Ex Parte Ault

Board of Patent Appeals and Interferences

Mar 10, 2005

09661653 (B.P.A.I. Mar. 10, 2005)

The opinion in support of the decision being entered today was not written
for publication and is not binding precedent of the Board.
UNITED STATES PATENT AND TRADEMARK OFFICE
____________
BEFORE THE BOARD OF PATENT APPEALS
AND INTERFERENCES
____________
Ex parte EARL R. AULT
____________
Appeal No. 2005-0616
Application No. 09/661,653
____________
ON BRIEF
____________
Before COHEN, NASE, and BAHR, Administrative Patent Judges.
NASE, Administrative Patent Judge.
DECISION ON APPEAL
This is a decision on appeal from the examiner's final rejection of claims 1, 3 to 5
and 9, which are all of the claims pending in this application.
We REVERSE.
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Application No. 09/661,653
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BACKGROUND
The appellant's invention relates to a high power laser with a trivalent titanium
liquid host (specification, p. 1). A copy of the claims under appeal is set forth in the
appendix to the appellant's brief.
The prior art references of record relied upon by the examiner in rejecting the
appealed claims are:
Kocher et al. (Kocher) 3,663,891 May 16, 1972
Chun 4,654,855 Mar. 31, 1987
Scheps 5,307,358 Apr. 26, 1994
Claims 1, 3 to 5 and 9 stand rejected under 35 U.S.C. § 103 as being
unpatentable over Kocher in view of Chun and Scheps.
Rather than reiterate the conflicting viewpoints advanced by the examiner and
the appellant regarding the above-noted rejection, we make reference to the answer
(mailed March 17, 2004) for the examiner's complete reasoning in support of the
rejection, and to the brief (filed February 19, 2004) and reply brief (filed March 30, 2004)
for the appellant's arguments thereagainst.
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Application No. 09/661,653
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OPINION
In reaching our decision in this appeal, we have given careful consideration to
the appellant's specification and claims, to the applied prior art references, and to the
respective positions articulated by the appellant and the examiner. Upon evaluation of
all the evidence before us, it is our conclusion that the evidence adduced by the
examiner is insufficient to establish a prima facie case of obviousness with respect to
the claims under appeal. Accordingly, we will not sustain the examiner's rejection of
claims 1, 3 to 5 and 9 under 35 U.S.C. § 103. Our reasoning for this determination
follows.
In rejecting claims under 35 U.S.C. § 103, the examiner bears the initial burden
of presenting a prima facie case of obviousness. See In re Rijckaert, 9 F.3d 1531,
1532, 28 USPQ2d 1955, 1956 (Fed. Cir. 1993). A prima facie case of obviousness is
established by presenting evidence that would have led one of ordinary skill in the art to
combine the relevant teachings of the references to arrive at the claimed invention. See
In re Fine, 837 F.2d 1071, 1074, 5 USPQ2d 1596, 1598 (Fed. Cir. 1988) and In re
Lintner, 458 F.2d 1013, 1016, 173 USPQ 560, 562 (CCPA 1972).
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Application No. 09/661,653
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A critical step in analyzing the patentability of claims pursuant to 35 U.S.C.
§ 103 is casting the mind back to the time of invention, to consider the thinking of one of
ordinary skill in the art, guided only by the prior art references and the then-accepted
wisdom in the field. See In re Dembiczak, 175 F.3d 994, 999, 50 USPQ2d 1614, 1617
(Fed. Cir. 1999). Close adherence to this methodology is especially important in cases
where the very ease with which the invention can be understood may prompt one "to fall
victim to the insidious effect of a hindsight syndrome wherein that which only the
invention taught is used against its teacher." Id. (quoting W.L. Gore & Assocs., Inc. v.
Garlock, Inc., 721 F.2d 1540, 1553, 220 USPQ 303, 313 (Fed. Cir. 1983)).
Most if not all inventions arise from a combination of old elements. See In re
Rouffet, 149 F.3d 1350, 1357, 47 USPQ2d 1453, 1457 (Fed. Cir. 1998). Thus, every
element of a claimed invention may often be found in the prior art. See id. However,
identification in the prior art of each individual part claimed is insufficient to defeat
patentability of the whole claimed invention. See id. Rather, to establish obviousness
based on a combination of the elements disclosed in the prior art, there must be some
motivation, suggestion or teaching of the desirability of making the specific combination
that was made by the appellant. See In re Dance, 160 F.3d 1339, 1343, 48 USPQ2d
1635, 1637 (Fed. Cir. 1998); In re Gordon, 733 F.2d 900, 902, 221 USPQ 1125, 1127
(Fed. Cir. 1984).
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The motivation, suggestion or teaching may come explicitly from statements in
the prior art, the knowledge of one of ordinary skill in the art, or, in some cases the
nature of the problem to be solved. See Dembiczak, 175 F.3d at 999, 50 USPQ2d at
1617. In addition, the teaching, motivation or suggestion may be implicit from the prior
art as a whole, rather than expressly stated in the references. See WMS Gaming, Inc.
v. International Game Tech., 184 F.3d 1339, 1355, 51 USPQ2d 1385, 1397 (Fed. Cir.
1999). The test for an implicit showing is what the combined teachings, knowledge of
one of ordinary skill in the art, and the nature of the problem to be solved as a whole
would have suggested to those of ordinary skill in the art. See In re Keller, 642 F.2d
413, 425, 208 USPQ 871, 881 (CCPA 1981) (and cases cited therein). Whether the
examiner relies on an express or an implicit showing, the examiner must provide
particular findings related thereto. See Dembiczak, 175 F.3d at 999, 50 USPQ2d at
1617. Broad conclusory statements standing alone are not "evidence." Id. When an
examiner relies on general knowledge to negate patentability, that knowledge must be
articulated and placed on the record. See In re Lee, 277 F.3d 1338, 1342-45, 61
USPQ2d 1430, 1433-35 (Fed. Cir. 2002).
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The claimed subject matter
Claims 1 and 9, the independent claims on appeal, read as follows:
1. A laser, comprising:
a laser cavity having a first lasing chamber,
a second lasing chamber,
trivalent titanium ions dissolved in a liquid host within said first lasing
chamber,
trivalent titanium ions dissolved in a liquid host within said second lasing
chamber,
a first semiconductor pumping device operatively connected to said first
lasing chamber for optically exciting said trivalent titanium ions dissolved in said
liquid host within said first lasing chamber, said first semiconductor pumping
device comprising at least one semiconductor diode for optically exciting said
trivalent titanium ions dissolved in said liquid host within said first lasing chamber,
a second semiconductor pumping device operatively connected to said
second lasing chamber for optically exciting said trivalent titanium ions dissolved
in said liquid host within said second lasing chamber, said second semiconductor
pumping device comprising at least one semiconductor diode for opdcally
exciting said trivalent titanium ions dissolved in said liquid host within said lasing
second chamber,
a closed loop circulation system for circulating said trivalent titanium ions
dissolved in a liquid host through said first lasing chamber in a first linear
direction into said closed loop circulation system and into said second lasing
chamber and through said second lasing chamber in a second linear direcdon
into said closed loop circulation system and back into said first lasing chamber,
said second linear direction being opposite to said first linear direction, said
closed loop circulation system comprising
a first portion for circulating said trivalent titanium ions dissolved in a liquid
host into and out of said first lasing chamber in said first linear direction and
a second portion for circulating said trivalent titanium ions dissolved in a
liquid host into and out of said second lasing chamber in said second direction
that is opposite to said first linear direction.
9. A laser system, comprising:
an optical cavity having
a first lasing chamber and
a second lasing chamber,
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a lasing liquid containing trivalent titanium ions dissolved in a liquid host
within said first lasing chamber and said second lasing chamber,
a first semiconductor pumping device operatively connected to said first
lasing chamber for optically exciting said trivalent titanium ions dissolved in a
liquid host within said first lasing chamber, said first semiconductor pumping
device comprising at least one semiconductor diode for optically exciting said
trivalent titanium ions in the 800 to 900 nm region,
a second semiconductor pumping device operatively connected to said
second lasing chamber for optically exciting said trivalent titanium ions dissolved
in a liquid host within said second lasing chamber, said second semiconductor
pumping device comprising at least one semiconductor diode for optically
exciting said trivalent titanium ions in the 800 to 900 nm region,
a closed loop circulation system for circulating said trivalent titanium ions
dissolved in a liquid host, said closed loop circulation system comprising
a first portion for circulating said lasing liquid containing trivalent titanium
ions dissolved in a liquid host into and out of said first lasing chamber in a first
direction, and
a second-portion for circulating said lasing liquid containing trivalent
titanium ions dissolved in a liquid host into and out of said second lasing chamber
in a second direction that is opposite to said first direction, said closed loop
circulation system including a pump and a heat exchanger.
The teachings of the applied prior art
Kocher
Kocher's invention relates to lasers and in particular to cells for lasers
which utilize a flowing liquid as the active material. Kocher teaches (column 1, lines 6-
11) that:
Solids, gases and liquids have been used as active materials in lasers.
Lasing is initiated by raising the energy levels of the atoms in the active material
from the level which they normally occupy to a higher energy level or excited
state. This process of excitation is generally accomplished in a liquid laser by a
high intensity light source.
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Figure 1 shows a schematic representation of a circulating liquid laser. A
circulating liquid laser is one in which the liquid active material continuously flows
through a closed system. The liquid active material is an inorganic solution of a
compound containing an active ion, an inorganic solvent and a Lewis acid. Although
many such solutions may be employed, in the preferred form of Kocher's invention the
active ion is tri-valent neodymium, the inorganic solvent is phosphorus oxychloride and
the Lewis acid is zirconium tetrachloride.
The circulating liquid laser consists of a resonant cavity 10 having a longitudinal
axis 11 and containing a cell 12 and mirrors 14 and 16 located adjacent the opposite
end of laser cell 12. Mirrors 14 and 16 may either be mounted externally to cell 12, as
shown in Figure 1, or may take the form of reflective coatings placed directly on the end
faces 18 and 20 of the cell. One of the mirrors, for example, mirror 14, is totally
reflective, i.e., it reflects substantially all of the light impinging upon it. The other mirror,
mirror 16, is only partially reflective in that it reflects only a portion of the light impinging
upon it while permitting the remainder of the light to be transmitted there through as the
output beam of the laser.
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Excitation means in the form of light source 22, positioned in close proximity to
cell 12 provides a source of excitation energy to the active material flowing through the
cell. The light source may take the form of a high pressure Xenon filled lamp which is
controlled by an external circuit (not shown). The walls of cell 12 are constructed of
quartz or other material which transmits radiation with negligible attenuation at the
frequency required to excite the active material.

The laser further comprises a centrifugal pump 24 for circulating the liquid active
material through the laser and heat exchanger 26 which cools the liquid after it flows out
of cell 12. Lines 28, 30 and 32 interconnect pump 24, heat exchanger 26 and cell 12.
Chun
Chun's invention pertains to pulsed gas lasers. More particularly, Chun's
invention pertains to means for circulating the gas within a pulsed gas laser. Chun's
invention uses "acoustic obstacles" to circulate the gas in the pulse discharge gas laser.
The acoustic diodes consist of passive mechanical diodes located within the gas filled
chamber of the laser, which obstacles exhibit an asymmetrical resistance to the
passage of the compression wave generated by the discharge of electrical current
through the gas. Because the obstacles exhibit less resistance to the passage of the
compression wave in one direction as compared to the opposite direction, the obstacles
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cause a net flow of gas to occur in the direction of lesser resistance. As a
consequence, the acoustic diodes interact with the compression waves to circulate the
gas through the interior of the laser.
Figure 1 depicts a cross-sectional view of the pulse discharge laser. A gas 1 is
contained within the volume enclosed by interior wall 2 and exterior wall 3 of the laser.
The portions of the gas located within the active regions 4 of the laser are excited by an
electrical current discharged in a pulsed manner between pairs of electrodes 5.
Although two discharge regions are depicted in the preferred embodiment, a single
region or more than two regions could instead be used. The discharge of electricity also
generates a pair of compression waves in the gas which propagate in opposite
directions away from the active regions 4 and which waves each have a width
approximately equal to the width of the discharge electrodes 5, i.e., the width of the
active regions 4. Although the gas mixture in the preferred embodiment of the Xe Cl
laser comprises 2% xenon (Xe) and 0.2% hydrogen chloride (HCl) in a diluent of neon
at 4 atmospheres, other combinations of gases, diluents and pressures may be used in
the invention. X-ray gun 14 preionizes the gas prior to the discharge of electricity
through active region 4.
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As shown in Figure 1, the gas 1 circulates through the pulse discharge laser in
the direction depicted by arrows 6 so as to flow successively through heat exchangers 7
and the active regions 4 of the pulse discharge laser. In operation, the gas within active
regions 4 is replaced after each discharge of current by gas coming from, and which
has been cooled by, heat exchangers 7.
A number of acoustic obstacles 8, referred to by Chun as "acoustic diodes", are
located upstream of regions 4 as depicted in Figure 1 within the volume of gas
contained by walls 2 and 3. The obstacles 8 are a series of columns running from wall
3 to wall 2 which have cupped-shaped cross sections as depicted in Figure 3. Also as
depicted in Figure 3, the depth 9 of the cupped portion of the cross-section in the
preferred embodiment is approximately the same as the width 10 of the discharge
electrode 5. As a consequence, the depth of the cup is approximately the same as the
width of the compression wave that is generated by the discharge of electricity between
electrodes 5. This depth is optimum for the reflection of the incident waves. The faces
11 of obstacles 8 that are opposite the "cups" have a rounded or more streamlined
shape as contrasted to the cupped side of the obstacles. As a consequence of the
selection of the depth of the cups and of the streamlined shape of the opposite side of
the obstacles, the obstacles 8 interact with the compression wave in the gas that is
generated by the discharge of electricity through the gas so as to cause a net flow of
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gas through the obstacles in the direction indicated by arrows 12 in Figure 3. In order to
cause the gas to circulate through the heat exchanger and the active region, as
depicted in Figure 1, the obstacles 8 all are oriented so that the openings of the cups
face downstream to the flow of the gas.
Scheps
Scheps' invention relates to tunable lasers which produce laser emission at one
or more wavelengths over a preselected wavelength range. Tunable lasers are lasers
which have the capability of emitting one or more wavelengths over a broad range of
wavelengths. These lasers are continuously tunable over a preselected range of
wavelengths and differ from non-tunable lasers which emit at certain fixed, discrete
wavelengths.
A first embodiment of a tunable laser 10 in which the gain element is used as a
tuning element is illustrated in Figure 2. The tunable laser 10 has its laser gain element
11 pumped by an argon ion laser 12. The laser gain element is an exemplary
Ti3+-activated sapphire host crystal to produce a laser beam or emission which can be
tuned within the wavelength range of about 700 nm to 850 nm.
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The tunable laser 10 includes a laser gain element 11 disposed in a resonator 15
defined by optically aligned end reflective element or mirror 17, concave fold reflective
elements 13 and 13' and an output coupler reflective mirror 19. Mirror 17 is highly
reflective while mirror 19 is partially transmissive to a laser wavelength of approximately
700 nm to 850 nm to provide the output coupling for the laser emission within the
wavelength range of about 700 nm to 850 nm from tunable laser 10. It should,
however, be noted that a different wavelength can be realized by utilizing different
reflective coatings on optical elements 17, 13, 13' and 19, or by utilizing a laser gain
element 11 which contains one or more different dopants and different associated
optical elements. In addition, other gain media such as amorphous or glass-like
materials, or liquid and gaseous materials, may be used as the laser gain element.
The examiner's rejection
In the rejection under appeal (answer, pp. 3-6) the examiner ascertained that
Kocher does not teach (1) a second lasing chamber, (2) trivalent titanium ions dissolved
in a liquid host, and (3) the pump source being a semiconductor diode. The examiner
then concluded that it would have been obvious to one of ordinary skill in the art at the
time of the invention to use (1) two chambers in Kocher, as taught by Chun, to provide
continuous and efficient lasing activity, (2) the trivalent titanium ions dissolved in a liquid
host in Kocher, as taught by Scheps, to produce a laser output with a specific
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1 The use of such hindsight knowledge to support an obviousness rejection under
35 U.S.C. § 103 is, of course, impermissible. See, for example, W. L. Gore and
Assocs., Inc. v. Garlock, Inc., 721 F.2d 1540, 1553, 220 USPQ 303, 312-13 (Fed. Cir.
1983), cert. denied, 469 U.S. 851 (1984).
wavelength, and (3) a diode pump source in Kocher, as taught by Scheps, since
choosing an optimum pumping device involves routine skill in the art.
The appellant's argument
The appellant argues (brief, pp. 7-13; reply brief, pp. 2-5) that absent the use of
hindsight knowledge derived from the appellant's own disclosure1 there is no reason for
a person of ordinary skill in the art at the time the invention was made to have modified
Kocher so as to arrive at the claimed subject matter. The appellants argue that the
applied prior art does not suggest a laser having a closed loop circulation system for
circulating trivalent titanium ions dissolved in a liquid host through a first lasing chamber
in a first linear direction and through a second lasing chamber in a second linear
direction opposite to the first linear direction.
Our view
After reviewing the teachings of the applied prior art, we fail to find any
motivation, suggestion or teaching therein of the desirability of making the specific
combination that was made by the appellant. That is, there is no rationale in the applied
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prior art for a person of ordinary skill in the art at the time the invention was made to
have modified Kocher so as to arrive at the claimed subject matter. While each element
of the claimed invention may well be found in the applied prior art, such is insufficient to
defeat patentability of the claimed invention absent some motivation, suggestion or
teaching of the desirability of making the specific combination that was made by the
appellant. In this case, it is our view that there is none.
For the reasons set forth above, the decision of the examiner to reject claims 1
and 9, and claims 3 to 5 dependent thereon, under 35 U.S.C. § 103 is reversed.
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CONCLUSION
To summarize, the decision of the examiner to reject claims 1, 3 to 5 and 9 under
35 U.S.C. § 103 is reversed.
REVERSED
IRWIN CHARLES COHEN )
Administrative Patent Judge )
)
)
)
) BOARD OF PATENT
JEFFREY V. NASE ) APPEALS
Administrative Patent Judge ) AND
) INTERFERENCES
)
)
)
JENNIFER D. BAHR )
Administrative Patent Judge )
Appeal No. 2005-0616
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EDDIE E SCOTT
PATENT ATTORNEY LAWRENCE LIVERMORE NATIONAL LAB
PP BOX 808-L-703
LIVERMORE, CA 94551
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