PTAB

IPR2021-01573

TCT Mobile US Inc v. Semiconductor Energy Laboratory Co Ltd

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Key Events
Petition

1. Case Identification

2. Patent Overview

  • Title: Light Emitting Devices and Image Playback Devices
  • Brief Description: The ’199 patent discloses an Organic Light Emitting Diode (OLED) display device that utilizes two types of electroluminescent (EL) elements within its pixels. One element uses a triplet compound for high luminance at low voltage, and the other uses a singlet compound for lower luminance at high voltage, aiming to improve luminance control and reduce power consumption.

3. Grounds for Unpatentability

Ground 1: Anticipation over ’475 patent - Claims 1 and 4 are anticipated by the ’475 patent under 35 U.S.C. §102.

  • Prior Art Relied Upon: ’475 patent (Patent 6,458,475).
  • Core Argument for this Ground:
    • Prior Art Mapping: Petitioner argued that the ’475 patent, which was not considered during prosecution, teaches every element of claims 1 and 4. The ’475 patent discloses a vertically stacked OLED where each pixel functions as an EL element, thus teaching the claimed "first EL element" and "second EL element" over a substrate. Petitioner asserted that the ’475 patent’s disclosure of an emitter layer doped with both a green phosphorescent (triplet) dye and a red fluorescent (singlet) dye satisfies the limitations requiring a first EL layer with a triplet compound and a second EL layer with a singlet compound. Furthermore, the ’475 patent explicitly describes a basic heterostructure with at least one hole transporting layer, meeting the final limitation of claim 1. For dependent claim 4, the ’475 patent’s example of using "fac tris(2-phenylpyridine)iridium" was argued to directly teach a triplet compound that includes iridium.

Ground 2: Obviousness over ’475, ’555, and ’315 - Claims 5 and 8 are obvious over the ’475 patent in view of the ’555 and ’315 patents under 35 U.S.C. §103.

  • Prior Art Relied Upon: ’475 patent (Patent 6,458,475), ’555 patent (Patent 5,684,555), and ’315 patent (Patent 6,522,315).
  • Core Argument for this Ground:
    • Prior Art Mapping: Petitioner contended that the ’475 patent provides the core OLED structure with both singlet and triplet compounds. The ’315 patent was asserted to supply the missing circuit-related elements, teaching a pixel portion including a first thin-film transistor (TFT) over a first substrate and a driver circuit with a second TFT. The ’555 patent was argued to teach the remaining structural layout limitations of claim 5, including a second substrate for the driver circuit and a flexible printed circuit (FPC) to connect the first and second substrates.
    • Motivation to Combine: A POSITA seeking to build a practical, large-area display would combine these references. The POSITA would start with the efficient OLED materials of the ’475 patent and incorporate the known pixel and driver circuit designs from the ’315 patent. To enhance the display viewing area and improve manufacturing yields—common goals in the field—the POSITA would be motivated by the ’555 patent to physically separate the driver circuitry onto a second substrate and connect it with an FPC, which was a known technique for reducing display bezel size.
    • Expectation of Success: A POSITA would have an expectation of success in this combination, as integrating established circuit layouts with known display materials using standard connection technologies was a conventional and predictable design approach at the time.

Ground 3: Obviousness over ’475 and ’359 - Claims 13 and 16 are obvious over the ’475 patent in view of the ’359 application under §103.

  • Prior Art Relied Upon: ’475 patent (Patent 6,458,475) and the ’359 application (European Application # EP0917359).
  • Core Argument for this Ground:
    • Prior Art Mapping: Petitioner argued that the combination renders claim 13 obvious by incorporating the advanced OLED display of the ’475 patent into the consumer electronic device taught by the ’359 application. While the ’475 patent provides the underlying display structure with triplet and singlet emitters, the ’359 application was asserted to teach the claimed "image playback device," disclosing an electronic camera with a main body, an operation switch, and a display portion over a substrate.
    • Motivation to Combine: A POSITA would be motivated to replace the older liquid crystal display (LCD) in the ’359 application's camera with the superior OLED technology from the ’475 patent. This modification would be a predictable product improvement to achieve a brighter display, better power efficiency, and enhanced battery life. The ’475 patent’s suggestion that its OLEDs are suitable for various displays would naturally lead a POSITA to consider its use in a portable device like a camera.
    • Expectation of Success: A POSITA would have expected success, as swapping one display module type for another in a consumer device was a routine engineering task aimed at improving performance.
  • Additional Grounds: Petitioner asserted additional obviousness challenges for claims 9 and 12 over the ’475 patent in view of the ’315 patent, relying on similar motivations to integrate known pixel and driver circuit designs with the core OLED technology.

4. Key Claim Construction Positions

  • "EL layer": Petitioner proposed construing this term as "all the layers that are placed between an anode and cathode," based on an explicit definition in the ’199 patent’s specification. This construction is broad and encompasses various functional layers, not just the light-emitting layer itself.
  • "EL element": Petitioner proposed construing this as "an element of a pixel which includes an anode, EL layer, and a cathode." This construction distinguishes the overall pixel structure (the "element") from the stack of organic films (the "layer").

5. Arguments Regarding Discretionary Denial

  • Petitioner argued that discretionary denial under §325(d) was improper because none of the asserted prior art references were cited or considered by the Examiner during the original prosecution.
  • Petitioner argued that discretionary denial under the Fintiv factors was inappropriate. The parallel district court litigation was asserted to be in its infancy, with no trial date set, limited discovery completed, and no claim construction briefing scheduled. These factors were argued to weigh overwhelmingly in favor of institution.

6. Relief Requested

  • Petitioner requests institution of an inter partes review and cancellation of claims 1, 4, 5, 8, 9, 12, 13, and 16 of Patent 7,372,199 as unpatentable.