Mark Phillips

Patent Trials and Appeals Board

Sep 24, 2021

2020006797 (P.T.A.B. Sep. 24, 2021)

UNITED STATES PATENT AND TRADEMARK OFFICE
UNITED STATES DEPARTMENT OF COMMERCE
United States Patent and Trademark Office
Address: COMMISSIONER FOR PATENTS
P.O. Box 1450
Alexandria, Virginia 22313-1450
www.uspto.gov
APPLICATION NO. FILING DATE FIRST NAMED INVENTOR ATTORNEY DOCKET NO. CONFIRMATION NO.
15/782,659 10/12/2017 Mark C. Phillips 23-99622-01 8826
32215 7590 09/24/2021
KLARQUIST SPARKMAN, LLP (Battelle)
121 SW SALMON STREET, SUITE 1600
ONE WORLD TRADE CENTER
PORTLAND, OR 97204
EXAMINER
HAGAN, SEAN P
ART UNIT PAPER NUMBER
2828
NOTIFICATION DATE DELIVERY MODE
09/24/2021 ELECTRONIC
Please find below and/or attached an Office communication concerning this application or proceeding.
The time period for reply, if any, is set in the attached communication.
Notice of the Office communication was sent electronically on above-indicated "Notification Date" to the
following e-mail address(es):
docketing@klarquist.com
erin.vaughn@klarquist.com
PTOL-90A (Rev. 04/07)
UNITED STATES PATENT AND TRADEMARK OFFICE
BEFORE THE PATENT TRIAL AND APPEAL BOARD
Ex parte MARK C. PHILLIPS
Appeal 2020-006797
Application 15/782,659
Technology Center 2800
Before JEFFREY T. SMITH, LINDA M. GAUDETTE, and
JAMES C. HOUSEL, Administrative Patent Judges.

HOUSEL, Administrative Patent Judge.
DECISION ON APPEAL
STATEMENT OF THE CASE
Pursuant to 35 U.S.C. § 134(a), Appellant1 appeals from the
Examiner’s decision to reject claims 1–23 under 35 U.S.C. § 103 as
unpatentable over Zhang (US 2001/0040910 A1, pub. Nov. 15, 2001) in
view of Pang (US 8,514,898 B1, iss. Aug. 20, 2013). We have jurisdiction
under 35 U.S.C. § 6(b).
We AFFIRM.

1 We use the word “Appellant” to refer to “applicant” as defined in 37
C.F.R. § 1.42. Appellant identifies Battelle Memorial Institute as the real
party in interest. Appeal Brief (“Appeal Br.”) filed December 30, 2019, at 3.
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CLAIMED SUBJECT MATTER
The invention recited in the claims on appeal relates to tunable
external cavity lasers. Specification (“Spec.”) filed October 12, 2017, ¶ 5.2
Appellant discloses apparatus, systems, and methods for scanning the
wavelength of an external cavity laser using synchronized angular motion of
two mirrors, where the first mirror or reflector is rotatable about a first axis
and a second mirror or reflector is rotatable about a second axis. Id. The first
mirror is situated to receive an intracavity beam of the laser from a
diffraction grating and the second mirror is situated to retro-reflect the beam
received from the first mirror back to the first mirror and to the diffraction
grating. Id. Appellant discloses that the system additionally includes at least
one processor and one or more computer-readable storage media including
instructions that, when executed by the processor, cause the mirrors to rotate
so as to vary an external cavity length and external cavity output beam
wavelength. Id. ¶ 6.
Claim 1, reproduced below from the Claims Appendix to the Appeal
Brief, is illustrative of the claimed subject matter:
1. An apparatus, comprising:
a first reflector rotatable about a first axis and situated to
receive an intracavity laser beam of an external cavity laser from
a diffraction grating and to direct the intracavity laser beam along
a first direction; and
a second reflector rotatable about a second axis and
situated to retro-reflect the intracavity laser beam received from

2 This Decision also cites to the Final Office Action (“Final Act.”) dated
June 13, 2019, the Examiner’s Answer (“Ans.”) dated April 28, 2020, and
the Reply Brief (“Reply Br.”) filed June 29, 2020.
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the first reflector back to the first reflector and to the diffraction
grating.
Claim 18 recites a system comprising a plurality of reflectors, at least
one processor, and at least one computer-readable storage media, wherein
the reflectors are situated to rotate about respective axes in relation to a
diffraction grating and laser source.
Claim 19 recites a method of using the apparatus, wherein a first
portion of a laser beam forms an output beam of the laser and a second
portion of the beam is received by the mirrors, respectively.
Claim 22 recites a method of using an apparatus substantially as
recited in claim 1.
OPINION
We review the appealed rejection for error based upon the issues
Appellant identifies, and in light of the arguments and evidence produced
thereon. Ex parte Frye, 94 USPQ2d 1072, 1075 (BPAI 2010) (precedential),
cited with approval in In re Jung, 637 F.3d 1356, 1365 (Fed. Cir. 2011)
(“[I]t has long been the Board’s practice to require an applicant to identify
the alleged error in the examiner’s rejections.”). After considering the record
before us, we are not persuaded of reversible error in the pending rejection.
Accordingly, we affirm the Examiner’s obviousness rejection for the
findings, reasoning, and conclusions aptly set forth in the Final Office
Action and the Examiner’s Answer, which we adopt as our own as if
repeated here. We add the following primarily for emphasis.
The Examiner finds that Zhang discloses an apparatus comprising first
reflector 1422 situated to receive intracavity laser beam of external cavity
laser 1408 from diffraction grating 1410 and second reflector 1412 rotatable
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about a second axis and situated to retro-reflect the intracavity laser beam
back to first reflector 1422 and diffraction grating 1410. Final Act. 6. The
Examiner acknowledges that Zhang fails to disclose that first reflector 1422
is rotatable about a first axis, but finds that Pang teaches a pair of reflectors,
each of which is rotatable about respective axes. Id. The Examiner concludes
that it would have been obvious to have modified Zhang’s apparatus such
that both first reflector 1422 and second reflector 1412 are rotatable about
respective axes such that the laser is tuned by simultaneous alteration of
reflection angle and translation to exhibit a particular cavity length given a
tuned wavelength. Id. at 7. The Examiner finds that an ordinary artisan
would have been motivated to make such a modification to Zhang because
“allowing the center of rotation of [reflectors 1422, 1412] to be adjusted
relative to one another . . . [allows] for a weight balance that allows for
higher speed tuning.” Id.
Appellant argues that modifying Zhang in view of Pang as proposed
by the Examiner would change Zhang’s principle of operation. Appeal Br. 5.
Appellant asserts that “Zhang’s operational principle is rotation about a
carefully chosen pivot 1402.” Id.; see also Reply Br. 4. Appellant further
asserts that Pang’s manner of rotation produces a translation of its beam
normally incident through the fixed aperture 82 at the fixed retroreflective
mirror 66 to select Pang’s wavelength. Appeal Br. 6. Appellant contends that
modifying Zhang by moving both reflectors 1412, 1422 so as to achieve the
same overall effect of rotation and translation as in Pang “would uncouple
Zhang’s intracavity feedback to the gain medium 1408 and reflector 1406
and [Zhang’s] device would stop working and would therefore be rendered
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unsatisfactory for its intended purpose.” Id. at 6–7 (reproducing annotated
Fig. 4 of Pang and annotated Fig. 14 of Zhang).
Appellant’s arguments are not persuasive of reversible error. We first
note that Appellant’s arguments present two related, but distinct legal
principles. The first legal principle is that there is no suggestion or
motivation to make a proposed modification if doing so would render the
prior art invention being modified unsatisfactory for its intended purpose. In
re Gordon, 733 F.2d 900, 902 (Fed. Cir. 1984); see also DePuy Spine, Inc. v.
Medtronic Sofamor Danek, Inc., 567 F.3d 1314, 1326 (Fed. Cir. 2009)
(“[T]he ‘predictable result’ discussed in [KSR] refers not only to the
expectation that prior art elements are capable of being physically combined,
but also that the combination would have worked for its intended purpose.”).
The second legal principle is that combinations of prior art that change the
“basic principles under which the [prior art] was designed to operate” may
not support a conclusion of obviousness. In re Ratti, 270 F.2d 810, 813
(CCPA 1959). Because these two legal principles are related, it is possible
that a proposed combination would not have been obvious because the
proposed modification would render a prior art device inoperable such that
operating according to its intended operational principle would be
impossible. This latter situation appears to be what Appellant is arguing
here.
In order to address Appellant’s argument, we first look to determine
Zhang’s principle of operation and then assess whether the proposed
modification is a change in this principle of operation. If Zhang’s principle
of operation is changed, the proposed combination may not support the
Examiner’s obviousness conclusion. Ratti, 270 F.2d at 813. On the other
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hand, if the proposed modification allows operation of Zhang “on the same
principles as before,” Ratti is inapplicable. In re Umbarger, 407 F.2d 425,
430–431 (CCPA 1969); see also In re Mouttet, 686 F.3d 1322, 1332 (Fed.
Cir. 2012) (difference in circuitry—electrical versus optical—does not affect
the overall principle of operation of a programmable arithmetic processor).
In determining Zhang’s “principle of operation,” we may rely on Zhang’s
description of its contribution to the art. Plas-Pak Indus., Inc. v. Sulzer
Mixpac AG, 600 Fed. Appx. 755, 758 (Fed. Cir. 2015).
The Examiner finds that Zhang’s operational principle is to provide
mode-hop-free tuning of a grating-tuned external cavity laser by keeping the
cavity length L(λ) a constant integer multiple of the mode number over the
entire tuning range as set forth by the equation L(λ)=N*λ/2, where N is the
mode number. Ans. 8. Zhang, like Appellant, teaches that a tunable laser
beam can be produced by a reflector in a Littman-type configuration which
provides a foundation for producing tunable narrow-bandwidth lasers,
including a mode-hop-free Littman cavity laser system with broad-range
tuning capabilities. Compare Zhang ¶¶ 4, 9, with Spec. ¶¶ 4, 28. Zhang
further discloses that the output of prior grating-tuned, external cavity laser
systems generally consisted of two spectral components: (1) a laser beam;
and (2) undesirable background light radiation comprising Source
Spontaneous Emission (“SSE”) and Amplified Spontaneous Emission
(“ASE”) light radiation. Zhang ¶ 13. Zhang discloses that it is the second
spectral component which the invention guides to a physical filtering device
by a guiding unit to be filtered out. Id. ¶¶ 13, 14, 21.
Although Zhang discloses embodiments in which a feedback path is
defined by a single movable reflector without a guiding reflector, such as in
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Figure 3, Zhang teaches an alternative arrangement in which the filtering is
performed using a pair of reflectors, one of which is movable, such as in
Figure 14. Id. ¶¶ 123–125. Zhang further teaches that, for mode-hop-free
laser tuning while the rotatable reflector moves, the total length L(λ) of the
laser cavity must stay constant over the whole range of tunable wavelengths
and must be an integer multiple of the mode number, L(λ)=Nλ/2. Id. ¶ 128.
As the Examiner finds (Ans. 8), this relationship does not depend on a single
carefully selected pivot point, as Zhang teaches two embodiments having
different pivot points. Zhang Figs. 1, 15.
These disclosures do not support Appellant’s assertion that Zhang’s
operational principle is rotation about a carefully chosen pivot 1402. Instead,
these disclosures support the Examiner’s finding that Zhang’s operational
principle is to provide mode-hop-free tuning of a grating-tuned external
cavity laser by keeping the cavity length L(λ) a constant integer multiple of
the mode number over the entire tuning range as set forth by the equation
L(λ)=N*λ/2.
We next evaluate whether the Examiner’s proposed modification to
Zhang changes its principle of operation. The Examiner finds that Pang also
teaches a wavelength-tunable external cavity laser with two embodiments: 1)
a single moving reflector as shown in Figure 1; and 2) two moving reflectors
as shown in Figure 2. Ans. 5. The Examiner finds that Pang teaches, in the
first embodiment that
light is oscillated between mirrors 34 and 36 with the wavelength
selected due to the movement of mirror 46 such that light of a
given wavelength exiting prism 42 at a wavelength dependent
angle is reflected through stop 50 so as to select the operational
wavelength as discussed in lines 4 through 27 of column 5 of
Pang. As can be seen in Figure 2, the movement of mirror 46 also
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alters the overall length of the beam path and this alteration is of
concern to Pang due to how it affects cavity dispersion as
discussed in lines 27 through 33 of column 5.
Id. The Examiner further finds that Pang’s second embodiment
is an alternative to the arrangement of Figure 1 in which mirrors
78 and 80 are moved so as to accomplish the same change in
angle and cavity length as is achieved by mirror 46 of Figure 1.
Pang discloses in lines 20 through 31 of column 7 that this
provides improved tuning speed through consideration of weight
balance.
Id. Thus, as the Examiner determines (id.), because Pang teaches that a two
moving mirror system may be arranged to mimic a one moving mirror
system to achieve that same angle and cavity length changes, modifying
Zhang to employ two moving mirrors while maintaining the cavity length
relationship L(λ) would not change Zhang’s principle of operation. Further,
this conclusion is further reinforced by the fact that modifying Zhang to
permit both reflectors to rotate would not change Zhang’s operational
principle because, again, Zhang, like Appellant, teaches that tunable laser
beam can be produced by a reflector in a Littman-type configuration which
provides a foundation for producing tunable narrow-bandwidth lasers,
including a mode-hop-free Littman cavity laser system with broad-range
tuning capabilities.
We turn next to Appellant’s argument that modifying Zhang by
moving both reflectors 1412, 1422 so as to achieve the same overall effect of
rotation and translation as in Pang would render Zhang inoperable for it
intended purpose. We disagree. As the Examiner aptly explains
[i]n the context of Pang, it is understood that the improved tuning
speed identified by Pang is a result of the mirrors being physical
objects that must be moved as explained in lines 16 through 25
of column 6 and that larger physical movement results in slower
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tuning as noted in lines 1 through 4 of column 6. From this, it is
understood that improvements in speed due to improved weight
balance as discussed in lines 20 through 31 of column 7 also
result from considerations of physical movement of the
reflectors. In this context, the arrangement of Figure 5 may be
compared to the arrangements of Figures 3A and 3B and
understood to indicate that the motion of two moving mirrors
may be selected to mimic an angle and cavity length change
otherwise achieved in a single moving mirror while reducing the
physical movement necessary to produce the required change in
angle and cavity length. Since this improvement in tuning speed
is achieved through improved weight balance of the system and
through modifications that move the axis of rotation closer to the
reflectors, it is understood that these teachings of Pang may be
implemented in systems other than systems that require the exact
movement employed by Pang. In the case of Zhang, it is
determined that these teachings of Pang may be implemented in
a device of Zhang by modeling rotation of reflector 1422 with a
concurrent movement of reflector 1412 such that the relationship
required by p. [0128] of Zhang is preserved in all cases and
selecting the coordinated motion of reflectors 1422 and 1412 that
produce the most desirable weight balance.
Ans. 10–11. Appellant has not demonstrated that this modification would
uncouple Zhang’s intracavity feedback to the gain medium 1408 and
reflector 1406 so as to render Zhang’s device inoperable. To the contrary, as
the Examiner explains, the modification to Zhang’s device would preserve
that relationship L(λ), while providing the benefits of faster tuning with the
most desirable weight balance.
Appellant next argues that an ordinary artisan would not be motivated
to modify Zhang as the Examiner proposes because Zhang already solved
the problem of wavelength locking without mode hopping using a
geometrically static setup and a single pivot arrangement. Appeal Br. 7–8.
Appellant also contends that the Examiner’s reasoning for modifying Zhang
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is unsupported by Pang because Pang does not explain what “weight
balance” is or how it is applied other than that it can further increase
wavelength tuning speed. Id. at 8; see also Reply Br. 2. Appellant also
asserts that Pang fails to disclose that “weight balance” is the result of
allowing the two mirrors to rotate. Appeal Br. 8. Appellant urges that the
only successful introduction of rotatable first and second reflectors is in
Appellant’s disclosure, and that the Examiner’s proposed combination of
Zhang and Pang “has the hallmarks of impermissible hindsight reliance.” Id.
at 8–9. Moreover, Appellant asserts that both Pang’s embodiments of
Figures 1 and 4 have the benefit of high speed tuning and weight balance
relied on by the Examiner in support of the obviousness conclusion. Reply
Br. 2.
Appellant’s arguments are unpersuasive of reversible error. Merely
because Zhang provides a solution to a problem does not mean that
improvements to that solution, though suggested in the prior art, could not
have been obvious to an ordinary artisan at the time of the invention, i.e.,
does not mean the ordinary artisan would not have sought to further improve
upon the solution. As the Examiner explains (Ans. 5), “Pang teaches that a
single moving reflector, as in Figure 1 of Pang, may be replaced with two
moving reflectors, as in Figure 4 of Pang, so as to alter the weight balance of
the moving reflectors and thereby allow tuning speed to be increased.” In
other words, though Zhang provides a solution to mode-hop-free tuning, an
ordinary artisan would have been motivated to further improve Zhang’s
solution using Pang’s teaching that using two moving reflectors would
increase the tuning speed. Further, contrary to Appellant’s assertion, Pang
specifically attributes higher speed tuning (and other advantages) to the
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Figure 4 embodiment. Pang 7:20–31. This motivation alone is sufficient to
support the Examiner’s proposed modification of Zhang. Pang’s reference to
“weight balance” merely provides an additional benefit in terms of tuning
speed and thus any ambiguity in Pang’s disclosure regarding “weight
balance” in itself would not establish error in the Examiner’s obviousness
conclusion.3 Moreover, because this motivation comes from the references
themselves, the obviousness conclusion is not based on impermissible
hindsight.
Appellant next argues that, regarding dependent claims 3, 21, and 23,
that Zhang’s mode-hop-free operation is confusing and may not be readily
understood by one of ordinary skill in the art. Appeal Br. 9. In this regard,
Appellant asserts that the rejection relies on maintaining Zhang’s cavity
length constant with respect to wavelength by changing while the
wavelength is changed. Id. Appellant contends, however, that Zhang states
that “M1-G-M2-M3 must stay constant over the whole range of tunable
wavelengths.” Id. According to Appellant, “even if Zhang discloses mode-
hop-free operation using its single pivot configuration, there is no teaching
or suggestion anywhere that would lead a person of ordinary skill to produce
mode-hop-free operation over a predetermined range with two rotatable
reflectors, as [Appellant] has claimed in dependent claims 3, 21, and 23.” Id.
at 9–10.

3 We also credit the Examiner’s explanation of how an ordinary artisan
would have understood Pang’s reference to “weight balance,” given Pang’s
discussion of both the physical motion of the mirrors and the mirror mass.
See Ans. 13–14.
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Appellant’s argument regarding dependent claims 3, 21, and 23 is not
persuasive of reversible error. As the Examiner notes (Ans. 17–18), Zhang
provides a mathematical equation, L(λ)=N*λ/2, to explain the relationship
between cavity length and wavelength. Zhang ¶ 128. Zhang also explains
that the cavity length must stay constant over the range of tunable
wavelengths and is an integer multiple of the mode number. Id. Given
Zhang’s mathematical relationship, we are not persuaded that Zhang’s
disclosure is confusing to those of ordinary skill in the art. As to Appellant’s
assertion that there is no teaching or suggestion in Zhang that would lead an
ordinary artisan to produce mode-hop-free operation over a predetermined
range with two rotatable reflectors as set forth in dependent claims 3, 21, and
23, this assertion is merely conclusory and fails to address the basis for
modifying Zhang in view of Pang.
Accordingly, we sustain the Examiner’s obviousness rejection of
claims 1–23.
CONCLUSION
Upon consideration of the record and for the reasons set forth above
and in the Final Office Action and the Examiner’s Answer, the Examiner’s
decision to reject claims 1–23 under 35 U.S.C. § 103 as unpatentable over
Zhang in view of Pang is affirmed.
DECISION SUMMARY
In summary:
Claims
Rejected
35 U.S.C.
§
Reference(s)/Basis Affirmed Reversed
1–23 103 Zhang, Pang 1–23

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TIME PERIOD FOR RESPONSE
No time period for taking any subsequent action in connection with
this appeal may be extended under 37 C.F.R. § 1.136(a). See 37 C.F.R.
§ 1.136(a)(1)(iv).
AFFIRMED