Samsung Electronics Co Ltd v. Polaris PowerLED Technologies LLC

1. Case Identification

• Case #: IPR2018-01262
• Patent #: 8,223,117
• Filed: June 15, 2018
• Petitioner(s): Samsung Electronics Co., Ltd., Samsung Electronics America, Inc., and Samsung Display Co., Ltd.
• Patent Owner(s): Polaris PowerLED Technologies, LLC
• Challenged Claims: 1-2, 4-7, 9, 13-16, 18-20

2. Patent Overview

• Title: Method and Apparatus to Control Display Brightness With Ambient Light Correction
• Brief Description: The ’117 patent discloses a brightness control circuit for a display that automatically adjusts brightness based on both a sensed ambient light signal and a user preference signal. The claimed invention features a "multiplier" to generate a combined signal from these inputs and a "dark level bias" to ensure the display maintains a minimum brightness level in low-light conditions.

3. Grounds for Unpatentability

Ground I: Claims 1-2, 4-7, 15-16, and 18-19 are obvious over Thayer in view of Godwin.

• Prior Art Relied Upon: Thayer (Patent 5,554,912) and Godwin (European Publication # 0570037).
• Core Argument for this Ground:
  • Prior Art Mapping: Petitioner argued that Thayer discloses a complete adaptive brightness control system for vehicle displays, including an ambient light sensor, a user input switch, and a microprocessor that uses a look-up table to determine brightness. Thayer also teaches maintaining a minimum brightness at near-zero ambient light, satisfying the "dark level bias" limitation. Petitioner asserted that Godwin, which addresses the same technical problem, teaches the specific improvement of using a multiplication algorithm to combine the user input and ambient light signals. This multiplication maintains a constant contrast ratio, a known benefit over Thayer’s look-up table approach.
  • Motivation to Combine: A POSITA would combine Godwin's multiplication algorithm with Thayer's foundational system to gain the recognized benefit of maintaining a constant, user-defined contrast ratio, which makes the display more consistently readable across all lighting conditions. The motivation is strengthened because both references are in the same technical field (automotive displays) and were developed by the same assignee (Delco Electronics Corporation).
  • Expectation of Success: A POSITA would have a high expectation of success, as the combination involves the predictable substitution of one known brightness calculation method (Godwin's multiplication) for another (Thayer's look-up table) within a well-understood system architecture.

Ground II: Claims 9 and 20 are obvious over Thayer, Godwin, and Toffolo.

• Prior Art Relied Upon: Thayer (Patent 5,554,912), Godwin (European Publication # 0570037), and Toffolo (Patent 6,337,675).
• Core Argument for this Ground:
  • Prior Art Mapping: This ground builds on the Thayer/Godwin combination to address claims 9 and 20, which add limitations for selectively operating in a manual or automatic mode. Petitioner argued that Toffolo explicitly teaches a display system with a switch (a multiplexer) that allows a user to select between an automatic brightness control mode (using an ambient light sensor) and a manual control mode (based solely on user input). In manual mode, the ambient light sensor is effectively disabled.
  • Motivation to Combine: A POSITA would be motivated to incorporate the manual/auto mode switch taught by Toffolo into the combined Thayer/Godwin system. This addition provides the well-known and desirable benefit of giving the user an option to override the automatic system, which was a recognized feature in the art for enhancing user control.
  • Expectation of Success: The integration would be a straightforward and predictable design choice, as adding a mode-selection switch to an existing brightness control system was a known technique.

Ground III: Claims 13 and 14 are obvious over Thayer, Godwin, and Morris.

• Prior Art Relied Upon: Thayer (Patent 5,554,912), Godwin (European Publication # 0570037), and Morris (Patent 6,657,663).
• Core Argument for this Ground:
  • Prior Art Mapping: This ground addresses claims 13 and 14, which recite a specific ambient light sensor comprising a full-spectrum PIN diode, an infrared-sensitive PIN diode, and an amplifier that generates a signal based on the difference between their outputs. Petitioner contended that Morris teaches this exact sensor architecture to create a more accurate visible light signal by subtracting out infrared (IR) noise. For claim 14, which adds a low-pass filter, Petitioner pointed to Godwin, which teaches filtering the sensor signal to dampen its response to transient light changes (e.g., driving under trees) and prevent display flickering.
  • Motivation to Combine: A POSITA would substitute the basic ambient light sensors of Thayer and Godwin with the superior sensor taught by Morris to solve the known problem of IR radiation from artificial lighting (e.g., headlights, streetlights) corrupting the ambient light reading and causing inaccurate brightness adjustments. Applying Godwin's filtering technique is a logical next step to improve system stability.
  • Expectation of Success: Success would be highly predictable, as this combination involves replacing a standard component with a known, improved version (Morris's sensor) to solve a recognized problem in the field (IR interference), and applying a known filtering technique for its established purpose.

4. Key Claim Construction Positions

• For the purpose of the IPR, Petitioner stated it adopted the Patent Owner's constructions from parallel district court litigation.
• "a multiplier configured to selectively generate a combined signal...": This term was construed to encompass hardware or software that generates a combined signal based on both a user input and a sensing signal from an ambient light sensor.
• "a dark level bias configured to adjust the combined signal...": This term was construed to encompass software (e.g., a software variable) used to adjust the brightness control signal to ensure it is maintained above a predefined minimum level when the ambient light level decreases to approximately zero.

5. Arguments Regarding Discretionary Denial

• Petitioner argued that discretionary denial under 35 U.S.C. § 325(d) would be inappropriate.
• The argument was based on the fact that none of the primary prior art references relied upon in the petition (Thayer, Godwin, Toffolo, and Morris) or the specific combinations and arguments asserted were considered by the USPTO examiner during the original prosecution of the ’117 patent.

6. Relief Requested

• Petitioner requests institution of an inter partes review and cancellation of claims 1-2, 4-7, 9, 13-16, and 18-20 of the ’117 patent as unpatentable.