“Highly Modulated Surface” Renders Claim Indefinite

The court granted defendants' motion for summary judgment of invalidity for indefiniteness of plaintiff's optical diffuser patent following claim construction. "The [patent-in-suit] fails to provide a standard for measuring the difference between a mere modulated surface and a highly modulated surface. In fact, the patent provides conflicting descriptions of the kinds of bumps that comprise a highly modulated surface. . . . As such, the patent fails to provide a person of ordinary skill in the art an objective anchor against which a potentially infringing product may be compared to determine whether the product meets the highly modulated limitation of Claim 1. . . . While [plaintiff] identifies an alleged purpose of a 'highly' modulated surface as being one of hiding structural features of the light source, the specification instead describes that feature only as a potential use of the surface as a component in an LCD display. . . . A potential use is not a purpose. Accordingly, [plaintiff's] attempt to divine objective guidance from the specification via expert testimony does not save the claims from a finding of indefiniteness."

Advanced Display Technologies of Texas, LLC v. AU Optronics Corporation, et. al., 6-11-cv-00011 (TXED July 12, 2012, Order) (Davis, J.).