al., filed
`31.
`
`in 1991, describes a layered non-invasive optical biosensor that is wrapped around
`
`a finger. Swedlow discloses a number of typical components found in non-invasive
`
`optical biosensors, including: an outer layer or covering (bandage layer 21); optical
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`emitters (LEDs 13, 16); an optical detector (photodetector 15); a light transmissive
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`layer protecting the optical components (clear polyethylene layer 12); and a light-
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`blocking or “cladding” layer (opaque white polypropylene layer 14) with holes for
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`the optical components. (APL1006, 5:42-51, 5:66-68, Figure 2.)
`
`
`
`B. Photoplethysmography (PPG)
`
`
`
` Photoplethysmography (PPG) is an optical technique used by many 32.
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`non-invasive optical biosensors, like pulse oximeters, to detect blood flow
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`characteristics such as blood volume changes in a microvascular bed of tissue. (See
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`e.g., APL1013, p. 7.) The technique relies on a PPG sensor to detect a PPG signal
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`produced by variations in the quantity of arterial blood associated with periodic
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`cardiac contraction and relaxation. (Id. at 8.) The PPG signal has pulsatile (AC)
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`components attributed to changes in the blood volume synchronous with each
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`heartbeat and is superimposed on a low frequency (DC) baseline with variation
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`from respiration, sympathetic nervous system activity, and thermoregulation.
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`(APL1017, p. 101.) The ’830 patent repeatedly highlights the use of PPG in
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`embodiments of the disclosed sensor devices. (APL1001, 3:67-4:5, 11:38-40,
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`13:35-38, 20:50-57, 21:14-25, 23:7-10, 26:25-34.)
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` Using PPG, blood flow characteristics like SpO2 values can be 33.
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`derived from an empirically calibrated function. For example, the time-varying
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`(AC) signal component of the PPG at each wavelength can be divided by the
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`corresponding time-invariant (DC) component which is due to light absorption and
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`scattering by bloodless tissue, residual arterial blood volume during diastole, and
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`non-pulsatile venous blood. (APL1017, p. 101.)
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` PPG measurements can be performed in either transmission (also 34.
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`called transmittal or transmittance) or reflection modes. (APL1013, pp. 7-8;
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`APL1014, p. 405; APL1015, p. 912.) A POSA would have been familiar with both
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`of these modes and understood that components of devices used primarily for one
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`mode could be adapted for use with the other mode. (APL1013, p. 8; APL1010,
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`3:53-58.) In transmission mode, the sensor is usually attached across a body part,
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`for example, a fingertip or earlobe, so that the LED(s) and photodetector are placed
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`on opposite sides of a pulsating vascular bed. (APL1014, pp. 403, 405; APL1015,
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`p. 912.) In transmission mode, light emitted from the LED(s) is diffused by the
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`skin and subcutaneous tissues predominantly in a forward-scattering direction. In
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`reflection mode, the LED(s) and photodetector are both mounted facing the same
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`side of the vascular bed. (APL1013, p. 8; APL1014, p. 405; APL1015, p. 912.) In
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`reflection mode, only a small fraction of the incident light is backscattered by the
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`subcutaneous layers. (APL1015, p. 914.) The backscattered light intensity reaching
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`the skin surface is typically distributed over a relatively large area surrounding the
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`LEDs. (Id.) Hence, the design of a reflectance-mode often includes a sensor that
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`has improved sensitivity to detect sufficiently strong PPG signals from the body
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`combined with sophisticated digital signal processing algorithms to process the
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`relatively weak and often noisy signals. (APL1013, p. 8.)
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`C. Artifacts and Non-invasive Optical Biosensors
` Sources of error and artifacts for non-invasive optical biosensors, for 35.
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`example, associated with the PPG technique, have been known since the technique
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`was first used. Artifact has three major sources: ambient light, low perfusion, and
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`motion, which all lead to poor signal-to-noise ratio. (APL1017, p. 103; APL1013,
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`p. 8; APL1014, p. 405; APL1005, p. 30; APL1006, 1:5-10, 3:6-16; APL1007,
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`3:56-62; APL1008, 2:42-45.) It has been long recognized that noise sources such
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`as stray and ambient light and movement of the subject corrupt the information that
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`is obtained from non-invasive optical biosensors. Motion artifacts arise from
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`kinematic or mechanical forces, changes in the coupling of the sensor to the
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`subject, local variation in patient anatomy, optical properties of tissue due to
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`geometric realignment or compression, or combinations of these effects.
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` Multiple ways to compensate for these artifacts were well understood 36.
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`before 2009. Examples include:
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`• mechanical elements–for example, adhesives
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`to reduce sensor
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`movement (APL1006, 5:28-36; APL1007, 4:59-5:2);
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`• optical elements–for example, shielding materials (APL1013, p. 8;
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`APL1014, pp. 406-407; APL1005, pp. 34-35; APL1007, 9:11-16);
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