Ex parte Knapp

Board of Patent Appeals and Interferences

Sep 29, 1998

08187364 (B.P.A.I. Sep. 29, 1998)

Application for patent filed January 26, 1994.1
THIS OPINION WAS NOT WRITTEN FOR PUBLICATION
The opinion in support of the decision being entered today
(1) was not written for publication in a law journal and
(2) is not binding precedent of the Board.
Paper No. 25
UNITED STATES PATENT AND TRADEMARK OFFICE
_____________
BEFORE THE BOARD OF PATENT APPEALS
AND INTERFERENCES
_____________
Ex parte ALAN G. KNAPP
_____________
Appeal No. 96-0236
Application 08/187,3641
______________
ON BRIEF
_______________
Before MARTIN, TORCZON, and CARMICHAEL, Administrative Patent
Judges.
MARTIN, Administrative Patent Judge.
DECISION ON APPEAL
This is an appeal under 35 U.S.C. § 134 from the
examiner's rejection of claim 1-5, 9-14, and 16 under 35
U.S.C. § 103. The remaining pending claims, i.e., claims 5-8
Appeal No. 96-0236
Application 08/187,364
The Kuijk reference explains that MIM stands for metal-2
insulator-metal (p. 2, line 33).
- 2 -
and 15, stand objected to for depending on rejected claims.
We reverse.
The invention relates to drive voltage control for a
matrix display device in which each display element has an
electro-optical elements connected in series with a two-
terminal non-linear switching device, which may be of the MIM2
type (Spec. at 5, lines 14-15). The problem to be solved is
that the threshold voltage characteristic of the non-linear
devices may change over time, thereby altering the drive
currents in the electro-optical elements and thus the
brightness of thereof (Spec. at 2, lines 10-15). Appellant's
invention solves this problem by measuring the drive current
through at least one non-linear device and adjusting the drive
voltages to compensate for variations due to aging.
There are only two independent claims on appeal,
apparatus claim 1 and method claim 13, which read as follows:
1. A matrix display device comprising sets of row
and column address conductors, a row and column array of
picture elements operable to produce a display, each of
which comprises an electro-optic display element connected in
series with a two terminal non- linear device exhibiting a
Appeal No. 96-0236
Application 08/187,364
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threshold characteristic between a row conductor and a column
conductor, and picture element drive means connected to the
sets of address conductors for applying drive voltages to the
picture elements comprising a scanning signal drive circuit
for applying selection signals to the conductors of one set
and a data signal drive circuit for applying data signals to
the conductors of the other set, characterised in that the
drive means includes a sensing circuit which is arranged to
provide a control signal indicative of electrical current
flowing in at least one address conductor of the one set in
response to the application of selection signals to that
address conductor, and a voltage control circuit to which the
control signal is supplied for determining the drive voltages
applied by the drive means to the picture elements in
accordance with the value of the control signal.
13. A method of operating a matrix display device
comprising sets of row and column address conductors, a row
and column array of picture elements operable to produce a
display, each of which comprises an electro-optic display
element connected in series with a two terminal non-linear
device exhibiting a threshold characteristic between a row
conductor and a column conductor, and picture element drive
means connected to the sets of address conductors for applying
drive voltages to the picture elements comprising a scanning
signal drive circuit for applying selection signals to the
conductors of one set and a data signal drive circuit for
applying data signals to the conductors of the other set,
characterised by the steps of deriving a control signal
indicative of the electrial current flowing in at least one
address conductor of the one set in response to the
application of selection signals to that address conductor and
controlling the level of the drive voltages applied to the
picture elements in accordance with the value of the control
signal.
We note that although method claimed 13 appears to be in
proper step-plus-function format and thus is entitled to be
Appeal No. 96-0236
Application 08/187,364
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construed in accordance with 35 U.S.C. § 112 ¶ 6, O.I. Corp.
v.
Tekmar Co., 115 F.3d 1576, 1582-83, 42 USPQ2d 1777, 1781-82
(Fed.
Cir. 1997), Appellant does not rely on § 112 ¶ 6 to
distinguish
this claim from the prior art.
The references relied on by the examiner in the Answer
are:
Hoshino 3-146,992 (Japan) June 21, 1991
Kuijk 0,362,939 (EPO) April 11, 1990
Fuse 3-200,214 (Japan) Sept. 2, 1991
When the final Office action and the Answer were
prepared, the only portions of Hoshino and Fuse that had
English-language translations were the abstracts. The PTO-892
mailed with the Supplemental Examiner's Answer additionally
lists an English-language translation of the entire Hoshino
reference and Fuse U.S. patent 5,229,761, which the examiner
characterizes as corresponding to the Fuse Japanese reference
(Supplemental Examiner's Answer at 8). In response to
Appeal No. 96-0236
Application 08/187,364
- 5 -
Appellant's complaint (Supplemental Reply Brief at 1) that a
copy of the Hoshino translation did not accompany the
Supplemental Examiner's Answer, a copy was sent to Appellant
(paper No. 20), who did not file a response. With respect to
Hoshino, we will rely on the English-language abstract and
full translation. However, we will not rely on the Fuse U.S.
patent, because it is not cited in the statement of the
rejection, as is necessary for it to be considered in
connection with the rejection. In re Hoch, 428 F.2d 1341,
1342 n.3, 166 USPQ 406, 407 n.3 (CCPA 1970). Furthermore, it
does not directly correspond to the Fuse Japanese patent and
thus cannot be considered to be an English-language
translation thereof (e.g., Fuse U.S. has twelve figures; Fuse
Japan has only seven). Fuse U.S. apparently combines the
disclosures of the Fuse Japanese reference and another Fuse
Japanese application, both of which are identified in Fuse
U.S. as priority applications.
Claims 1, 2, 4, 9-14, and 16 stand rejected under 35
U.S.C. § 103 as unpatentable over Hoshino in view of Kuijk.
Claims 3 and 5 stand rejected under § 103 as unpatentable over
Hoshino in view of Kuijk and Fuse.
Appeal No. 96-0236
Application 08/187,364
- 6 -
Hoshino discloses voltage control circuitry for
controlling contrast in a liquid crystal display device as a
function of the drive frequency of the individual elements of
the display device (Abstract; Transl. p. 3, last sentence).
Referring to Figure 3, individual picture elements are
selected for activation by a scanning side drive circuit 7 and
a signal side drive circuit 6 (Transl. at 5, lines 23-25).
Figures 4(b) and 4(c) show examples of scanning side drive
voltages and signal side voltages, respectively, which have
voltage levels V -V . Figure 4(a) shows the difference between1 6
these two voltages, which is the differential drive signal
across the display elements. In this differential drive
signal, voltage levels V and -V are selection voltages, Vs s n
and -V are non-selection voltages, and V and -V are biasn b b
voltages (Transl. p. 5, lines 20-21). Referring to Figure 6:
waveform FLM is a frame signal; waveform CL is a dot clock
signal; waveform V is a differential drive signal in whichA
the drive frequency is the lowest; and waveform V is aB
differential drive signal in which the drive frequency is the
highest (Transl. p. 7, line 23 to p. 8, line 3). Figure 7
shows the differential voltage needed to achieve maximum
Appeal No. 96-0236
Application 08/187,364
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contrast as a function of drive frequency (Transl p. 8, lines
4-19).
Referring to Figure 1 and to pages 16-17 of the translation, a
drive frequency detection circuit 9A detects the frequency of
the liquid crystal drive voltage from data signals DA and
control signals CS and generates a voltage control signal CV,
which is used to control the voltages V -V . In Figure 10, the1 6
data signal D takes the form of a two-level signal, which we
presume represents selection and non-selection states (Transl.
p. 12, lines 13-14). The drive frequency is obtained by
measuring the frequency of the status variations between
selection and non-selection states at each signal electrode,
i.e., at each electrode of the signal side drive circuit 6
(Transl. p. 13, line 7 to p. 14, line 9). Figure 12 shows an
example of circuitry for deriving voltage control signal CV
from a plurality of signal electrode data signals D -D . Thisa e
circuitry includes respective counters C -C for obtaininga e
counts K -K of the status variations in the signal electrodea e
data signals, an addition circuit 10 for obtaining the sum of
counts K -K , and a voltage control signal conversion circuita e
Appeal No. 96-0236
Application 08/187,364
The name of this circuit is given in the translation at3
p. 36, under the heading "Figure 12."
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11 responsive to this sum and to control signals CS for3
generating control voltage CV (Transl. p. 18, line 15 to p.
19, line 8).
Regarding claim 1, the examiner correctly notes that
Hoshino fails to disclose using a picture element in the form
of a display element connected in series with a two-terminal
non-linear device (Suppl. Answer at 3, lines 10-11). To cure
this deficiency, the examiner relies on Kuijk, which discloses
a matrix display device wherein each picture element includes
a liquid crystal pixel element 12 connected in series with a
non-linear switching element 15, which may be of the MIM type
(Fig. 1a; p. 3, lines 6-9). Appellant does not challenge the
examiner's conclusion that it would have been obvious in view
of Kuijk to implement each of Hoshino's picture elements as a
non-linear switching element in series with a liquid crystal
pixel element. Instead, Appellant challenges the examiner's
following argument regarding the requirement of the claim for
"a sensing circuit . . . arranged to provide a control signal
indicative of electrical current flowing in at least one
Appeal No. 96-0236
Application 08/187,364
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address conductor . . . in response to the application of
selection signals to that address conductor" (our emphasis):
As to claims 1 and 13, it would have been obvious to
have the control signal (CV) [in Hoshino] to indicate
electrical current flowing in at least one address
conductor in response to the selection signals (V ) toLCD
the address conductor since Hoshino applies the signals
(V )to drive a display(1) (see Hoshino’s figures 1,4;LCD
page 5, lines 15-26; page 6 and page 7, lines 1-5) and
Kuijk teaches the current will flow into an address
conductor and a data conductor when a driving voltage is
applied to the matrix display (see Kuijk's figure 3 and
page 3, lines 2-3)[which state that Figure 3 shows the
current-voltage characteristic for the non-linear
switching device]. [Suppl. Answer at 3-4.]
Despite the use of the term "obvious," it is apparent from the
foregoing argument, the lack of any suggestion in Kuijk to
measure current, and the examiner's failure to proposed any
further structural modification of Hoshino that the examiner's
actual position is that Hoshino as modified to employ Kuijk's
non-linear switching elements inherently will satisfy the
claim limitation in question, i.e., that detected frequency of
the status variations in the signal electrode data signals
inherently will be "indicative of" the current flowing in at
least one of the display elements.
Appellant challenges the rejection on several grounds,
the first being that Hoshino and Kuijk collectively fail to
Appeal No. 96-0236
Application 08/187,364
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address the problem of changes in the voltage-current
characteristics due to aging. This argument is unconvincing
because the claims do not require that the voltage control
signal provide compensation for this particular problem and
the references need not be combined to solve the particular
problem addressed in Appellant's disclosure. In re Beattie,
974 F.2d 1309, 1312, 24 USPQ2d 1040, 1042 (Fed. Cir. 1992).
Appellant also argues that while Hoshino as modified to
employ Kuijk's non-linear switching elements develops a
voltage control signal (CV) that is used to adjust the drive
voltages, the voltage control signal is not "indicative of"
the current in at least one address conductor (i.e., at least
one display element). We agree, because the frequency of the
status variations in the signal electrode data signals, which
frequency is detected and used to generate the voltage control
signal,
has no fixed relationship to the amount of current flowing in
the display elements. Instead, average current is a function
of the frequency and duration of the selection pulses. Thus,
a given frequency of short-duration selection pulses will
provide less average current than the same frequency of long-
Appeal No. 96-0236
Application 08/187,364
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duration selection pulses. In fact, it is possible for low-
frequency pulses of long duration to produce a higher average
current than is produced by high-frequency pulses of short
duration.
For the foregoing reason, the rejection of independent
claims 1 and 13 for unpatentability over Hoshino in view of
Kuijk is reversed, as is the rejection of dependent claims 2,
4, 9-12, 14, and 16 over those two references.
The above-noted deficiency in the teachings of Hoshino
and Kuijk is not cured by Fuse, on which the examiner
additionally relies in rejecting claims 3 and 5.
Consequently, the rejection of these claims over Hoshino in
view of Kuijk and Fuse is also reversed.
REVERSED
)
JOHN C. MARTIN )
Administrative Patent Judge )
)
)
) BOARD OF PATENT
RICHARD L. TORCZON, JR. )
Administrative Patent Judge ) APPEALS AND
)
Appeal No. 96-0236
Application 08/187,364
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) INTERFERENCES
)
JAMES T. CARMICHAEL )
Administrative Patent Judge )
DYM
Appeal No. 96-0236
Application 08/187,364
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Corporate Patent Counsel
U.S. Philips Corporation
Patent Dept.
580 White Plains Rd.
Tarrytown, NY 10591