MianYang BOE OptoelecTronics Technology Co Ltd v. SamSung DisPlay Co Ltd

1. Case Identification

• Case #: IPR2023-00987
• Patent #: 9,818,803
• Filed: June 21, 2023
• Petitioner(s): Mianyang BOE Optoelectronics Technology Co., Ltd.; Wuhan China Star Optoelectronics Semiconductor Display Technology Co., Ltd.; Tianma Microelectronics Co. Ltd.; and Visionox Technology, Inc.
• Patent Owner(s): Samsung Display Co., Ltd.
• Challenged Claims: 1-5 and 19-21

2. Patent Overview

• Title: Pixel Arrangement Structure for Organic Light Emitting Display Device
• Brief Description: The ’803 patent describes a pixel arrangement for an organic light emitting diode (OLED) display. The arrangement uses a repeating "virtual square" unit cell containing red, green, and blue pixels, where a green pixel is at the center and red and blue pixels are at the vertices, with specific relative sizing to improve display life.

3. Grounds for Unpatentability

Ground 1: Claims 1-5 and 19-21 are obvious over Matthies in view of Yamada.

• Prior Art Relied Upon: Matthies (Patent 6,897,855) and Yamada (Patent 6,366,025).
• Core Argument for this Ground:
  • Prior Art Mapping: Petitioner argued that Matthies taught an OLED display with a "quad sub-pixel structure" comprising red, green, and blue pixels arranged in a repeating square matrix that satisfies the "virtual square" layout of claim 1. However, Matthies disclosed equally sized pixels. Petitioner asserted that Yamada addressed the known problem of OLED deterioration by teaching the resizing of pixels based on their emission efficiency—specifically, making the least efficient blue pixel largest and the most efficient green pixel smallest to prolong display life. Applying Yamada's explicit resizing ratio to Matthies' square pixel layout allegedly rendered all limitations of the challenged claims obvious.
  • Motivation to Combine: A POSITA would combine these references to solve the well-known problem of differential aging in OLED displays, a problem Matthies acknowledged. Yamada provided a known, simple solution (pixel resizing) to improve display life and simplify control circuitry, which was an express goal of Matthies (reducing manufacturing costs). Petitioner contended that Matthies itself invited such modification by recognizing that pixel geometry affects the "rate of decay" and could be adjusted.
  • Expectation of Success: A POSITA would have had a reasonable expectation of success because resizing pixels was a routine design modification to improve OLED lifetime. Both references are directed to OLED display technology, making the combination of their respective teachings predictable and straightforward.

Ground 2: Claims 1-4 and 19-21 are obvious over Phan.

• Prior Art Relied Upon: Phan (Patent 7,091,986).
• Core Argument for this Ground:
  • Prior Art Mapping: Petitioner contended that Phan, by itself, rendered most of the challenged claims obvious. Phan taught an OLED display with red, green, and blue dots arranged in a repeating "square quad pixel" grid. This arrangement, when tiled, allegedly formed the claimed "virtual square" with a green dot at its center. Critically, Petitioner pointed to Phan's Figure 11b, which disclosed a variation where a shifted crosspoint resulted in dots of non-equal areas, specifically teaching a larger blue dot ("second pixel") relative to the red and green dots, satisfying the size limitation of claim 1.
  • Motivation to Combine (for §103 grounds): As this ground relied on a single reference, the argument focused on the explicit teachings within Phan. Petitioner argued a POSITA would find it obvious to implement the disclosed pixel arrangements, including the embodiment with variably sized pixels, to achieve the benefits of higher resolution described in Phan.

Ground 3: Claims 1-5 and 19-21 are obvious over Murai in view of Yamada.

• Prior Art Relied Upon: Murai (JP 4496852) and Yamada (Patent 6,366,025).
• Core Argument for this Ground:
  • Prior Art Mapping: Petitioner argued that Murai taught a color OLED display with red, green, and blue pixels arranged in a square grid, forming the claimed "virtual square." Murai also taught adjusting pixel sizes by using corner "cut-offs." In one embodiment (Fig. 3), Murai's green pixels were already smaller than its red and blue pixels due to having more cut-offs. Petitioner asserted that to meet the claim 1 limitation requiring the blue pixel to be larger than the red pixel, a POSITA would have applied the teachings of Yamada. This would involve modifying Murai’s cut-off method according to Yamada's resizing principles to make the blue pixel largest, red intermediate, and green smallest.
  • Motivation to Combine: The motivation was similar to that for combining Matthies and Yamada. A POSITA would have been motivated to apply Yamada’s known solution for improving display life to Murai’s display structure. Murai already taught size differentiation to improve image quality, so using that mechanism to also improve display life, as taught by Yamada, would have been a natural and obvious extension.
  • Expectation of Success: A POSITA would have expected success because both references concerned pixel designs for OLED displays. Combining Murai's layout and size-adjustment mechanism with Yamada's well-known resizing principle was presented as a predictable combination of known elements to achieve an expected result.
• Additional Grounds: Petitioner asserted an additional ground that claim 5 is obvious over Phan in view of Yamada. This ground argued that while Phan teaches a larger blue pixel, it does not explicitly teach that the red pixel is also larger than the green pixel. A POSITA would have applied Yamada's resizing principles to Phan to achieve this, thereby rendering claim 5 obvious.

4. Arguments Regarding Discretionary Denial

• §314(a) (Fintiv): Petitioner argued that a pending related ITC matter should have no bearing on the Board's decision to institute, citing the Board's June 2022 Interim Procedure for Discretionary Denials.
• §325(d): Petitioner argued that denial under §325(d) would be inappropriate because the petition raised new arguments based on prior art that was not considered during prosecution. Specifically, Matthies, Phan, and Murai were never before the Examiner. Although Yamada was cited on the face of the ’803 patent, it was not substantively discussed or used in any rejection. Petitioner contended this new art is substantively different and overcomes deficiencies the Examiner identified in the previously considered art.

5. Relief Requested

• Petitioner requests institution of an inter partes review and cancellation of claims 1-5 and 19-21 of Patent 9,818,803 as unpatentable.