Patents by Inventor David A. Waldman

David A. Waldman has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Publication number: 20020197440
    Abstract: An apparatus and method that produces recording media using at least two platens. A first platen is movable relative to a second platen, and each platen has respective first and second support surfaces onto which substrates are placed, the first and second substrates each having inner and outer longitudinal surfaces. A centering device aligns the respective substrates relative to a one or more reference positions, a positioning system provides a degree of parallelism between the outer longitudinal surfaces of each of the substrates and produces a desired gap between the inner longitudinal surfaces of the substrates, and a dispensing unit which emits a liquid medium within the gap between inner longitudinal surfaces of the substrates.
    Type: Application
    Filed: May 14, 2002
    Publication date: December 26, 2002
    Applicant: Aprilis, Inc.
    Inventors: David A. Waldman, Rod Hopwood, Richard T. Ingwall, YajPaul Panchu
  • Publication number: 20020198955
    Abstract: A hybrid data storage system that includes a controller that communicates with an outside source of information, and at least one holographic drive engine that communicates with controller. The information is transmitted between the controller and the outside source of information and between the holographic drive engine and the controller.
    Type: Application
    Filed: April 4, 2002
    Publication date: December 26, 2002
    Applicant: Aprilis, Inc.
    Inventors: David A. Waldman, Richard T. Ingwall, M. Glenn Horner
  • Publication number: 20020068223
    Abstract: Disclosed is a holographic recording medium. The novel holographic recording mediums disclosed herein comprises: a) at least one polyfunctional epoxide monomer or oligomer which undergoes acid initiated cationic polymerization. Each epoxide in the monomer or oligomer is linked by group comprising a siloxane to a silicon atom and each monomer or oligomer has an epoxy equivalent weight of greater than about 300 grams/mole epoxide; b) a binder which is capable of supporting cationic polymerization; c) an acid generator capable of producing an acid upon exposure to actinic radiation; and optionally d) a sensitizer.
    Type: Application
    Filed: August 28, 2001
    Publication date: June 6, 2002
    Applicant: Aprilis, Inc.
    Inventors: Erdem A. Cetin, Richard A. Minns, David A. Waldman
  • Patent number: 5759721
    Abstract: A holographic recording medium comprises an acid generator capable of producing an acid upon exposure to actinic radiation; a binder; and at least one monomer or oligomer capable of undergoing cationic polymerization initiated by the acid produced from the acid generator. This recording medium is not subject to the disadvantages (for example, oxygen sensitivity) associated with radical-polymerized prior art holographic recording media.
    Type: Grant
    Filed: November 1, 1996
    Date of Patent: June 2, 1998
    Assignee: Polaroid Corporation
    Inventors: Pradeep K. Dhal, Michael G. Horner, Richard T. Ingwall, Eric S. Kolb, Parag G. Mehta, Richard A. Minns, Howard G. Schild, David A. Waldman
  • Patent number: 5721630
    Abstract: A high-efficiency holographic diffuser is provided, the holographic diffuser being comparatively thin, yet characterized by good optical density along a broad bandwidth.
    Type: Grant
    Filed: March 12, 1996
    Date of Patent: February 24, 1998
    Assignee: Polaroid Corporation
    Inventors: M. Glenn Horner, David A. Waldman
  • Patent number: 5460860
    Abstract: Mesogen containing biaxially oriented films are prepared from curable mixtures containing an epoxy resin and a curing agent therefor. Certain of the mesogen containing biaxially oriented films possess unique properties, such as a metallic like, highly reflective appearance. These films are useful in adhesives, coatings, laminates or composites and the like.
    Type: Grant
    Filed: May 20, 1994
    Date of Patent: October 24, 1995
    Assignee: The Dow Chemical Company
    Inventors: Robert E. Hefner, Jr., Jimmy D. Earls, Peter E. Pierini, David A. Waldman, Lalitha Reddy
  • Patent number: 4378486
    Abstract: A temperature controlled timer useful for controlling the application of power to apparatus such as automobile block heaters or the like. In one embodiment the time of application of power prior to a shut off time is decreased with increasing ambient temperature. In another embodiment the duty cycle of cyclically applied power is changed so that the power on period becomes shorter and the power off period becomes longer with increasing ambient temperature. Significant conservation of power results.
    Type: Grant
    Filed: December 29, 1980
    Date of Patent: March 29, 1983
    Assignee: The Conserver Group Inc.
    Inventors: Maurice Yunik, David Waldman