Ex Parte Lee et al

Patent Trial and Appeal Board

Dec 26, 2012

12197658 (P.T.A.B. Dec. 26, 2012)

UNITED STATES PATENT AND TRADEMARK OFFICE
_____________

BEFORE THE PATENT TRIAL AND APPEAL BOARD
_____________

Ex parte MICHAEL G. LEE, ALEXEI L. GLEBOV,
and DASHUN STEVE ZHOU
_____________

Appeal 2010-007651
Application 12/197,658
Technology Center 2800
______________

Before DAVID M. KOHUT, BRYAN F. MOORE, and MICHAEL J.
STRAUSS, Administrative Patent Judges.

MOORE, Administrative Patent Judge.

DECISION ON APPEAL

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This is a decision on appeal under 35 U.S.C. § 134(a) of the Final
Rejection of claims 1-8. App. Br. 2. We have jurisdiction under 35
U.S.C. § 6(b).
We AFFIRM.

INVENTION
The invention is directed to optics and more particularly to an
optical modulator See Spec. 1.
Claim 1 is exemplary of the invention and reproduced below:
1. An optical modulator comprising:
an input waveguide;
a splitting point operable to split an incoming continuous
wave light beam received via the input waveguide into a first
light beam and a second light beam, the incoming continuous
wave light beam comprising a first wavelength of light and a
second wavelength of light;
a first interaction arm coupled to the input waveguide at
the splitting point, the first interaction arm having a first length
L1 and operable to transmit the first light beam;
a second interaction arm coupled to the input waveguide
at the splitting point, the second interaction arm having a
second length L2 unequal in length to the first interaction arm
and operable to transmit the second light beam; and
an output waveguide coupled to the first interaction arm
and the second interaction arm at a recombination point such
that the first light beam and second light beam are combined
into an output modulated light beam,
wherein the first interaction arm and the second
interaction arm comprise an electro-optic material with a
refractive index that changes according to a modulation
stimulus, the electro-optic material having a first refractive
index n1 before the modulation stimulus is applied, and a
second refractive index n2 after the modulation stimulus is
applied, the first length L1 and the second length L2 comprising
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lengths such that the output modulated light beam does not
comprise the first wavelength of light and the second
wavelength of light when the modulation stimulus is applied,
and comprises the first wavelength of light and the second
wavelength of light when the modulation stimulus is not
applied, the first wavelength of light and the second wavelength
of light being substantially unattenuated when the stimulus is
not applied.

REFERENCES
Wolf US 5,611,007 Mar. 11, 2007

Ed. L. Wooten, et al. (Wooten) Rapidly tunable narrowband
wavelength filter using LiNbO3 unbalanced Mach-Zehnder
interferometers. IEEE Journal of Lightwave Technology, vol. 14, no.
11 pp. 2530-2536, November 1996.

REJECTIONS AT ISSUE
Claims 1, 2, 5, and 6 stand rejected under 35 U.S.C. § 102(b) as being
anticipated by Wooten. Ans. 4-7.
Claims 3, 4, 7, and 8 stand alternatively rejected under 35 U.S.C.
§ 103(a) as being unpatentable over Wooten and Wolf. Ans. 8-13.

ISSUES
1. Did the Examiner err finding that Wooten discloses “the output
modulated light beam does not comprise the first wavelength of
light and the second wavelength of light when the modulation
stimulus is applied, and comprises the first wavelength of light
and the second wavelength of light when the modulation
stimulus is not applied, the first wavelength of light and the
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second wavelength of light being substantially unattenuated
when the stimulus is not applied [,]” as recited in claim 1?
2. Did the Examiner err finding that Wolf discloses the limitations
in claim 4?
ANALYSIS
35 U.S.C. § 102(b) - Wooten
Claims 1, 2, 5, and 6
With respect to the above rejection, Appellants present arguments
with respect to claim 1. As to Claim 1, Appellants argue that “a three-stage
filter in which one out of eight wavelengths of light is passed when a
stimulus is applied” does not meet the limitation cited in issue 1 above.
App. Br. 12. Appellants argue that “Figure 2 illustrates how one set of
frequencies are passed when no stimulus is applied, and a completely
different set of frequencies are attenuated when a stimulus is applied.” Id. at
13. Finally, Appellants argue, as to the Examiner’s statement that a voltage
equal to the half-wave voltage is inherent, “merely stating that a certain
voltage inherently exists to produce a claimed effect does not meet or even
address this standard that the allegedly inherent characteristic necessarily
flows from the prior art.” Id at 14. We are not persuaded by these
arguments.
As to Figure 2, the Examiner notes that Figure 2 shows “an inherent
sinusoidal transmission characteristic” of the Mach-Zehnder modulator with
three different arms length differences. Ans. at 14-15. The Examiner is
relying on the fact that the curve shows that, for a given arm length
difference, there is a characteristic when no stimulus is applied. As the
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Examiner points out, Fig. 2 shows the characteristic curves when the voltage
is fixed at zero. Ans. 14. Therefore, Figure 2 does not show a completely
different set of frequencies when a stimulus (i.e., non-zero voltage) is
applied.
What Fig. 2 does show is two or more wavelengths (such as 100 GHz
and 200 GHz on the solid curve) that correspond to the maxima (a
Transmittance of 1) in the absence of a modulation stimulus (V=0) and
hence both wavelengths are transmitted through the output waveguide
substantially unattenuated. See Ans. 6 (citing Wooten Fig. 2.) Thus,
Wooten discloses “the output modulated light beam . . . comprises the first
wavelength of light and the second wavelength of light when the modulation
stimulus is not applied, the first wavelength of light and the second
wavelength of light being substantially unattenuated when the stimulus is
not applied.” Therefore Wooten satisfies at least the final portion of the
disputed limitation.
Claim 1 also recites “the output modulated light beam does not
comprise the first wavelength of light and the second wavelength of light
when the modulation stimulus is applied.” As noted above, Appellants’
argue that the Examiner has improperly relied on inherency to show this
limitation.
“A single prior art reference that discloses, either expressly or
inherently, each limitation of a claim invalidates that claim by anticipation.”
Perricone v. Medicis Pharmaceutical Corp., 432 F.3d 1368, 1375 (Fed. Cir.
2005). In Cruciferous Sprout, the court stated “[i]t is well settled that a prior
art reference may anticipate when the claim limitations not expressly found
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in that reference are nonetheless inherent in it.” In re Cruciferous Sprout
Litigation, 301 F.3d 1343, 1349 (Fed. Cir. 2002). Inherent anticipation
requires that the missing descriptive material is “necessarily present,” not
merely probably or possibly present in the prior art. See In re Robertson,
169 F.3d 743, 745 (Fed. Cir. 1999).
The Examiner notes that, according to Eq. 1, when a modulation
stimulus is applied with a magnitude equal to the half-wave switching
voltage Vπ, the transmission curve shifts by a half a period. Ans. 6.
Appellants do not explain why Eq. 1 of Wooten does not lead to this result.
Whether the rejection is based on “inherency” under 35 U.S.C. § 102, on
“prima facie obviousness” under 35 U.S.C. § 103, jointly or alternatively,
the burden of proof is the same, and its fairness is evidenced by the PTO’s
inability to manufacture products or to obtain and compare prior art
products. In re Best, 562 F.2d 1252, 1254-55 (CCPA 1977). Therefore, we
agree with the Examiner’s assertion regarding Eq. 1 of Wooten. See Ans. 6.
With reference to Fig. 2, if the solid curve is shifted by a half period
then the maxima that was shown at 100 GHz shifts to the minima shown at
150 GHz and the same with the maxima 200 GHz, which will shift to the
minima shown at 250 GHz. Ans. 6. Figures 4 and 5 shows an arrangement
where such an effect is achieved. Id. As illustrated therein, eight
wavelengths λ1-λ8 are input to the modulator, four wavelengths λ2, λ4, λ6, λ8
are switched off and four wavelengths λ1, λ3, λ5, λ7are switched on for the
same stimulus voltage input. Ans. 5. Thus initial portion of the disputed
limitation is also satisfied by Wooten. Accordingly, based on the forgoing,
we agree with the Examiner that the limitations of the claim 1 are each
disclosed necessarily if not explicitly by Wooten. Therefore, for the reasons
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stated above, we sustain the Examiner’s rejection of claim 1 and claim 2
which depends from claim 1 and claims 5, and 6 which are not separately
argued.
35 U.S.C. § 103(a) - Wooten and Wolf
Claims 3, 4, 7, and 8
With respect to the above rejection, Appellants provide arguments
regarding claim 4. Claim 4 recites “wherein the difference ΔL between L1
and L2 is found according to [a certain] equation.” Appellants also argue
“the Examiner makes broad generalizations and assumptions that are not
supported by the references” and thus the references do not show deriving or
calculating using the claimed equation. App. Br. 16-17. We find that an
ordinarily skilled artisan would have appreciated that optimizing the ΔL by
derivation of the cited equation, in light of the teachings of Wooten and
Wolf, involves only a design choice using routine skill in the art. See Ans.
16.
A design choice may be an acceptable rationale for an obviousness
rejection when a claimed product merely arranges known elements in a
configuration that provides no novel or unexpected results. See In re Kuhle,
526 F.2d 553, 555 (CCPA 1975). An improvement in the art is obvious if
“it is likely the product not of innovation but of ordinary skill and common
sense.” KSR Int'l v. Teleflex Inc., 550 U.S. 398, 421 (2007). Moreover, the
obviousness analysis “need not seek out precise teachings directed to the
specific subject matter of the challenged claim, for a court [or the PTO] can
take account of the inferences and creative steps that a person of ordinary
skill in the art would employ.” KSR, 550 U.S. at 418. The knowledge to be
taken into account includes knowledge generally available to a person
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having ordinary skill in the art, and facts admittedly well known in the art.
See In re Paulsen, 30 F.3d 1475, 1480 (Fed. Cir. 1994) (“[A] prior art
reference must be ‘considered together with the knowledge of one of
ordinary skill in the pertinent art.”’); In re Sovish, 769 F.2d 738, 743 (Fed.
Cir. 1985) (skill is presumed on the part of the artisan, rather than the lack
thereof); and In re Nomiya, 509 F.2d 566, 570-71 (CCPA 1975) (The
admittedly known prior art disclosed in an appellant's specification may be
used in determining the patentability of a claimed invention.).
Here Wooten shows the need to properly design an optical modulator
so that at least two wavelengths are switched off for the same applied
switching voltage. The disclosed modulator also would be recognized by
one skilled in the art to operate such that it would transmit the at least two
wavelengths substantially unattenuated when no voltage is applied, as
detailed above, thus disclosing the desirability of deriving or solving a
known set of equations to calculate a required ΔL. Ans. 16. We agree with
the Examiner that “[s]ince the transmission/switching characteristic T
depends on ΔL, as evident from Eqs. (1) - (2) and Fig. 2, Wooten, at the very
least, makes the need to optimize ΔL obvious to a person of ordinary skill in
the art, while the corresponding analysis would have been very
straightforward and well within the skill of such person.” Id. Additionally,
we note that equation 4 of Wolf shows a deviation of a similar equation
based on a Mach-Zehnder device with the same variables. Appellants have
not argued, nor do we find, any unexpected results in regard to deriving the
equation recited in claim 4. Therefore, for the reasons stated above, we
sustain the Examiner’s rejection of claim and claims 3, 7, and 8 which are
not separately argued.
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DECISION
The Examiner’s decision to reject claims 1-8 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)(1)(iv).

AFFIRMED

ELD