Hisense USA Corp v. Brightplus Ventures LLC

1. Case Identification

• Case #: IPR2023-01168
• Patent #: 9,605,835
• Filed: July 14, 2023
• Petitioner(s): Hisense USA Corporation
• Patent Owner(s): Brightplus Ventures LLC
• Challenged Claims: 1-5, 7-14

2. Patent Overview

• Title: Solid-State Luminaires for General Illumination
• Brief Description: The ’835 patent describes a lighting panel for general illumination, such as a backlight for an LCD display. The claimed panel includes a substrate with solid-state lighting devices (e.g., LEDs), a reflector, a brightness enhancement film (BEF), and a diffuser sheet positioned between the reflector and the BEF.

3. Grounds for Unpatentability

Ground 1: Obviousness over Mok, Holman, and Lamb - Claims 1-5 and 7-14

• Prior Art Relied Upon: Mok (Application # 2006/0227545), Holman (WO 03/056876), and Lamb (Application # 2005/0135115).
• Core Argument for this Ground:
  • Prior Art Mapping: Petitioner asserted that Mok was a suitable base reference, disclosing a light-emitting panel with the core claimed components: a substrate with LEDs, a reflector, a diffuser, and a BEF. Petitioner argued that Holman supplemented Mok by teaching a specific BEF arrangement positioned on a reflector sheet without an intervening air gap, allowing for a thinner panel. Petitioner further contended that Lamb explicitly taught the light recycling functionality of BEFs, wherein light of one orientation is transmitted while light of another is reflected back into the panel to be recycled, satisfying limitations regarding the preferential emission and reflection of light.
  • Motivation to Combine: Petitioner argued a person of ordinary skill in the art (POSITA) would combine these references to create a more efficient and thinner lighting panel. All three references are in the same field of LED backlighting and address common challenges of improving efficiency and light uniformity. Combining Holman’s thinner stacked design and Lamb’s efficient light recycling with Mok’s base panel was presented as a predictable application of known techniques to achieve a known goal.
  • Expectation of Success: A POSITA would have had a reasonable expectation of success because the combination involved applying known elements for their established functions to achieve predictable improvements in performance and form factor.

Ground 2: Obviousness over Epstein, Holman, and Lamb - Claims 1-5 and 7-14

• Prior Art Relied Upon: Epstein (Application # 2005/0265029), Holman (WO 03/056876), and Lamb (Application # 2005/0135115).
• Core Argument for this Ground:
  • Prior Art Mapping: Petitioner presented Epstein as an alternative base reference disclosing a backlight for an LCD with an array of LEDs on a substrate, a reflector layer, and BEFs. Similar to Ground 1, Petitioner argued Holman was used to teach a stacked BEF-on-reflector arrangement to achieve a thinner design, and Lamb was used to explicitly teach the light recycling capabilities of the BEF. Petitioner mapped Epstein’s disclosure of refracting light upon exiting a BEF as meeting the claim limitation of preferentially emitting light with a first orientation and reflecting light with a second orientation.
  • Motivation to Combine: The motivation was consistent with Ground 1: a POSITA would be driven to improve the efficiency and reduce the thickness of the lighting system described in Epstein. Petitioner contended that a POSITA would look to other references in the same field, like Holman and Lamb, for known solutions to achieve these common industry goals.
  • Expectation of Success: Petitioner asserted a high expectation of success, as the combination represented the integration of known, compatible components from the same technical field to predictably enhance a base system.

Ground 3: Obviousness over Ko, Kretman, and Epstein - Claims 1-5 and 7-14

• Prior Art Relied Upon: Ko (Application # 2006/0082698), Kretman (Application # 2003/0118805), and Epstein (Application # 2005/0265029).
• Core Argument for this Ground:
  • Prior Art Mapping: Petitioner asserted that Ko, which discloses a directly-illuminated LCD with light management layers including a diffuser, reflector, and BEF, served as the base reference. Kretman, which is explicitly incorporated by reference into Ko, was cited for its teachings on diffuse reflective materials and light recycling to increase luminance. Petitioner argued that Epstein supplemented Ko and Kretman by teaching a specific implementation of a planar array of LEDs on a substrate with an integrated reflector, which would be an obvious way to implement the light source in Ko’s system.
  • Motivation to Combine: Petitioner argued that an explicit motivation existed to combine Ko and Kretman, as Ko incorporates Kretman by reference. A POSITA would have been motivated to incorporate Epstein’s efficient LED array into Ko’s backlight system to improve its design, given that Ko discloses the use of LEDs as a possible light source. All three references share the common goal of improving the efficiency and quality of LED-based backlighting systems.
  • Expectation of Success: The combination was presented as predictable, as it involved incorporating a well-understood LED array configuration (Epstein) into a general backlight structure (Ko) that already contemplated using LEDs and incorporated advanced reflector technology (Kretman).

4. Arguments Regarding Discretionary Denial

• §325(d) Arguments: Petitioner argued that denial under 35 U.S.C. §325(d) was inappropriate because none of the prior art references asserted in the petition were cited in a rejection during the prosecution of the application that issued as the ’835 patent.
• §314(a) Fintiv Arguments: Petitioner argued that the Fintiv factors weigh against discretionary denial. It contended that the parallel district court litigation was in its early stages, with the counterclaim asserting the ’835 patent having been filed in September 2022 and no trial date set. Petitioner asserted that minimal investment had been made by the parties in the litigation and that a Final Written Decision from the PTAB would likely issue well before any potential trial date, favoring institution.

5. Relief Requested

• Petitioner requested institution of an inter partes review and cancellation of claims 1-5 and 7-14 of Patent 9,605,835 as unpatentable.