Patents by Inventor Duncan L. MacFarlane

Duncan L. MacFarlane 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: 7711271
    Abstract: The invention provides for optical circulators which redirect light from port to port sequentially in one direction used to separate traffic in a bidirectional optical fiber transmission system. The invention provides for using two optical circulators in each span of bidirectional fiber so that the OSC channel can be transmitted in one direction opposite to the WDM channels. The invention also provides for a gigabit Ethernet path between chassis which is utilized for control traffic and customer traffic. The invention is placed in a non-critical region of the optical spectrum and is independent of all other chassis equipment. The invention also provides the advantage in alternate embodiments of providing the option of a second counter propagating WDM channel being transmitted along with the OSC to provide additional system capacity. The invention also provides the advantage in an alternate embodiment of allowing the OSC to be amplified through a raman source without the need of complete system retrofit.
    Type: Grant
    Filed: April 30, 2003
    Date of Patent: May 4, 2010
    Inventors: Michael H. Eiselt, Lara Garrett, Duncan L. MacFarlane, Jeffrey Lloyd Cox
  • Patent number: 7498811
    Abstract: The present invention relates, in general, to the field of motion tracking, and in particular to join a target in an MRI application. In particular the invention teaches an apparatus and method to track the movement of a target during medical imaging scanning using optical technology. Optical systems record the position and movement of the pattern and are able to perform mathematical analysis of the pattern to determine the positional shift of the patient. Weighted averages, Fourier transforms, Hadamard matrices and cross-correlation of data related to X-Y translation, rotation and scaling of the image of the pattern are used to analyze movement of the subject's head. Feedback related to the movement is provided to the MRI machine which allows for adjustments in focusing coils for real time tracking of the patient's movements during the MRI procedure. As a result, the MRI procedure becomes more accurate as it is adjusted for the patient's movements.
    Type: Grant
    Filed: November 16, 2005
    Date of Patent: March 3, 2009
    Inventors: Duncan L. MacFarlane, Richard Briggs, Andrei A. Zaremba, Keith D. White
  • Publication number: 20090039235
    Abstract: The present invention discloses a method for determining location and movement of a moving object. One embodiment of the method tracks the movement of a target during medical imaging scanning and transmits the position shift to the medical imaging scanning device in real time. The method includes the steps of projecting structured light on the target, receiving the reflection of structured light, converting the received structured light into spatial positions, and transmitting the positional shift to the medical imaging scanning device. The method further includes the step of adjusting the medical imaging scanning device in response to the positional change to increase accuracy.
    Type: Application
    Filed: May 19, 2008
    Publication date: February 12, 2009
    Inventors: Duncan L. MacFarlane, Richard Briggs, Andrei A. Zaremba, Keith D. White
  • Patent number: 7215462
    Abstract: A multi-section filter is provided for use in processing optical signals and other signals that can be readily projected from one filter section to another. Filters of the invention can be configured in numerous forms, including IIR and FIR filters and both linear and 2D active optical lattice filters. Filter sections are coupled together by means of four direction couplers and surface grating couplers, and may be implemented as GSE photonic integrated circuit devices.
    Type: Grant
    Filed: March 16, 2006
    Date of Patent: May 8, 2007
    Assignee: Board of Regents, The University of Texas System
    Inventor: Duncan L. MacFarlane
  • Patent number: 7042657
    Abstract: A multi-section filter is provided for use in processing optical signals and other signals that can be readily projected from one filter section to another. Filters of the invention can be configured in numerous forms, including IIR and FIR filters and both linear and 2D active optical lattice filters. Filter sections are coupled together by means of four direction couplers and surface grating couplers, and may be implemented as GSE photonic integrated circuit devices.
    Type: Grant
    Filed: August 28, 2003
    Date of Patent: May 9, 2006
    Assignee: Board of Regents The University of Texas System
    Inventor: Duncan L. MacFarlane
  • Publication number: 20040033080
    Abstract: The invention provides for optical circulators which redirect light from port to port sequentially in one direction used to separate traffic in a bidirectional optical fiber transmission system. The invention provides for using two optical circulators in each span of bidirectional fiber so that the OSC channel can be transmitted in one direction opposite to the WDM channels.
    Type: Application
    Filed: April 30, 2003
    Publication date: February 19, 2004
    Inventors: Michael H. Eiselt, Lara Garrett, Duncan L. MacFarlane, Jeffrey Lloyd Cox
  • Patent number: 6687461
    Abstract: The present invention is an optical signal processing apparatus which centers around an active optical filter. The active optical lattice filter permits ultra-high bandwidth signal processing of optical signals. The filter utilizes a lattice arrangement of optical amplifiers and interfaces which feed and reinforce each other. The lattice sections are constructed of a semiconductive material so that the device may be used as an optoelectronic component of an optical communications system. A control voltage is applied to each optical amplifier thereby enabling a user to electronically control and tune the optical transfer function of the device. The lattice parameters may be adjusted to produce an tunable oscillation to produce a precision optical line frequency. Precision optical line frequencies are useful in dense wavelength division multiplexers. Also, the lattice parameters may be adjusted to produce very high-Q optical filters are needed to construct dense wavelength division demultiplexers.
    Type: Grant
    Filed: November 2, 1999
    Date of Patent: February 3, 2004
    Assignee: Board of Regents, The University of Texas System
    Inventors: Duncan L. MacFarlane, Eric M. Dowling
  • Patent number: 6407650
    Abstract: A system (200) for transmitting and focusing surface acoustic waves (208) along a substrate (206) is disclosed. The system (200) comprising a curved transmission element (202) that is disposed upon the substrate (206). The curved transmission element (202) is adapted to propagate an acoustic wave (212). The system (200) also comprises a curved receiving element (206) that is disposed upon the substrate in relation to the curved transmission element (202). The curved receiving element (206) is adapted to receive the acoustic wave (212) and match the acoustic wave's size and shape.
    Type: Grant
    Filed: August 27, 1999
    Date of Patent: June 18, 2002
    Assignee: Board of Regents The University of Texas System
    Inventor: Duncan L. MacFarlane
  • Patent number: 5801666
    Abstract: A three-dimensional computer monitor is provided for displaying information and representations of objects in three dimensions. In a preferred embodiment, the monitor comprises a three dimensional array of optical voxels that are individually activated by energy transmitted through optical fibers coupled to each voxel. The energy, such as visible or ultraviolet light, may be conducted into selected optical fibers using a two dimensional shutter array or a plurality of controllable energy sources, under the direction of a digital computer. The voxels may be made of polymethylmethacrylate doped with a dye that fluoresces when energy, such as ultraviolet light, is introduced into a voxel. A color monitor may be constructed by selecting a plurality of dyes to produce voxels that emit different colors. The intensity of each of, for example, adjacent red, green and blue voxels can be controlled to produce a variety of colors.
    Type: Grant
    Filed: February 10, 1993
    Date of Patent: September 1, 1998
    Assignee: Board of Regents, The University of Texas System
    Inventor: Duncan L. MacFarlane
  • Patent number: 5307210
    Abstract: We describe a device for aligning optical beams that uses either an elliptically curved or a parabolically curved mirror arranged in the reflected beam path between a rotatable mirror, which is placed at the focus of the curved mirror, and the desired target. With the elliptical mirror, the device provides variable angle, fixed position of incidence of the reflected beam upon a target placed at the second focus of the ellipse. With the parabolic mirror, the device provides variable position, fixed angle of incidence of the reflected beam upon a target. Combinations of these devices may be used to solve a variety of beam steering and/or beam alignment problems. These devices are particularly useful for experiments and applications involving ultrashort optical pulses since the time of flight through either of these devices is a constant independent of the angle of incidence and the position of incidence.
    Type: Grant
    Filed: May 3, 1990
    Date of Patent: April 26, 1994
    Assignee: Board of Regents, The University of Texas System
    Inventors: Duncan L. MacFarlane, Dale M. Byrne