Patents by Inventor Robert S. Harp

Robert S. Harp 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: 5524479
    Abstract: A scanning probe microscope is provided with a piezo-ceramic tube to carry the sensitive probe at its free end to translationally move the probe in the X and Y directions. Large stationary surfaces can then be scanned by probe tip motion. The tube is also capable of movement in the Z direction so that the tip can follow the contours of the surface. Optical detection means track the motion of the probe tip and generate signals corresponding to and representative of surface contours. In one mode of operation, the signals are used in a feed back loop to keep constant the spacing between the tip and the surface, in which case the error or control signals represent the contours.
    Type: Grant
    Filed: January 24, 1995
    Date of Patent: June 11, 1996
    Assignee: Ouesant Instrument Corporation
    Inventors: Robert S. Harp, David J. Ray
  • Patent number: 5466935
    Abstract: Scanned-probe microscope systems (20, 140) are disclosed with analog control loops (24, 144) that can be electronically programmed to select from a plurality of transfer functions. The amplitude of the control loop reference signal (64) can also be electronically programmed. A controller (26) enables an operator to quickly program these operational characteristics. The controller preferably includes a visual display (33) and a recording device (32) to facilitate the programming and to display and store the scanning data obtained with the selected characteristics.
    Type: Grant
    Filed: January 20, 1995
    Date of Patent: November 14, 1995
    Assignee: Quesant Instrument Corporation
    Inventors: David J. Ray, Robert S. Harp
  • Patent number: 5388452
    Abstract: A scanning probe microscope is provided with a piezo-ceramic tube to carry the sensitive probe at its free end to translationally move the probe in the X and Y directions. Large stationary surfaces can then be scanned by probe tip motion. The tube is also capable of movement in the Z direction so that the tip can follow the contours of the surface. Optical detection means track the motion of the probe tip and generate signals corresponding to and representative of surface contours. In one mode of operation, the signals are used in a feed back loop to keep constant the spacing between the tip and the surface, in which case the error or control signals represent the contours.
    Type: Grant
    Filed: October 15, 1993
    Date of Patent: February 14, 1995
    Assignee: Quesant Instrument Corporation
    Inventors: Robert S. Harp, David J. Ray
  • Patent number: 5357105
    Abstract: A scanning force microscope is provided with apparatus to modify the light source with a modulation scheme. Information relative to scanning tip motion is included in a modulated light beam which is then demodulated and filtered to recover the information in the form of a signal which corresponds to and is representative of a chosen parameter of tip motion.
    Type: Grant
    Filed: November 9, 1993
    Date of Patent: October 18, 1994
    Assignee: Quesant Instrument Corporation
    Inventors: Robert S. Harp, David J. Ray
  • Patent number: 4238747
    Abstract: A mode filter apparatus for preventing unwanted modes in a multi-moded structure utilizing a radial plurality of resonant slots on the bottom of the filter cavity. The top of the filter cavity includes a variable height center section to provide mode selectivity in cooperation with the resonant slots.
    Type: Grant
    Filed: August 10, 1979
    Date of Patent: December 9, 1980
    Assignee: The United States of America as represented by the Secretary of the Air Force
    Inventors: Robert S. Harp, Kenneth J. Russell
  • Patent number: 4188590
    Abstract: The specification describes a solid state microwave power combiner wherein a plurality of solid state power generating devices are mounted between adjacent conical support and housing structures. These structures define the microwave electrical circuits for these devices, and also as provide a waveguiding region for propagating energy from these devices to a common output line. Both the support and housing structures have their apexes integrally joined, respectively, to input and output conductors of a common output coaxial line used for coupling power out of the combiner. This novel geometrical configuration minimizes the electrical distance between the power generating devices and the coaxial output line, maximizes the packing density of the structure and optimizes the electrical performance of RF termination elements for these devices.
    Type: Grant
    Filed: November 25, 1977
    Date of Patent: February 12, 1980
    Assignee: Hughes Aircraft Company
    Inventors: Robert S. Harp, Kenneth J. Russell
  • Patent number: 4032865
    Abstract: Disclosed is an active radial-to-coaxial transmission line wherein an annular configured semiconductor device, such as an IMPATT diode, is embedded in a chosen dielectric material which is in turn positioned between two conductive members forming a radial transmission line. Advantageously, the lower conductive member of the transmission line also serves as a heat sink for the diode, and the upper conductive member of the radial transmission line may be formed as a highly conductive coating which makes good ohmic contact to the diode, thereby minimizing power losses at this contact. The radial transmission line transforms the relatively low impedance of the diode to a substantially higher value at the outer periphery thereof where contact to a coaxial transmission line may be achieved with good impedance matching, thereby maximizing power transfer between the radial and coaxial transmission lines.
    Type: Grant
    Filed: March 5, 1976
    Date of Patent: June 28, 1977
    Assignee: Hughes Aircraft Company
    Inventors: Robert S. Harp, Kenneth J. Russell
  • Patent number: 3942130
    Abstract: A transmission line transition for coupling together a coaxial transmission line and a parallel plane radial transmission line, the transition including upper and lower circular plates having conforming inner curved surfaces spaced from each other to define an air dielectric transmission line comprising, in succession, a coaxial air line section, a transition air line section, and a radial air line section.
    Type: Grant
    Filed: December 30, 1974
    Date of Patent: March 2, 1976
    Assignee: Hughes Aircraft Company
    Inventor: Robert S. Harp
  • Patent number: 3931587
    Abstract: Disclosed is a microwave power accumulator including a plurality of coaxial oscillator circuits, each tightly coupled to a single common output combining resonant cavity. Each of the coaxial circuits includes a negative resistance diode at one end and a lossy terminating (microwave absorbing) material at the other end which absorbs and suppresses resonant modes within each coaxial circuit. This feature enables the cavity resonance of the common output combining cavity to dominate all of the individual coaxial circuits spaced therearound. The spacing of these coaxial circuit modules around a common cylindrical output combining cavity permits a high packing density and good individual heat sinking for the accumulator.
    Type: Grant
    Filed: February 3, 1975
    Date of Patent: January 6, 1976
    Assignee: Hughes Aircraft Company
    Inventors: Robert S. Harp, Harry L. Stover
  • Patent number: RE37404
    Abstract: A scanning probe microscope is provided with a piezo-ceramic tube to carry the sensitive probe at its free end to translationally move the probe in the X and Y directions. Large stationary surfaces can then be scanned by probe tip motion. The tube is also capable of movement in the Z direction so that the tip can follow the contours of the surface. Optical detection means track the motion of the probe tip and generate signals corresponding to and representative of surface contours. In one mode of operation, the signals are used in a feed back loop to keep constant the spacing between the tip and the surface, in which case the error or control signals represent the contours.
    Type: Grant
    Filed: February 14, 1997
    Date of Patent: October 9, 2001
    Assignee: Quesant Instrument Corporation
    Inventors: Robert S. Harp, David J. Ray