PTAB

IPR2015-01113

Mercedes Benz USA LLC v. Innovative Display Technologies

Key Events

Petition

petition

Title: Light Emitting Panel Assemblies
Brief Description: The ’660 patent discloses light emitting panel assemblies designed to efficiently conduct and control light for illuminating displays, such as LCDs. The technology uses a transparent panel member with features like surface deformities to direct light from one or more sources to desired output areas.

Prior Art Relied Upon: Pristash (Patent 5,005,108).
Core Argument for this Ground:
- Prior Art Mapping: Petitioner argued that Pristash, which discloses a "thin panel illuminator," teaches every element of the challenged claims. Specifically, Pristash discloses a light emitting panel assembly with a planar optical conductor, an output region with a pattern of deformities (prism ridges), and a transition region between the light source and the output region. The key limitation requiring "a plurality of light sources configured to generate light having an output distribution defined by a greater width component than height component" was allegedly met by Pristash’s disclosure of a light source arranged with transition devices (e.g., collectors and reflectors) that collectively shape the light output into the required wider-than-tall distribution before it enters the panel.
- Key Aspects: This ground relied on a construction where the "configured" limitation can be satisfied by the light sources in combination with other elements, such as reflectors.

Prior Art Relied Upon: Ciupke (Patent 5,461,547).
Core Argument for this Ground:
- Prior Art Mapping: Petitioner asserted that Ciupke, which was not cited during prosecution, discloses all elements of these claims. Ciupke describes a lighting system for flat panel displays using a light guide with microgrooves (deformities) to extract light. Petitioner contended Ciupke met the "configured" light source limitation by disclosing a light source combined with a U-shaped reflector that generates an output distribution with a greater width than height. Ciupke also explicitly taught using a plurality of light sources.
- Key Aspects: Similar to Ground 1, this anticipation argument depended on the light source being "configured" in combination with an external element (a reflector) to achieve the claimed output distribution.

Prior Art Relied Upon: Pristash (Patent 5,005,108) and Kisoo (Japanese Application Publication No. 06-230378).
Core Argument for this Ground:
- Prior Art Mapping: This ground provided an alternative basis for claims 1-17 and addressed the additional limitations of claims 25, 33, and 34. Petitioner argued that Kisoo, an LED backlighting apparatus, supplied the elements that Pristash lacked. Specifically, Kisoo taught a plurality of rectangular-shaped LEDs where each light source individually has a greater width than height, directly teaching the limitation of claims 33 and 34. Kisoo also disclosed placing the light emitting panel within a tray, satisfying claim 25.
- Motivation to Combine: A POSITA would combine Pristash and Kisoo because both references address the same problem of LCD backlighting with similar device structures. Pristash explicitly suggested using alternative light sources, including LEDs, making the rectangular LEDs from Kisoo a natural and predictable substitution to achieve a desired light shape. The use of a tray from Kisoo was argued to be a well-known method for providing structural support.
- Expectation of Success: Combining the known elements would have yielded predictable results for improving backlight assemblies.

Prior Art Relied Upon: Ciupke (Patent 5,461,547) and Seraku (Japanese Application Publication No. 05-69732).
Core Argument for this Ground:
- Prior Art Mapping: This ground asserted that Seraku remedied any deficiencies in Ciupke. Seraku disclosed a backlighting structure with rectangular-shaped LEDs that individually generate a light output with a greater width than height, satisfying the limitations of claims 33 and 34. Seraku also taught receiving the light emitting panel in a reflecting case or tray, meeting the limitation of claim 25.
- Motivation to Combine: A POSITA would combine these references because Ciupke suggested using alternative light sources that "direct light into the light pipe," and Seraku’s LEDs were an effective and well-known option for doing so. Both references describe similar backlighting assemblies for flat panel displays, and substituting Seraku's LEDs and tray into Ciupke's system was presented as an obvious design choice to improve performance and simplify construction.
- Expectation of Success: The combination was a predictable implementation of known technologies to achieve a better-performing backlight.

"a plurality of light sources configured to generate light having an output distribution defined by a greater width component than height component": Petitioner proposed this key limitation from claim 1 should be construed to mean the light sources are configured either individually or in combination with other elements (like reflectors or transition areas) to generate the specified light output. This broad construction was central to the anticipation arguments in Grounds 1 and 2, where reflectors in the prior art were used to shape the light. Petitioner contrasted this with claim 33, which requires each light source to be so configured, arguing this distinction supports a broader reading for claim 1.
"deformities": Petitioner proposed this term be construed as "change[s] in the shape or geometry of the panel surface and/or coating or surface treatment that causes a portion of the light to be emitted," consistent with its definition in the ’660 patent’s specification.
"focused light sources": Petitioner argued this term from claims 16 and 17 should be construed to encompass at least LED light sources, as indicated by the dependency of claim 17 (requiring LEDs) on claim 16.

Petitioner requested institution of an inter partes review and cancellation of claims 1, 3, 10, 16, 17, 25, 33, and 34 of the ’660 patent as unpatentable.