Universal Display Corporation

Patent Trials and Appeals Board

Aug 27, 2021

2021000465 (P.T.A.B. Aug. 27, 2021)

UNITED STATES PATENT AND TRADEMARK OFFICE
UNITED STATES DEPARTMENT OF COMMERCE
United States Patent and Trademark Office
Address: COMMISSIONER FOR PATENTS
P.O. Box 1450
Alexandria, Virginia 22313-1450
www.uspto.gov
APPLICATION NO. FILING DATE FIRST NAMED INVENTOR ATTORNEY DOCKET NO. CONFIRMATION NO.
15/825,493 11/29/2017 Ruiqing MA UDC-1188US 6303
108576 7590 08/27/2021
Butzel Long / UDC
Butzel Long
1909 K St. NW
Suite 500
Washington, DC 20006
EXAMINER
ENAD, CHRISTINE A
ART UNIT PAPER NUMBER
2811
NOTIFICATION DATE DELIVERY MODE
08/27/2021 ELECTRONIC
Please find below and/or attached an Office communication concerning this application or proceeding.
The time period for reply, if any, is set in the attached communication.
Notice of the Office communication was sent electronically on above-indicated "Notification Date" to the
following e-mail address(es):
docket@butzel.com
kamlay@butzel.com
PTOL-90A (Rev. 04/07)
UNITED STATES PATENT AND TRADEMARK OFFICE
____________________

BEFORE THE PATENT TRIAL AND APPEAL BOARD
____________________

Ex parte RUIQING MA,
MICHAEL HACK, and
JULIA J. BROWN
____________________

Appeal 2021-000465
Application 15/825,4931
Technology Center 2800
____________________

Before JAMES C. HOUSEL, MICHELLE N. ANKENBRAND, and
JULIA HEANEY, Administrative Patent Judges.

HOUSEL, Administrative Patent Judge.

DECISION ON APPEAL

A. STATEMENT OF THE CASE
Appellant filed an appeal under 35 U.S.C. § 134(a) from the
Examiner’s final decision rejecting claims 1–15.
We have jurisdiction under 35 U.S.C. § 6(b).2
We REVERSE.

1 We use the word “Appellant” to refer to “applicant” as defined in
37 C.F.R. § 1.42. Appellant identifies Universal Display Corporation as the
real party in interest. Appeal Brief (“Appeal Br.”) filed May 6, 2020, 1.
2 Our Decision additionally refers to the Specification (“Spec.”) filed
November 29, 2017, the Final Office Action (“Final Act.”) dated September
13, 2019, the Examiner’s Answer (“Ans.”) dated August 21, 2020, and the
Reply Brief (“Reply Br.”) dated October 21, 2020.
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CLAIMED SUBJECT MATTER
The subject matter on appeal relates to devices that include organic
light emitting diodes/devices (OLEDs), a thin film barrier, and optical layers
(see, e.g., claim 1). Specifically, the Specification describes a device that
includes a substrate, an OLED disposed over the substrate, a high index
optical layer disposed over the OLED, a thin film barrier disposed over the
high index optical layer, and a low index optical layer disposed over the thin
film barrier. Spec ¶ 14. The Specification describes various analyses to
determine what high index optical layers, thin film barriers, and low index
optical layers provide an acceptable color and luminance level. Id. ¶¶ 62–
84.
Independent claim 1 is illustrative and is reproduced below from the
Claims Appendix of the Appeal Brief.
1. A device comprising:
a substrate;
an OLED disposed over the substrate and comprising a
first emissive layer configured to emit light of a first color;
a high index optical layer having a refractive index of not
less than 1.7 disposed over the OLED;
a thin film barrier disposed over the high index optical
layer; and
a low index optical layer having a refractive index of not
more than 1.6 disposed over the thin film barrier.

Appeal Br. 11 (Claims App.).

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REJECTIONS ON APPEAL
The Examiner maintains, and Appellant requests our review of, the
following grounds of rejection under 35 U.S.C. § 103:
I. Claim 1 as unpatentable over Kumar3 and Chu;4
II. Claims 2 and 3 as unpatentable over Kumar, Chu, and
Ikeda;5
III. Claims 4–10 as unpatentable over Kumar, Chu, and
Yonemoto;6
IV. Claims 11 and 13 as unpatentable over Kumar, Chu, and
Nagaya;7
V. Claim 12 as unpatentable over Kumar, Chu, and Yoo;8
and
VI. Claims 14 and 15 as unpatentable over Kumar, Chu, and
Kwak.9 Final Act. 3–7.
B. DISCUSSION
Rejection I
Claim 1 is rejected under 35 U.S.C. § 103 as unpatentable over Kumar
and Chu.
The Examiner finds Kumar discloses a device that includes a
substrate, an OLED disposed over the substrate, a first optical layer disposed

3 Kumar et al., US 2010/0294024 A1, published Nov. 25, 2010 (“Kumar”).
4 Chu et al., US 2017/0315389 A1, published Nov. 2, 2017 (“Chu”).
5 Ikeda et al., US 2007/0211335 A1, published Sept. 13, 2007 (“Ikeda”).
6 Yonemoto et al., US 2017/0199315 A1, published July 13, 2017
(“Yonemoto”).
7 Nagaya et al., US 2018/0017721 A1, published Jan. 18, 2018 (“Nagaya”).
8 Yoo et al., US 2017/0062680 A1, published Mar. 2, 2017 (“Yoo”).
9 Kwak et al., US 2017/0247579 A1, published Aug. 31, 2017 (“Kwak”).
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over the OLED, a thin film barrier disposed over the first optical layer, and a
second optical layer disposed over the thin film barrier. Final Act. 3. The
Examiner acknowledges that Kumar does not disclose the refractive index of
the layers. Id.
The Examiner finds Chu discloses a device that includes a substrate,
an OLED disposed over the substrate, a high index optical layer having a
refractive index of not less than 1.7, a thin film barrier disposed over the
high index optical layer, and a low index optical layer having a refractive
index of not more than 1.6 disposed over the thin film barrier. Id. The
Examiner concludes it would have been obvious to modify Kumar’s optical
layers in view of Chu so they have different refractive indices and provide
improved light transmission. Id. The Examiner also concludes it would
have been obvious to modify Kumar in view of Chu to discover the optimal
or workable ranges for the refractive indices of Kumar’s optical layers and
arrive at the claimed invention. Id. at 3–4.
Appellant asserts that the invention, which uses optical layers above
and below a thin film barrier, “can achieve more consistent color, as well as
improved luminance and efficiency, in comparison to a conventional device
that uses only the thin film barrier.” Appeal Br. 2. According to Appellant,
the “combination of layers with specific relative indices of refraction allows
devices according to the present claims to achieve the benefits described.”
Id.
With regard to the rejection, Appellant contends that claim 1 requires
layers arranged in a particular order, “with the high-index layer (HOL) being
closer to the OLED, followed by the thin film barrier and LOL [low index
optical layer], in order,” because the Specification defines “disposed over”
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as “[w]here a first layer is described as ‘disposed over’ a second layer, the
first layer is disposed further away from the substrate.” Id. at 3 (citing Spec.
¶ 7).
Appellant argues that Kumar discloses only two optical layers
123,125 but does not describe their properties. Id. Appellant asserts that the
Examiner cites Chu’s layers 370a, 350b, and 370b as the claimed high-index
optical layer, thin film barrier, and the low index optical layer. Id. at 4.
Appellant, however, contends that Chu describes capping layers 350a, 350b
and optical layers 370a, 370b as being configured to reflect light after it has
been emitted by Chu’s light assembly 500 and converted by color
conversion layers 330 so the light is directed back in the direction of a user.
Id. Appellant also argues that Chu’s structure is opposite to the claimed
structure because Chu’s optical layer 370b (which the Examiner identifies as
the claimed low index optical layer) is closer to Chu’s light assembly 500
than Chu’s capping layer 350b (which the Examiner identifies as the claimed
thin film barrier) and Chu’s optical layer 370a (which the Examiner
identifies as the claimed high index optical layer). Id. at 4–5.
Appellant further asserts that it would not have been obvious to
reverse the order of Chu’s arrangement because Chu describes internal
reflection effects caused by its capping and optical layers to direct light
towards a user and increase the amount of light emitted from Chu’s device.
Id. at 6–7. Appellant argues that reversing the order of layers Chu teaches
would defeat the purpose of Chu’s arrangement. Id. at 7. With regard to the
Examiner’s reasons to combine Kumar and Chu, Appellant argues the
Examiner’s reasoning that reversing Chu’s structure would improve light
transmission is unsupported, and the Examiner has not shown that the
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claimed arrangement would have been optimum or workable in view of
Chu’s disclosure. Id.
Appellant’s arguments are persuasive. The Examiner finds that Chu’s
first optical layer 370a functions as a high index optical layer, Chu’s second
capping layer 350b functions as a thin film barrier, and Chu’s second optical
layer 370b functions as a low index optical layer. Final Act. 3; Ans. 4.
However, we agree with Appellant that Chu teaches an arrangement in
which first capping layer 350a has a high refractive index and adjacent first
optical layer 370a has a low refractive index, so light passing through first
capping layer 350a and having a large incident angle is reflected back
through first capping layer 350a toward a user. Chu ¶¶ 75, 78–79, Fig. 1A.
Similarly, light passing through Chu’s second capping layer 350b is
reflected back through second capping layer 350b because second capping
layer 350b has a high refractive index and the adjacent second optical layer
has a low refractive index. Id. ¶¶ 77–79.
The Examiner does not sufficiently explain why the claimed device
would have been obvious in view of Kumar and Chu. Kumar’s Figure 3 is
reproduced below.

Kumar’s Figure 3 shows an encapsulated device
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The Examiner finds that Kumar’s optical layers 123 and 125 function
as claim 1’s optical layers and Kumar’s nanoparticulate layer 121 functions
as claim 1’s thin film barrier. Ans. 3. Thus, Kumar’s structure has a layer
(nanoparticulate layer 121) between optical layers 123,125 and does not
provide an arrangement in which there could be adjacent optical layers of
high and low refractive index that cause total internal reflection at their
interface. The Examiner’s reasons to combine (i.e., the improvement of
light transmission and the optimization of the refractive indices of Kumar’s
optical layers) are insufficient to explain why it would have been obvious to
modify Kumar’s device in view of Chu’s teachings, which relate to adjacent
layers of high and low index material that cause internal reflection, and
arrive at the claimed structure.
Furthermore, when we consider Chu’s layers that the Examiner
identifies as the claimed high index optical layer, thin film barrier, and low
index optical layer (i.e., first optical layer 370a, second capping layer 350b,
and second optical layer 370b), they are arranged in a reverse order from
what is claimed relative to a light emitting structure (i.e., claim 1’s OLED).
Chu’s Figure 1A is reproduced below.

Chu’s Figure 1A is a cross-sectional view of a display device
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Chu discloses light assembly 500 that provides light to color
conversion panel 30. Chu ¶ 39. Therefore, Chu’s light assembly 500 is a
light emitting structure. However, the layer the Examiner identifies as a low
index optical layer (i.e., Chu’s second optical layer 370b) is disposed over
light assembly 500, the layer the Examiner identifies as a thin barrier film
(i.e., second capping layer 350b) is disposed over the second optical layer,
and the layer the Examiner identifies as a high index optical layer (i.e.,
Chu’s first optical layer 370a) is disposed above those layers. This is in
reverse order to claim 1’s structure in which the high index optical layer is
disposed over the OLED, the thin film barrier is disposed over the high
index optical layer, and the low index optical layer is disposed over the thin
film barrier.
The Examiner finds “[t]here is no teaching in Chu’s disclosure that
discourage or criticizes reversing the order of the layers.” Ans. 4. To the
extent the Examiner concludes it would have been obvious to modify Kumar
in view of Chu and arrive at the claimed arrangement by reversing the order
of Chu’s layers, we agree with Appellant that such a modification would not
have been obvious to one of ordinary skill in the art. Appeal Br. 6–7. Chu
describes a particular structure of high index layers (i.e., capping layers
350a, 350b) above adjacent low index layers (i.e., optical layers 370a, 370b)
relative to light assembly 500 so light is internally reflected in a direction
toward the top of Chu’s Figure 1A and toward a user. To the extent one
would have considering modifying Kumar in view of Chu, the Examiner
does not sufficiently explain why it would have been obvious to reverse the
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order of Chu’s layers, which would defeat this purpose and cause light to be
reflected back towards the light emitting layer and away from a user.
[C]ombinations that change the “basic principles under which
the [prior art] was designed to operate,” In re Ratti, 46 CCPA
976, 270 F.2d 810, 813 (1959), or that render the prior art
“inoperable for its intended purpose,” In re Gordon, 733 F.2d
900, 902 (Fed. Cir. 1984), may fail to support a conclusion of
obviousness.
Plas-Pak Indus., Inc. v. Sulzer Mixpac AG, 600 F.App’x 755, 758 (Fed. Cir.
2015).
The Examiner further finds Chu discloses that second capping layer
350b can include a stack of layers having different refractive indices.
Ans. 4. Chu discloses that second capping layer 350b may include a
structure in which films of high refractive index and films of low refractive
index are alternately stacked so this structure causes constructive or
destructive interference for light of a specific wavelength. Chu ¶ 68.
However, as discussed above, Kumar’s structure includes optical layers 123,
125 separated by nanoparticulate layer 121. Thus, Kumar’s optical layers
123, 125 are not in an alternately stacking arrangement, like the alternating
high and low refractive index layers of Chu’s second capping layer 350b.
Therefore, the Examiner merely directs us to Chu’s disclosure regarding
second capping layer 350b without sufficiently explaining why it would
have been obvious to modify Kumar’s structure in view of Chu’s teachings
to arrive at claim 1’s device.
In addition, the Examiner finds that Chu describes light emission rates
for different combinations of optical layers and capping layers and Chu
determines that the emission rate is highest when a device includes a first
and second optical layer. Ans. 4–5. The passage the Examiner refers to
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merely describes a first embodiment having Chu’s first optical layer between
first and second capping layers, a second embodiment having Chu’s second
optical layer between the first and second capping layers, and a third
embodiment having both of Chu’s optical layers. Chu ¶ 112. Chu
determines that the embodiments have higher light emissions rates than a
comparative embodiment, which does not include an optical layer, and that
the third embodiment has the highest light emission rate. Id. ¶¶ 112–113.
The Examiner, however, does not sufficiently explain how this relates to the
claimed structure or how this supports a conclusion that the claimed
structure would have been obvious in view of Kumar and Chu.
For the reasons discussed above, Appellant’s arguments identify a
reversible error in the Examiner’s rejection of claim 1. Therefore, we do not
sustain the Examiner’s § 103 rejection of claim 1 as unpatentable over
Kumar and Chu.
Rejections II–VI
The Examiner does not rely on the additional references in the
rejections of claims 2–15 to remedy the deficiencies discussed above with
regard to the rejection of claim 1.10 Therefore, we do not sustain the
Examiner’s § 103 rejections of claims 2–15.
CONCLUSION
Upon consideration of the record and for the reasons set forth above
and in the Final Office Action and the Examiner’s Answer, the Examiner’s
decision to reject claims 1–15 under 35 U.S.C. § 103 is reversed.

10 Appellant presents arguments for the rejection of claims 4–10 under § 103
over Kumar, Chu, and Yonemoto. Appeal Br. 8–10. As noted in
Appellant’s Reply Brief, the Examiner did not respond to these arguments.
Reply Br. 5; see generally Ans.
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SUMMARY
In summary:

Claim(s)
Rejected 35 U.S.C. § References/Basis Affirmed Reversed
1 103 Kumar, Chu 1
2, 3 103 Kumar, Chu, Ikeda 2, 3
4–10 103 Kumar, Chu, Yonemoto 4–10
11, 13 103 Kumar, Chu, Nagaya 11, 13
12 103 Kumar, Chu, Yoo 12
14, 15 103 Kumar, Chu, Kwak 14, 15
Overall
Outcome 1–15

REVERSED