Ex Parte Way

Board of Patent Appeals and Interferences

Apr 15, 2008

10041853 (B.P.A.I. Apr. 15, 2008)

UNITED STATES PATENT AND TRADEMARK OFFICE
____________

BEFORE THE BOARD OF PATENT APPEALS
AND INTERFERENCES
____________

Ex parte DAVID G. WAY
____________

Appeal 2007-3025
Application 10/041,853
Technology Center 2600
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Decided: April 15, 2008
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Before ANITA PELLMAN GROSS, MAHSHID D. SAADAT, and JOHN A.
JEFFERY, Administrative Patent Judges.

GROSS, Administrative Patent Judge.

DECISION ON APPEAL
STATEMENT OF THE CASE
Way (Appellant) appeals under 35 U.S.C. § 134 from the Examiner's
final rejection of claims 1 through 9 and 11 through 20, which are all of the
claims pending in this application. We have jurisdiction under 35 U.S.C.
§ 6(b).
Appellant's invention relates to selectable dispersion enhancement and
dispersion compensation for optical fibers. (Spec. 3-4). Claim 1 is
illustrative of the claimed invention, and it reads as follows:
Appeal 2007-3025
Application 10/041,853

1. A dispersion compensation system comprising:

a dispersion compensation module (DCM) operable to receive optical
input and provide optical output having a negative dispersion relative to the
optical input; and

a dispersion enhancement module (DEM) adapted to be optically
coupled between the DCM and an optical fiber having a positive dispersion,
the DEM operably including a plurality of dispersion enhancement fibers
and operable to selectively increase the positive dispersion provided by the
optical fiber by a selected one of a plurality of amounts and to provide the
optical input to the DCM, the optical input having a positive dispersion
substantially equal to the positive dispersion of the optical fiber plus the
selected one of the amounts of dispersion in the DEM.

The prior art references of record relied upon by the Examiner in
rejecting the appealed claims are:
Delavaux US 5,608,562 Mar. 04, 1997
Keys US 6,456,773 B1 Sep. 24, 2002
(filed Apr. 17, 2000)
Feinberg US 2003/0031433 A1 Feb. 13, 2003
(filed Sep. 26, 2001)
Colbourne US 6,654,564 B1 Nov. 25, 2003
(filed Aug. 07, 2000)

Claims 1 through 9, 11, 13 through 17, 19, and 20 stand rejected
under 35 U.S.C. § 103 as being unpatentable over Colbourne in view of
Delavaux and Keys.
Claims 12 and 18 stand rejected under 35 U.S.C. § 103 as being
unpatentable over Colbourne in view of Delavaux, Keys, and Feinberg.
We refer to the Examiner's Answer (mailed January 5, 2007) and to
Appellant's Brief (filed October 10, 2006) and Reply Brief (filed March 5,
2007) for the respective arguments.
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Application 10/041,853

SUMMARY OF DECISION
As a consequence of our review, we will affirm the obviousness
rejections of claims 1 through 9 and 11 through 20.

OPINION
The Examiner asserts (Ans. 3-4) that Colbourne teaches a dispersion
compensation system with both a compensation module and an enhancement
module, but do not disclose that the enhancement module includes
dispersion enhancement fibers. The Examiner asserts (Ans. 4) that
Delavaux discloses variable dispersion compensation using switched
dispersion compensation fibers controlled by a controller and that Keys
discloses using positive and negative dispersion segments in each dispersion
compensation device.
Appellant contends (App. Br. 12-13) that the proposed combination
fails to teach all of the claimed limitations. Specifically, Appellant contends
(App. Br. 13 and 16-17 and Reply Br. 6-7) that Colbourne teaches away
from using dispersion enhancement fibers. Appellant further contends (App.
Br. 14-15 and Reply Br. 3 and 7) that Delavaux and Keys teach away from
the combination as Delavaux teaches using compensation fibers with a
negative dispersion and Keys teaches that compensation fibers are coupled
together to provide a net dispersion to offset the dispersion of an optical
fiber. Last, Appellant contends (App. Br. 17-18 and Reply Br. 4-6) that the
Examiner has provided no motivation to combine the references. The issue
before us, therefore, is whether the combination of Colbourne, Delavaux,
and Keys would have been obvious, and whether the combination teaches or
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Application 10/041,853

suggests using controllable dispersion enhancement fibers in addition to a
dispersion compensation module.
Colbourne discloses (col. 10, ll. 20-45) using two tunable filters,
opposite in sign, with the total dispersion of the two being either increasing
or decreasing. Further, Colbourne discloses (col. 10, l. 67-col. 11, l. 2) that
the filters can compensate for the dispersion slope after conventional
dispersion compensation. In other words, Colbourne suggests a
conventional compensation module and a compensation filter or pair of
filters which can have a positive net compensation, or dispersion
enhancement. We agree with Appellant, though, that Colbourne appears to
teach away from using dispersion compensating fibers for the controllable
dispersion enhancement by stating that the fibers cannot compensate for the
wavelength dependence of dispersion (see col. 9, ll. 12-15).
However, Delavaux discloses (col. 4, ll. 23-36) a unit formed of
dispersion compensating fibers that can compensate for several wavelengths
simultaneously. Thus, Delavaux solves the problem posed by Colbourne as
to using fibers for dispersion enhancement. Further, Keys discloses (col. 1,
ll. 57-63) that proposed dispersion compensating modules include both
positive dispersion and negative dispersion compensating fibers, wherein the
net dispersion offsets the dispersion associated with an optical fibers. Thus,
Keys further supports the combination of an enhancement module with
positive dispersion compensating fibers and a compensation module with
negative dispersion. Accordingly, the combined teachings and suggestions
of the three references do suggest using dispersion enhancement fibers.
We are not persuaded by Appellant's argument that Delavaux and
Keys teach away from using dispersion enhancing fibers. Colbourne teaches
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Application 10/041,853

dispersion enhancement with positive dispersion. Delavaux teaches that
fibers can be used to compensate for dispersion at different wavelengths.
Even if Delavaux used only negative dispersion, Delavaux's teachings
should be interpreted more broadly as suggesting using fibers for adjustable
dispersion. Similarly, Keys is not limited to negative dispersion
compensation, as Keys explicitly discloses positive and negative
compensation to offset dispersion associated with optical fibers.
As to Appellant's last contention, that there is no motivation to
combine the references, the Supreme Court has held that in analyzing the
obviousness of combining elements, a court need not find specific teachings,
but rather may consider "the background knowledge possessed by a person
having ordinary skill in the art" and "the inferences and creative steps that a
person of ordinary skill in the art would employ." See KSR Int’l Co. v.
Teleflex Inc., 127 S. Ct. 1727, 1740-41 (2007). To be nonobvious, an
improvement must be "more than the predictable use of prior art elements
according to their established functions," and the basis for an obviousness
rejection must include an "articulated reasoning with some rational
underpinning to support the legal conclusion of obviousness.” Id. Here,
Colbourne states (col. 9, ll. 12-16) that dispersion compensating fibers may
be used to provide a fixed positive or negative dispersion compensation for
optical fibers but cannot compensate for wavelength dependence of
dispersion. Thus, Colbourne suggests that compensation includes positive
dispersion, or enhancement, and that it would be desirable to use
controllable fibers for dispersion compensators. Since Delavaux teaches
how to control dispersion compensation fibers, and Keys further suggests
dispersion compensation fibers may provide either positive or negative
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dispersion, the combined teachings of the three references would have
suggested an enhancement module of dispersion compensation fibers as well
as a compensation module. The combination is no more than the predictable
use of prior art elements. Accordingly, we will sustain the obviousness
rejection of claims 1 through 9, 11, 13 through 17, 19, and 20 over
Colbourne in view of Delavaux and Keys.
Regarding the rejection of claims 12 and 18, the Examiner added
Feinberg to the primary combination. However, Appellant's sole argument
(App. Br. 18) is that Feinberg fails to cure the alleged deficiency of
Colbourne, Delavaux, and Keys. Since we have found no such deficiency,
we will sustain the obviousness rejection of claims 12 and 18.

ORDER
The decision of the Examiner rejecting claims 1 through 9 and 11
through 20 under 35 U.S.C. § 103 is affirmed.
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

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