Patents Assigned to SFA, Inc.
  • Patent number: 5058980
    Abstract: Light energy is efficiently coupled into a laser rod in a direction parallel to a resonating mode of the rod through optical fibers. Individual optical fibers having a refractive index lower than the refractive index of the laser rod are placed side by side around a barrel portion of a laser rod, parallel to the direction of the resonating mode, with the core portions of the optical fibers exposed by stripping the cladding. Since the law of total internal reflection for the light in the fibers is violated when the light encounters the higher refractive index of the laser rod, the exposed cores contacting the laser rod couple light energy injected into ends of the fibers to the laser rod. A reflector at end of the fibers opposite the light injection allows uncoupled light energy to be coupled into the laser rod on a second pass.
    Type: Grant
    Filed: February 21, 1990
    Date of Patent: October 22, 1991
    Assignee: SFA, Inc.
    Inventor: Phillip H. Howerton
  • Patent number: 5057287
    Abstract: A method and apparatus for growing an extended length single crystal of a Group III-V or II-VI material such as GaAs by moving a crucible containing a seed crystal and precompounded crystal material encapsulated in a molten encapsulant preferably vertically in a multi-zone furnace between two furnace zones maintained at temperatures above the melting point of the encapsulant but below the melting point of the crystal material through an intervening short "spike" zone maintained at a temperature at least equal to the melting temperature of the crystal material to crystallize the precompounded crystal material with the seed crystal, and tipping the crucible in the furnace, e.g. by tipping the furnace with the crucible in it, to decant the encapsulant prior to recovering the crystal.
    Type: Grant
    Filed: August 8, 1990
    Date of Patent: October 15, 1991
    Assignee: SFA, Inc.
    Inventor: Edward M. Swiggard
  • Patent number: 5007980
    Abstract: A method and apparatus for growing an extended length single crystal of a Group III-V or II-VI material such as GaAs by moving a crucible containing a seed crystal and precompounded crystal material encapsulated in a molten encapsulant preferably vertically in a multi-zone furnace between two furnace zones maintained at temperatures above the melting point of the encapsulant but below the melting point of the crystal material through an intervening short "spike" zone maintained at a temperature at least equal to the melting temperature of the crystal material to crystallize the precompounded crystal material with the seed crystal, and tipping the crucible in the furnace, e.g. by tipping the furnace with the crucible in it, to decant the encapsulant prior to recovering the crystal.
    Type: Grant
    Filed: November 1, 1988
    Date of Patent: April 16, 1991
    Assignee: SFA, Inc.
    Inventor: Edward M. Swiggard
  • Patent number: D368474
    Type: Grant
    Filed: July 27, 1994
    Date of Patent: April 2, 1996
    Assignee: SFA, Inc.
    Inventor: Philip D. Wise