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 in response to ambient light conditions and user preferences. The core technology involves a "multiplier" that combines a user signal with an ambient light sensor signal, and a "dark level bias" to ensure the display maintains a minimum brightness level in low-light environments.

3. Grounds for Unpatentability

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

• Prior Art Relied Upon: Thayer (Patent 5,554,912) and Godwin (European Patent Office Publication No. 0050037).
• Core Argument for this Ground:
  • Prior Art Mapping: Petitioner argued that Thayer discloses a complete adaptive brightness control system for vehicle displays, including a user input (control switch), an ambient light sensor, and a microprocessor that uses a look-up table to determine brightness. Thayer also teaches maintaining a minimum brightness level, even at zero ambient light, which corresponds to the claimed "dark level bias." While Thayer teaches combining user and sensor inputs, Godwin explicitly discloses the claimed "multiplier" function: multiplying a user-inputted contrast ratio signal with a sensed ambient light signal to calculate the desired display brightness. Petitioner asserted that the combination of Thayer's overall system with Godwin's specific multiplication algorithm renders the independent claims obvious. Dependent claims are addressed by two different, obvious ways of incorporating the minimum brightness feature (the "dark level bias") into Godwin's multiplication algorithm.
  • Motivation to Combine: A Person of Ordinary Skill in the Art (POSA) would combine Godwin's multiplication algorithm with Thayer's system to achieve a known benefit: maintaining a constant, user-desired contrast ratio for better readability in all light conditions, as expressly taught by Godwin. This represents a simple substitution of one known brightness calculation method (Thayer's look-up table) for an improved one (Godwin's multiplication), yielding predictable results. The motivation is strengthened because both references originated from the same assignee (Delco Electronics) and address the same technical problem in vehicle displays.
  • Expectation of Success: A POSA would have a high expectation of success, as integrating Godwin's multiplication software routine into the microprocessor of Thayer's system is a straightforward application of a known technique to a similar system to achieve a predictable improvement.

Ground II: Obviousness over Thayer, Godwin, and Toffolo - Claims 9 and 20 are obvious over Thayer and Godwin in view of Toffolo.

• Prior Art Relied Upon: Thayer (Patent 5,554,912), Godwin (European Patent Office Publication No. 0050037), and Toffolo (Patent 6,337,675).
• Core Argument for this Ground:
  • Prior Art Mapping: This ground builds on the combination of Thayer and Godwin to address claims 9 and 20, which add the limitation of a system that can switch between a manual mode and an automatic mode, where the ambient light sensor is disabled in manual mode. Petitioner contended that Toffolo explicitly teaches this functionality. Toffolo discloses a display system with both "automatic and manual brightness control" modes and a switch (multiplexer) that allows a user to select between them. In Toffolo's automatic mode, brightness is based on an ambient light sensor; in manual mode, it is based solely on user input, rendering the sensor's input unnecessary and effectively disabled for the brightness calculation.
  • Motivation to Combine: A POSA would be motivated to incorporate Toffolo's manual/auto switch into the combined Thayer/Godwin system to provide the user with the well-known and desirable option of manual control. Providing this choice was a known method for improving user satisfaction with automatic systems.
  • Expectation of Success: The combination would have yielded predictable results, as it involves adding a known feature (a mode switch) to a known system (an automatic brightness controller) to gain a known benefit (user choice). All three references are in the same field of vehicle display controls.

Ground III: Obviousness over Thayer, Godwin, and Morris - Claims 13 and 14 are obvious over Thayer and Godwin in view of Morris.

• Prior Art Relied Upon: Thayer (Patent 5,554,912), Godwin (European Patent Office Publication No. 0050037), and Morris (Patent 6,657,663).
• Core Argument for this Ground:
  • Prior Art Mapping: This ground addresses claims 13 and 14, which relate to a specific light sensor construction. Claim 13 recites a sensor with a full-spectrum PIN diode and an infrared-sensitive PIN diode, where the final sensing signal is generated by subtracting one output from the other to filter out infrared (IR) light. Petitioner asserted that Morris discloses this exact sensor structure. Claim 14 adds a low-pass filter to reduce sensitivity to transient light variations, which Petitioner contended is taught by Godwin's disclosure of filtering the sense signal to prevent flickering.
  • Motivation to Combine: A POSA would substitute the basic ambient light sensors of Thayer/Godwin with the advanced IR-filtering sensor from Morris. The motivation is to solve a known problem in automotive applications: artificial lighting and sunlight emit high levels of IR that can cause erroneous brightness adjustments. Morris expressly teaches its sensor design to create a more accurate representation of visible light. A POSA would also incorporate Godwin's filtering technique as a known solution to the separate, known problem of transient light changes (e.g., driving under trees).
  • Expectation of Success: This would be a simple substitution of a superior, known component (Morris's sensor) into an existing system (Thayer/Godwin) to achieve the predictable benefit of improved accuracy in environments with high IR interference.

4. Key Claim Construction Positions

• For the purposes of the IPR, Petitioner adopted the Patent Owner's claim constructions from related district court litigation. This was done to streamline the IPR proceeding without conceding the correctness of the constructions for litigation. Key adopted constructions include:
• "multiplier..." (claims 1, 15, 19): Encompasses hardware or software for generating a combined signal from both a user input and a sensing signal.
• "dark level bias..." (claims 1, 15, 19): Encompasses a software variable used to adjust a combined signal to maintain brightness above a predetermined level when ambient light approaches zero.

5. Arguments Regarding Discretionary Denial

• Petitioner argued that discretionary denial under §325(d) would be inappropriate. It contended that the grounds presented in the petition are not the same or substantially the same as prior art or arguments previously considered by the PTO during prosecution. None of the primary references (Thayer, Godwin, Toffolo, Morris) or the specific combinations were before the examiner.

6. Relief Requested

• Petitioner requested 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.