Solas OLED Ltd.

Patent Trials and Appeals Board

Mar 31, 2021

IPR2020-00140 (P.T.A.B. Mar. 31, 2021)

Trials@uspto.gov Paper 48
571-272-7822 Entered: March 31, 2021

UNITED STATES PATENT AND TRADEMARK OFFICE
____________

BEFORE THE PATENT TRIAL AND APPEAL BOARD
____________

SAMSUNG DISPLAY CO., LTD.,
Petitioner,

v.

SOLAS OLED LTD.,
Patent Owner.
____________

IPR2020-00140
Patent 6,072,450
____________

Before SALLY C. MEDLEY, JESSICA C. KAISER, and
JULIA HEANEY, Administrative Patent Judges.

HEANEY, Administrative Patent Judge.

JUDGMENT
Final Written Decision
Determining All Challenged Claims Unpatentable
37 C.F.R. § 318(a)

I. INTRODUCTION
Samsung Display Co., Ltd. (“Petitioner”)1 filed a Petition to institute
an inter partes review of claims 1–9, 11–13, and 15–18 of U.S. Patent

1 This proceeding has been terminated with respect to one of the original
petitioners, Dell Inc., and a petitioner by joinder, Apple Inc. See Paper 46.
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No. 6,072,450 (Ex. 1001, “the ’450 patent”). Paper 1 (“Petition” or “Pet.”).
Solas OLED Ltd. (“Patent Owner”) filed a Preliminary Response. Paper 7
(“Prelim. Resp.”). Taking into account the arguments presented in Patent
Owner’s Preliminary Response, we determined the information presented in
the Petition established that there was a reasonable likelihood that Petitioner
would prevail in challenging at least one of claims 1–9, 11–13, and 15–18 of
the ’450 patent, and we instituted this inter partes review as to all challenged
claims. Paper 9 (“Dec. on Inst.”).
During the course of trial, Patent Owner filed a Patent Owner
Response (Paper 20, “PO Resp.”); Petitioner filed a Reply to the Patent
Owner Response (Paper 26, “Pet. Reply”); Patent Owner filed a Sur-reply
(Paper 28, “PO Sur-reply”). An oral hearing was held on February 9, 2021,
and a transcript of the hearing is included in the record. Paper 43 (“Tr.”).
We have jurisdiction under 35 U.S.C. § 6. This decision is a Final
Written Decision under 35 U.S.C. § 318(a) as to the patentability of claims
1–9, 11–13, and 15–18 of the ’450 patent. For the reasons discussed below,
we hold that Petitioner has demonstrated by a preponderance of the evidence
that claims 1–9, 11–13, and 15–18 are unpatentable under § 103.
II. BACKGROUND
A. The ’450 Patent (Ex. 1001)
The ’450 patent, titled “Display Apparatus,” describes a passive
matrix type electroluminescent (“EL”) display apparatus including parallel
cathode lines, parallel anode lines perpendicular to the cathode lines, and an
organic electroluminescent layer between the cathode lines and anode lines.
Ex. 1001, [54], 1:6–7, 1:14–20. Applying a positive voltage to the cathode
lines drives the organic electroluminescent layer, and the display apparatus
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displays an image corresponding to the applied voltage. Id. at 1:20–24. The
’450 patent explains that the organic electroluminescent layer “can emit light
at a high instantaneous luminance by applying a high voltage to the organic
EL layer” but, due to this, “the organic EL layer can easily deteriorate.” Id.
at 1:38–41. The ’450 patent further explains that the larger the number of
anode lines and cathode lines, the greater the possibility of crosstalk in a
passive matrix type electroluminescent display apparatus, which makes it
difficult to display a highly precise image. Id. at 1:42–46.
The ’450 patent describes a conventional active matrix type display
apparatus to address the above problems. Id. at 1:47–49. The display
apparatus is depicted in Figure 22 of the ’450 patent, reproduced below.

Figure 22 “is a plan view of a display apparatus according to the related art.”
Id. at 5:12–13. The display apparatus includes pairs of thin film transistors
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that include selection transistor T1 and drive transistor T2 and confer a
voltage storing capability on pixels. Id. at 1:49–51. The ’450 patent states
that transistors T1, T2 can be thin film transistors. Id. at 1:58–59.
The display apparatus further includes an organic EL layer 106 that is
arranged to not overlap transistors T1 and T2 so that light emitted by the EL
layer 106 is prevented from entering thin film transistors T1, T2. Id. at
2:23–27. The ’450 patent explains that “[i]f the emitted light entered the
thin film transistors T1 and T2, unnecessary photoelectromotive force would
be generated in the channel regions of the thin film transistors T1 and T2,
which entails the possibility of the thin film transistors T1 and T2
malfunctioning.” Id. at 2:27–32.
An object of the ’450 patent is “to provide a display apparatus which
has a light emitting area enlarged so as to emit light at a satisfactorily high
luminescence even though a voltage applied to an EL layer is low, and
which has a long luminance life.” Id. at 2:66–3:3. Another object of the
’450 patent is “to provide a display apparatus which prevents light from
entering active elements such as transistors, to thereby avoid the malfunction
of the active elements.” Id. at 3:4–7. An embodiment of such a display
apparatus is shown in Figure 1, which is reproduced below.
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Figure 1 “is a plan view of an [sic] display apparatus according to one
embodiment of the present invention.” Id. at 4:28–29.
The ’450 patent states that display apparatus 1 includes “a substrate 2,
an n-channel transistor Q1, an n-channel transistor Q2, [and] an organic EL
element 3.” Id. at 5:25–33. According to the ’450 patent, “[i]n the entire
display area, an organic EL layer 16 is formed on the cathode electrodes 15
and the interlayer insulation film 14, and a transparent anode electrode 17.”
Id. at 6:39–41. The ’450 patent further explains that “each EL element 3
emits light over the entirety of one pixel area” and “cathode electrodes 15
are formed of MgIn which reflects light.” Id. at 7:66–8:47, 8:49–50. Thus,
“light emitted by the organic EL layer 16 when a voltage is applied between
the anode electrode 17 and the cathode electrodes 15 comes out through the
anode electrode 17 without leaking downward” and “the light does not enter
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the selection transistors Q1 and the drive transistors Q2, and hence the
malfunction of the transistors Q1 and Q2 due to the photoelectromotive
force is avoided.” Id. at 8:50–57.
In addition, the ’450 patent describes wavelength conversion layers
having the photoluminescence effect of absorbing light of one wavelength
from an organic electroluminescence layer and emitting light of a different
wavelength. Id. at 11:47–65. As a result, “display apparatus 1 can easily
display a full-color image.” Id. at 12:8–9. The ’450 patent also describes
color filter layers that allow light of only a certain wavelength range to pass
through. Id. at 12:28–48. In one embodiment, a color filter absorbs a
wavelength range of light that excites a corresponding wavelength
conversion layer so the wavelength conversion layer is not excited by light
coming from outside of the display apparatus. Id. at 12:49–13:10. The ’450
patent explains that with such an arrangement of wavelength range
conversion layers and color filter layers, “the color purity of light going
outside the display apparatus 1 is high.” Id. at 13:17–18.
B. The Challenged Claims
Petitioner challenges claims 1–9, 11–13, and 15–18 of the ’450 patent.
Pet. 1. Claims 2–9, 11–13, 17, and 18 depend from claim 1, and claim 16
depends from claim 15. Claim 1, reproduced below, is illustrative of the
subject matter of the challenged claims:
1. A display apparatus comprising:
a substrate;
active elements formed over said substrate and driven by an
externally supplied signal;
an insulation film formed over said substrate so as to cover said
active elements, said insulation having at least one contact hole;
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at least one first electrode formed on said insulation film so as
to cover said active elements, and connected to said active
elements through said at least one contact hole, said at least one
first electrode being made of a material which shields visible
light;
an organic electroluminescent layer having an organic
electroluminescent material formed on said at least one first
electrode so as to cover said active elements and including at
least one layer which emits light in accordance with a voltage
applied to said at least one layer; and
at least one second electrode formed on said organic
electroluminescent layer which covers said active elements.
Ex. 1001, 17:49–18:3.
C. Asserted Grounds of Unpatentability
Petitioner asserts the following grounds of unpatentability:
Challenged Claim(s) 35 U.S.C.2 Reference(s)/Basis
1, 2, 4–8, 15, and 16 § 102(e) Utsugi3
1, 2, 4–8, 15, and 16 § 103(a) Utsugi
3 § 103(a) Utsugi and Manabe4
9, 11–13, 17, and 18 § 103(a) Utsugi and Eida5

2 The Leahy-Smith America Invents Act (“AIA”) included revisions to 35
U.S.C. §§ 102 and 103 that became effective on March 16, 2013. Because
the ’450 patent issued from an application filed before March 16, 2013, we
apply the pre-AIA versions of the statutory bases for unpatentability.
3 US Patent No. 5,670,792 to Utsugi et al., issued Sept. 23, 1997 (Ex. 1003).
4 JP H05-3079 to Manabe et al. Citations to Manabe reference Petitioner’s
certified translation of Manabe (Ex. 1004), unless stated otherwise. A
Japanese language copy of Manabe was provided as Exhibit 1009.
5 WO 96/25020 to Eida et al. Citations to the Eida reference are to
Petitioner’s certified translation of Eida (Ex. 1005), unless stated otherwise.
A Japanese language copy of Eida was provided as Exhibit 1010.
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Pet. 5. Petitioner relies on testimony of Adam Fontecchio, Ph.D. (Ex. 1007)
(“Fontecchio Declaration”). Patent Owner relies on testimony of Richard
Flasck (Ex. 2001) (“Flasck Declaration”).
D. Related Proceedings
The parties identify the following litigation involving the ’450 patent:
Solas OLED Ltd. v. Samsung Display Co., Ltd., et al., No. 2:19-cv-00152-
JRG (E.D. Tex.); Solas OLED Ltd. v. Dell Technologies Inc., No. 6:19-cv-
00514-ADA (W.D. Tex.); Solas OLED Ltd. v. Google Inc., No. 6:19-cv-
00515-ADA (W.D. Tex.); and Solas OLED Ltd. v. Apple Inc., No. 6:19-cv-
00537-ADA (W.D. Tex.). Pet. 4; Paper 5, 1. The parties have informed us
that there has been a jury verdict in the Eastern District of Texas proceeding.
Ex. 1019, 7:3–11, 7:21–8:3, 9:11–13. In that verdict, the jury determined
claims 4 and 5 were invalid, and did not address the other claims challenged
in this proceeding. Id.
III. ANALYSIS
A. Claim Construction
In an inter partes review, we construe claim terms according to the
standard set forth in Phillips v. AWH Corp., 415 F.3d 1303, 1312–17 (Fed.
Cir. 2005) (en banc). 37 C.F.R. § 42.100(b) (2019). Under that standard,
we construe claims “in accordance with the ordinary and customary meaning
of such claim as understood by one of ordinary skill in the art and the
prosecution history pertaining to the patent.” Id. Furthermore, we expressly
construe the claims only to the extent necessary to resolve the parties’
dispute. See Nidec Motor Corp. v. Zhongshan Broad Ocean Motor Co. Ltd.,
868 F.3d 1013, 1017 (Fed. Cir. 2017) (“[W]e need only construe terms ‘that
are in controversy, and only to the extent necessary to resolve the
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controversy’ . . . .” (quoting Vivid Techs., Inc. v. Am. Sci. & Eng’g, Inc., 200
F.3d 795, 803 (Fed. Cir. 1999))).
In our Decision on Institution, we determined that we did not need to
explicitly construe any claim terms at that stage of the proceeding. Dec. on
Inst. 8. After the Petition was filed, the parties agreed on constructions for
the claim terms “active elements” and “wherein said at least one first
electrode has a rough surface which is in contact with the said organic
electroluminescent layer” in Case No. 2:19-cv-00152-JRG (E.D. Tex.), and
the district court in that case adopted the parties’ construction of “cover” and
resolved the parties’ dispute as to whether the term “said active elements”
necessarily mapped onto all active elements in a device. PO Resp. 8–9
(citing Ex. 1012, Ex. 2006); Pet. Reply 2 (citing Ex. 1012, Ex. 2006).
Moreover, during the instant trial, the parties agreed that we do not need to
resolve any claim construction issues in order to resolve the challenges
raised in the Petition. See PO Resp. 9; Pet. Reply 2–3.
We determine that we need not explicitly construe any claim terms to
resolve the unpatentability issues before us. See Nidec, 868 F.3d at 1017
(“[W]e need only construe terms ‘that are in controversy, and only to the
extent necessary to resolve the controversy’ . . . .” (quoting Vivid Techs., 200
F.3d at 803)).
B. Level of Ordinary Skill in the Art
Factors pertinent to a determination of the level of ordinary skill in the
art include “(1) educational level of the inventor; (2) type of problems
encountered in the art; (3) prior art solutions to those problems; (4) rapidity
with which innovations are made; (5) sophistication of the technology; and
(6) educational level of workers active in the field.” Envtl. Designs, Ltd. v.
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Union Oil Co., 713 F.2d 693, 696–97 (Fed. Cir. 1983) (citing Orthopedic
Equip. Co. v. All Orthopedic Appliances, Inc., 707 F.2d 1376, 1381–82 (Fed.
Cir. 1983)). Not all such factors may be present in every case, and one or
more of these or other factors may predominate in a particular case. Id.
In our Institution Decision, we adopted Petitioner’s formulation of the
level of ordinary skill in the art and determined that a person of ordinary
skill in the art at the time of the invention “would have had a relevant
technical degree in Electrical Engineering, Computer Engineering, Materials
Science, Physics, or the like, and experience in active matrix display design
and electroluminescence.” Dec. on Inst. 9 (quoting Pet. 13) (adopting
Petitioner’s formulation, which is supported by Dr. Fontecchio’s testimony,
because it is consistent with the ’450 patent and the asserted prior art). In its
Patent Owner Response, Patent Owner argues that a person of ordinary skill
would need approximately two years of experience working in design and
development related to active matrix organic light emitting diodes
(“OLED”) displays, in addition to a Bachelor’s degree in Electrical
Engineering, Physics, and/or Materials Science and Engineering or
equivalent training. PO Resp. 7–8 (citing Ex. 2001 ¶¶ 30–31). Patent
Owner also states, however, that its arguments in opposition to the Petition
apply under Petitioner’s definition of the level of ordinary skill as well. Id.
at 8. Accordingly, having considered the parties’ arguments and evidence,
we maintain our determination from the Institution Decision adopting
Petitioner’s proposed level of ordinary skill in the art, as it is consistent with
the problems and solutions in the ’450 patent and prior art of record. We
also determine our decision would be the same under either side’s
formulation of the level of ordinary skill.
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C. Principles of Law
A claim is unpatentable under 35 U.S.C. § 103 if “the differences
between the subject matter sought to be patented and the prior art are such
that the subject matter as a whole would have been obvious at the time the
invention was made to a person having ordinary skill in the art to which said
subject matter pertains.” KSR Int’l Co. v. Teleflex, Inc., 550 U.S. 398, 406
(2007). The question of obviousness is resolved on the basis of underlying
factual determinations, including (1) the scope and content of the prior art;
(2) any differences between the claimed subject matter and the prior art;
(3) the level of ordinary skill in the art; and (4) when available, evidence
such as commercial success, long felt but unsolved needs, and failure of
others. Graham v. John Deere Co., 383 U.S. 1, 17–18 (1966); see KSR, 550
U.S. at 407 (“While the sequence of these questions might be reordered in
any particular case, the [Graham] factors continue to define the inquiry that
controls.”).
The Supreme Court made clear that we apply “an expansive and
flexible approach” to the question of obviousness. KSR, 550 U.S. at 415.
Whether a patent claiming the combination of prior art elements would have
been obvious is determined by whether the improvement is more than the
predictable use of prior art elements according to their established functions.
Id. at 417. Reaching this conclusion, however, requires more than merely
showing that the prior art includes separate references covering each
separate limitation in a challenged claim. Unigene Labs., Inc. v. Apotex,
Inc., 655 F.3d 1352, 1360 (Fed. Cir. 2011). Rather, obviousness
additionally requires that a person of ordinary skill at the time of the
invention “would have selected and combined those prior art elements in the
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normal course of research and development to yield the claimed invention.”
Id.
D. Overview of the Asserted References
1. Utsugi (Ex. 1003)
Utsugi is titled “Current-Controlled Luminous Element Array and
Method for Producing the Same” and relates “to a current-controlled
luminous element array of an active matrix type such as for a display
purpose, having multiple current-controlled luminous elements arranged in a
matrix form.” Ex. 1003 at [54], 1:8–11. Utsugi’s Figure 5 is reproduced
below.

Utsugi’s Figure 5 is a sectional view of an internal structure of a picture
element, according to an embodiment of Utsugi. Id. at 5:39–41. The picture
element includes a luminescent element EL that “includes an organic thin-
film layer 52 of a three-layered structure having a spacer layer 52C, an
organic luminescent layer 528 and a hole injection layer 52A laminated in
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this order over a glass base 50.” Id. at 6:37–41. Utsugi’s device further
includes electron injection electrode 55. Id. at 6:47–54.
Utsugi describes “[t]he luminescent element EL as a layered organic
thin-film EL element extends over the capacitor C and the transistors QI and
QS, covering substantially the entirety of the picture element region.” Id. at
6:23–27.
2. Manabe (Ex. 1004)
Manabe is titled “Organic EL Element.” Ex. 1004 at [54]. Manabe’s
Figure 1 is reproduced below.

Figure 1 “is a drawing showing an embodiment applying the present
invention to an organic EL element with a two-layer structure.” Id. ¶ 34.
Manabe describes an organic electroluminescent element that includes
transparent electrode 2 and hole transport layer 4 that make up an organic
electroluminescent layer, light emitting layer 3, and metal electrode 1
“formed in order on the rough surface of a glass substrate 6.” Id. ¶ 26.
Manabe’s Figure 5 is reproduced below.
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Figure 5 “is a partial enlarged cross-section drawing describing light
interference of an organic EL element with a two-layer structure.” Id. ¶ 34.
Manabe explains:
Light emitted from one point of emission source P within the EL
layer includes light from two sources, path A of light directly
impinging on the substrate 6 in the drawings and path B of light
reflecting off the metal electrode 1 and impinging on the
substrate 6. The light from these two paths have light path
difference L given by equation 1 and furthermore phase
difference ηy given by equation 2 and mutually interfere.
Id. ¶ 7. In view of this, Manabe describes:
roughening of the surface of the organic EL layer in contact with
the metal electrode or the surface of the metal electrode in
contact with the organic EL layer causes slight differences in the
light path from light sources within the light emission layer
causing averaging of the interference effect and reducing angle
dependence and film thickness dependence.
Id. ¶ 24.
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In addition, Manabe states:
In this manner, the interface of each layer is roughened to a
degree as described above. As a result, there are different optical
path variations from each of the light emitting points in the light
emitting layer when seen from certain visual angles and is not
constant. Therefore, interference effect is averaged, and changes
in visual angle dependence in luminance and the light emitting
spectrum and variation in membrane thickness are suppressed.
Id. ¶ 31.
3. Eida (Ex. 1005)
Eida is titled “Multi-Color Light Emission Apparatus and Method for
Production Thereof” and “relates to a multi-color light emission apparatus
suitable for use in multi-color or full-color thin-type displays and a method
for producing the multi-color light emission apparatus.” Ex. 1005 at [54],
1:6–8.
Eida’s Figure 5 is reproduced below.

Figure 5 “is a schematic cross section that schematically shows the multi-
color light emission apparatus (first invention) of the present invention with
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an example using a color filter and a black matrix.” Id. at 8:1–3. Eida
describes a multi-color light emissions apparatus that includes support
substrate 2, organic electroluminescent element 1, transparent inorganic
oxide substrate 4, fluorescent layers 3, and transparent substrate 8. Id. at
9:22–24, 9:28–10:5.
According to Eida, “a fluorescent layer should convert the light
emitted from an organic EL element into light of a wave length longer than
that of the light emitted from the organic EL element,” and fluorescent
layers 3 “emit rays of fluorescent light of different colors . . . separately
arranged on the same plane to obtain emitted light of the three primary
colors (RGB).” Id. at 9:24–26, 10:12–13. Eida states that “[t]he installation
of the fluorescent layer has the advantage that multi-color light emission
which is higher in efficiency than in the case of installing a color filter can
be anticipated.” Id. at 3:8–9. Eida further describes that “a color filter 9a
may be arranged on each of the fluorescent layers 3 to control the
fluorescent colors and thereby to promote the color purity.” Id. at 10:15–16.
Eida depicts another embodiment in Figure 13, reproduced below.
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Figure 13 “is a schematic cross section that schematically shows the multi-
color light emission apparatus (second invention) of the present invention
showing another embodiment that uses a transparent adhesive, transparent
fluorescent layer protective layer, color filter, and a black matrix.” Id. at
8:31–9:2. The multi-color light emission apparatus includes a transparent
support substrate (not labeled in Figure 13), red color conversion fluorescent
layer 3R, green color conversion fluorescent layer 3G, blue color filter 14,
transparent and electrically insulating inorganic oxide layer 12, and organic
electroluminescent element 1. Id. at 37:11–38:2, 38:10–12.
Eida explains that blue color filter 14 adjusts “the colors of light
emitted from the organic EL element to improve the purity of these colors.”
Id. at 38:10–12. Eida further explains that, in addition to the above
structures, “a red color filter and a green color filter may be arranged
between the red color conversion fluorescent layer 3R and the transparent
substrate, and between the green color conversion fluorescent layer 3G and
the transparent substrate respectively, thereby adjusting colors of light of a
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red color and of a green color to improve purity of these colors.” Id. at
38:4–8.
E. Alleged Obviousness Based on Utsugi
Petitioner argues that claims 1, 2, 4–8, 15, and 16 would have been
obvious over Utsugi. Pet. 53–62. We have reviewed the evidence and
arguments provided by the parties and are persuaded, based on the record
before us, that Petitioner has demonstrated by a preponderance of the
evidence that claims 1, 2, 4–8, 15, and 16 would have been obvious over
Utsugi.
Claim 1
“a substrate”
“active elements formed over said substrate and driven by
an externally supplied signal”
Petitioner contends that Utsugi discloses these limitations because
“glass base 50” is a substrate upon which the EL element is built (Pet. 22
(citing Ex. 1003, 6:37–40; Ex. 1007 ¶ 75)), and current-controlling transistor
QI and switching transistor QS are active elements formed on top of glass
base 50. Pet. 22–23 (citing Ex. 1003, 6:19–23, 7:20–45, Fig. 5; Ex. 1007
¶¶ 77–78). Petitioner also contends that switching transistor QS is driven by
the external signal from scan electrode line 3N+1, while current-controlling
transistor QI is driven by the external signal from the signal electrode line
1M. Id. at 23 (citing Ex. 1003, 7:9–12, 8:11–16, Fig. 3; Ex. 1007 ¶ 79).
Patent Owner does not present any argument with respect to these
limitations. Based on the evidence presented, we are persuaded that Utsugi
teaches these limitations.
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“an insulation film formed over said substrate so as to cover
said active elements”
Petitioner contends Utsugi discloses an SiO2 layer covering transistor
QI, and contact hole 56B formed in the SiO2 layer so as to allow contact
between electron injection electrode 55 and drain electrode DQI of QI. Pet.
24 (citing Ex. 1003, Fig. 5, 7:46–51; Ex. 1007 ¶ 83). Petitioner provides an
annotated version of Utsugi’s Figure 5, reproduced below.

Figure 5 is a sectional view of an internal structure of a picture element
according to Utsugi’s first embodiment; the annotated version of Figure 5
adds yellow highlighting on the upper SiO2 layer, and text stating that the
upper SiO2 layer is “formed over transistors (QI and QS) and substrate (glass
base 50).” Pet. 25. Petitioner acknowledges that transistor QS is not visible
in Figure 5, and therefore Figure 5 does not depict the insulating film
covering this transistor. Pet. Reply 4.
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Petitioner contends that it would have been obvious to form the SiO2
layer to cover QS because Utsugi’s disclosures show that the SiO2 layer is
deposited over the array after QI and QS have been formed, the purpose of
the SiO2 layer is to form an insulation layer, and a person of ordinary skill in
the art would have been motivated to leave the insulating SiO2 layer in place
above QS, just as it is above QI. Pet. Reply 9 (citing Ex. 1007 ¶¶ 168–170).
Petitioner further contends that a person of ordinary skill in the art would
have understood “that it would have been obvious, if not necessary, to
include an insulation layer” over both transistors QS and QI, in order to
prevent the metal layers of the transistors from coming into contact with
electron injection electrode 55, which would cause them to short circuit.
Pet. 53–54 (citing Ex. 1003, Fig. 4; Ex. 1007 ¶¶ 168–170). According to
Petitioner:
Using Utsugi’s SiO2 insulation layer to provide the insulation
above transistor QS would be the most natural and
straightforward implementation of Utsugi’s disclosures: it
would entail simply not undertaking an undisclosed and
unnecessary additional step of patterning or masking the SiO2
insulation to remove it from the area above transistor QS.
Pet. Reply 9–10.
Petitioner also argues that including an insulation layer over both
transistors would have been predictable and nothing more than applying a
known technique to a known device, as evidenced by the ’450 patent’s
teaching that related art at the time of the invention made use of a
passivation film that covered both transistors. Pet. 55 (citing Ex. 1007
¶ 169). Petitioner relies on the ’450 patent’s description of the related art in
Figures 22 and 23, which states that the thickness of passivation film 104 is
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set at such a value to “prevent the occurrence of a parasitic capacitance in
the thin film transistors.” Id. (citing Ex. 1001, 2:53–56).
Patent Owner contends that Utsugi’s SiO2 layer does not necessarily
cover transistor QS, because different materials or techniques could be used
in forming Utsugi’s structure, in order to insulate the electrodes of QS and QI.
PO Resp. 12–13 (citing Ex. 2001 ¶¶ 54–55). In response to Petitioner’s
rationale as to why it would have been obvious to use Utsugi’s SiO2
insulation layer to provide the insulation above transistor QS, Patent Owner
contends that the “undisclosed” and “unnecessary” masking or patterning
steps that Petitioner asserts would be avoided by modifying Utsugi are
“already present in the process disclosed in Utsugi, meaning that no
‘undisclosed’ or ‘unnecessary’ steps are required.” PO Sur-reply 5 (citing
Ex. 2001 ¶ 54).
Patent Owner further contends that Petitioner’s reliance on Figure 23
of the ’450 patent is improper hindsight because there is no evidence that
Figure 23 was actually known in the prior art. PO Resp. 13 (citing Ex. 1001,
1:47–49; Ex. 2001 ¶ 56); PO Sur-reply 6. According to Patent Owner,
insulation film 104 of Figure 23 “does not have a ‘contact hole’ as this
limitation requires,” and the Petition does not explain how a contact hole
would be formed in the insulation film or “how that contact hole could
connect the ‘first electrode’ to the ‘active elements,’ as required by the ’450
patent claims.” Id. at 13–14 (citing Ex. 2001 ¶¶ 56–57).
Based on the evidence presented, notwithstanding Patent Owner’s
arguments to the contrary as discussed above, we find Petitioner has
demonstrated by a preponderance of the evidence that a person of ordinary
skill in the art would have modified Utsugi so that the SiO2 layer covers both
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transistors QS and QI, and satisfies this limitation. We find persuasive
Petitioner’s rationale that a person of ordinary skill would have understood
that insulation above transistor QS would have been necessary to prevent a
short circuit across QS; indeed, both parties’ experts agree on this point. See
Ex. 1007 ¶ 168; Ex. 1017, 155:8–16. We also find it persuasive, as
Petitioner argues, that using the SiO2 layer to provide insulation above
transistor QS would have been straightforward and efficient, because it
would have avoided additional patterning and the SiO2 layer was already
used to provide insulation above other structures. See Ex. 1007 ¶ 169.
Patent Owner’s argument that a different insulating material could be
deposited does not undermine Petitioner’s showing because Mr. Flasck did
not articulate any reason why a person of ordinary skill would undertake
such an additional step. See Ex. 1017, 156:6–21. And Patent Owner fails to
adequately explain how Petitioner’s proposed modification does not avoid
the asserted additional patterning steps; Mr. Flasck’s testimony does not
specifically address this. See Ex. 2001 ¶ 54; see generally Ex. 1017. We
have also considered Patent Owner’s argument that modifying Utsugi by
oxidizing transistor QS’s electrode in order to insulate it would have been an
alternative modification that would not involve additional patterning steps.
See Tr. 48 (quoting Ex. 2005, 98:25–99:20). Although Dr. Fontecchio’s
testimony concerning oxidation of an aluminum surface during vacuum
chamber deposition supports Patent Owner’s argument that there would have
been alternative techniques to leaving the SiO2 layer in place in order to
insulate the electrodes of QS, it neither persuades us that a person of ordinary
skill would not have been motivated to use the already-present SiO2 layer to
insulate QS, nor outweighs Petitioner’s evidence on that issue. In other
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words, one obvious modification to a reference does not exclude the
possibility of other obvious modifications.
We find Petitioner has demonstrated by a preponderance of the
evidence that a person of ordinary skill in the art would have modified
Utsugi such that this claim limitation is satisfied.
“at least one first electrode formed on said insulation film
so as to cover said active elements, and connected to said
active elements through said at least one contact hole, said
at least one first electrode being made of a material which
shields visible light”
Petitioner contends that Utsugi discloses this limitation because
electron injection electrode 55 is formed as a MgAg layer on the SiO2 layer,
as shown in Figure 5. Pet. 26 (citing Ex. 1003, 7:47–57; Ex. 1007 ¶ 86).
Petitioner further contends that electron injection electrode is connected to
transistors QS and QI through contact hole 56B, as shown in Figure 5 and
described in Utsugi’s manufacturing steps. Id. at 27 (citing Ex. 1003, 7:46–
51; Ex. 1007 ¶ 88). Petitioner also contends that MgAg, a metallic material,
would be reflective and shield visible light from the transistors. Id. at 28
(citing Ex. 1003, 6:47–50; Ex. 1007 ¶ 89). As support, Petitioner further
points out that the ’450 patent identifies magnesium-based metals such as
MgAg and MgIn as suitable materials for forming the first electrode, which
is described as shielding visible light. Id. (citing Ex. 1001, 8:49–54, 17:26–
28).
Patent Owner does not expressly dispute Petitioner’s arguments with
respect to this limitation. Based on the evidence presented, we are
persuaded that Utsugi teaches this limitation.
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“an organic electroluminescent layer having an organic
electroluminescent material formed on said at least one first
electrode so as to cover said active elements and including
at least one layer which emits light in accordance with a
voltage applied to said at least one layer”
Petitioner contends that Utsugi discloses this limitation because
organic thin-film layer 52 includes at least one layer (52B), which emits
light in accordance with a voltage applied to the layer. Pet. 28 (citing Ex.
1003, 6:59–63, 8:20–28, Fig. 5; Ex. 1007 ¶ 92). Petitioner further contends
that Utsugi discloses that the EL structure, including organic thin-film layer
52, extends over the capacitor C and transistors QS and QI, covering the
entire picture element region. Id. at 29 (citing Ex. 1003, 6:23–29, 6:53–59;
Ex. 1007 ¶ 93).
Patent Owner does not expressly dispute Petitioner’s arguments with
respect to this limitation. Based on the evidence presented, we are
persuaded that Utsugi teaches this limitation.
“at least one second electrode formed on said organic
electroluminescent layer which covers said active
elements.”
Petitioner contends that Utsugi discloses this limitation because hole
injection electrode 54 is formed on organic thin-film layer 52, so as to cover
the entire picture element region, including transistors QS and QI. Pet. 30–31
(citing Ex. 1003, 6:23–29, 6:53–59, Fig. 5; Ex. 1007 ¶¶ 95–96).
Patent Owner does not expressly dispute Petitioner’s arguments with
respect to this limitation. Based on the evidence presented, we are
persuaded that Utsugi teaches this limitation.
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Conclusion as to Claim 1
For the reasons explained above, we conclude, on this record, that
Petitioner has shown by a preponderance of the evidence that claim 1 is
unpatentable as obvious over Utsugi.
Claim 4
Claim 4 depends from claim 1, and additionally requires that the
active elements are a selection transistor and a drive transistor that form a
pair. Ex. 1001, 18:10–18. Petitioner contends Utsugi discloses that
switching transistor QS is turned on when scan electrode line 3N+1 is selected,
and that a person of ordinary skill would understand that the scan electrode
line is an address line because it addresses a row of pixels. Pet. 31–32
(citing Ex. 1003, Fig. 3, 7:9–12, 8:11–16; Ex. 1007 ¶ 101). Petitioner
further contends Utsugi discloses that image data from electrode line 1M is
supplied from the electrode line through switching transistor QS on the gate
of current-controlling transistor QI, which controls the current, and therefore
the voltage, across the organic electroluminescent layer. Id. at 32–33 (citing
Ex. 1003, 6:59–63, 8:11–16, 8:20–28; Ex. 1007 ¶ 104–105). Petitioner
further contends Utsugi discloses that transistors QS and QI form a pair. Id.
at 33 (citing Ex. 1003, 5:50–56; Ex. 1007 ¶ 106).
Patent Owner contends that Petitioner fails to show unpatentability of
claim 4 for the same reasons Patent Owner raises for claim 1, and
specifically argues that claim 4 makes explicit that the active elements QS
and QI must be covered in order to satisfy claim 1. PO Sur-reply 7. We
address Patent Owner’s arguments as to claim 1 above. We have reviewed
the parties’ contentions and the full record and conclude that Petitioner has
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proven by a preponderance of the evidence that claim 4 would have been
obvious over Utsugi.
Claims 8 and 16
Claims 8 and 16 depend from claims 1 and 15, respectively, and
additionally require that “a constant voltage is applied to said second
electrode.” Ex. 1001, 18:52. Petitioner contends Utsugi teaches a constant
voltage is applied to hole injection electrode 54, which is connected to
power source electrode line 5, labeled as VDD in Figure 3. Pet. 40 (citing Ex.
1003, Fig 3, 6:43–47). Petitioner contends that a person of ordinary skill in
the art would have understood that VDD refers to a direct current (“DC”)
supply, which has a constant voltage. Id. (citing Ex. 1006, App. D, 387).
Petitioner further contends that Utsugi’s disclosure of an example where
power source line 5 applies a 7V voltage across the EL structure (id. (citing
Ex. 1003, 8:32–40)) conveys that power source line 5 applies a constant
voltage. Id. (citing Ex. 1007 ¶ 129). Petitioner further contends that even if
a person of ordinary skill in the art would not have understood that Utsugi
teaches constant voltage, it would have been obvious to use a constant
voltage for line VDD in Utsugi because it would have been nothing more than
selection from a limited set of known options, i.e. constant voltage or
alternating voltage. Pet. 56–58 (citing Ex. 1007 ¶¶ 171–172). Petitioner
contends that because the voltage applied to the second electrode creates
current flow through luminescent element EL, a person of ordinary skill in
the art would have understood that “constant voltage would be necessary to
keep the image displayed for the entirety of a full frame, without a flicker,
and to prevent a perceivable change in brightness.” Id. at 57 (citing Ex.
1003, 6:59–63, 8:20–28; Ex. 1007 ¶¶ 171–174).
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Patent Owner disputes that Utsugi teaches that VDD is constant. PO
Resp. 16 (citing Ex. 2001 ¶ 66). Mr. Flasck testifies that “direct current”
does not mean that current is “constant.” Ex. 2001 ¶ 61. As to Utsugi’s
reference to a 7V voltage across the EL structure, Patent Owner asserts that
a constant 7V drive voltage would require that VDD change over time. PO
Resp. 17 (citing Ex. 1007 ¶ 129; Ex. 2001 ¶ 62). Patent Owner does not
address Petitioner’s argument that a person of ordinary skill in the art would
have understood that constant voltage would be necessary to display a full
frame image without flicker or perceivable change in brightness.
Petitioner responds that Utsugi does not contain any discussion of VDD
changing, and further that Utsugi’s second embodiment is inconsistent with
VDD changing because it adds diode DI between the EL element and power
source line 5, but no such diode would be necessary if VDD could be changed
over time. Pet. Reply 15–16 (citing Ex. 1003, Fig. 6, 9:39–64).
In its Sur-reply, Patent Owner further contends that Utsugi’s
description of the 7V drive voltage does not imply that it is constant, even
under Petitioner’s interpretation of Utsugi, and therefore Utsugi’s VDD is not
constant either. PO Sur-reply 16 (citing Ex. 1003, 8:32–36). Patent Owner
also contends that a person of ordinary skill in the art would have understood
that Utsugi does not include only two options for the voltage applied to the
second electrode, i.e., constant voltage or alternating voltage conditions, as
there is “at least one further possibility . . . : a ‘direct current’ that is not
constant” because the 7V voltage changes as the scan electrode line voltage
changes. Id.
We have considered the parties’ argument and evidence on this issue
as detailed above, and we find Petitioner’s contentions persuasive. As an
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initial matter, we agree with Petitioner that Utsugi’s disclosure of applying a
specific drive voltage of 7V teaches a constant voltage. Ex. 1007 ¶ 129.
Further, Petitioner has provided a persuasive explanation as to why a person
of ordinary skill in the art would have understood that Utsugi teaches
applying a constant voltage, i.e., because constant voltage would be
necessary to prevent a change in brightness in luminescent element EL. Ex.
1007 ¶¶ 171–174. Petitioner provides a rationale for a person of ordinary
skill to modify Utsugi if necessary to select constant voltage, because a
person of ordinary skill in the art would understand that constant voltage
would be most appropriate for driving Utsugi’s display without flicker or a
perceptible change in brightness. See Ex. 1007 ¶ 171. Patent Owner does
not address this evidence. Accordingly, we conclude that Petitioner has
proven by a preponderance of the evidence that claims 8 and 16 would have
been obvious over Utsugi.
Claim 15
Petitioner contends independent claim 15 is unpatentable as obvious
over Utsugi. Pet. 41–53, 58–62; Pet. Reply 19–21, 23–24. Petitioner’s
argument and evidence in support of unpatentability of claim 15 is similar to
that for claim 1, as discussed above, except that Petitioner contends Utsugi’s
switching transistor QS corresponds to claim 15’s “selection transistors
formed over said substrate arranged in a matrix pattern” and Utsugi’s
current-controlling transistor QI corresponds to claim 15’s “drive transistors
formed over said substrate . . . , each of said drive transistors being
connected to one of said selection transistors.” Pet. 42 (citing Ex. 1003, 4:5–
21, 6:19–23, 7:20–45; Ex. 1007 ¶¶ 135, 137). As to claim 15’s limitations
reciting “address lines connected to said selection transistors” and “data
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lines connected to said selection transistors,” Petitioner contends Utsugi’s
scan electrode lines correspond to the claimed address lines, and Utsugi’s
signal electrode lines correspond to the claimed data lines. Id. at 43–45
(citing Ex. 1003, Fig. 3, 3:66–4:4, 7:9–12, 8:11–16; Ex. 1007 ¶¶ 139, 141–
142). Petitioner provides an annotated version of Utsugi’s Figure 3,
reproduced below.

Figure 3 is a partial circuit diagram of an array according to Utsugi’s first
embodiment; the annotated version of Figure 3 adds highlighting and text
identifying switching transistor, current-controlling transistor, charge
holding capacitor, and organic thin-film EL elements described in Utsugi.
Pet. 44–45.
As to claim 15’s limitations that Petitioner refers to as 15[g]–[i],
Petitioner provides contentions based on Utsugi’s Figures 4 and 5 that are
substantially the same as Petitioner’s contentions for the limitations of claim
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1 relating to a first electrode, second electrode, and organic
electroluminescent layer, as discussed supra. Pet. 47–52.
We have reviewed Petitioner’s evidence and argument as to the
limitations of claim 15 discussed above, and find that Petitioner has shown
that Utsugi teaches each of these limitations. Patent Owner does not
separately address Petitioner’s showing as to these limitations of claim 15.
See generally PO Resp.; PO Sur-reply. We discuss below the limitations of
claim 15 that the parties separately address.
“an insulation film formed over said substrate so as to cover
said drive transistors, said address lines and said data lines,
said insulation film having contact holes formed in
correspondence with said drive transistors”
Petitioner contends Utsugi discloses that after current-controlling
transistor QI, scan electrode lines 3N, and signal electrode lines 1M are
formed on the substrate, SiO2 layer is grown and covers them, and then
contact holes are formed to allow contact between electron injection
electrode 55 and drain electrode DQI of current-controlling transistor QI. Pet.
46–47 (citing Ex. 1003, 7:16–52; Ex. 1007 ¶¶ 146–148). Similar to its
argument for claim 1, Petitioner contends a person of ordinary skill in the art
would have understood the SiO2 layer is continuous apart from the contact
holes (id. at 47 (citing Ex. 1003, Fig. 5; Ex. 1007 ¶ 147)), and that even if
Utsugi does not disclose that the SiO2 layer covers the scan electrode line, it
would have been obvious to leave the SiO2 layer in place above the scan
electrode line in the same way as it is left in place above the capacitor and
gate electrodes, in order to avoid an unnecessary and additional step of
patterning or masking the SiO2 layer. Id. at 58–59 (citing Ex. 1003, 7:20–
25, 46–51; Ex. 1007 ¶ 176). Petitioner further contends a person of ordinary
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skill in the art would have recognized that “it would be most efficient to
form the SiO2 layer across the entire area, so as to cover the scan electrode
lines.” Pet. Reply 20 (citing Ex. 1017, 155:20–22).
Petitioner further contends a person of ordinary skill in the art would
have understood that insulation provided by the SiO2 layer would be
beneficial to mitigate parasitic capacitance, and that the ’450 patent
recognizes parasitic capacitance as a “detrimental or unwanted
phenomenon.” Pet. Reply 21 (quoting Ex. 1001, 2:54–57; citing Ex. 1017,
174:22–175:4, 181:21–182:3).
Patent Owner responds, similar to its response for claim 1, that even if
the SiO2 layer were deposited over the scan electrode lines, it may be
removed by etching, for example as part of the same etching step used to
form second contact hole 56B. PO Resp. 19 (citing Ex. 1007 ¶¶ 84, 147;
Ex. 2001 ¶ 66). Patent Owner also contends that there would have been no
concern of shorting, unlike for claim 1, because the scan electrode lines and
electron injection electrode 55 do not overlap. Id. at 19–20 (citing Ex. 1003,
Fig. 4; Ex. 2001 ¶ 67). Patent Owner further asserts that Petitioner’s
argument about mitigating parasitic capacitance is untimely as to claim 15,
because the Petition does not mention parasitic capacitance with respect to
scan electrode lines. PO Sur-reply 12.
We have considered the parties’ argument and evidence as detailed
above, and we find Petitioner’s contentions persuasive. As with claim 1, we
find persuasive Petitioner’s rationale that a person of ordinary skill in the art
would have been motivated to modify Utsugi to leave the SiO2 layer in place
above the scan electrode lines, because Utsugi’s Figure 5 shows the SiO2
layer covering everything except for the location of the contact holes, and it
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would have added unnecessary complexity to remove the insulation above
the scan lines. Ex. 1007 ¶¶ 175–176. Further, Patent Owner has not
identified any benefit to undertaking an additional step to remove the SiO2
layer. Although the parties do not appear to dispute that a person of ordinary
skill in the art would not have been concerned with preventing a short with
respect to Utsugi’s scan electrode lines, we find that Petitioner’s rationale
for leaving the SiO2 layer in place (avoiding unnecessary additional
manufacturing steps) is sufficient to support a determination of obviousness
as to this claim limitation. Id. We do not rely on Petitioner’s argument
about mitigating parasitic capacitance and therefore need not address Patent
Owner’s contention that it is an improper Reply argument.
“a first driver circuit for selectively supplying said address
signal to said address lines in sequence; and
a second driver circuit for supplying said image data to said
data lines”
Petitioner contends Utsugi discloses that row selection in its active
matrix type luminous element array “is performed by sequentially selecting
corresponding one of row-addressed scan electrode lines,” which satisfies
claim 15’s limitation of selectively supplying an address signal to address
lines in sequence. Pet. 53 (citing Ex. 1003, 8:59–62; Ex. 1007 ¶¶ 161–162).
Petitioner further contends Utsugi discloses that signal electrode lines 1M
supply image data to current-controlling transistors QI. Id. (citing Ex. 1003,
Fig. 3; Ex. 1007 ¶¶ 164–165). Patent Owner does not dispute that Utsugi
discloses these functions.
Petitioner acknowledges that Utsugi does not discuss the circuitry
used to perform the functions recited in claim 15’s first and second driver
circuit limitations set forth above. Pet. 53. Petitioner contends, however,
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that a person of ordinary skill in the art would have understood that these
functions are performed by driver circuitry, and that implementing such
circuitry would have been well within the skill of a person of ordinary skill.
Id. at 53, 60–62 (citing Ex. 1007 ¶¶ 162, 165, 177–179; KSR, 550 U.S. at
417 (“application of a known technique to a piece of prior art ready for the
improvement”)). In addition to this supporting testimony from Dr.
Fontecchio, Petitioner relies on Mr. Flasck’s testimony as an admission that
“in the vast majority of cases for image displays, based on this type of
OLED technology – there would be drivers, driver circuits.” See Pet. Reply
24 (citing Ex. 1017, 170:22–171:3).
Patent Owner contends that Utsugi does not disclose any structure for
performing the functions of selectively supplying an address signal and
supplying image data to data lines. PO Resp. 21; PO Sur-reply 13. Patent
Owner further contends that there “are multiple different ways to select scan
electrode lines that do not involve a driver circuit” (PO Resp. 21 (citing Ex.
2001 ¶ 69)) and that Petitioner’s argument that any circuitry performing the
claimed functions is necessarily a driver circuit is unsupported by evidence
(PO Sur-reply 14).
We have considered the parties’ argument and evidence on this issue
as detailed above, and we find Petitioner’s contentions persuasive.
Petitioner’s rationale that driver circuits were known technology for
supplying image data is supported by the evidence, including Mr. Flasck’s
testimony. See Ex. 1007 ¶ 177; Ex. 1017, 170:22–171:3. We find less
persuasive Patent Owner’s contention that “it would not be unusual to
manually apply signals to particular lines in no particular order, such as in a
test device or an experimental device” (Ex. 2001 ¶ 69), because Patent
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Owner does not explain why a person of ordinary skill in the art would
choose that implementation over a driver circuit that its expert admits would
be used “in the vast majority of cases for image displays.” Ex. 1017,
170:22–171:3. Again, Patent Owner’s identification of a different obvious
modification does not undermine Petitioner’s showing that its proposed
modification would have been obvious.
We have also considered Patent Owner’s argument that Petitioner
improperly relies on prior art not included in the Petition, for disclosure of a
driver circuit. See Tr. 37. We determine, however, that Petitioner has
shown the knowledge of a person of ordinary skill in the art sufficiently
supplies a “driver circuit” to support that it would have been obvious to
modify Utsugi. See Koninklijke Philips N.V. v. Google LLC, 948 F.3d 1330
(Fed Cir. 2020) (“[I]t does not follow that we ignore the skilled artisan’s
knowledge when determining whether it would have been obvious to modify
the prior art.”) (citing Dow Jones & Co. v. Ablaise Ltd., 606 F.3d 1338,
1349, 1353 (Fed. Cir. 2010) (“[T]he obviousness ‘analysis requires an
assessment of the ‘. . . background knowledge possessed by a person having
ordinary skill in the art.’”)).
For the reasons discussed above, we conclude that Petitioner has
proven by a preponderance of the evidence that claim 15 would have been
obvious over Utsugi.
Other Challenged Claims
Petitioner provides additional contentions regarding Utsugi’s
disclosures relevant to the additional limitations of dependent claims 2 and
5–7. Pet. 31, 34–39, 56. Patent Owner does not separately address those
contentions; Patent Owner argues that Petitioner fails to show
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unpatentability for the same reasons Patent Owner raises for claim 1. PO
Resp. 9. We have reviewed the parties’ contentions and the full record and
conclude that Petitioner has proven by a preponderance of the evidence that
claims 2 and 5–7 would have been obvious over Utsugi, for the reasons
provided by Petitioner. See Pet. 31, 34–39, 56.
F. Alleged Obviousness Based on Utsugi and Manabe
Petitioner argues claim 3 would have been obvious over the combined
teachings of Utsugi and Manabe. Pet. 62–67. Claim 3 depends from claim 1
and additionally recites “wherein said at least one first electrode has a rough
surface which is in contact with said organic electroluminescent layer.”
Ex. 1001, 18:7–9.
According to Petitioner, Manabe discloses an EL structure comprising
a metal electrode, and teaches benefits of the metal electrode having a rough
surface in contact with the organic electroluminescent layer, including
“averaging of the interference effect and reducing angle dependence and
film thickness dependence” in order to improve display quality. Pet. 63–64
(citing Ex. 1004, Fig. 1, ¶¶ 24, 26; Ex. 1007 ¶¶ 181–183). Petitioner
contends a person of ordinary skill in the art would have recognized that
Utsugi’s structure incorporating a reflective first electrode would have a
problem with the viewing angle of the display, and would have been
motivated to optimize the viewing angle of Utsugi’s display by using
Manabe’s roughened electrode. Id. at 64–65 (citing Ex. 1004 ¶ 34; Ex. 1007
¶¶ 180–183, 185).
Patent Owner does not separately address Petitioner’s contentions as
to claim 3; Patent Owner argues that Petitioner fails to show unpatentability
for the same reasons Patent Owner raises for claim 1. PO Resp. 25. We
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have reviewed the parties’ contentions and the full record and conclude that
Petitioner has proven by a preponderance of the evidence that claim 3 would
have been obvious over the combination of Utsugi and Manabe, for the
reasons provided by Petitioner. See Pet. 62–67.
G. Alleged Obviousness Based on Utsugi and Eida
Petitioner argues claims 9, 11–13, 17, and 18 would have been
obvious over the combined teachings of Utsugi and Eida. Pet. 67–82.
Claims 9, 11–13, 17, and 18 depend directly or indirectly from claim 1 and
recite additional limitations of “wavelength conversion layers” for absorbing
light emitted from the organic electroluminescent layer and “filters” for
selectively permitting light rays in a wavelength range to pass. Ex. 1001,
18:53–58, 18:62–67, 19:1–13, 20:23–35. Petitioner addresses those
limitations with Eida.
According to Petitioner, Eida discloses both wavelength conversion
layers and color filters in an organic EL device, with the layers and filters
formed over an EL structure including a first electrode, an organic EL layer,
and a transparent second electrode, as in Utsugi. Pet. 67 (citing Ex. 1005,
Fig. 5, 1:5–8, 10:11–16; Ex. 1007 ¶ 191). Petitioner contends a person of
ordinary skill in the art would have been motivated to use Eida’s wavelength
conversion layers and color filters with Utsugi’s display structure, because
Utsugi explains that organic thin-film EL structures had possibility as a full-
colored wide display but does not provide details on the color aspect. Id. at
68 (citing Ex. 1003, 1:17–23). Petitioner contends that Eida’s express
teaching of using wavelength conversion layers and color filters in order to
optimize a multi-color light emission apparatus for use in multicolor or full-
color displays constitutes application of a known technique to a piece of
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prior art ready for the improvement. Id. at 70 (citing Ex. 1007 ¶ 192; KSR,
550 U.S. at 417 (“application of a known technique to a piece of prior art
ready for the improvement”)).
Patent Owner does not separately address Petitioner’s contentions as
to claims 9, 11–13, 17, and 18; Patent Owner argues that Petitioner fails to
show unpatentability for the same reasons Patent Owner raises for claim 1.
PO Resp. 25. We have reviewed the parties’ contentions and the full record
and conclude that Petitioner has proven by a preponderance of the evidence
that claims 9, 11–13, 17, and 18 would have been obvious over the
combination of Utsugi and Eida, for the reasons provided by Petitioner. See
Pet. 67–82.
H. Alleged Anticipation Based on Utsugi
For the reasons discussed above, Petitioner has shown, by a
preponderance of the evidence, that claims 1–9, 11–13, and 15–18 of the
’450 patent are unpatentable as obvious over Utsugi alone, Utsugi and
Manbe, or Utsugi and Eida. In addressing these grounds, we have addressed
all of the challenged claims. See 35 U.S.C. § 318(a) (requiring the Board to
“issue a final written decision with respect to the patentability of any patent
claim challenged by the petitioner and any new claim added under section
316(d)”); see also SAS Inst. Inc. v. Iancu, 138 S. Ct. 1348, 1359 (2018)
(holding that a petitioner “is entitled to a final written decision addressing all
of the claims it has challenged”). Accordingly, we need not and do not
decide whether Petitioner has shown by a preponderance of the evidence that
claims 1, 2, 4–8, 15, and 16 are anticipated by Utsugi. Cf. In re Gleave, 560
F.3d 1331, 1338 (Fed. Cir. 2009) (not reaching other grounds of
unpatentability after affirming the anticipation ground); see also Beloit
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Corp. v. Valmet Oy, 742 F.2d 1421, 1423 (Fed. Cir. 1984) (holding that once
a dispositive issue is decided, there is no need to decide other issues).
IV. CONCLUSION
Petitioner has shown, by a preponderance of the evidence, that claims
1, 2, 4–8, 15, and 16 are unpatentable under § 103(a) over Utsugi; claim 3 is
unpatentable under § 103(a) over the combination of Utsugi and Manabe;
and claims 9, 11–13, 17, and 18 are unpatentable under § 103(a) over the
combination of Utsugi and Eida,6 as summarized below:
Claims 35 U.S.C. § Reference(s)/Basis
Claims
Shown
Unpatentable
Claims Not
Shown
Unpatentable
1, 2, 4–8,
15, 16
102(e)7 Utsugi
1, 2, 4–8,
15, 16
103(a) Utsugi 1, 2, 4–8, 15,
16

3 103(a) Utsugi,
Manabe
3
9, 11–13,
17, 18
103(a) Utsugi, Eida 9, 11–13, 17,
18

Overall
Outcome
1–9, 11–13,
15–18

6 Should Patent Owner wish to pursue amendment of the challenged claims
in a reissue or reexamination proceeding subsequent to the issuance of this
Decision, we draw Patent Owner’s attention to the April 2019 Notice
Regarding Options for Amendments by Patent Owner Through Reissue or
Reexamination During a Pending AIA Trial Proceeding. See 84 Fed. Reg.
16654 (Apr. 22, 2019). If Patent Owner chooses to file a reissue application
or a request for reexamination of the challenged patent, we remind Patent
Owner of its continuing obligation to notify the Board of any such related
matters in updated mandatory notices. See 37 C.F.R. § 42.8(a)(3), (b)(2).
7 As explained in the previous section, we need not and do not decide
whether Petitioner has shown by a preponderance of the evidence that
Utsugi anticipates the challenged claims.
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V. ORDER
In consideration of the foregoing, it is hereby:
ORDERED that claims 1–9, 11–13, and 15–18 of the ’450 patent are
held to be unpatentable; and
FURTHER ORDERED that because this is a Final Written Decision,
parties to this proceeding seeking judicial review of our decision must
comply with the notice and service requirements of 37 C.F.R. § 90.2.

IPR2020-00140
Patent 6,072,450

40

PETITIONER:

David A. Garr
Grant Johnson
Peter P. Chen
COVINGTON & BURLING LLP
David Garr dgarr@cov.com
Grant Johnson gjohnson@cov.com
Peter Chen pchen@cov.com

PATENT OWNER:

Neil A. Rubin
Reza Mirzaie
Kent N. Shum
RUSS AUGUST & RABAT
nrubin@raklaw.com
rmirzaie@raklaw.com
kshum@raklaw.com