PTAB

IPR2013-00611

Samsung Electronics America Inc v. LED Tech Development LLC

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Petition
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1. Case Identification

2. Patent Overview

  • Title: Color-Adjusted Camera Light and Method
  • Brief Description: The ’390 patent discloses an LED illumination source and methods for illuminating a scene. The system maintains a constant light output characteristic, such as brightness or color, by selectively applying power pulses to the LEDs and adjusting the pulse width, frequency, or height based on a feedback signal corresponding to battery voltage or ambient light.

3. Grounds for Unpatentability

Ground 1: Anticipation of Claims 19, 22, 24, 25, and 29-32 under 35 U.S.C. §102

  • Prior Art Relied Upon: Van Antwerp (Patent 4,514,727).
  • Core Argument for this Ground:
    • Prior Art Mapping: Petitioner argued that Van Antwerp, which discloses an automatic brightness control circuit for an automotive LED display, teaches every limitation of the challenged claims. Van Antwerp describes a control circuit that adjusts the pulse width (on-time proportion) supplied to LEDs to maintain constant brightness. This adjustment is made in response to feedback from both ambient light sensors and declining battery voltage. Petitioner asserted this is identical to the ’390 patent’s method, where a drop in battery voltage (pulse height) triggers an increase in pulse width to maintain a constant light output.
    • Key Aspects: The core of this ground was that Van Antwerp’s circuit, which uses a 555-type timer for pulse width modulation in response to voltage changes, is functionally and structurally identical to the circuit described in the ’390 patent for the same purpose.

Ground 2: Claims 1-4, 6, 11-14, 16, 20, 27, and 34-38 are obvious over Garriss in View of Van Antwerp

  • Prior Art Relied Upon: Garriss (Patent 5,010,412) and Van Antwerp (Patent 4,514,727).
  • Core Argument for this Ground:
    • Prior Art Mapping: Petitioner asserted that Garriss discloses the base system: a portable video camera with an attached LED flash assembly. The brightness in Garriss is controlled by manually adjusting the frequency and duty cycle of power pulses. However, Garriss lacks an automatic feedback mechanism. Van Antwerp was argued to supply this missing element by teaching an automatic brightness control circuit for LED displays that uses a feedback signal based on ambient light to adjust the pulse width.
    • Motivation to Combine: A Person of Ordinary Skill in the Art (POSITA) would combine these references to replace the manual brightness control in Garriss with the superior automatic control from Van Antwerp. Both references address LED lighting, and Van Antwerp stated its invention had general applicability beyond automotive displays. The combination would solve the known problem of maintaining consistent illumination for a video camera light under varying ambient light conditions, a clear and predictable improvement.
    • Expectation of Success: A POSITA would have a high expectation of success, as incorporating Van Antwerp's known feedback control circuit into Garriss's LED driver circuit involved applying a known technique to a similar problem to yield a predictable result.

Ground 3: Claims 1, 3, 4, 6, 11, 13, 14, 16, 19, 20, 22, 24, 25, 27, 29, 31, 32, 34, 35, 37, and 38 are obvious over Garriss in view of Mallory

  • Prior Art Relied Upon: Garriss (Patent 5,010,412) and Mallory (Patent 4,499,525).

  • Core Argument for this Ground:

    • Prior Art Mapping: As in Ground 2, Garriss provided the base system of a video camera with a manually controlled LED light. Petitioner argued that Mallory supplied the teachings for automatic compensation for declining battery voltage. Mallory describes a circuit for a battery-powered flashlight that senses dropping battery voltage and uses that feedback to automatically increase the pulse width of power supplied to the lamp, thereby maintaining constant brightness.
    • Motivation to Combine: A POSITA would be motivated to combine Mallory’s battery compensation circuit with Garriss’s LED light to improve its performance as the battery drains. Both references relate to portable, battery-powered lights. Although Mallory discloses an incandescent bulb, Petitioner argued its circuit was equally applicable to LEDs, a simple and known substitution at the time. This combination would improve Garriss by obviating the need for a separate voltage regulator.
    • Expectation of Success: Success was predictable because the combination involved integrating a known automatic power adjustment circuit (Mallory) into a standard LED illumination system (Garriss) to solve the common problem of battery drain.

  • Additional Grounds: Petitioner asserted additional obviousness challenges (Ground 4) for claims requiring adjustment of pulse frequency. These grounds were based on Garriss in view of either Mallory or Van Antwerp, and further in view of Hochstein (Patent 5,783,909). Hochstein was cited for its explicit teaching that pulse width modulation and pulse frequency modulation were well-known and interchangeable techniques for controlling current to LEDs.

4. Key Claim Construction Positions

  • "feedback [signal]": Petitioner argued this term should be broadly construed to include any signal "influenced by present operating circumstances, such as battery voltage or ambient light." This construction was central to mapping the teachings of Van Antwerp and Mallory, which use these parameters as feedback inputs to their control circuits.
  • "adjusts a height of the pulses to control a color spectrum": Petitioner contended that because the relationship between current (related to pulse height) and LED color spectrum was admitted in the ’390 patent as known prior art, any circuit that adjusted pulse height inherently and necessarily controlled the color spectrum. This interpretation allowed Petitioner to argue that prior art circuits which adjusted pulse height in response to battery voltage inherently met this limitation.

5. Relief Requested

  • Petitioner requested the institution of an inter partes review and the cancellation of claims 1-6, 9-16, and 19-39 of the ’390 patent as unpatentable.