Ex Parte Asai et al

Patent Trials and Appeals Board

Jun 25, 2019

14534373 - (D) (P.T.A.B. Jun. 25, 2019)

UNITED STA TES p A TENT AND TRADEMARK OFFICE
APPLICATION NO. FILING DATE
14/534,373 11/06/2014
93263 7590 06/27/2019
Tomoko Nakajima
Cermak Nakajima & McGowan LLP
127 S. Peyton St., Suite 200
Alexandria, VA 22314
FIRST NAMED INVENTOR
Keiichiro Asai
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.
1027-0072 3377
EXAMINER
TRAN, HOANG Q
ART UNIT PAPER NUMBER
2874
NOTIFICATION DATE DELIVERY MODE
06/27/2019 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):
TNakajima@cnmiplaw.com
ip@cnmiplaw.com
PTOL-90A (Rev. 04/07)
UNITED STATES PATENT AND TRADEMARK OFFICE
BEFORE THE PATENT TRIAL AND APPEAL BOARD
Ex parte KEIICHIRO ASAI and SHOICHIRO Y AMAGUCHI 1
Appeal2018-005169
Application 14/534,373
Technology Center 2800
Before DONNA M. PRAISS, CHRISTOPHER C. KENNEDY, and
BRIAND. RANGE, Administrative Patent Judges.
KENNEDY, Administrative Patent Judge.
DECISION ON APPEAL
This is an appeal under 35 U.S.C. § 134(a) from the Examiner's
decision rejecting claims 1-8, 10-15, 17, 20, and 21. We have jurisdiction
under 35 U.S.C. § 6(b). We REVERSE.
BACKGROUND
The subject matter on appeal relates to optical waveguide devices and
associated methods of producing optical waveguide devices. E.g., Spec. ,r 1;
Claims 1, 10. Claim 1 is reproduced below from page 10 ( Claims
Appendix) of the Appeal Brief:
1 The Appellant is the Applicant, NGK INSULATORS, LTD., which is also
identified as the real party in interest. See App. Br. 2.
Appeal2018-005169
Application 14/534,373
1. An optical waveguide device comprising;
a thin layer consisting of an optical material selected from the
group consisting oflithium niobate, lithium tantalate, and lithium
niobate-lithium tantalate, wherein said optical material is
optionally doped with a metal element or a rare earth element;
and
a ridge portion loaded directly on said thin layer, said ridge
portion comprising tantalum pentoxide and having a trapezoidal
shape viewed in a cross section perpendicular to a direction of
propagation of a light,
wherein said ridge portion directly contacts said optical material;
and
wherein said light is confined to and propagates in said thin layer
under said ridge portion.
REJECTIONS ON APPEAL
The claims stand rejected under 35 U.S.C. § I03(a) as follows:
1. Claims 1-5, 7-13, 15, 17, 20, and 21 as unpatentable over Rabiei
(US 2014/0004638 Al, published Jan. 2, 2014), Kondou (US 2011/0243493
Al, published Oct. 6, 2011), and Anderson (US 2012/0269478 Al,
published Oct. 25, 2012);
2. Claims 6 and 14 as unpatentable over Rabiei, Kondou, Anderson,
and Yamaguchi (US 2007/0189689 Al, published Aug. 16, 2007).
ANALYSIS
Claim 1 requires, inter alia, a "a thin layer consisting of an optical
material selected from the group consisting of lithium niobate, lithium
tantalate, and lithium niobate-lithium tantalate, wherein said optical material
is optionally doped with a metal element or a rare earth element" ( emphasis
added), and a "ridge portion" that "directly contacts said optical material."
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Application 14/534,373
Claim 1 further requires that "light is confined to and propagates in said thin
layer under said ridge portion." The Specification discloses that
confinement of light is "improve[d]" due to the ridge portion having a
refractive index "near that of the optical material." Spec. ,r 1 7. The
Appellant asserts, and the Examiner does not dispute, that lithium niobate
has a refractive index of 2.30, lithium tantalate has a refractive index of 2.18,
and tantalum pentoxide has a refractive index of 2.13. App. Br. 5.
The Examiner finds that Figures 2a through 2e of Rabiei depict an
optical waveguide device comprising ridge portion 208 that directly contacts
a "thin layer," which the Examiner identifies as the combination of layers
203 and 204 of Rabiei. Final Act. 3 ("203 and 204 make[] up the thin
layer"). Figure 2c of Rabiei is reproduced below.
Figure 2c of Rabiei shows ridge portion 208 directly on layers 203 and 204,
which rest on low refractive index cladding layer 202, which rests on base
substrate 201. Rabiei ,r 3 7. Rabiei identifies layer 203 as "a thin slab layer
of high refractive index material (203) such as ... ferroelectric crystals ( e.g.
lithium niobate ), or lithium tantalate." Rabiei ,r 37. Rabiei identifies layer
204 as a silicon dioxide diffusion barrier layer that "is needed to prevent
diffusion of oxygen from the slab core region (203) to the refractory metal
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Application 14/534,373
layer (205). This layer is needed if the slab core layer is lithium niobate or
lithium tantalate." Id. ,r 51.
In the Answer, the Examiner acknowledges that layer 204 is made of
silicon dioxide rather than one of the compounds recited by claim 1,
reiterates the finding that "the multilayer structure of '204/203' together
serves as 'a thin layer made of lithium niobate or lithium tantalate' as
required by claim 1," and interprets claim 1 as permitting the "thin layer" to
"be made of other unknown materials" (presumably such as the silicon
dioxide of layer 204) because claim 1 recites that the "optical material is
optionally doped with a metal element or a rare earth element." Ans. 3.
Thus, notwithstanding the use of the words "consisting of' in claim 1, the
Examiner determines that "the multilayer structure of 203/204 is considered
a thin layer of optical material recited in claim 1." Id.
That rationale is not persuasive. "'Consisting of is a term of patent
convention meaning that the claimed invention contains only what is
expressly set forth in the claim." Norian Corp. v. Stryker Corp., 363 F.3d
1321, 1331 (Fed. Cir. 2004). "[I]f a patent claim recites 'a member selected
from the group consisting of A, B, and C,' the 'member' is presumed to be
closed to alternative ingredients D, E, and F." Multilayer Stretch Cling Film
Holdings, Inc. v. Berry Plastics Corp., 831 F.3d 1350, 1358 (Fed. Cir.
2016).
Claim 1 recites that the thin layer "consist[ s] of' an optical material,
and that the optical material is "selected from the group consisting of lithium
niobate, lithium tantalate, and lithium niobate-lithium tantalate." Claim 1
further recites that the optical material may optionally be "doped with a
metal element or a rare earth element." In view of the claim language and
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Application 14/534,373
the principles of claim interpretation set forth above, the "optical material"
of claim 1 can be only lithium niobate, lithium tantalate, or lithium niobate-
lithium tantalate, optionally doped with a metal element or a rare earth
element. Because the "thin layer" of claim 1 "consists of' the optical
material, the "thin layer," in tum, can be only lithium niobate, lithium
tantalate, or lithium niobate-lithium tantalate, optionally doped with a metal
element or a rare earth element.
Because layer 204 of the "thin layer" identified by the Examiner is
silicon dioxide (not a metal element or rare earth element dopant), and ridge
structure 208 sits directly atop layer 204 and is not in direct contact with
layer 203, the arrangement of Rabiei Figure 2 relied on by the Examiner
falls beyond the scope of claim 1 as properly interpreted. Additionally, even
if layer 204 were a metal element or a rare earth element, the Examiner does
not persuasively explain how or why layer 204 could be considered a dopant
by a person of ordinary skill in the art.
The Examiner's discussions of Figures 1 and 7 of Rabiei and of
Anderson are also unpersuasive. See Ans. 5. In Figure 1 of Rabiei,
layer 102 is not disclosed as being a compound that falls within the scope of
claim 1 but is instead identified as a low refractive index material such as
silicon dioxide. See Rabiei ,r 60. That is consistent with other disclosures in
Rabiei indicating that what the Examiner identifies as Rabiei' s "ridge
portion" is of higher refractive index than what the Examiner identifies as
Rabiei's "thin layer." E.g., id. ,r 37 (describing "high refractive index
material ... deposited on a low refractive index cladding" which is
"deposited or grown on a base substrate"). The Appellant asserts, and the
Examiner does not persuasively dispute, that Rabiei' s arrangement results in
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light being confined to what the Examiner identifies as Rabiei' s "ridge
portion." App. Br. 7. Claim 1 requires light confined to the thin layer.
The Examiner identifies element 705 of Figure 7 as a "ridge portion,"
Ans. 5, but Rabiei describes element 705 as "coupling layer," e.g., id. ,r 80,
and the Examiner provides no persuasive explanation as to how coupling
layer 705 corresponds to or is otherwise similar to ridge portion 208 of
Figure 2. The Examiner also fails to identify a disclosure in Rabiei that
layers 704 and 705 of Figure 7 constitute compounds that fall within the
scope of claim 1. In that regard, we observe that the Examiner does not
persuasively dispute the Appellant's argument that Rabiei discloses that
layer 705 should have a refractive index that is greater than or equal to that
of layer 704 and would not lead to a ridge portion of tantalum pentoxide and
a thin layer portion of lithium niobate, lithium tantalate, or lithium niobate-
lithium tantalate. See App. Br. 7-8. On this record, the Examiner does not
adequately explain how Figures 1 and 7 of Rabiei would have led to the
subject matter of claim 1 or to the elimination of layer 204 from Rabiei
Fig. 2, particularly given Rabiei' s explicit teaching that layer 204 "is needed
to prevent diffusion of oxygen from the slab core region (203) to the
refractory metal layer 205) ... if the slab core layer is lithium niobate or
lithium tantalate." See Rabiei ,r 51 ( emphasis added).
Relying on, e.g., layers 36 and 32 of Anderson Figures 3A and 4A, the
Examiner finds that Anderson discloses a tantalum pentoxide material in
direct contact with a lithium niobate material. See Final Act. 7-8; Ans. 6.
The Examiner finds that such a configuration could be used in Rabiei "to
enhance the modulating and switch abilities of the TE / TM modes within
the waveguide." Final Act. 4--5. However, as the Examiner explains in the
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Answer, in Anderson a lower cladding 36 is "used to confine light within the
core (32)." Ans. 5. Although difficult to discern in Figure 3A, Figure 4A
shows, and Anderson expressly states, that core 32 rests "[ o ]n top of the
lower cladding 36," and that layer 32 has a higher refractive index than
layer 36. Anderson ,r,r 99-100. Thus, as with Rabiei, in the portions of
Anderson relied on by the Examiner, light is confined within an upper layer
that the Examiner equates with the ridge portion of claim 1, whereas claim 1
requires that the "light is confined to and propagates in said thin layer under
said ridge portion." The Examiner does not adequately establish that a
person of ordinary skill in the art would have been motivated to modify
Anderson ( or to modify Rabiei in view of Anderson) to select materials such
that light is confined to and propagates in the thin layer, as required by
claim 1. Moreover, it is undisputed that tantalum pentoxide has a lower
refractive index than, e.g., lithium niobate. The Examiner's proposal
appears to be inconsistent with the disclosure of Anderson ,r,r 99-100 that
layer 32 have a higher index of refraction than layer 36, because the
Examiner's proposal requires that layer 32 have a lower refractive index
than layer 36.
Additionally, the Examiner's findings continue to rely on an
interpretation of claim 1 as permitting compounds other than the compounds
recited by claim 1 to make up the thin layer. See Ans. 5 ("Anderson further
indicates lower cladding layers maybe made of more than one material[]
using a multilayer structure[] to adjust the refractive index of the lower
cladding."), 6 ("The examiner would like to note that claim 1 does indicate
that the thin optical materials can be made of more than one material." /
"[T]he overall refractive index cladding layer of 102 can be modified with
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additional materials that is not made of Lithium Niobate." / "The
modification suggested by the examiner would still be able to yield the
limitations of the thin layer (lithium niobate mixed with other layers) being
in direct contact with the ridge portion .... "). The Examiner fails to
identify what "additional materials" Anderson's lithium niobate might be
"mixed with" to maintain desired refractive indexes, and therefore fails to
establish that Anderson suggests a "thin layer" that falls within the scope of
claim 1, as interpreted above. In that regard, we observe that Anderson
discloses, e.g., "interspersed layers of silicon nitride, silicon dioxide and/or
silicon oxynitride," Anderson ,r 99, which would not fall within the scope of
the thin layer of claim 1.
On this record, the Examiner has not adequately established that the
prior art teaches or suggests a device that falls within the scope of claim 1.
We reverse the Examiner's rejection of claim 1.
The Examiner's discussion of the other claims on appeal does not
remedy the error identified above. Accordingly, we likewise reverse the
Examiner's rejection of claims 2-8, 10-15, 17, 20, and 21.
CONCLUSION
We REVERSE the Examiner's rejections of claims 1-8, 10-15, 17,
20, and 21.
REVERSED
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