`571-272-7822
`
`Paper 31
`Entered: April 12, 2022
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`UNITED STATES PATENT AND TRADEMARK OFFICE
`
`BEFORE THE PATENT TRIAL AND APPEAL BOARD
`
`APPLE INC.,
`Petitioner,
`v.
`MASIMO CORPORATION,
`Patent Owner.
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`IPR2020-01526
`Patent 6,771,994 B2
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`Before JOSIAH C. COCKS, ROBERT L. KINDER, and
`AMANDA F. WIEKER, Administrative Patent Judges.
`KINDER, Administrative Patent Judge.
`
`
`
`JUDGMENT
`Final Written Decision
`Determining the Challenged Claim Unpatentable
`35 U.S.C. § 318(a)
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`I.
`
`INTRODUCTION
`
`Background
`A.
`Apple Inc. (“Petitioner”) filed a Petition requesting an inter partes
`review of claim 15 of U.S. Patent No. 6,771,994 B2 (Ex. 1001, “the ’994
`patent”). Paper 2 (“Pet.”). Masimo Corporation (“Patent Owner”) waived
`filing a Preliminary Response. Paper 6. We instituted an inter partes review
`of the challenged claim on all asserted grounds of unpatentability, pursuant
`to 35 U.S.C. § 314. Paper 7 (“Institution Decision” or “Inst. Dec.”).
`After institution, Patent Owner filed a Response (Paper 12, “PO
`Resp.”) to the Petition, Petitioner filed a Reply (Paper 17, “Pet. Reply”), and
`Patent Owner filed a Sur-reply (Paper 19, “Sur-reply”). An oral hearing was
`held on January 19, 2022, and a transcript of the hearing is included in the
`record. Paper 30 (“Tr.”).
`We issue this Final Written Decision pursuant to 35 U.S.C. § 318(a)
`and 37 C.F.R. § 42.73. Based on the record before us and for the reasons set
`forth below, Petitioner has met its burden of showing, by a preponderance of
`the evidence, that claim 15 of the ’994 patent is unpatentable.
`
`Related Matters
`B.
`The parties identify the following matters related to the ’994 patent:
`Masimo Corporation v. Apple Inc., Civil Action No. 8:20-cv-00048
`(C.D. Cal.) (filed Jan. 9, 2020);
`Apple Inc. v. Masimo Corporation, IPR2020-01520 (PTAB
`Aug. 31, 2020) (challenging claims of U.S. Patent No. 10,258,265 B1);
`Apple Inc. v. Masimo Corporation, IPR2020-01521 (PTAB
`Sept. 2, 2020) (challenging claims of U.S. Patent No. 10,292,628 B1);
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`Apple Inc. v. Masimo Corporation, IPR2020-01523 (PTAB
`Sept. 9, 2020) (challenging claims of U.S. Patent No. 8,457,703 B2);
`Apple Inc. v. Masimo Corporation, IPR2020-01524 (PTAB
`Aug. 31, 2020) (challenging claims of U.S. Patent No. 10,433,776 B2);
`Apple Inc. v. Masimo Corporation, IPR2020-01536 (PTAB
`Aug. 31, 2020) (challenging claims of U.S. Patent No. 10,588,553 B2);
`Apple Inc. v. Masimo Corporation, IPR2020-01537 (PTAB
`Aug. 31, 2020) (challenging claims of U.S. Patent No. 10,588,553 B2);
`Apple Inc. v. Masimo Corporation, IPR2020-01538 (PTAB
`Sept. 2, 2020) (challenging claims of U.S. Patent No. 10,588,554 B2); and
`Apple Inc. v. Masimo Corporation, IPR2020-01539 (PTAB
`Sept. 2, 2020) (challenging claims of U.S. Patent No. 10,588,554 B2).
`Pet. 68; Paper 3, 2.
`
`The parties further identify certain pending patent applications, as
`well as other issued applications, that claim priority to, or share a priority
`claim with, the ’994 patent. Paper 3, 1.
`
`The ’994 Patent
`C.
`The ’994 patent is titled “Pulse Oximeter Probe-Off Detection
`System,” and issued on August 3, 2004, from U.S. Patent Application
`No. 10/374,303, filed February 24, 2003. Ex. 1001, codes (21), (22), (45),
`(54). The ’994 patent claims priority through a series of applications to
`Provisional Application No. 60/140,000, filed June 18, 1999. Id. at
`codes (60), (62).
`The ’994 patent relates to a pulse oximeter probe that detects when a
`probe has become dislodged from a patient or that acts to prevent a potential
`probe-off condition. Ex. 1001, code (57). The ’994 patent relies on
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`electrical contacts that contact the skin of a patient when the probe is
`properly attached and a number of louvers placed in front of a sensor’s
`photodetector to filter out oblique light rays that do not originate from a
`point in front of the detector. Id. According to one aspect of the invention,
`if the emitter and photodetector are not properly aligned, the photodetector
`will not produce a signal within the valid operating range of the pulse
`oximeter, which may trigger an alarm or warning. Id.
`As depicted in Figure 1 below, pulse oximeter 140 is attached through
`connector 142 to probe 110 and probe 110 comprises LEDs 112, 114, which
`are “preferably configured to produce different wavelengths of light.” Id. at
`3:21–55, Fig. 1.
`
`
`Figure 1 illustrates a schematic of a pulse oximeter system. Id. at 2:30–31.
`The wavelengths of light pass through the flesh of a patient to be detected by
`photodetector 116. Id. at 3:34–37, Fig. 1. The ’994 patent describes certain
`embodiments where the photodetector is placed opposite the light emitters to
`detect transmitted light as it emerges from the user’s body tissue. See id. at
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`1:41–43 (describing the configuration of known pulse oximetry probes as
`positioning the detector “opposite the LED”), 4:19–25 (“the emitters located
`within the probe are spaced opposite the detector assembly 235 . . . such that
`the light from the emitters passes . . . through the finger 250 and is incident
`upon the detector assembly 235”), Figs. 2A–B, 4, 5A–B.
`As illustrated in Figure 5B below, if probe 202 is properly attached
`emitter aperture 220 will be directly in front of detector assembly 235 and
`light rays will pass directly through louvers 502 along direct path 510. Id. at
`6:29–33.
`
`
`Figure 5B illustrates a properly attached probe wherein a number of
`louvers (502) are placed in front of the detector assembly. Ex. 1001, 2:60–
`62.
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`D. Claim 15
`Claim 15 is the only challenged claim and it is reproduced below.
`15. [pre] A sensor which generates at least first and second
`intensity signals from a light-sensitive detector which detects
`light of at least first and second wavelengths transmitted through
`body tissue carrying pulsing blood; the sensor comprising:
`[a] at least one light emission device;
`[b] a light sensitive detector; and
`[c] a plurality of louvers positioned over the light sensitive
`detector to accept light from the at least one light emission device
`originating from a general direction of the at least one light
`emission device and then transmitting through body tissue
`carrying pulsing blood, wherein the louvers accept the light when
`the sensor is properly applied to tissue of a patient.
`Ex. 1001, 8:21–35 (bracketed identifiers pre–c added).
`
`Applied References
`E.
`Petitioner relies upon the following references:
`Diab et al., U.S. Patent No. 5,638,818, filed November 1, 1994,
`issued June 17, 1997 (Ex. 1006, “Diab”);
`Benjamin et al., U.S. Patent No. 4,015,595, filed
`September 15, 1975, issued April 5, 1977 (Ex. 1007, “Benjamin”);
`Melby et al., U.S. Patent No. 5,254,388, filed December 20,
`1991, issued October 19, 1993 (Ex. 1008, “Melby”);
`Fine, WO Pub. No. 1996/41566, filed June 6, 1995, published
`December 27, 1996 (Ex. 1009, “Fine”); and,
`Webster, Excerpts from Design of Pulse Oximeters, J.G.
`Webster; Institution of Physics Publishing, 1997 (Ex. 1010,
`“Webster”).
`Pet. 3–4.
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`Petitioner also submits, inter alia, the Declaration of Brian W.
`Anthony, Ph.D. (Ex. 1003). Patent Owner submits, inter alia, the
`Declaration of Vijay K. Madisetti, Ph.D. (Ex. 2001). The parties also
`provide deposition testimony from Dr. Anthony and Dr. Madisetti.
`Exs. 1038, 2003.
`
`Asserted Grounds
`F.
`We instituted an inter partes review based on the following grounds.
`Inst. Dec. 7, 29.
`Claim Challenged
`15
`15
`15
`15
`
`Reference(s)/Basis
`Diab, Benjamin, Melby
`Webster, Melby
`Fine
`Fine, Benjamin, Melby
`
`35 U.S.C. §
`103
`103
`103
`103
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`II. DISCUSSION
`Claim Construction
`A.
`For petitions filed on or after November 13, 2018, a claim shall be
`construed using the same claim construction standard that would be used to
`construe the claim in a civil action under 35 U.S.C. § 282(b), including
`construing the claim in accordance with the ordinary and customary
`meaning of such claim as understood by one of ordinary skill in the art and
`the prosecution history pertaining to the patent. 37 C.F.R. § 42.100(b)
`(2019).
`Petitioner submits that the entirety of clause 15[c] requires
`construction. Pet. 8. Clause 15[c] (set forth above), requires in part, “a
`plurality of louvers positioned over the light sensitive detector to accept light
`from the at least one light emission device originating from a general
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`direction of the at least one light emission device and then transmitting
`through body tissue.” Ex. 1001, 8:29–35 (emphases added). Petitioner
`contends that this limitation requires that the light sensitive detector must
`“be positioned opposite the at least one light emission device.” Pet. 8–9.
`Petitioner seemingly bases this interpretation on one embodiment in the
`Specification, “which only depict[s] and describe[s] the placement of the
`body tissue carrying pulsing blood between the at least one light emission
`device and the light sensitive detector.” Pet. 9 (citing Ex. 1001, 1:41–43
`(“[T]he ‘photodiode is positioned opposite the LED so as to detect the LED
`transmitted light as it emerges from the [body] tissue.’” (second alteration in
`original))).
`Although Petitioner describes one embodiment of the invention that
`may be encompassed by the claim scope, this one embodiment is narrower
`in scope than the claim language of clause 15[c]. For example, the claim
`requires the louvers positioned over the detector to accept light originating
`from a general direction of the at least one light emission device, while the
`light also passes through tissue. Petitioner contends that for this to occur the
`detector must be positioned opposite the light emission device, as depicted
`in Figure 5B. Pet. 9.
`In the Institution Decision, we noted that Petitioner does not explain
`why it is even necessary to adopt its proposed claim construction. Inst.
`Dec. 8–9. We noted that for purposes of our analysis, we accept that the
`embodiment Petitioner relies upon (positioned opposite) is within the claim
`scope of clause 15[c], but we were not prepared to limit the claim to just this
`embodiment without further explanation and evidence. Id. We determined
`that clause 15[c] provides sufficient detail as to the positioning of elements
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`such that further defining the limitation did not seem necessary. We invited
`the parties to further explain why these terms would require construction for
`this proceeding. Id. at 9.
`In its Response, Patent Owner argued that further defining the
`limitations of clause 15[c] is not necessary. PO Resp. 22. Patent Owner
`contends that “Apple’s attempt to inject the non-claimed requirement of the
`detector being opposite the light emission device is unnecessary and
`inappropriate.” Id. Patent Owner provides several reasons in support of this
`position. Id. at 22–26. Likewise, at oral argument Patent Owner maintained
`it was unnecessary to reach the claim construction issue in this proceeding.
`See Tr. 38:3–19.
`In its Reply, Petitioner did not provide any justification as to why it
`would be necessary in this proceeding to construe the limitations of clause
`15[c]. See generally Pet. Reply.
`Based on the final record, it is unnecessary for us to construe the
`limitations of clause 15[c] as requested by Petitioner. We determine that
`clause 15[c] provides sufficient detail as to the positioning of elements such
`that further defining the limitation is not necessary to resolve this
`proceeding. Further, no other terms require construction.
`
`Principles of Law
`B.
`A claim is unpatentable under 35 U.S.C. § 103 if “the differences
`between the subject matter sought to be patented and the prior art are such
`that the 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 to which said
`subject matter pertains.” KSR Int’l Co. v. Teleflex Inc., 550 U.S. 398, 406
`(2007). The question of obviousness is resolved on the basis of underlying
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`factual determinations, including (1) the scope and content of the prior art;
`(2) any differences between the claimed subject matter and the prior art;
`(3) the level of skill in the art; and (4) objective evidence of non-
`obviousness.1 Graham v. John Deere Co., 383 U.S. 1, 17–18 (1966). When
`evaluating a combination of teachings, we must also “determine whether
`there was an apparent reason to combine the known elements in the fashion
`claimed by the patent at issue.” KSR, 550 U.S. at 418 (citing In re Kahn,
`441 F.3d 977, 988 (Fed. Cir. 2006)). Whether a combination of prior art
`elements would have produced a predictable result weighs in the ultimate
`determination of obviousness. Id. at 416–417.
`In an inter partes review, the petitioner must show with particularity
`why each challenged claim is unpatentable. Harmonic Inc. v. Avid Tech.,
`Inc., 815 F.3d 1356, 1363 (Fed. Cir. 2016); 37 C.F.R. § 42.104(b). The
`burden of persuasion never shifts to Patent Owner. Dynamic Drinkware,
`LLC v. Nat’l Graphics, Inc., 800 F.3d 1375, 1378 (Fed. Cir. 2015).
`We analyze the challenges presented in the Petition in accordance
`with the above-stated principles.
`
`Level of Ordinary Skill in the Art
`C.
`Petitioner identifies the appropriate level of skill in the art as that
`possessed by a person having “a Bachelor of Science degree in an academic
`discipline emphasizing the design of electrical, computer, or software
`technologies, in combination with training or at least one to two years of
`related work experience with capture and processing of data or information,
`including but not limited to physiological monitoring technologies.” Pet. 7–
`
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`1 Neither party has introduced objective evidence of non-obviousness.
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`8 (citing Ex. 1003 ¶¶ 1–15, 36–37). “Additional education in a relevant field
`or industry experience may compensate for one of the other aspects of the
`[person of ordinary skill in the art] POSITA characteristics stated above.”
`Id.
`
`Patent Owner makes several observations regarding Petitioner’s
`identified level of skill in the art but, “for this proceeding, Masimo
`nonetheless applies Apple’s asserted level of skill.” PO Resp. 21.
`We adopt Petitioner’s assessment as set forth above, which appears
`consistent with the level of skill reflected in the Specification and prior art.
`
`D. Obviousness over Webster and Melby
`Petitioner contends that claim 15 of the ’994 patent would have been
`obvious over the teachings of Webster and Melby. Pet. 29–44; see also Pet.
`Reply 4–5. Patent Owner disagrees. PO Resp. 42–46; see also Sur-reply
`12–15.
`Based on our review of the parties’ arguments and the cited evidence
`in the final record, we determine that Petitioner has met its burden of
`showing by a preponderance of the evidence that claim 15 is unpatentable.
`
`Overview of Webster (Ex. 1010)
`1.
`Webster is a book titled “Design of Pulse Oximeters” that provides an
`overview of the history and design of pulse oximeters, stating that “[p]ulse
`oximetry was introduced in 1983 as a noninvasive method for monitoring
`the arterial oxygen saturation of a patient’s blood.” Ex. 1010, xv2. Webster
`
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`2 Although Petitioner has added page numbering to the bottom of
`Exhibit 1010, Petitioner cites to the original page numbers at the top of the
`book. We adopt Petitioner’s citations for clarity.
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`details “both the hardware and software required to fabricate a pulse
`oximeter as well as the equations, methods, and software required for
`effective functioning” in addition to “testing methods.” Id. Webster
`provides a comprehensive summary of the state of the art as of 1997, and
`also describes the purpose of components of a pulse oximeter as well as the
`design process and selection criteria for particular components. See
`generally Ex. 1010, Chs. 2, 5–7.
`As shown in FIG. 7.1 of Webster, reproduced below, Webster
`explains that the “probe of a pulse oximeter consists of two LEDs of selected
`wavelengths and a detector.” Ex. 1010, 86.
`
`
`Figure 7.1 of Webster depicts a probe using a transmittance principle such
`that light from two LEDs passes alternately through the tissue of the finger
`and is detected by the photodiode. Id. at 87. The LEDs can emit
`wavelengths of, for example, “660 nm and 940 nm,” and “the detector used
`is a photodiode.” Id. at 86. Webster explains that its “photodiode has to
`detect the light transmitted through the tissue” and is “placed in line with the
`LEDs so that the maximum amount of transmitted light is detected.” Id. at
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`87. Because light from the LEDs “is partially reflected, transmitted,
`absorbed, and scattered by the skin and other tissues and the blood before it
`reaches the detector,” reducing the amount of light that eventually reaches
`the detector, the assembly “must be protected from the ambient light for the
`wavelengths to which the photodiode is sensitive.” Id. at 86. Because the
`pulse oximeter “uses two specific wavelengths, spectral response, or the
`relative response of the device to different wavelengths must be considered.”
`Id. at 71 (emphasis omitted).
`Webster describes how the LEDs can be “powered alternately so that
`light of one particular wavelength will pass through the tissue, and the
`transmitted light will be detected by the photodiode” before light of the other
`wavelength is emitted. Ex. 1010, 86. Webster notes that the “intensity of
`the light emerging from the tissue is attenuated by the amount of blood
`present in the tissue.” Id. Because this intensity “varies with the arterial
`pulse,” it can be used “as a measure to indicate the pulse rate.” Id.
`As seen in Figure 7.13 below, Webster describes the importance of
`preventing light other than the actual signals of interest (e.g., light that has
`passed through the tissue carrying pulsing blood) from reaching the detector.
`See Ex. 1010, 95 (describing optical shunting as the condition when light
`from the sensor’s LEDs reaches the photodiode without passing through the
`tissue).
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`Figure 7.13 of Webster depicts light that does not pass through arterioles
`causing optical shunting. Id. Webster states that optical shunting can occur
`“when light from the sensor’s LEDs reaches the photodiode without passing
`through the tissue” and “leads to erroneous readings in the value of SaO2 as
`the amount of light detected by the photodiode is greatly increased by
`optical shunting.” Id.
`Webster proposes that, in order to “minimize the effects from light
`other than the optical signals of interest,” “some type of light filter” can be
`placed over the detector. Id. at 79. Using a light filter allows “light of
`wavelengths of interest to pass through the filter but does not allow light of
`other wavelengths to pass through the filter.” Id. Webster contemplates that
`in order for the pulse oximeter device to function effectively, “most of the
`light being transmitted from the LEDs must not reach the photodiode unless
`it has passed through tissue containing arterial blood.” Id. Indeed, Webster
`discloses that in order to “minimize errors, the pulse oximeter designer must
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`attempt to limit the light reaching the photodiode to that which has traveled
`through tissue containing arterial blood” and suggests that “[l]ight
`impervious barriers should be placed between LEDs and the photodiode in
`all areas where the emitted light could reach the photodiode without passing
`through tissue” containing arterial blood. Id.
`
`Overview of Melby (Ex. 1008)
`2.
`Melby is titled “Light Control Film with Reduced Ghost Images.”
`Ex. 1008, code (54). Melby discloses a light control film, or a “louvered
`plastic film.” Id. at code (57). Melby describes a film that includes “louver
`elements,” and Melby acknowledges that it was known to cant louver
`elements with respect to a louvered plastic film, which produces a film that
`transmits light in a direction other than perpendicular to the surface of the
`film. Id. at 1:9–22, 3:46–62. Melby describes using louvers having an outer
`portion with a relatively low optical density and an inner portion having a
`relatively high optical density. Id. at 3:21–22.
`Melby describes a “louvered plastic film [that] has louvers including
`central regions with a relatively high coefficient[] of extinction and outer
`regions with relatively low coefficients of extinction.” Ex. 1008, code (57).
`As shown in Figures 1 and 2 of Melby, reproduced below, Melby discloses
`“a louvered plastic film has a plurality of clear regions separated by
`louvers,” where each louver has “a central region with a relatively high
`coefficient of extinction and outer regions, adjacent said clear regions,
`having relatively low coefficients of extinction.” Id. at 3:1–8.
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`Figure 1 of Melby depicts a schematic cross section of a louvered
`plastic film and Figure 2 depicts an enlarged drawing of a portion of the
`louvered plastic film. Ex. 1008, 3:10–14. Melby describes its louvered film
`as including “cover sheets 11 provided for clarification and includes
`alternating clear layers, such as layer 12 and louvers, such as louver 14,” that
`“includes outer layers 16 and 18 and inner layer 20.” Id. at 3:46–4:25.
`Referring to Figure 2, Melby describes the operation of the louvers:
`A light ray 22 enters transparent layer 12. It then strikes layer 16
`at surface 24. Because layer 16 has only a low concentration of
`carbon black, there is not a large difference in index of refraction
`between it and layer 12. Therefore very little of the light is
`reflected by layer 24. Most of the light will enter layer 16 and be
`refracted. As the light traverses layer 16, some will be absorbed.
`Some, however, will strike layer 20 on surface 26. Some of light
`beam 22 will enter layer 20 where, due to the relatively high
`concentration of carbon black, it will be absorbed. Some of light
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`beam 22 will be reflected at surface 26 due to the large difference
`in index of refraction between layer 16 and layer 20.
`Ex. 1008, 3:63–4:10.
`
`Independent Claim 15
`3.
`Petitioner contends that claim 15 would have been obvious over
`Webster and Melby. Pet. 29–44. Below, we set forth how the combination
`of prior art references teaches or suggests the claim limitations that are not
`disputed by the parties. For those limitations and reasons for combining the
`references that are disputed, we examine each of the parties’ contentions and
`then provide our analysis.
`
`i. [15 pre] “A sensor which generates at least first and
`second intensity signals from a light-sensitive detector
`which detects light of at least first and second wavelengths
`transmitted through body tissue carrying pulsing blood;
`the sensor comprising:”
`The cited evidence and argument supports Petitioner’s undisputed
`contention that Webster and Melby satisfy the subject matter of the
`preamble. Pet. 30–32. According to Petitioner, Webster describes devices
`known as “pulse oximeters,” which provide “an empirical measure of
`arterial saturation.” Pet. 30 (quoting Ex. 1010, 13). Webster describes the
`operation of the devices as shining “light of two wavelengths through a
`tissue bed such as the finger or earlobe and measures the transmitted light
`signal.” Id. (quoting Ex. 1010, 13).
`Petitioner relies on Webster’s Figure 7.1 as providing detail as to the
`probe of a pulse oximeter.
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`Petitioner’s annotated and highlighted Figure 7.1 of Webster depicts a probe
`using transmittance of light from two LEDs (blue labeled as “Light Emission
`Device”) passing alternately through the tissue of the finger such that it is
`detected by a photodiode (green labeled as “Light Sensitive Detector”).
`Pet. 31; Ex. 1010, 87. Petitioner persuasively relies on Webster’s teaching
`of how the “probe of a pulse oximeter consists of two LEDs of selected
`wavelengths and a detector.” Pet. 31; Ex. 1010, 86. Webster describes how
`the LEDs can emit wavelengths of, for example, “660 nm and 940 nm,” and
`“the detector used is a photodiode.” Ex. 1010, 86.
`Petitioner contends that “[b]ecause light from the LEDs ‘is partially
`reflected, transmitted, absorbed, and scattered by the skin and other tissues
`and the blood before it reaches the detector,’ reducing the amount of light
`that eventually reaches the detector, the assembly ‘must be protected from
`the ambient light for the wavelengths to which the photodiode is sensitive.’”
`Pet. 31–32 (quoting Ex. 1010, 86). Petitioner additionally relies on
`Webster’s teaching that the pulse oximeter “uses two specific wavelengths,
`spectral response, or the relative response of the device to different
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`wavelengths must be considered,” as well as Webster’s teaching that the
`intensity of light emerging from the tissue is attenuated by the amount of
`blood present in the tissue. Ex. 1010, 71; Pet. 32.
`
`Relying on the testimony of Dr. Anthony (Ex. 1003 ¶¶ 76–82),
`Petitioner contends that a person of ordinary skill in the art “would have
`recognized Webster to teach a sensor that generates first and second
`intensity signals from a detector, such as a photodiode,” and further, “[t]he
`photodiode is able to detect, and therefore is sensitive to, light of a first
`wavelength, such as 660 nm, and light of a second wavelength, such as
`940 nm, and such light has been ‘attenuated by the amount of blood present
`in the tissue’ of a subject[].” Pet. 32 (quoting Ex. 1010, 86). Petitioner
`argues, and we agree, that Webster explains the advantages of using two
`different wavelengths to allow pulse oximeters to “determine the oxygen
`saturation of arterial blood” by “using the arterial pulsation to differentiate
`between absorbance of arterial blood and other absorbers.” Pet. 32–33
`(quoting Ex. 1010, 13–14, 44).
`
`We find Petitioner’s contentions set forth above supported by a
`preponderance of the evidence on the final record.
`
`ii.“[a] at least one light emission device;”
`Based on the final record, the cited evidence supports Petitioner’s
`undisputed contention that Webster discloses this limitation. Pet. 33–34.
`Specifically, Webster teaches a sensor that measures first and second
`intensity signals using a photodetector, such as a diode, to detect light from
`at least two LEDs emitting at two different wavelengths. Id. (citing
`Ex. 1010, 13–14, 44, 86, Fig. 7.1).
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`As shown in Figure 7.1 of Webster, reproduced above, Webster
`teaches two light emitting diodes (LEDs highlighted in blue) that emit light
`at two different wavelengths. Thus, we agree with Petitioner that Webster
`teaches at least one light emission device. Ex. 1010, 79 (Fig. 7.1), 13–14;
`Ex. 1003 ¶ 84. We find Petitioner’s contentions supported by the final
`record.
`
`iii. “[b] a light sensitive detector; and;”
`Based on the final record, the cited evidence supports Petitioner’s
`undisputed contentions regarding this limitation. Pet. 35–36. Specifically,
`Petitioner contends that Webster describes a sensor that measures first and
`second intensity signals using a photodetector, such as a diode, to detect
`light from at least two LEDs emitting at two different wavelengths. Pet. 35
`(citing Ex. 1010, 13–14, 44, 56, 86, Fig. 7.1; Ex. 1003 ¶¶ 76–87).
`As shown in Figure 7.1 of Webster, reproduced above, Webster
`teaches a light sensitive photodiode detector (highlighted in green). Pet. 36
`(citing Ex. 1003 ¶ 88). Petitioner relies on Webster’s disclosure that the
`“photodiode has to detect the light transmitted through the tissue” and it is
`“placed in line with the LEDs so that the maximum amount of transmitted
`light is detected.” Ex. 1010, 87; Pet. 36–37 (also discussing Webster’s
`disclosure of “optical shunting” to increase the amount of light detected by
`the photodiode (citing Ex. 1010, 95)).
`
`iv.“[c] a plurality of louvers positioned over the light
`sensitive detector to accept light from the at least one light
`emission device originating from a general direction of the
`at least one light emission device and then transmitting
`through body tissue carrying pulsing blood, wherein the
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`louvers accept the light when the sensor is properly
`applied to tissue of a patient.”
`Petitioner’s Contentions
`Petitioner contends that Webster and Melby teach these limitations.
`Pet. 38–45. Petitioner first notes that Webster proposes the use of a light
`filter to be placed over the detector to minimize the effects from light other
`than the optical signals of interest. Pet. 39 (“Webster proposes that, in order
`to ‘minimize the effects from light other than the optical signals of interest,’
`some type of light filter’ can be placed over the detector.”) (quoting
`Ex. 1010, 79). Specifically, “[u]sing a light filter allows ‘light of
`wavelengths of interest to pass through the filter but does not allow light of
`other wavelengths to pass through the filter.’” Id. (quoting Ex. 1010, 79).
`Petitioner contends that Webster teaches the importance of ensuring
`that light reaching the photodiode must pass through tissue containing
`arterial blood in order for the pulse oximeter to function effectively. Id.
`Petitioner relies on Webster’s disclosure that in order to “minimize errors,
`the pulse oximeter designer must attempt to limit the light reaching the
`photodiode to that which has traveled through tissue containing arterial
`blood” and suggests the use of “[l]ight impervious barriers [that] should be
`placed between LEDs and the photodiode in all areas where the emitted
`light could reach the photodiode without passing through tissue.” Pet. 39
`(quoting Ex. 1010, 79).
`Based on these disclosures, Dr. Anthony testifies that a person of
`ordinary skill in the art would have recognized the advantages of using a
`light filter, such as the type taught by Melby and as suggested by Webster.
`Ex. 1003 ¶¶ 92–96. Dr. Anthony testifies that Melby’s louvered plastic film
`could be used with the combined Webster system as the “light filter” to
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`control light such that only light originating from the direction of the light
`emitters reaches the detector. Id. ¶¶ 96–100; Ex. 1010, 79. Petitioner relies
`on Melby’s teaching of “a ‘louvered plastic film [that] has louvers including
`central regions with a relatively high coefficient[] of extinction and outer
`regions with relatively low coefficients of extinction.’” Pet. 40 (alterations
`in original) (quoting Ex. 1008, code (57)). Further, “Melby teaches ‘a
`louvered plastic film has a plurality of clear regions separated by louvers,’
`where each louver has ‘a central region with a relatively high coefficient of
`extinction and outer regions, adjacent said clear regions, having relatively
`low coefficients of extinction.’” Id. (quoting Ex. 1008, 3:1–8). Petitioner
`points out that Melby’s louvered film includes “cover sheets 11 provided for
`clarification and includes alternating clear layers, such as layer 12 and
`louvers, such as louver 14,” that “includes outer layers 16 and 18 and inner
`layer 20.” Pet. 41 (quoting Ex. 1008, 3:46–4:25).
`Petitioner relies on Melby’s teaching that when “[a] light ray 22
`enters transparent layer 12[,] [i]t then strikes layer 16 at surface 24.”
`Pet. 41 (quoting Ex. 1008, 3:66–67). Petitioner also notes that “very little of
`the light is reflected by layer 24,” instead, “[m]ost of the light will enter
`layer 16 and be refracted.” Id. (quoting Ex. 1008, 3:66–67). According to
`Petitioner, Melby’s “advantage lies with ‘the effective optical density of a
`medium is directly proportional to the distance that the light must travel
`through that