BAE Systems Information and Electronic Systems Integration, Inc.v.Cheetah Omni, LLC

Patent Trial and Appeal Board

Jun 19, 2014

12206432 (P.T.A.B. Jun. 19, 2014)

Trials@uspto.gov Paper 45
571-272-7822 Date: June 19, 2014

UNITED STATES PATENT AND TRADEMARK OFFICE
_____________

BEFORE THE PATENT TRIAL AND APPEAL BOARD
____________

BAE SYSTEMS INFORMATION AND ELECTRONIC SYSTEMS
INTEGRATION, INC.,
Petitioner,

v.

CHEETAH OMNI, LLC,
Patent Owner.
____________

Case IPR2013-00175
Patent 7,633,673 B1
____________

Before STEPHEN C. SIU, JUSTIN T. ARBES, and RAMA G. ELLURU,
Administrative Patent Judges.

ELLURU, Administrative Patent Judge.

FINAL WRITTEN DECISION
35 U.S.C. § 318(a) and 37 C.F.R. § 42.73

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I. BACKGROUND
Petitioner, BAE Systems Information and Electronic Systems Integration,
Inc. (“BAE”), filed a petition on March 4, 2013, requesting inter partes review of
claims 1, 4, 13–15, 17, and 19 of U.S. Patent No. 7,633,673 B1 (“the ’673 patent”).
(Paper 1, “Pet.”). Patent Owner, Cheetah Omni, LLC (“Cheetah”), filed a
preliminary response opposing institution of review. Paper 12. On July 3, 2013,
we instituted an inter partes review of claims 1, 4, 13–15, 17, and 19 of the ’673
patent (Paper 15) (“Dec. on Inst.”).
Subsequent to institution, Cheetah filed a Patent Owner Response (Paper 27)
(“PO Resp.”), and BAE filed a Reply (Paper 30) (“Pet. Reply”). Along with its
Patent Owner Response, Cheetah filed a Motion to Amend (Paper 28) (“Mot.”).
BAE filed an Opposition to Cheetah’s Motion to Amend (Paper 31) (“Opp.”), and
Cheetah filed a Reply in support of its Motion (Paper 32) (“PO Reply”). BAE
initially requested an oral hearing, which we granted, and Cheetah did not file a
request for oral argument. Papers 43, 44. BAE subsequently contacted the Board
to indicate its belief that a hearing was not necessary. Paper 44. Based on the
parties’ representations, we determined that a hearing was not necessary for a
decision in this trial. Id.
The Board has jurisdiction under 35 U.S.C. § 6(c). This final written
decision is issued pursuant to 35 U.S.C. § 318(a) and 37 C.F.R. § 42.73.
For the reasons that follow, we determine that BAE has shown by a
preponderance of the evidence that claims 1, 4, 13–15, 17, and 19 of the ’673
patent are unpatentable, and we deny Cheetah’s Motion to Amend.

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A. The ʼ673 Patent
The ʼ673 patent is directed to systems and methods for generating infrared
light with wavelength in the mid-infrared (IR) range. Ex. 1001, Title, Abstract.
Some of the embodiments described by the ’673 patent use a Raman wavelength
shifter that is coupled to a pump laser to produce a longer wavelength. Ex. 1001,
14:65–67. A “Raman wavelength shifter” refers to any device that uses the Raman
effect to shift a shorter optical signal wavelength to a longer optical signal
wavelength. Ex. 1001, 15:1–3. “Raman effect” is caused by inelastic scattering of
a photon during an interaction with an atom or molecule, causing the photon to
gain or lose energy with a corresponding decrease or increase in wavelength,
respectively. Pet. 13 (citing Ex. 1013).

B. Challenged Claims
Claims 1 and 13 are independent claims. The remaining challenged claims
depend from either claim 1 or claim 13. Claim 1 is representative of the
challenged claims and is reproduced below.
1. A mid-infrared light source, comprising:
a multiplexer operable to combine a first laser signal and a
second laser signal to generate a first optical signal, the first optical
signal comprising one or more wavelengths;
a gain fiber coupled to the multiplexer and operable to receive
at least the first optical signal, the gain fiber comprising a first
waveguide structure;
a second waveguide structure coupled to the gain fiber and
operable to wavelength shift at least one wavelength of the first
optical signal to a longer wavelength optical signal, the longer
wavelength optical signal comprising a wavelength in the range of 1.7
microns or more, the second waveguide structure comprising a
wavelength shifting fiber coupled to a nonlinear element, wherein the
wavelength shifting fiber operates to wavelength shift the at least one
wavelength of the first optical signal to a second optical wavelength
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and the nonlinear element operates to wavelength shift the second
optical wavelength to the longer wavelength optical signal, and
wherein the wavelength shifting fiber is substantially different than
the nonlinear element.

C. Prior Art
The pending grounds of unpatentability in this inter partes review are based
on the following prior art.
Patent No. Filing Date Issue Date Exhibit No.
6,229, 828
(“Sanders”)
July 27, 1998 May 8, 2001 1010

Pet. 8. BAE also relies on a declaration submitted by David A. Smith, Ph.D.
(“Smith Decl.”) (Ex. 1011).

D. Pending Grounds of Unpatentability
We instituted an inter partes review of the ’673 patent based on the
following grounds:
1. Claims 1, 4, 13, 15, 17, and 19 as anticipated by Sanders under
35 U.S.C. § 102(b); and
2. Claim 14 as unpatentable over Sanders under 35 U.S.C. § 103(a).
Dec. on Inst. 20.

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II. ANALYSIS
A. Claim Construction
Consistent with the statute and the legislative history of the AIA, the Board
interprets claims by applying the broadest reasonable construction in the context of
the specification in which the claims reside. 37 C.F.R. § 42.100(b); see Office
Patent Trial Practice Guide, 77 Fed. Reg. 48,756, 48,766 (Aug. 14, 2012). The
words of the claim will be given their plain meaning unless the plain meaning is
inconsistent with the specification. In re Zletz, 893 F.2d 319, 321 (Fed. Cir. 1989).
“There are only two exceptions to the general rule that a claim term is given its
ordinary meaning: 1) when a patentee sets out a definition and acts as his own
lexicographer, or 2) when the patentee disavows the full scope of a claim term
either in the specification or during prosecution.” See Thorner v. Sony Computer
Entm’t Am. LLC, 669 F.3d 1362, 1365 (Fed. Cir. 2012). “Although an inventor is
indeed free to define the specific terms used to describe his or her invention, this
must be done with reasonable clarity, deliberateness, and precision.” In re
Paulsen, 30 F.3d 1475, 1480 (Fed. Cir. 1994). Also, we must be careful not to
read a particular embodiment appearing in the written description into the claim if
the claim language is broader than the embodiment. See In re Van Geuns, 988
F.2d 1181, 1184 (Fed. Cir. 1993) (“limitations are not to be read into the claims
from the specification”).
1. “Gain fiber”
Independent claims 1 and 13 require “a gain fiber coupled to the multiplexer
and operable to receive at least the first optical signal.”
In our Decision to Institute, based on testimony by BAE’s declarant and the
’673 patent Specification, we interpreted “gain fiber” in claims 1 and 13 as “an
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optical fiber that functions as a gain medium (i.e., amplifies an input signal).”
Dec. on Inst. 10.
Cheetah argues that our construction improperly narrows the claims. PO
Resp. 3, 12. In support, Cheetah states that the claim language contains no
limitation indicating that the gain fiber is functioning as a gain medium. Id. at 12.
According to Cheetah, the patentee has acted at least partially as his own
lexicographer. Id. at 13. Cheetah points to disclosure from the ’673 patent
Specification stating that “a gain fiber 804 [is] operable to facilitate shifting pump
signal 810 to a desired wavelength,” “[g]ain fiber 804 may comprise any
waveguide structure capable of wavelength shifting pump signal 810 to a longer
wavelength,” and “[i]n this particular embodiment, gain fiber 804 comprises an
optical fiber.” Id. at 12–13 (citing Ex. 1001, 17:18–27). With respect to the part
of our construction “(i.e., amplifies an input signal),” Cheetah notes that the ’673
patent Specification does not contain the terms “amplify or “amplifies.” Id. at 13.
Cheetah’s proposed construction for “gain fiber” is “an optical fiber
comprising any waveguide structure.” Id. at 14. According to Cheetah, its
proposed construction includes language from the Specification, and is broad
enough to include the teachings in the Specification and the understanding of a
person of ordinary skill in the art as attested to by BAE. Id.
BAE responds that Cheetah’s proposed construction renders the term “gain”
surplusage because that construction does not require amplification of the input
signal. Pet. Reply 9–10 (citations omitted). Further, BAE notes that the ’673
patent Specification states that “gain fiber 804” is a “gain medium.” Id. at 10.
Cheetah does not address this disclosure from the specification. See PO Resp. 12–
13.
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Cheetah’s proposed construction is incorrect because the ’673 patent
Specification does not limit “gain fiber” to a waveguide structure, but rather
discloses that a gain fiber “may comprise” any waveguide structure. Ex. 1001,
17:18–27. We further agree that Cheetah’s proposed construction for “gain fiber”
would read out the term “gain.”1 See Pet. Reply 9–10. BAE’s declarant states that
“gain fiber” would have been understood by a person of ordinary skill in the art to
mean “an optical fiber that operates to amplify an input signal.” Ex. 1011 ¶ 22.
Cheetah does not contest this testimony. See PO Resp. 13. As we noted in our
Decision (Dec. on Inst. 10), the ’673 patent Specification’s disclosure of “gain
fiber” is consistent with this ordinary meaning. In particular, the ’673 patent
Specification refers to “[g]ain fiber 804” as a “gain medium.” Ex. 1001, 17:18–27,
17:42. As Cheetah notes, however, the ’673 patent Specification states that the
gain fiber is “operable” to facilitate shifting a signal to a desired wavelength. Id. at
17:18–27.
Accordingly, we modify our initial construction of “gain fiber,” and interpret
the term to mean “an optical fiber that is operable as a gain medium (i.e., amplifies
an input signal).”
2. Other Terms
In the Decision on Institution, we interpreted one other claim term as
follows. We interpreted “wavelength shift,” appearing in claims 1 and 13, as
“receiving at least one input wavelength and emitting at least one output
wavelength that is different from the input wavelength.” Dec. on Inst. 10–11.
Neither party disputes that interpretation, and we apply it in this decision, for the
reasons stated in the Decision on Institution.

1 Moreover, as discussed below, even if we were to adopt Cheetah’s proposed
construction of “gain fiber,” it would not change our analysis.
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B. Anticipation by Sanders (Ex. 1010)
With respect to our review of BAE’s contention that claims 1, 4, 13, 15, 17,
and 19 are anticipated by Sanders, we have reviewed BAE’s Petition, Cheetah’s
Patent Owner Response, and BAE’s Reply, as well as the evidence discussed in
each of those papers. We are persuaded by a preponderance of the evidence that
claims 1, 4, 13, 15, 17, and 19 are anticipated by Sanders. See Pet. 15–27, 28–30,
32–44 (claim charts).
Claim 13
Cheetah argues that Sanders’s nonlinear frequency mixing (“NFM”) device
(element 114 of Figure 19) does not satisfy the claimed “nonlinear oscillator” of
independent claim 13, and thus, Sanders does not anticipate claims 13 or its
dependent claims. PO Resp. 3, 8. Claim 13 recites “the wavelength shifting
structure comprising a wavelength shifting fiber coupled to a nonlinear oscillator.”
Cheetah also notes that claim 4, depending from claim 1, further limits the recited
“nonlinear element” of claim 1 to be a “nonlinear oscillator.” Id.
BAE contends that Sanders’s NFM device 114, illustrated in Figure 19,
corresponds to the recited “nonlinear oscillator” of claim 13. Pet. 26. BAE notes
that Sanders states that NFM device 114 shown in Figure 19 may be a quasi-phase
matching (QPM) optical parametric oscillation (OPO) device. Id. (citing Ex. 1010,
21:1–3) (emphasis added); see Ex. 1010, 8:13–14. Sanders expressly states the
following.
The combined outputs of wavelengths λ1 and λ2 from Raman fiber
oscillator 112 is provided as input to NFM device 114, e.g., QPM
DFM or QPM OPO devices.

Ex. 1010, 21:1–3. Figure 19 of Sanders is reproduced below.
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Figure 19 illustrates NFM device 114.
Cheetah argues that Sanders’s NFM device 114 is a QPM difference
frequency mixing (“DFM”) device, not a QPM OPO device, as BAE asserts. PO
Resp. 3–8. Cheetah states that a QPM DFM device accepts light at two
wavelengths and mixes them to produce light at a third wavelength (two input
wavelengths and one output wavelength), whereas a QPM OPO device accepts
light at one wavelength and mixes it with internally generated light at a second
wavelength to produce light at the third wavelength (one input wavelength and one
output wavelength). PO Resp. 5–6. Cheetah states that a NFM device comprising
a QPM DFM device is illustrated in Figure 1A of Sanders. Id. at 4 (citing Ex.
1010, 6:50–7:13); see Ex. 1016 ¶ 4. Figure 1A of Sanders is reproduced below.

Sanders explains that Figure 1A illustrates a NFM device comprising a QPM DFM
device wherein beams λ1 and λ2 from two different light sources are combined and
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provided as input to QPM DFM device 16, which generates a frequency mixed
beam having wavelength λ3. Ex. 1010, 6:50–7:13. Cheetah states that a NFM
device comprising a QPM OPO device is illustrated in Figure 1D. PO Resp. 5
(citing Ex. 1001, 8:8–20); see Ex. 1016 ¶ 4. Figure 1D is reproduced below.

Sanders explains, with respect to Figure 1D, that pumping source 10 having a
pumping wavelength λ1 is coupled to NFM device 16 comprising a QPM OPO
device, which functions as an “oscillator creating within its optical cavity a second
shifted wavelength, λ2, which is difference frequency mixed” with pumping
wavelength λ1 to produce wavelength λ3. Ex. 1010, 8:8–20.
According to Cheetah, the NFM device of Figure 19 is an embodiment of a
QPM DFM, illustrated in Figure 1A because there are two input wavelengths, λ1
and λ2. PO Resp. 6-7. Cheetah emphasizes (id.) the following disclosure from
Sanders relating to Figure 19.
The output from Raman fiber oscillator 112 is coupled into NFM
device 114 for mixing of combined wavelengths λ1, λ2, i.e., is the
difference between the Raman shifted beam and the transmitted pump
beam from source 61.

Ex. 1010, 21:9–13. Thus, according to Cheetah, NFM device 114 has light at λ1
and λ2 as its input, and mixes them to produce light at wavelength λ3. PO Resp. 7.
According to Cheetah, it is consistent with Figure 1A for Sanders to state that
NFM device 114 could be a QPM DFM device, but that it was a “drafting error” to
imply that NFM device 114 could be a QPM OPO because Sanders does not teach
a QPM OPO that mixes two inputs λ1 and λ2. Id.
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Cheetah further argues that Figure 15 of Sanders affirms that a QPM OPO
device mixes one input at λ1 with internally generated light at λ2. Id. at 7–8.
Figure 15 of Sanders is reproduced below.

Figure 15 includes QPM OPO device 74. Ex. 1010, 18:48–65. Sanders states that
wavelength λ1 is coupled into OPO resonator 74, which includes external cavity
focusing mirrors 73 and 75. Id. Mirror 73 is transparent to wavelength λ1, but is
highly reflective of internally developed wavelength λ2, whereas mirror 75 is
transparent to developed wavelength λ3, and highly reflective of internally
developed wavelength λ2. Id. Thus, contends Cheetah, the NFM components of
Figures 15 and 19 are not combinable because inserting the Figure 15 QPM OPO
into the Figure 19 system results in the Figure 19 λ2 being reflected back into the
fiber by mirror 73 and discarded. PO Resp. 8. Cheetah states that “[i]n no case
would the QPM OPO of Fig. 15 mix λ1 with Fig. 19 λ2.” Id.
We agree with BAE that Cheetah’s attorney argument is not persuasive. See
Pet. Reply 1. Instead, we are persuaded by the express disclosure of Sanders that
NFM device 114 may be a QPM DFM or QPM OPO device, and do not view that
express disclosure as merely a drafting error, as Cheetah suggests. Ex. 1010, 21:1–
3 (“NFM device 114, e.g., QPM or QPM OPO devices”). We further find
persuasive BAE’s testimony from Dr. David A. Smith that a person of ordinary
skill in the art would understand that a QPM DFM device and QPM OPO device
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operate fundamentally in the same way—“by mixing two wavelengths to generate
a third wavelength,” and only differ with regard to the source of the second
wavelength. Ex. 1016 ¶ 4. Dr. Smith’s uncontested testimony is that a person of
ordinary skill in the art would recognize that NFM device 114, illustrated in Figure
19, can function as a QPM OPO device (as Sanders expressly states) by using
wavelength λ2 as the input wavelength to NFM device 114, internally generating
another wavelength λ4 (not shown), and mixing λ2 with λ4 to generate λ3. Ex. 1016
¶ 6.2
Dr. Smith further refers to Figure 153 to explain that the additional input
wavelength λ1, as illustrated in Figure 19, would not adversely affect the
conversion of the wavelength λ2 by the NFM device functioning as a QPM OPO
device. Id. According to Dr. Smith, the QPM OPO device, illustrated as element
74 in Figure 15, may include crystal 72 for phase matching the input wavelength.
Id. (citing Ex. 1010, 18:57–60). For example, asserts Dr. Smith, crystal 72 could
be designed to receive the second wavelength λ2 (1.44 μm), generate the internal
wavelength λ4 (e.g., 2.25 μm), and mix λ2 with λ4 to generate the third wavelength
λ3 (e.g., 4.0 μm). Id. (citing Ex. 1010, 19:3–9, 2:59–62, 7:63–67). As Dr. Smith
explains, a person of ordinary skill in the art would understand that λ1 would have
no effect on the wavelength conversion from λ2 to λ3, because phase matching
would not occur for λ1 if crystal 72 was designed to phase match with wavelength
λ2. Id. Thus, we determine that Sanders discloses NFM device 114, illustrated in

2 BAE notes that in Figures 1D and 15 of Sanders, the input wavelength to the
NFM device is λ1, the mixing wavelength is λ2, and the NFM output wavelength is
λ3, whereas in Figure 19 the input wavelength is λ2, the mixing wavelength is λ4
(not shown), and the NFM output wavelength is λ3. Pet. Reply 3 n.1.
3 Figure 15 is a NFM device that operates as a QPM OPO device. Ex. 1010,
18:46–49.
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Figure 19 of Sanders, as a QPM OPM device. Cheetah has not disputed that a
QPM OPM device satisfies the claimed “nonlinear oscillator” of independent claim
13.
Cheetah further argues that Sanders does not disclose the limitations that
“the wavelength shifting fiber operates to wavelength shift the at least one
wavelength . . . to a second optical wavelength,” and that “the nonlinear oscillator
operates to wavelength shift the second optical wavelength” to a third wavelength,
as recited in claim 13. PO Resp. 10. Cheetah asserts that Sanders discloses
shifting only “a portion” of the radiation beam at wavelength λ1 from the pump
source to a second wavelength λ2, and that the output from Raman fiber oscillator
112 is coupled into NFM device 114 for “‘mixing of combined λ1, λ2.’” Id.
(quoting Ex. 1010, 20:63–21:11) (emphasis omitted). Cheetah contends that
Sanders teaches a different system than the one recited in claim 13, where Raman
fiber oscillator 112 shifts only a portion of its input wavelength because NFM
mixing device 114 needs both λ1 and λ2. Id. at 11.
We are not persuaded by Cheetah’s argument. Cheetah has not shown that
the limitations require shifting the entire wavelength, as opposed to a portion of
the wavelength, as admittedly disclosed by Sanders. See id. at 10–11.
Furthermore, Cheetah’s argument that Sanders discloses a NFM device that mixes
two input wavelengths, λ1 and λ2, as opposed to a nonlinear oscillator that shifts a
second wavelength to a third wavelength as claimed, is based on its assertion that
NFM device 114 is a QPM DFM device (id. at 11). As discussed above, we
determine that NFM device 114 is not limited to a QPM DFM device.
Furthermore, our construction of “gain fiber” does not affect our finding that
Sanders discloses the claimed “gain fiber.” Dec. on Inst. 12–13. As we found in
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our Decision on Institution, fiber amplifier 69A, illustrated in Figure 11,4 receives
the optical signal from the beam combiner 67A, amplifies the signal, and further
guides the received signal into the inner cladding 69C and core 69B of first
amplifier 69A, and thus, satisfies the “gain fiber” limitation. See Ex. 1010, Fig. 11,
16:22–28, 17:12–19.
Claim 1
Claim 1 recites “the nonlinear element operates to wavelength shift the
second optical wavelength to the longer wavelength optical signal.” Cheetah
argues that Sanders does not anticipate claim 1 based on the same arguments
asserted in support of claim 13. Specifically, Cheetah contends that Sanders does
not teach the claimed “nonlinear element” of claim 1. PO Resp. 11. For the
reasons discussed above, we do not find those arguments persuasive.
BAE further contends that even if the NFM device 114 of Figure 19 is a
QPM DFM device, it corresponds to the recited “nonlinear element” of claim 1.
Pet. Reply 7–8. We agree. Sanders explains that the output from fiber oscillator
112, λ1 and λ2, is input into NFM device 114 for mixing of the combined
wavelengths to output a resulting wavelength. Ex. 1010, 21:9–18. As an example,
wavelength λ1 may be between about 1030 nm to 1090 nm, and wavelength λ2 may
be between about 1.44 µm, and the resulting wavelength after mixing will be a
mid-IR wavelength between about 3.6 nm and 4.5 nm.5 Id. at 21:13–18. BAE
asserts that as its name indicates, the “nonlinear” frequency mixing device, i.e.,

4 High power source 61 illustrated in Figure 11, which includes fiber amplifier
69A, is incorporated into Figure 19. Ex. 1010, Figs. 11, 19.
5 BAE notes that there is a typographical error in Sanders because although
Sanders states that the resulting wavelength after mixing is between approximately
3.6 nm and 4.5 nm, Sanders states that the resulting wavelength is a “mid-IR
wavelength,” and thus, the units are µm, and not nm. Pet. Reply 8 n.4 (citing Ex.
1010 at 21:17–18).
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NFM device 114, is a “nonlinear element,” as recited in claim 1, and it shifts
wavelength λ2 from approximately 1.44 µm to a longer wavelength of
approximately 3.6 µm to 4.5 µm. Pet. Reply 8. Dr. Smith’s testimony supports
BAE’s argument that NFM device 114 satisfies the “nonlinear element” recited in
claim 1. Ex. 1011 ¶ 33. Therefore, we determine that BAE has shown by a
preponderance of the evidence that even if NFM device 114 is a QPM DFM
device, it satisfies the recited “nonlinear element” of claim 1.
BAE’s Reply also refers to Figure 20 of Sanders as describing all of the
limitation of claims 1, 4, 13, 15, 17, and 19. Pet. Reply 5–7. Although BAE cited
Figure 20 in its Petition, it did not develop this particular argument in its Petition.
See e.g., Pet. 20, 32–35 (claim chart for claim 1 showing that Sanders discloses the
limitations of claims, 1, 4, 13, 15, 17, and 19). Thus, given that this is a newly
raised argument, we decline to consider this argument in this decision. See 37
C.F.R. § 42.23(b) (“A reply may only respond to arguments raised in the
corresponding opposition or patent owner response.”)
Conclusion
Accordingly, based on the record evidence, in light of the arguments
presented, BAE has shown, by a preponderance of the evidence, that independent
claims 1 and 13, as well as claims 4, 15, 17, and 19 depending therefrom, are
anticipated by Sanders.
C. Obviousness Over Sanders (Ex. 1010)
With respect to our review of BAE’s contention that claim 14 is rendered
obvious by Sanders, we have reviewed BAE’s Petition, Cheetah’s Patent Owner
Response, and BAE’s Reply, as well as the evidence discussed in each of those
papers. Cheetah does not raise any arguments with respect to BAE’s challenge
that claim 14 is rendered obvious by Sanders. See PO Resp. 2–3. We are
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persuaded, by a preponderance of the evidence, that claim 14 would have been
obvious over Sanders. See Pet. 40–41 (claim charts).
D. Cheetah’s Motion to Amend
Cheetah filed a Motion to Amend Claims. In its motion to amend, Cheetah
proposes substitute claims 21–26, to replace claims 1, 4, 13, and 15. Mot. 2.
Cheetah’s motion is contingent, meaning that a proposed substitute claim is at
issue and would be considered only if the claim it replaces, i.e., an original claim
or a prior proposed substitute claim, is found unpatentable. Id. Specifically,
Cheetah proposes the following.
If [claim 1] is found unpatentable, please replace claim 1 with
substitute claim 21. If substitute claim 21 is found unpatentable,
please replace claim 1 . . . with substitute claim 22. If claims 21 and 4
are both found unpatentable, please replace claim 4 with substitute
claim 23. If claim 13 is found unpatentable, please replace claim 13
with substitute claim 24. If substitute claim 24 is found unpatentable,
please replace claim 13 . . . with substitute claim 25. If claims 24 and
15 are found unpatentable, please replace claim 15 with substitute
claim 26.
Id. Because we have determined that original claims 1 and 13 are unpatentable, we
reach the merits of Cheetah’s motion.
As the moving party, Cheetah bears the burden of proof to establish that it is
entitled to the relief requested. 37 C.F.R. § 42.20(c). Entry of the proposed
amendments is not automatic, but only upon Cheetah having demonstrated the
patentability of those claims.
Cheetah’s proposed substitute claims 21 and 22 are illustrative of the
proposed substitute claims. Substitute claims 21 and 22, with the new claim
language added to original claim 1 underlined, are reproduced below.
21. A mid-infrared light source, comprising:
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a multiplexer operable to combine a first laser signal and a
second laser signal to generate a first optical signal, the first optical
signal comprising one or more wavelengths;
a gain fiber coupled to the multiplexer and operable to receive
at least the first optical signal, the gain fiber comprising a first
waveguide structure;
a second waveguide structure coupled to the gain fiber and
operable to wavelength shift at least one wavelength of the first
optical signal to a longer wavelength optical signal, the longer
wavelength optical signal comprising a wavelength in the range of 1.7
microns or more, the second waveguide structure comprising a
wavelength shifting fiber coupled to a Q-switcher further coupled to a
nonlinear element, wherein the wavelength shifting fiber operates to
wavelength shift the at least one wavelength of the first optical signal
to a second optical wavelength and the nonlinear element operates to
wavelength shift the second optical wavelength to the longer
wavelength optical signal, and wherein the wavelength shifting fiber
is substantially different than the nonlinear element.

22. A mid-infrared light source, comprising:
a multiplexer operable to combine a first laser signal and a
second laser signal to generate a first optical signal, the first optical
signal comprising one or more wavelengths;
a gain fiber coupled to the multiplexer and operable to receive
at least the first optical signal, the gain fiber comprising a first
waveguide structure;
a second waveguide structure coupled to the gain fiber and
operable to wavelength shift at least one wavelength of the first
optical signal to a longer wavelength optical signal, the longer
wavelength optical signal comprising a wavelength in the range of 1.7
microns or more, the second waveguide structure comprising a
wavelength shifting fiber coupled to a Q-switcher further coupled to a
nonlinear element, wherein the wavelength shifting fiber operates to
wavelength shift the at least one wavelength of the first optical signal
to a second optical wavelength and the nonlinear element operates to
wavelength shift the second optical wavelength to the longer
wavelength optical signal, and wherein the wavelength shifting fiber
is substantially different than the nonlinear element, and wherein the
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Q switcher produces an output signal having a pulse width in the
range of two (2) nanoseconds to one hundred (100) milliseconds.

1. Written Description Support
Cheetah’s substitute claim 21 is identical to original claim 1, except for the
additional recital that the second waveguide structure comprises “a wavelength
shifting fiber coupled to a Q-switcher further coupled to a nonlinear element.”
Substitute claim 22 adds the same limitation, and also adds the limitation “and
wherein the Q switcher produces an output signal having a pulse width in the range
of two (2) nanoseconds to one hundred (100) milliseconds.” Mot. 3–7.
In its motion, Cheetah contends that the subject matter of its proposed
substitute claims have written description support in the specification of the ’673
patent. Mot. 7. Rules 42.121(b)(1) and (2), however, require that a motion to
amend set forth the support in the original disclosure of the patent for each claim
that is added and the support in an earlier-filed disclosure for each claim for which
the benefit of the filing date of the earlier filed disclosure is sought. 37 C.F.R.
§ 42.121(b)(1), (2). For written description support for the proposed substitute
claims, Cheetah refers to portions of the ’673 patent Specification only for the
added limitations in its proposed substitute claims. Specifically, Cheetah refers to
Figure 8D, and column 19, lines 20–39 of the ’673 patent Specification. Mot. 7.
Such reference does not satisfy the requirements of Rule 42.121(b)(1) because the
specification is not the original disclosure. Moreover, Cheetah cites alleged
support in the specification for only the added Q-switcher limitations. Cheetah
does not identify support in the original disclosure “for each claim” in its motion to
amend, as a whole and including the Q-switcher limitations, as required by Rule
42.121(b)(1). Cheetah, therefore, has not made a sufficient showing that its
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proposed substitute claims, as a whole, have written description support in the
original disclosure of the ’673 patent, and we deny the motion on that basis.
2. Patentability of Substitute Independent Claims 21 and 24
Even if Cheetah had satisfied the requirement to show sufficient written
description support, it has not shown that proposed substitute claims 21 and 24 are
patentable. In its motion, Cheetah states that in the related litigation in the United
States Court of Federal Claims, BAE provided Cheetah with prior art references.
Mot. 9.6 Cheetah asserts that it searched those prior art references for the term “Q
switch,” and argues that those references disclose broad coverage of the use of Q-
switchers, at a different point in their disclosed devices and for different purposes
than those of the ’673 patent. Id. According to Cheetah, those references teach
using Q-switchers within laser sources (e.g., Sanders’s Fig. 11, element 66A) or
within a pump laser source (e.g., Sanders’s Fig. 11, element 65A). Id. at 10–11.
We are not persuaded, however, that Cheetah has met its burden to show that
proposed substitute claims 21 and 24 would have been unpatentable over the prior
art. BAE, in opposing Cheetah’s motion, cites the following additional prior art
reference in addition to Sanders (Ex. 1010): G.P. Lees, 980 nm diode pumped
erbium3+/ytterbium3+ doped Q-switched fibre laser, Electronic Letter, Vol. 31, No.
21, 1836–37 (October 1995) (“Lees”) (Ex. 1018). Opp. 7. BAE argues that
Sanders and Lees, in combination, teach all of the limitations of claims 21 and 24,
and that a person of ordinary skill in the art would have had reason to modify
Sanders to incorporate a Q-switcher in the recited position, as taught by Lees. Id.

6 We note that distinguishing the proposed claims only from the prior art references
applied to the original patent claims is insufficient to demonstrate patentability
over the prior art. See Idle Free Sys. v. Bergstrom, Inc., IPR2012-00027, Paper 26
at 7 (June 11, 2013) (patent owners must consider and distinguish “prior art,” both
“of record” and “not of record but known to the patent owner”).
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7–13. BAE’s arguments are supported by the testimony of Dr. David A. Smith.
See Ex. 1017 ¶¶ 5–11.
Q-Switcher
Cheetah refers to the following disclosure from U.S. Patent No. 7,286,587
(Ex. 2009) for a description of a Q-switcher. Mot. 8.
Q-switching is a technique used to obtain high peak power laser
pulses. Q-switching is performed by controlling Q-switching
oscillation to modulate the losses in a resonator cavity 11 by abruptly
changing a loss of resonant laser light passing through resonator
cavity 11. Acousto-optic Q-switches are well known in the art, are
often made from fused silica or crystal quartz, and are powered from
an RF source connected to a transducer mounted to the silica substrate
of the Q-switch.

Ex. 2009, 5:42–50.
Sanders
Figure 16 of Sanders shows a mid-IR light source that uses high power
source 61 and is similar to the mid-IR light source shown in Figure 19, which we
discussed above. Ex. 1010, Figs. 16, 19. In particular, Figure 16 includes the
same components as Figure 19, except that fiber oscillator 112 of Figure 19 is
replaced by fiber laser 82 of Figure 16. Id. at 19:10–15, 22:23–25. Figure 16 of
Sanders is reproduced below.

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Sanders explains in relation to Figure 16 that if the first wavelength λ0 from fiber
amplifier 69A is approximately 910 nm, fiber laser 82 shifts the first
wavelength λ1 to a second wavelength λ2 of approximately 1155 nm. Id. at 19:41–
49. We, thus, agree with BAE (Opp. 9) that fiber laser 82 is a “wavelength shifting
fiber” as recited in proposed claims 21 and 24. Further, fiber laser 82 is coupled to
NFM device 84, which shifts the second wavelength λ2 to a longer wavelength λ3 in
the mid-IR region, such as approximately 4.3 μm. Id. at 19:29–33, 41–49, 55–62.
Sanders states that NFM device 84 may be a QPM OPO device. Id. at 20:7–8.
Accordingly, based on the disclosure of Sanders and our discussion above as to
how NFM device 114 in Figure 19 describes a QPM OPO device, we agree with
BAE (Opp. 9–10) that NFM device 84 is a “nonlinear oscillator” as recited in
proposed substitute claim 24, and a “nonlinear element” as recited in proposed
substitute claim 21.
Lees
Lees describes a fiber laser that includes an Er:Yb codoped fiber surrounded
by an input mirror and an output mirror. Ex. 1018, p. 1836 (right hand column,
first full paragraph); Fig. 1. In order to “Q-switch” the laser, an acousto-optic
modulator (AOM) is introduced into the laser cavity between an end of the fiber
and the output mirror. Id. at Fig. 1; p. 1836 (right hand column, third full
paragraph). The Q-switched fiber laser provides laser pulses having a peak power
over 50 W, with a pulse width of 15 ns and a pulse repetition rate of 500 Hz. Id.
Analysis
We are persuaded by BAE’s arguments (Opp. 11) that it would have been
obvious to a person of ordinary skill in the art to modify Sanders to couple a Q-
switcher with fiber laser 82 shown in Figure 16 based on the teachings of Lees.
See Ex. 1017 ¶¶ 8–11. As Cheetah acknowledges (Mot. 8), Q-switchers were
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known in the art and used to obtain high peak power laser pulses. Lees teaches a
Q-switcher, the AOM, within the laser cavity of the Er:Yb fiber laser. Ex. 1018,
Fig. 1; p. 1836 (right hand column, first full paragraph); Ex. 1017 ¶ 9. Sanders
explains that high peak power laser pulses are advantageous for pumping a QPM
OPO device, such as Sanders’s NFM device 84. Ex. 1010, 1:40–44, 3:21–27,
17:42–49. We, thus, are persuaded by Dr. Smith’s testimony that it would have
been obvious to a person of ordinary skill to provide high peak power pulses to
NFM device 84 by arranging Lees’s AOM (i.e., a Q-switcher) within Sanders’s
fiber laser 82 in a manner described by Lees. Ex. 1017 ¶¶ 9–10. As BAE asserts,
the reason to combine would have been to provide high peak power laser pulses
from fiber laser 82 to NFM device 84. See id. ¶¶ 9–11. We further are persuaded
that there would have been a reasonable expectation of success for modifying
Sanders based on Lees, in view of the similarities between the fiber laser 82 of
Sanders and the Q-switched fiber laser of Lees. See id. ¶¶ 10–11.
Cheetah, in its Reply to BAE’s opposition to the motion to amend, argues
that the substitute claims are non-obvious over the combination of Sanders and
Lees. PO Reply 4–6. In support of its Reply, Cheetah submits the declaration
testimony of Dr. Erich Ippen. Ex. 2013.7 Cheetah summarily asserts that Dr.
Ippen shows that the combination proposed by BAE would not work because light
beam λ2 is generated only to be reflected back at reflector 73. PO Reply 5.
Cheetah has not directed us to sufficient evidence to demonstrate that
substitute claims 21 and 24 would not have been obvious over the combination of

7 Patent Owner was authorized to file a replacement declaration from Dr. Ippen as
supplemental evidence. Paper 35 at 4. Cheetah asserts that the replacement
declaration, Exhibit 2013, is identical to Exhibit 2010 except for portions of the
text being blacked out, a different date, and Dr. Ippen’s newly affixed signature
indicating that he has reviewed and approved Exhibit 2013. Paper 36 at 2.
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Sanders and Lees. First, the Board has made clear, and we agree, that “a party may
not make its case within the declaration of an expert and state in the motion itself
that readers simply should refer to the presentation in the declaration.” ZTE Corp.
v. Contentguard Holdings, Inc., IPR2013-00136 (Paper 31 at 2) (Nov. 5, 2013). It
is improper for any argument to be fully developed and presented, not in the
party’s paper itself, but in the declaration of an expert. Id. at 2–3. Here, Cheetah’s
Reply does not present any argument as to why the combination proposed by BAE
would not work, but rather merely cites to the declaration of Dr. Ippen. PO Reply
5; see 37 C.F.R. § 42.6(a)(3) (arguments must not be incorporated by reference
from one document into another document). Second, Dr. Ippen’s contentions that
the proposed combinations would not work refer to the reflection of λ2 by reflector
73, which is located in Figure 15, while BAE’s proposed combination refers to
Figure 16 of Sanders. See Ex. 2010 ¶ 8; Opp. 8–10. The wavelength λ2 illustrated
in Figure 158 is the internal wavelength generated by QPM OPO NFM device 74
(Ex. 1010, 18:46–63), whereas in Figure 16, the internally generated wavelength
by NFM device 84, when it is functioning as a QPM OPO device, is not shown.
Opp. 9 (asserting that the internally generated wavelength by NFM device 84 is
λ4); Ex. 1017 ¶¶ 5–6. Wavelength λ2 in Figure 16 is the input wavelength to NFM
device 84. See Opp. 9. In other words, BAE’s proposed combination does not
bodily incorporate the embodiment of Figure 15 into Figure 16 (see Ex. 2010 ¶ 6)
such that the reference to λ2 in each embodiment refers to the same wavelength.
Cheetah further contends that even if the proposed combination could work,
it would be “highly inefficient because λ2 is generated but put to no gainful use.”
PO Reply 5 (citing Ex. 2010 ¶ 9). We likewise are not persuaded by this

8 BAE refers to Figure 15 of Sanders to show a NFM device that functions as a
QPM OPO device. Pet. Reply 3–4 n.1; Opp. 9–10.
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argument. A combination of teachings that results in an inefficient system still
may render a claim obvious, provided there was a reason for a person of ordinary
skill in the art to have made the combination. See In re Farrenkopf, 713 F.2d 714,
716-17 (Fed. Cir. 1983) (where a prior art reference taught the addition of
inhibitors as the most convenient, but costliest, solution to a particular problem, the
court held that the additional expense would not have discouraged one of ordinary
skill in the art from seeking the convenience expected therefrom). As discussed
above, we are not persuaded that wavelength λ2, as illustrated in Figure 16, has no
gainful use, and BAE has put forth a sufficient reason to combine the teachings of
Sanders and Lees, as explained above. Lastly, Cheetah contends that BAE’s
proposed combination does not render the substitute claims obvious because
wavelength λ2, which Cheetah equates with the recited “second optical
wavelength,” is discarded. PO Reply 5. As stated above, we are not persuaded by
this argument.
Based on the foregoing discussion, Cheetah has not met its burden to
demonstrate that claims 21 and 24 would have been unpatentable over the
combination of Sanders and Lees.
Patentability of Substitute Claims 22 and 25
Cheetah proposes substituting claim 1 with claim 22 if substitute claim 21 is
found unpatentable and substituting claim 13 with claim 25 if substitute 24 is
found unpatentable. Mot. 2. Cheetah acknowledges that it has provided two
substitute claims for original claim 1 and two substitute claims for original claim
13. Id. at 12. Rule 42.121(a)(3) states the presumption that only one substitute
claim is necessary to replace a challenged claim, and states the presumption may
be rebutted by a demonstration of need. See Idle Free Sys. v. Bergstrom, Inc.,
IPR2012-00027, Paper 26 at 2 (June 11, 2013). Cheetah argues that there is need
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for more than one substitute claim because the Board’s one-year timeline will not
be affected given the structure of the substitution contingencies; it has one
opportunity, barring authorization to file an additional motion to amend, “to get it
right and there is currently no meaningful guidance as to the metes and bounds of
the ‘demonstration of need’”; and, it has provided the Board with “key portions of
Petitioner’s prior art and explanation as to why the art does not read on the
substitute claims.” Mot. 12–14; PO Reply 2–3.
We agree with BAE that Cheetah has not demonstrated a need for proposing
more than one substitute claim for each of claims 1 and 13. See Opp. 2–3.
Substitute claim 22 is identical to substitute claim 21, except for the additional
recital of “wherein the Q-switcher produces an output signal having a pulse width
in the range of two (2) nanoseconds to one hundred (100) milliseconds.” Mot. 3–4.
Cheetah proposes a similar scheme to replace original claim 13. Id. at 5–6.
Cheetah, however, has not demonstrated the need for proposing narrower
substitute claims than the ones we already have considered.
In addition, in order to justify more than one substitute claim for each
challenged claim, “a patent owner has to show a special need to justify more than
one substitute claim for each challenged claim. In such situations, the patent
owner needs to show patentable distinction of the additional substitute claim over
all other substitute claims for the same challenged claim.” See Idle Free, Paper 26
at 5, 8–9. With respect to the new limitation of claims 22 and 25, Cheetah states
that “[t]he prior art does not read on the Q-switcher output pulse width because it
does not read on the Q-switcher itself.” Mot. 12. In its Reply, Cheetah states that
“in the manner that the limitations would be read into the claims, the distinction is
facially clear without explanation.” PO Reply 3. Cheetah’s conclusory statements
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have not persuaded us of a patentable distinction of substitute claims 22 and 25
over substitute claims 21 and 24, respectively. See Opp. 4.
Cheetah also was required to discuss the “significance and usefulness” of the
added features in a proposed substitute claim “from the perspective of one with
ordinary skill in the art.” See Idle Free, Paper 26 at 7. This Cheetah failed to do
with respect to claims 22 and 25. Therefore, we determine that Cheetah has not
met its burden to demonstrate that claims 22 and 25 are patentable.
Patentability of Substitute Claims 23 and 26
Cheetah proposes substituting claim 4 with substitute claim 23 if claims 21
and 4 are both found unpatentable, and substituting claim 15 with substitute claim
26 if claims 24 and 15 are found unpatentable. Mot. 2. Claims 23 and 26 recite
the new limitation “and wherein the Q-switcher produces an output signal having a
pulse width in the range of two (2) nanoseconds to one hundred (100)
milliseconds.” Id. at 4–7. If Cheetah’s motion is granted with respect to
substitute claims 23 and 26, substitute claims 23 and 26 would depend from
original claims 1 and 13, respectively. Original claims 1 and 13, however, do not
recite a Q-switcher. Thus, there would be no antecedent basis for “the Q switcher”
recited in claims 23 and 26, and thus, the dependency of those claims is improper.
Moreover, as discussed above with respect to substitute claims 22 and 25, Cheetah
does not explain why the pulse width of the Q-switcher affects the patentability of
substitute claims 23 and 26, or why there is a patentable distinction between
substitute claim 23 and substitute claim 21, or between substitute claim 26 and
substitute claim 24. See Idle Free, Paper 26 at 9–10. We, therefore, determine that
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Cheetah has not met its burden to demonstrate that claims 23 and 26 are
patentable.9
Accordingly, we deny Cheetah’s motion to amend.

E. BAE’s Motion for Observation
BAE filed a motion for observation regarding Dr. Ippen’s testimony on
cross-examination. Paper 38. We have considered BAE’s observations and
Cheetah’s responses. See Papers 38, 41.

III. ORDER
BAE has demonstrated, by a preponderance of the evidence, that (1) claims
1, 4, 13, 15, 17, and 19 are unpatentable as anticipated by Sanders under 35 U.S.C.
§ 102(b); and (2) claim 14 is unpatentable as obvious over Sanders under 35
U.S.C. § 103(a).
In consideration of the foregoing, it is hereby:
ORDERED that claims 1, 4, 13–15, 17, and 19 of the ’673 patent have been
shown to be unpatentable; and
FURTHER ORDERED that Cheetah’s Motion to Amend is denied.

9 We need not consider any other arguments raised by BAE in its opposition to
Cheetah’s motion to amend, given that we deny Cheetah’s motion for the reasons
explained herein.
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Petitioner:

Jeffrey Sanok
Suzanne Walts
Crowell & Moring LLP
JSanok@Crowell.com
SWalts@Crowell.com

Patent Owner:

Richard Krukar
Kermit Lopez
Ortiz & Lopez, PLLC
krukar@olpatentlaw.com
klopez@olpatentlaw.com