DCT

2:20-cv-00285

Japan Display Inc v. Tianma Microelectronics Co Ltd

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I. Executive Summary and Procedural Information

  • Parties & Counsel:
  • Case Identification: 2:20-cv-00285, E.D. Tex., 08/31/2020
  • Venue Allegations: Plaintiff alleges venue is proper because Defendant is a non-U.S. resident and conducts substantial business in the district through intermediaries, distributors, and a U.S. subsidiary, Tianma America Inc., which has a representative in Texas and distributes the accused products to customers in the state.
  • Core Dispute: Plaintiff alleges that Defendant’s thin-film transistor (TFT) liquid crystal display (LCD) panels infringe three patents related to the structural design and component arrangement of display devices.
  • Technical Context: The technology concerns specific structural configurations of electrodes, wiring, and connection pads within TFT LCDs, which are foundational components for high-resolution, power-efficient displays used in smartphones, tablets, and automotive systems.
  • Key Procedural History: The complaint does not mention any prior litigation, Inter Partes Review (IPR) proceedings, or licensing history related to the patents-in-suit.

Case Timeline

Date Event
2005-10-31 Priority Date for U.S. Patent No. 7,385,665
2007-02-26 Priority Date for U.S. Patent No. 7,636,142
2008-06-10 U.S. Patent No. 7,385,665 Issued
2009-12-22 U.S. Patent No. 7,636,142 Issued
2013-12-09 Priority Date for U.S. Patent No. 9,939,698
2018-04-10 U.S. Patent No. 9,939,698 Issued
2020-08-31 Complaint Filed

II. Technology and Patent(s)-in-Suit Analysis

U.S. Patent No. 7,636,142 - "Liquid Crystal Display Device"

Issued: December 22, 2009 (’142 Patent)

The Invention Explained

  • Problem Addressed: The patent seeks to solve the problem of 'disclination,' a visual defect that can lower display quality in certain types of advanced LCDs, such as those using Fringe Field Switching (FFS) technology. This defect can arise from the shape of the electric fields around the edges of openings in the display's electrodes. ('142 Patent, col. 1:46-61, col. 2:35-43).
  • The Patented Solution: The invention proposes a specific structural arrangement of the display's electrodes to control the electric field shape. It calls for an 'electric field opening part' in the upper electrode to be intentionally 'overlapped' with a 'window-shaped opening part' in the lower electrode. This overlap is designed to prevent the formation of the undesirable, arc-shaped electric fields that cause disclination, thereby improving display quality. (Compl. ¶22; ’142 Patent, Abstract, col. 3:5-20).
  • Technical Importance: This design aimed to improve the visual performance and manufacturing yield of high-resolution LCDs by mitigating a known artifact, which was a relevant concern for producing displays with superior viewing angles and image quality. (Compl. ¶22).

Key Claims at a Glance

  • The complaint asserts independent claim 1. (Compl. ¶37).
  • The essential elements of independent claim 1 include:
    • A liquid crystal display device comprising an upper electrode and a lower electrode interposing an insulation layer.
    • An electric field opening part formed in the upper electrode.
    • An upper electrode wiring and the upper electrode disposed below the lower electrode.
    • A window-shaped opening part formed by partially removing the lower electrode for connecting the upper electrode wiring and the upper electrode.
    • One end portion of the electric field opening part is disposed to be overlapped with the window-shaped opening part in a plan view.
  • The complaint does not explicitly reserve the right to assert dependent claims.

U.S. Patent No. 7,385,665 - "Display Device"

Issued: June 10, 2008 (’665 Patent)

The Invention Explained

  • Problem Addressed: The patent addresses challenges in designing displays with narrow bezels (the 'picture-frame-shaped region'). As display resolution increases, more connection wiring is needed, which can widen the bezel. Additionally, shrinking the connection pitch to save space can cause 'defective connection' when bonding the flexible board to the display panel due to non-uniform thermal distribution. ('665 Patent, col. 1:32-59).
  • The Patented Solution: The invention introduces 'dummy pads' and 'dummy terminals' into the connection area between the display panel and its driving source. A 'dummy pad group' is placed between the functional 'connection pad groups.' These dummy structures, which are not connected to the display's active wiring, are intended to make the thermal distribution more uniform during the thermal press-bonding process, thereby preventing connection defects while allowing for a more compact and reliable layout. (Compl. ¶24; ’665 Patent, Abstract, col. 5:8-16).
  • Technical Importance: This invention provided a method to address both manufacturing yield and aesthetic design constraints, facilitating the production of reliable, high-resolution displays with the thin bezels demanded by the consumer electronics market. (Compl. ¶24).

Key Claims at a Glance

  • The complaint asserts independent claim 1. (Compl. ¶51).
  • The essential elements of independent claim 1 include:
    • A display device with a display panel, a driving signal source, and a connection part.
    • The connection part comprising a 'first connection section' (on the panel) and a 'second connection section' (on the driving source).
    • The first connection section includes at least two 'connection pad groups' and a 'dummy pad group' disposed between them.
    • The second connection section includes 'connection terminal groups' corresponding to the connection pads and a 'dummy terminal group' corresponding to the dummy pads.
  • The complaint does not explicitly reserve the right to assert dependent claims.

U.S. Patent No. 9,939,698 - "Liquid Crystal Display Device"

Issued: April 10, 2018 (’698 Patent)

  • Technology Synopsis: This patent addresses the challenge of achieving high-definition screens without increasing display thickness by optimizing the structure around the through-hole that connects different layers. The invention describes a pixel electrode that covers the side wall of the through-hole and has a slit, where the end of the slit overlaps with the side wall, a configuration designed to improve the flow of alignment film material and prevent display defects caused by thickness unevenness. (Compl. ¶26; ’698 Patent, Abstract).
  • Asserted Claims: Independent claim 1. (Compl. ¶67, ¶68).
  • Accused Features: The complaint alleges that the accused TFT LCD panels, such as the TL062FVMC70 and TL079QDXP02, contain the claimed transistor substrate structure, including the specific configuration of the pixel electrode, through-hole, and slit. (Compl. ¶67, ¶69). The complaint provides scanning electron microscope images purporting to show this structure. (Compl. p. 31, 33).

III. The Accused Instrumentality

Product Identification

  • The accused instrumentalities are TFT LCD panels designed, manufactured, and sold by Tianma, including at least models TL062FVMC70, TM062JDSC03, TL079QDXP02, and TM070RDHP03. (Compl. ¶28). These panels are alleged to be incorporated into end-user products such as the Motorola Moto G7 and G7 Power smartphones, the Asus ZenPad S 8.0 tablet, and the Mazda 3 automobile. (Compl. ¶10, ¶28-31).

Functionality and Market Context

  • The accused panels are low-temperature polycrystalline silicon (LTPS) TFT LCDs, a technology that enables higher resolution and lower power consumption in displays for consumer and industrial electronics. (Compl. ¶2). The complaint alleges that Tianma is a major global manufacturer and supplier of these panels, with its products being widely distributed and sold in the U.S. and Texas through various channels, including a wholly-owned U.S. subsidiary, Tianma America. (Compl. ¶7, ¶11, ¶27). The complaint provides a teardown photograph of a Motorola Moto G7 smartphone, identifying the accused Tianma LCD panel model number TL062FVMC70 inside the device. (Compl. p. 6). A similar teardown photograph identifies the accused panel model TL079QDXP02 inside an Asus ZenPad S 8.0 tablet. (Compl. p. 8).

IV. Analysis of Infringement Allegations

’142 Patent Infringement Allegations

Claim Element (from Independent Claim 1) Alleged Infringing Functionality Complaint Citation Patent Citation
A liquid crystal display device comprising: an upper electrode and a lower electrode interposing an insulation layer therebetween... The accused TL062FVMC70 panel is alleged to be a liquid crystal display device containing an upper electrode, a lower electrode, and an insulation layer between them. A scanning electron microscope (SEM) image is provided to show these layers. (Compl. p. 16). ¶40 col. 10:49-53
...wherein an electric field opening part for passing an electric field is formed in the upper electrode and liquid crystal molecules are driven by applying a voltage between the lower electrode and the upper electrode, The accused panel allegedly has an 'electric field opening part' in its upper electrode for driving the liquid crystal molecules. The complaint provides an SEM image purporting to show this feature. (Compl. p. 17). ¶41 col. 11:43-50
...wherein an upper electrode wiring and the upper electrode which interpose an interlayer insulation film therebetween, together is disposed below the lower electrode, The accused panel allegedly has an upper electrode wiring and upper electrode located below the lower electrode, separated by an interlayer insulation film. This structure is identified in an SEM cross-section image. (Compl. p. 18). ¶42 col. 10:54-58
...wherein a window-shaped opening part formed by partially removing the lower electrode for connecting the upper electrode wiring and the upper electrode, and wherein one end portion of the electric field opening part...is disposed to be overlapped with the window-shaped opening part in a plan view. The complaint alleges the accused panel has a 'window-shaped opening part' in the lower electrode that overlaps with the 'electric field opening part' in the upper electrode. This overlap is illustrated with annotated plan-view and cross-section SEM images. (Compl. p. 19). ¶43 col. 10:59-67
  • Identified Points of Contention:
    • Scope Questions: A central question will be whether the structures identified in the accused panels meet the claim definitions of 'electric field opening part' and 'window-shaped opening part.' The defense may argue that the claim terms, when read in light of the specification, require specific functional characteristics beyond the simple structural arrangement shown in the complaint's images.
    • Technical Questions: The complaint provides SEM images showing a structural overlap. However, the patent's purpose for this overlap is functional: to suppress disclination. ( '’142 Patent, col. 3:21-33). A key evidentiary question will be whether the overlap in the accused device actually performs this function or if it is an incidental feature of a different design.

’665 Patent Infringement Allegations

Claim Element (from Independent Claim 1) Alleged Infringing Functionality Complaint Citation Patent Citation
A display device comprising: a display panel which includes an effective display section... a driving signal source... a connection part at which the display panel and the driving signal source are connected; and a plurality of connection wiring lines... The accused TM062JDSC03 and TM070RDHP03 panels are alleged to be display devices with these components. An annotated optical microscope image identifies the 'Display Panel,' 'Effective Display Section,' 'Driving Signal Source,' and 'Connection Part.' (Compl. p. 23, 25). ¶54, ¶57 col. 2:2-9
...the connection part comprising: a first connection section including at least two connection pad groups... and a dummy pad group which is disposed between the at least two connection pad groups and is composed of dummy pads; The connection part of the accused panels is alleged to include a first connection section with at least two 'Connection Pad Groups' and a 'Dummy Pad Group' situated between them. The complaint provides a labeled optical microscope image of the TM062JDSC03 and TM070RDHP03 panels to illustrate this structure. (Compl. p. 24, 26). ¶55, ¶58 col. 2:9-15
...and a second connection section including connection terminal groups which are composed of connection terminals corresponding to the connection pads, and a dummy terminal group which is composed of dummy terminals corresponding to the dummy pads. The accused panels' connection part allegedly includes a second connection section with 'Connection Terminal Groups' and a 'Dummy Terminal Group' that correspond to the pad groups on the first connection section. This is also identified in the annotated microscope images. (Compl. p. 24, 26). ¶55, ¶58 col. 2:15-19
  • Identified Points of Contention:
    • Scope Questions: What constitutes a 'dummy pad' or 'dummy terminal'? The patent suggests they are structurally present but not connected to active wiring. (’665 Patent, col. 5:11-14). The defense may argue that the structures JDI labels as 'dummy' serve an unaccused electrical or structural function, and thus do not meet the claim definition.
    • Technical Questions: The patent's stated purpose for the dummy pads is to improve thermal uniformity during manufacturing. (’665 Patent, col. 5:8-16). The infringement analysis may turn on whether the accused structures are present for this reason, or if their arrangement is a byproduct of an unrelated design choice. The complaint shows a structural match but does not provide evidence regarding Tianma's manufacturing process or intent.

V. Key Claim Terms for Construction

’142 Patent: 'overlapped with the window-shaped opening part in a plan view' (Claim 1)

  • Context and Importance: This term describes the core structural relationship of the invention. The existence and nature of the 'overlap' is a dispositive issue for infringement. Practitioners may focus on this term because its interpretation will determine whether a mere geometric overlap is sufficient, or if a specific functional overlap is required.
  • Intrinsic Evidence for Interpretation:
    • Evidence for a Broader Interpretation: The claim language itself is purely geometric ('in a plan view'). Plaintiff may argue that any configuration where one opening is visibly superimposed over the other from a top-down perspective meets this limitation, regardless of the functional result.
    • Evidence for a Narrower Interpretation: The specification explicitly states that the overlap is configured to 'suppress the occurrence of the disclination' by preventing the electric field from forming an arc shape. (’142 Patent, col. 3:29-33). Defendant may argue that the term should be limited by this stated function, requiring an overlap that is specifically designed and sufficient to achieve this technical outcome.

’665 Patent: 'dummy pad group' (Claim 1)

  • Context and Importance: This term is central to the patent's solution for improving manufacturing reliability. Infringement hinges on whether the accused panels contain a set of pads that qualify as a 'dummy pad group.' Practitioners may focus on this term because the dispute will likely concern whether the definition is purely structural or also functional.
  • Intrinsic Evidence for Interpretation:
    • Evidence for a Broader Interpretation: The claim defines the group structurally as being 'composed of dummy pads' and 'disposed between the at least two connection pad groups.' The specification further clarifies that dummy pads are 'not connected to the connection wiring lines.' (’665 Patent, col. 5:11-14). Plaintiff could argue that any group of unconnected pads located between connection pad groups meets the claim.
    • Evidence for a Narrower Interpretation: The abstract and detailed description explain that the purpose of the dummy pads is to make 'the thermal distribution at the time of thermal press-bonding...uniform and defective connection can be prevented.' (’665 Patent, col. 5:48-51). Defendant could argue that a group of pads not intended for or not achieving this thermal management function is not a 'dummy pad group' within the meaning of the invention.

VI. Other Allegations

  • Indirect Infringement: The complaint alleges induced infringement for all three patents. The allegations state that Tianma sells the accused panels to downstream customers (e.g., Motorola, ASUS) with knowledge and intent that they will be incorporated into infringing end products sold in the U.S. The complaint further alleges affirmative steps such as establishing distribution channels and providing technical support. (Compl. ¶44, ¶60, ¶78).
  • Willful Infringement: Willfulness is alleged for all three patents. The basis for knowledge is pleaded as being 'at least as early as the filing date of the complaint,' indicating an allegation of post-filing willfulness. (Compl. ¶36, ¶59, ¶77).

VII. Analyst’s Conclusion: Key Questions for the Case

  • Structural Match vs. Functional Purpose: A core issue across the asserted patents will be whether showing a structural similarity is sufficient for infringement, or if the claims require proof that the accused structures perform the specific functions described in the patent specifications (e.g., suppressing disclination for the ’142 Patent, or ensuring uniform thermal bonding for the ’665 Patent). The case may turn on whether the court construes the claims as being limited to their stated functional context.
  • The Definition of “Dummy”: For the ’665 Patent, a key question for claim construction will be one of definitional scope: does the term "dummy pad group" refer to any group of electrically unconnected pads in the specified location, or is it limited to structures that are specifically designed to serve the thermal-management purpose described in the patent?
  • Evidentiary Burden for Overlap: For the ’142 Patent, the case will involve a key evidentiary question of functional proof: while the complaint's SEM images may show a geometric overlap between electrode layers, does this structural feature in the accused device function to control electric fields and prevent visual defects in the manner required by the patent, or is it an incidental artifact of a different, non-infringing design?