Ex Parte Velthaus et al

Patent Trial and Appeal Board

Sep 26, 2018

14127927 (P.T.A.B. Sep. 26, 2018)

UNITED STA TES p A TENT AND TRADEMARK OFFICE
APPLICATION NO. FILING DATE
14/127,927 03/26/2014
97149 7590 09/28/2018
Maschoff Brennan
1389 Center Drive, Suite 300
Park City, UT 84098
FIRST NAMED INVENTOR
Karl-Otto Velthaus
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
ATTORNEY DOCKET NO. CONFIRMATION NO.
Ml023.10059US01 4360
EXAMINER
TAVLYKAEV, ROBERT FUATOVICH
ART UNIT PAPER NUMBER
2883
NOTIFICATION DATE DELIVERY MODE
09/28/2018 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):
docket@mabr.com
info@mabr.com
PTOL-90A (Rev. 04/07)
UNITED STATES PATENT AND TRADEMARK OFFICE
BEFORE THE PATENT TRIAL AND APPEAL BOARD
Ex parte KARL-OTTO VEL THAUS, DETLEF HOFFMANN, and
MARKO GRUNER
Appeal2017-005793
Application 14/127,927
Technology Center 2800
Before CATHERINE Q. TIMM, WESLEY B. DERRICK, and
MERRELL C. CASHION, JR., Administrative Patent Judges.
DERRICK, Administrative Patent Judge.
DECISION ON APPEAL 1
Appellants2 seek review under 35 U.S.C. § 134 from the Examiner's
decision rejecting claims 1--4 and 11-21 under 35 U.S.C. § 103(a) over
1 This decision cites to the following: the Specification filed December 19,
2013 ("Spec."), the Final Office Action dated July 27, 2015 ("Final Act."),
the Advisory Action dated December 9, 2015 ("Adv. Act."), the Appeal
Brief filed April 25, 2016 ("App. Br."), the Examiner's Answer dated
December 19, 2016 ("Ans."), and the Reply Brief filed February 21, 2017
("Reply Br.").
2 Appellants identify FRAUNHOFER-GESELLSCHAFT ZUR
FORDERUNG DER ANGEWANDTEN FORSCHUNG E.V. as the real
party in interest. App. Br. 4.
Appeal2017-005793
Application 14/127,927
Morl3 in view ofLi4 and Caniggia. 5 We have jurisdiction under 35 U.S.C.
§ 6.
We AFFIRM-IN-PART.
STATEMENT OF CASE
Appellants' invention relates to an electro-optic Mach-Zehnder
modulator, with a first optical waveguide and a second optical waveguide
forming a first arm and a second arm, respectively, of the Mach-Zehnder
modulator. Spec., Abstract. Claims 1, 18, 19, and 21 are independent.
Claims 1 and 19 are directed to electro-optic Mach-Zehnder modulators.
Claims 18 and 21 are directed to methods of fabricating the modulators
recited in claims 1 and 19, respectively.
Claims 1 and 19 are illustrative:
1. An electro-optic Mach-Zehnder modulator, comprising
- a first optical waveguide forming a first arm of the
Mach-Zehnder modulator;
- a second optical waveguide forming a second arm of
the Mach-Zehnder modulator,
wherein
- the first and/or the second optical waveguide comprises
a plurality of capacitive segments spaced apart from one
another, the capacitive segments each forming an electrical
capacitor; and
3 Morl et al., Traveling Wave Electrodes for 50 GHz Operation of Opto-
Electronic Devices Based on InP, 11th Int'l Conf. on Indium Phosphide and
Related Materials, paper WeAl-3, pp. 385-388, May 16-20, 1999.
4 Li et al., Analysis of Segmented Traveling-Wave Optical Modulators, J.
Lightwave Tech. 22(7), 1789--1796, July 7, 2004.
5 Caniggia, Signal Integrity and Radiated Emission of High-Speed Digital
Systems, John Wiley & Sons, 2008.
2
Appeal2017-005793
Application 14/127,927
- a travelling wave electrode arrangement for applying a
voltage across the first and/or the second optical waveguide, the
travelling wave electrode arrangement comprising
- a plurality of waveguide electrodes arranged on
the capacitive segments;
- at least one electrical line extending at least
partially along a part of the first and/or the second optical
waveguide, the electrical line being arranged in a
distance from the waveguide electrodes; and
- a plurality of connecting arrangements, wherein a
connecting arrangement is assigned to each of the
waveguide electrodes, wherein the connecting
arrangements each comprise at least two connecting
structures spaced apart from one another wherein the
waveguide electrodes each are electrically connected to
the electrical line via the assigned two connecting
structures the connecting arrangements assigned to one of
the waveguide electrodes are connected to a straight
portion of the electrical line.
19. An electro-optic Mach-Zehnder modulator, comprising
a first optical waveguide forming a first arm of the Mach-
Zehnder modulator;
a second optical waveguide forming a second arm of the
Mach-Zehnder modulator, wherein
the first and/or the second optical waveguide comprises a
plurality of capacitative segments spaced apart from one
another, the capacitive segments each forming an electrical
capacitor; and
a travelling wave electrode arrangement for applying a
voltage across the first and/or the second optical waveguide, the
travelling wave electrode arrangement comprising
a plurality of waveguide electrodes arranged on the
capacitive segments
at least one electrical line extending at least
partially along a part of the first and/or the second optical
3
Appeal2017-005793
Application 14/127,927
waveguide, the electrical line being arranged in a
distance from the waveguide electrodes; and
a plurality of connecting arrangements, wherein a
connecting arrangements is assigned to each of the
waveguide electrodes, the connecting arrangements each
comprise a single wide connecting structure having a
width that equals the length of the assigned waveguide
electrode, wherein the width of the wide connecting
structure and the length of the waveguide electrode are
measured along the first and/ or the second optical
waveguide, and wherein the waveguide electrodes each
are electrically connected to the electrical line via the
assigned single wide connecting structure, wherein the
plurality of wide connecting structures is formed by a
continuous contact structure extending along the first
and/or the second optical waveguide, wherein the wide
connecting structures are formed by portions of the
continuous contact structure.
App. Br. 14, 17 ( emphasis added).
DISCUSSION
Upon consideration of the evidence and opposing contentions of
Appellants and the Examiner, we are not persuaded that the Examiner erred
harmfully in rejecting claims 1--4 and 11-18 for obviousness over the cited
prior art, but are persuaded of reversible error as to claims 19-21.
Morl relates to the design, fabrication and performance of electro-
optic switches based on a Mach-Zehnder interferometer with traveling wave
electrodes. Morl, Abstract. The Examiner relies on Morl for disclosing an
electro-optic modulator comprising a plurality of T-shaped connecting
arrangements connected to a corresponding electrical line (to which an RF
source is connected). Ans. 2 ( citing Morl, Fig. 1 ); see also Final Act. 5---6
(citing Morl 385, 386-87 (Section II), Figs. 1-2). The Examiner finds Morl
4
Appeal2017-005793
Application 14/127,927
to teach "that the benefit of a faster modulation speed (broader modulation
bandwidth) can be achieved by using T-shaped connecting arrangements
with a shorter length l," where the structure of a connecting arrangement is
highlighted by a magnified view of a portion of Morl' s Figure 1:
e
w
Ans. 2 (citing Morl 387 (Section III), Figs 1, 4); see also Final Act. 7 ("Morl
... determines (lower graph in Fig. 4; Section III) that a broader frequency
response (wider bandwidth of operation) can be achieved by using a finer
segmentation"). The Examiner determines that the
modulator of Morl meets all of the limitations of claims 1, 18,
19, and 21 except that each T-shaped connecting arrangement
has a width w of the vertical leg ( connecting structure) that
appears to be much shorter than the length l ( w< < l) and Morl
does not teach that the benefit of a faster modulation speed can
also be achieved by widening w ... either in a continuous
electrode width (single wide leg/connecting structure as in Fig.
4 of the instant application) or a discontinuous arrangement[]
(with 2 or more legs/connecting structures producing a II-
shaped connecting arrangement as in Figs. 1 and 3 of the
instant application).
Ans. 2-3; see also Final Act. 5-7.
5
Appeal2017-005793
Application 14/127,927
Li also relates to the design and analysis of segmented traveling-wave
optical modulators. Li, Abstract. The Examiner relies on Li for its
disclosure of "an electro-optic modulator having a structure similar to that of
Morl and comprising a plurality of T-shaped connecting arrangements."
Ans. 3; see also Final Act. 8. The Examiner finds
Li [also] desires the same benefit of a faster modulation speed
(broad modulation bandwidth) and teaches that it can be
achieved by using T -shaped connecting arrangements with a
shorter length l ( as shown in Fig. 4 and corresponding to the
method of Morl) AND/OR by reducing the inductance of the
connecting arrangements (Fig. 5).
Ans. 3 ( citing Li, Figs. 4, 5). The Examiner also relies on Li for expressly
teaching "that the inductance can be controlled by adjusting the bridge
width (the width of the vertical leg), with lower inductances resulting in a
broader bandwidth (beneficial)." Id. ( citing Li 1793, 1st complete
paragraph).
As to reducing inductances, the Examiner maintains that "the fact that
wider conductors/electrodes have lower inductances is common (textbook)
knowledge in the art" and cites Caniggia for this proposition. Id. The
Examiner relies on Caniggia for providing a well-known expression for the
inductance of single wiring at a high frequency and finds it to "clearly
show[] that such inductance decreases with the width/radius of the wiring r w
(as ln(2llrw)." Id. at 3--4 (citing Caniggia 482); see also Final Act. 9. The
Examiner also relies on Caniggia as disclosing the "common knowledge that
electrode inductance can be decreased by connecting two bridges in parallel
to each other" as this corresponds to "[ t ]wo parallel wires with currents in
the same direction." Ans. 4 (citing Caniggia 482); see also Final Act. 9--10.
6
Appeal2017-005793
Application 14/127,927
In sum, the Examiner has determined: (i) that the number of
segments, inversely related to length l, is a result-effective variable for
modulation speed; (ii) that the inductance of connecting arrangements is a
(negatively correlated) result-effective variable for modulation speed; and
(iii) that the width w, either in a single leg forming a T-shaped structure or in
two or more legs forming a II-shaped structure, is a (negatively correlated)
result-effective variable for inductance.
The Examiner concludes, accordingly, that one of ordinary skill in the
art at the time of the invention armed with the cited prior art would have
been led to the claimed subject matter through no more than the effort of a
routineer to discover the optimum or workable ranges. Ans. 6, 7. Moreover,
the Examiner determines that an obvious-to-try rationale also applies
because of the limited number of well-known alternative solutions described
by Caniggia for reducing electrode inductance with a well-defined benefit of
broader modulation bandwidth and faster modulation speed with a
reasonable expectation of success. Id.
As to claim 1, Appellants contend that the Examiner erred in
determining the wavelength in Marl's device. App. Br. 9--10. Appellants
also contend that Marl's electrodes cannot be considered lumped elements
because they are too long. Id. at 10-11. Appellants further contend that
because of the electrodes' excessive length relative to the wavelength, as it is
correctly calculated, "a skilled person would have to assume that an
additional current path is introduced when using two instead of a single
contact bridge ... such that a dramatic change of the overall electrical
behavior would have been expected." Id. at 9--10. Appellants further
contend that, "since the TWE electrodes [of Marl] are not lumped elements,
7
Appeal2017-005793
Application 14/127,927
their electrical properties (such as their impedance) are very sensitive to
design modifications." Id. at 11. Appellants also argue that there is no
incentive in Morl to use shorter electrodes because the number of required
interfaces "would cause unacceptable high optical losses." Id.
Appellants' arguments are not persuasive of harmful error because it
fails to address the Examiner's reasoning grounded on the number of
segments and electrode length being result-effective variables, which would
reasonably lead the skilled artisan to shorter lengths (more segmentation) in
order to obtain broader modulation bandwidth and faster modulation speed.
As to Morl providing no incentive to use shorter electrodes because of
unacceptable optical losses, the argument fails to address the combination
set forth by the Examiner, including Li for its teaching that reducing
inductance also provides the same desired benefits alone, or in combination
with greater segmentation. In re Keller, 642 F.2d 413,426 (CCPA 1981)
("[O]ne cannot show non-obviousness by attacking references individually
where, as here, the rejections are based on combinations of references.").
Appellants further argue that Caniggia does not address devices such
as Marl's traveling wave electrode configuration and, thus, is not properly
combined with Morl. Reply Br. 3.
The Examiner's reliance on Caniggia was fully set forth in the Final
Office Action as discussed above, and Appellants provide no good reason
why the argument could not have been raised in the Appeal Brief. See
generally Reply Br. We deem the argument waived for purposes of the
present appeal. 37 C.F.R. § 4I.41(b)(2). "[A]n issue not raised by an
[A]ppellant in its opening brief ... is waived." Cf Optivus Tech., Inc. v. Ion
Beam Appl'ns S.A., 469 F.3d 978, 989 (Fed. Cir. 2006) (citations and
8
Appeal2017-005793
Application 14/127,927
internal quotations omitted); Cf McBride v. Merrell Dow and Pharms., Inc.,
800 F.2d 1208, 1211 (D.C. Cir. 1986) (internal citations omitted)
("Considering an argument for the first time in a reply brief ... is not only
unfair to the appellee but also entails the risk of an improvident or ill-
advised opinion on the legal issues tendered.").
Appellants proffer further arguments as to Morl' s structure (Reply Br.
5), but these again fail to address the combination as set forth by the
Examiner and fails to "take account of the inferences and creative steps that
a person of ordinary skill in the art would employ" in overcoming the
difficulties within their level of skill. KSR Int 'l Co. v. Teleflex Inc., 550 U.S.
398, 418 (2007).
Appellants also proffer arguments directed to claim 11, as to how
"one of ordinary skill in the art ... would not arrange the two bridges at end
regions of the waveguide electrode." Reply Br. 4--5.
While set forth as being "[i]n response to the Examiner's Answer
regarding claim 11" (id. at 4), the arguments are newly raised in the Reply
Brief (see generally App. Br.) and are not reasonably in response to the
Examiner's Answer (see generally Ans.). These arguments are, accordingly,
also deemed waived for purposes of this appeal. 37 C.F.R. § 4I.41(b)(2).
As to claims 19 and 21, Appellants contend that the Examiner's
"analysis does not appear to account for the ... [limitation] 'wherein the
wide connecting structures are formed by portions of the continuous contact
structure."' App. Br. 12. Appellants contend that
Marl's design comprises a plurality of active and passive
waveguide portions (see Marl's Fig. 1, active, passive WG).
Thus, one of ordinary skill in the art might use wide electrodes
forming the active portions, which, however, would be
interrupted by the passive portions (where no electrode is
9
Appeal2017-005793
Application 14/127,927
arranged). That is, a plurality of separated, individual wide
electrodes might be used, but not one continuous structure. The
continuous contact structure has to be designed in such a way
that it contacts the waveguide in the active waveguide portions
and prevents contact in the passive waveguide portions.
Id. In the Reply Brief, Appellants further cite to Figure 8 in the instant
application, which illustrates a wide contact bridge 313 that is a continuous
contact structure. Reply Br. 6; see also Spec. 5:3-17, 14:4--14, 27
( discussing Fig. 8).
On this record, we are persuaded that the Examiner has failed to
establish a prima facie case for the claims requiring the wide connecting
structures to be formed by portions of the continuous contact structure. For
any ground of rejection, "the [E]xaminer bears the initial burden ... of
presenting aprimafacie case ofunpatentability." In re Oetiker, 977 F.2d
1443, 1445 (Fed. Cir. 1992). In meeting this burden, all the limitations of
the claims must be considered and given weight. See Stratoflex, Inc. v.
Aeroquip Corp., 713 F.2d 1530 (Fed. Cir. 1983). The Examiner's
articulated reasoning, failing to address this, falls short of that necessary for
a prima facie case. See In re Warner, 379 F.2d 1011, 1017 (CCPA 1967)
("The Patent Office has the initial duty of supplying the factual basis for its
rejection. It may not ... resort to speculation, unfounded assumptions or
hindsight reconstruction to supply deficiencies in its factual basis.").
For the reasons above, we affirm the rejection of claims over Morl, Li,
and Caniggia, but reverse the rejection as to claims 19-21.
10
Appeal2017-005793
Application 14/127,927
DECISION
The Examiner's rejection of claims 1--4 and 11-18 is AFFIRMED,
but the rejection of claims 19-21 is REVERSED.
No time period for taking any subsequent action in connection with
this appeal maybe extended under 37 C.F.R. § 1.136(a)(l).
AFFIRMED-IN-PART
11