Patents by Inventor David N. Pulsifer

David N. Pulsifer 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).

  • Patent number: 5673353
    Abstract: A fiber preform structure, preferably of an optical glass for use in making fibers and lenses, constructed with a central core of a first material, a surrounding tube of a second material, and a deeply placed bonded layer integrally formed between the core and tube preferably by a heat driven interdiffusion of the first and second materials. The deeply placed interface layer of the resulting preform structure exhibits material characteristics related to the interdiffused material characteristics of the rod and tube materials. The interdiffusion is preferably performed while supporting the combined rod and tube structure. The preform is rotated during heating to maintain the geometric symmetry of the preform and of the interface layer. An encapsulating carrier is used to support the preform in all dimensions during heating.
    Type: Grant
    Filed: June 7, 1995
    Date of Patent: September 30, 1997
    Inventors: Robert M. Ward, David N. Pulsifer
  • Patent number: 5522003
    Abstract: A glass preform structure, preferably of an optical glass, constructed with a central core of a first material, a surrounding tube of a second material, and a deeply placed bonded layer integrally formed between the core and tube preferably by a heat driven interdiffusion of the first and second materials. The deeply placed interface layer of the resulting preform structure exhibits material characteristics related to the interdiffused material characteristics of the rod and tube materials. The interdiffusion is preferably performed while supporting the combined rod and tube structure. The preform is rotated during heating to maintain the geometric symmetry of the preform and of the interface layer. An encapsulating carrier is used to support the preform in all dimensions during heating.
    Type: Grant
    Filed: March 2, 1993
    Date of Patent: May 28, 1996
    Inventors: Robert M. Ward, David N. Pulsifer
  • Patent number: 5200858
    Abstract: Tailored glass bodies (10) having a substantial change in index of refraction (a .DELTA.n of at least about 0.08 along an axis) are provided. The glass body is characterized by two substantially parallel surfaces, with one surface having a first composition (12t) and the other surface a second composition (12b). The composition of the glass body varies in some predetermined fashion between the two surfaces (12i1-12i8) to provide a predetermined graded index of refraction. A method is also provided to tailor the glass body so that the two compositions have one or more of the following properties substantially constant: thermal coefficient of expansion, glass fusion temperature, Abbe value, and density.
    Type: Grant
    Filed: May 11, 1992
    Date of Patent: April 6, 1993
    Assignee: LightPath Technologies, Inc.
    Inventors: James J. Hagerty, David N. Pulsifer, Guy E. Rindone
  • Patent number: 4929065
    Abstract: A glass block (10) comprises a plurality of intermediate glass plates (12i) stacked between a top plate (12t) and a bottom plate (12b). The top and bottom plate each have a selected composition, with a particular index of refraction and a softening temperature. The intermediate plates have compositions intermediate those of the top and bottom plates and are stacked so as to provide a gradient in composition from top to bottom. Heating the assembly at a fusion temperature fuses the plates together to form the glass block. After cooling down to room temperature, the glass block can be shaped to make lenses and other light directing devices. Such lenses have a gradient in the refractive index of at least about 0.085, and gradients approaching 0.5 are achievable. The thickness of the glass block along the optic axis is fairly unlimited, and thicknesses on the order of 10 mm and more are routinely achievable by the process of the invention.
    Type: Grant
    Filed: November 3, 1988
    Date of Patent: May 29, 1990
    Assignee: ISOTEC Partners, Ltd.
    Inventors: James J. Hagerty, David N. Pulsifer
  • Patent number: 4516281
    Abstract: A sewage treatment device [10] is disclosed for use with a toilet [12] having a water flush input [16] and a sewage output [22]. The invention incorporates a treatment tank [56] connected for receiving the sewage from the sewage output [22] of the toilet. A disinfectant holding tank [58] is included for holding a disinfectant such as conventional household bleach. A mascerator blade [74] is disposed within the treatment tank [56] for mascerating the sewage to reduce the size of the particulate matter within the treatment tank [56]. An electric motor rotates the mascerator blade [74] and simultaneously pumps a disinfectant from the disinfectant holding tank [58] to the treatment tank [56]. A discharge pump [86] discharges the treated sewage from the treatment tank [56]. A control senses the level of the sewage in the sewage treatment tank and controls the sequence of operation of the mascerator blade [74] and the discharge pump [86].
    Type: Grant
    Filed: May 11, 1983
    Date of Patent: May 14, 1985
    Assignee: The Eastern Company
    Inventors: David B. MacPherson, Jay E. Paris, Robert W. Foley, Martin W. Greinier, David N. Pulsifer