Patents by Inventor William H. McMahan

William H. McMahan 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: 5681307
    Abstract: The present invention provides a system for communicating information from a detachable appliance to a base unit so that the base unit can calibrate its operation to match the characteristics of the detachable appliance. The invention has particular benefits when used with medical lasers. A receptacle, mounted on the laser base unit, is provided for operatively receiving a plug on the appliance and transferring energy from the base unit to the detachable appliance. To convey information about the appliance from the appliance to the base unit, an information bearing surface is mounted on the plug and is oriented substantially perpendicularly to the external surface of the plug. The information bearing surface includes a plurality of information zones which are each machine readable and optically readable by the base unit. The base unit includes components for optically detecting and decoding the information embedded in the information zones when the plug is received by the receptacle.
    Type: Grant
    Filed: October 26, 1994
    Date of Patent: October 28, 1997
    Inventor: William H. McMahan
  • Patent number: 5498935
    Abstract: An apparatus and method for controlling the current delivered to a flash lamp is disclosed. The apparatus and method is particularly useful for controlling the current delivered to a flash lamp used in a laser and most particularly useful in connection with lasers used for medical procedures. The apparatus controls the length of the electrical pulse which is delivered to the flash lamp and also limits the current which passes through the flash lamp to that which is desired for optimized operation. A semiconductor switch electrically connects and disconnects the flash lamp from one or more capacitors for the desired length of time. The length of time can be automatically adjusted to provide the desired flash lamp output and thus the desired laser output. The switch provides substantially a square wave having a plateau voltage with very fast rise and fall times on both sides of the plateau so that a suitable square wave is formed.
    Type: Grant
    Filed: November 12, 1993
    Date of Patent: March 12, 1996
    Assignee: William H. McMahan
    Inventors: William H. McMahan, Kevin W. Gordon
  • Patent number: 5413555
    Abstract: A laser delivery system which may be coupled to a stereomicroscope or camera equivalent, may be three dimensionally positioned such that a laser beam may irradiate a wide range of treatment sites from a variety of angles and distances, and where the laser beam may be positioned at an angle to the viewing axis and track along therewith. A laser delivery system including a filter/mirror system which allows only proper wavelengths to be transmitted.
    Type: Grant
    Filed: April 30, 1993
    Date of Patent: May 9, 1995
    Inventor: William H. McMahan
  • Patent number: 4951296
    Abstract: The anode end of a gas laser is constructed so as to include an electrically and thermally insulating barrier between the Brewster window and the anode end of the tube bore thereby permitting cooler operating temperatures at the Brewster window and confinement of the electric discharge within the anode itself.
    Type: Grant
    Filed: July 10, 1989
    Date of Patent: August 21, 1990
    Assignee: McMahan Laser Corporation
    Inventor: William H. McMahan
  • Patent number: 4504951
    Abstract: A high speed switching power supply for a laser system is disclosed. In the preferred embodiment, proportional-plus-derivative feedback of the emitted light controls the duty cycle of the MOS-FET switching transistor to vary the d.c. voltage level applied across a storage capacitor from a d.c. power supply. The storage capacitor is connected across a laser tube to apply its stored voltage thereto. The MOS-FET transistor permits high speed switching. The derivative portion of the feedback damps out oscillatory tendencies in the feedback loop to permit increased loop bandwidth. The combination of the MOS-FET transistor and proportional-plus-derivative feedback permits the laser output to be controlled in a voltage-controlled mode.
    Type: Grant
    Filed: June 1, 1982
    Date of Patent: March 12, 1985
    Assignee: American Laser Corporation
    Inventors: William H. McMahan, Steve H. Holtman
  • Patent number: 4481633
    Abstract: A segmented ceramic tube for an argon-ion laser is fluid cooled and constructed to avoid shunting of current through the coolant.
    Type: Grant
    Filed: January 15, 1982
    Date of Patent: November 6, 1984
    Assignee: Laser Corporation
    Inventor: William H. McMahan
  • Patent number: 4477907
    Abstract: An argon-ion laser achieves low output power by using a plasma guide and mirror configuration which restricts lasing action to a portion of the resonator cavity at relatively high conversion efficiency.
    Type: Grant
    Filed: May 3, 1982
    Date of Patent: October 16, 1984
    Assignee: American Laser Corporation
    Inventor: William H. McMahan
  • Patent number: 4430739
    Abstract: A laser system having an intermediate mode of laser beam operation wherein the laser beam is extinguished but the laser cathode continues to remain energized. The laser system includes an electronic circuit in which energy is stored while the laser beam is extinguished so that the laser beam can be substantially instantaneously re-ignited when the stored energy is released to the laser anode.
    Type: Grant
    Filed: September 21, 1981
    Date of Patent: February 7, 1984
    Inventor: William H. McMahan
  • Patent number: 4385390
    Abstract: An improved bypass inhibitor attached to but not constituting part of the laser bore assembly of a ceramic gas laser tube having main and gas bypass bores comprises a ceramic disc, one side of which is both metal bonded to the tube and formed with metal surface channels to reduce bypass gas ignition without significantly inhibiting bypass gas passage therethrough.
    Type: Grant
    Filed: February 9, 1981
    Date of Patent: May 24, 1983
    Assignee: American Laser Corporation
    Inventor: William H. McMahan
  • Patent number: 4380077
    Abstract: A laser tube made of electrically insulating ceramic material, e.g., BeO, is formed of dry pressed and fired segments brazed together and with a chamfer or stepped area at the end of each segment adapted to interrupt the bore so as to prevent the establishment of a continuous electrically conducting layer in the tube bore.
    Type: Grant
    Filed: February 9, 1981
    Date of Patent: April 12, 1983
    Assignee: American Laser Corporation
    Inventor: William H. McMahan
  • Patent number: 4229709
    Abstract: A means is provided for continuously purging deleterious contaminants including water vapor, ozone and organic vapors from the resonant cavity of lasers where the resonant cavity is characterized by a gap-space between the gain medium and the optical mirror at both ends of the cavity with each of the gap-spaces being disposed within an enclosed chamber where the contaminants tend to collect. This is accomplished by connecting the interiors of the gap-space chambers through tubular gas conduits with one or more canisters which contain a chemical desiccant or molecular sieve capable of removing the unwanted gases or vapors. A molecular sieve comprised of zeolite with the appropriate intermolecular spacing is especially preferred.
    Type: Grant
    Filed: June 12, 1978
    Date of Patent: October 21, 1980
    Inventor: William H. McMahan
  • Patent number: D381325
    Type: Grant
    Filed: October 27, 1995
    Date of Patent: July 22, 1997
    Assignee: William H. McMahan
    Inventors: William H. McMahan, Jeffrey A. Reed