Patents Assigned to Coho Holdings LLC
  • Patent number: 8187481
    Abstract: A surface relief structure consisting of a random distribution of surface features with varying feature profile and depth, is described. The texture serves to suppress the reflection of electromagnetic waves in the optical region of the spectrum without dispersing any portion of the spectrum by diffraction. Processes for fabricating the random distribution anti-reflecting textures in common materials are also described. The disclosed textures are particularly useful as anti-reflecting covers for displays, and as directly molded anti-reflecting surfaces in eyeglass lenses. Other applications such as covers for artwork, and improved solar cells are made practical by the invention.
    Type: Grant
    Filed: May 5, 2006
    Date of Patent: May 29, 2012
    Assignee: Coho Holdings, LLC
    Inventor: Douglas S. Hobbs
  • Patent number: 7304775
    Abstract: An interference lithography system is described that is capable of exposing high resolution patterns in photosensitive media and employing yield increasing active stabilization techniques needed in production environments. The inventive device utilizes a division-of-wavefront interference lithography configuration which divides a single large field size optical beam using one or more mirrors, and is actively stabilized with a subsystem employing; a phase modulator operating on each divided wavefront section; a novel feedback apparatus for observing the relative phase shifts between interfering wavefront sections; and a control system for holding the relative phase shifts constant.
    Type: Grant
    Filed: March 2, 2001
    Date of Patent: December 4, 2007
    Assignee: CoHo Holdings, LLC
    Inventors: Douglas S. Hobbs, James J. Cowan
  • Patent number: 6870624
    Abstract: An apparatus for filtering electromagnetic waves, the apparatus comprising a substrate having a surface relief structure containing at least one dielectric body with physical dimensions smaller than the wavelength of the filtered electromagnetic waves, such structures repeated in a two dimensional array covering at least a portion of the surface of the first substrate. Also disclosed is a material sensor utilizing this apparatus.
    Type: Grant
    Filed: October 30, 2001
    Date of Patent: March 22, 2005
    Assignee: Coho Holdings LLC
    Inventors: Douglas S. Hobbs, James J. Cowan
  • Patent number: 6791757
    Abstract: An apparatus for filtering electromagnetic waves and sensing deposition of chemical species, the apparatus having a substrate having a surface relief structure containing at least one dielectric body with physical dimensions smaller than the wavelength of the filtered electromagnetic waves, such structures repeated in a two dimensional array covering at least a portion of the surface of the first substrate. The apparatus may include one, two, or more such arrays, spaced from one another to create one or more cavities between the arrays.
    Type: Grant
    Filed: August 6, 2002
    Date of Patent: September 14, 2004
    Assignee: CoHo Holdings, LLC
    Inventors: Douglas S. Hobbs, James J. Cowan
  • Patent number: 6707518
    Abstract: Surface textures embossed in a substrate such as plastic include surface depressions or cones having equally-spaced, reflective terraced steps to support coherent reflections of incident light. A desired color or bandwidth of coherent reflected light off the terraced steps is produced by adjusting the index of refraction of a material in communication with the terraced steps of the substrate. Preferably, the index of refraction of each zone of terraced steps is controlled based on an applied electric field. Accordingly, light reflected from a plurality of controlled zones can be used to produce an image for an observer.
    Type: Grant
    Filed: July 12, 2000
    Date of Patent: March 16, 2004
    Assignee: CoHo Holdings, LLC
    Inventor: James J. Cowan