Patents by Inventor Afshin S. Daryoush

Afshin S. Daryoush 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: 9823113
    Abstract: Disclosed is detecting changes in pressure in a medium, with an optical fiber having a core diameter at an immersion surface contact of the fiber of less than 10 ?m; a layer of material deposited on said end of the fiber, the material being of a thickness of from about 2 nm to about 10 nm. Also disclosed is detecting pressure waves in a medium comprising: contacting the medium with a fiber optic, the fiber integrated with a light source and a detector, the fiber optic having a diameter of less than 10 ?m at an immersion surface contact of the fiber; providing a thin layer of material on the immersion surface contact, wherein said thin layer of material is of a thickness in a range of from about 2 nm to about 10 nm; and detecting Fresnel back reflections from the immersion end of the fiber.
    Type: Grant
    Filed: January 21, 2014
    Date of Patent: November 21, 2017
    Assignee: Drexel University
    Inventors: Afshin S Daryoush, Peter A Lewin, Rupa Gopinath Minasamudram, Mahmoud El-Sherif
  • Publication number: 20170199076
    Abstract: A sensing method is based on using a special fiberoptic probe for detection of acoustic/ultrasound pressure in an immersion medium. The developed system is highly sensitive in detecting ultrasound waves up to 100 MHz, for imaging of micro structures and more. For applications up to 100 MHz, without spatial averaging corrections, the probe tip is modified by reducing the fiber diameter to 7 um or less. Also, to maximize acousto-optic interaction, the probe tip, not just its end face, may be coated with a thin layer of metallic material. This thin film coating satisfies partial transparency of the metallic coating. The coating thickness may range from 2 nm to 10 nm or others depending on the type of the coating material. The probe detects the pressure of acoustic and/or ultrasound waves propagating within an immersion medium, whenever the probe tip is immersed inside the medium, and having a reasonable immersion contact surface.
    Type: Application
    Filed: April 3, 2017
    Publication date: July 13, 2017
    Applicant: Drexel University
    Inventors: Mahmoud A. El-Sherif, Afshin S. Daryoush, Peter A. Lewin, Rupa Gopinath Minasamudram
  • Patent number: 9094133
    Abstract: The present invention details fabrication guidelines of integrated optoelectronic oscillators with frequency and phase stability, having higher frequency selectivity in a relatively small size (compared to the larger size of a higher order electrically realized RF filter), reduced temperature sensitivity, and minimized frequency drift. The integrated photonic components and RF oscillator may use Silicon photonics and microelectronic integration using CMOS and BiCMOS technology, eliminating the need for bulky and/or discrete optical and microwave components.
    Type: Grant
    Filed: March 12, 2013
    Date of Patent: July 28, 2015
    Assignee: Synergy Microwave Corporation
    Inventors: Ajay Kumar Poddar, Ulrich L. Rohde, Afshin S. Daryoush
  • Patent number: 9088369
    Abstract: Aspects of the disclosure relate generally to a circuit for sustaining an radio frequency (RF) modulated optical signal. The circuit may comprise a self injection locking component having a fiber optic delay line over which a portion of the optical signal propagates. The circuit may also comprise a self phase locked loop component having at least two fiber optic cables having different lengths and over which another portion of the optical signal propagates and a phase detector coupled to the at least two fiber optic cables and configured to determine a phase difference between the signals propagating over one of the respective fiber optic cables. The circuit may further comprise a voltage controlled oscillator configured to generate a stable oscillating signal in response to signals generated by each of the self injection locking and self phase locked loop components, the stable oscillating signal being configured to sustain the optical signal.
    Type: Grant
    Filed: February 6, 2013
    Date of Patent: July 21, 2015
    Assignee: Synergy Microwave Corporation
    Inventors: Ajay Kumar Poddar, Ulrich L. Rohde, Afshin S. Daryoush
  • Publication number: 20140133280
    Abstract: Disclosed is detecting changes in pressure in a medium, with an optical fiber having a core diameter at an immersion surface contact of the fiber of less than 10 ?m; a layer of material deposited on said end of the fiber, the material being of a thickness of from about 2 nm to about 10 nm. Also disclosed is detecting pressure waves in a medium comprising: contacting the medium with a fiber optic, the fiber integrated with a light source and a detector, the fiber optic having a diameter of less than 10 ?m at an immersion surface contact of the fiber; providing a thin layer of material on the immersion surface contact, wherein said thin layer of material is of a thickness in a range of from about 2 nm to about 10 nm; and detecting Fresnel back reflections from the immersion end of the fiber.
    Type: Application
    Filed: January 21, 2014
    Publication date: May 15, 2014
    Inventors: Afshin S. Daryoush, Peter A. Lewin, Rupa Gopinath Minasamudram, Mahmoud El-Sherif
  • Patent number: 8661908
    Abstract: Disclosed is detecting changes in pressure in a medium, with an optical fiber having a core diameter at an immersion surface contact of the fiber of less than 10 ?m; a layer of material deposited on said end of the fiber, the material being of a thickness of from about 2 nm to about 10 nm. Also disclosed is detecting pressure waves in a medium comprising: contacting the medium with a fiber optic, the fiber integrated with a light source and a detector, the fiber optic having a diameter of less than 10 ?m at an immersion surface contact of the fiber; providing a thin layer of material on the immersion surface contact, wherein said thin layer of material is of a thickness in a range of from about 2 nm to about 10 nm; and detecting Fresnel back reflections from the immersion end of the fiber.
    Type: Grant
    Filed: June 1, 2011
    Date of Patent: March 4, 2014
    Assignee: Drexel University
    Inventors: Afshin S. Daryoush, Peter A. Lewin, Rupa Gopinath Minasamudram, Mahmoud A. El-Sherif
  • Publication number: 20110305118
    Abstract: Disclosed is detecting changes in pressure in a medium, with an optical fiber having a core diameter at an immersion surface contact of the fiber of less than 10 ?m; a layer of material deposited on said end of the fiber, the material being of a thickness of from about 2 nm to about 10 nm. Also disclosed is detecting pressure waves in a medium comprising: contacting the medium with a fiber optic, the fiber integrated with a light source and a detector, the fiber optic having a diameter of less than 10 ?m at an immersion surface contact of the fiber; providing a thin layer of material on the immersion surface contact, wherein said thin layer of material is of a thickness in a range of from about 2 nm to about 10 nm; and detecting Fresnel back reflections from the immersion end of the fiber.
    Type: Application
    Filed: June 1, 2011
    Publication date: December 15, 2011
    Applicant: DREXEL UNIVERSITY
    Inventors: Afshin S. Daryoush, Peter A. Lewin, Rupa Gopinath Minasamudram, Mahmoud A. El-Sherif
  • Patent number: 5465418
    Abstract: Self-oscillating mixer circuits for use in communications systems. The circuits comprise a push-pull amplifier for amplifying a signal having a first frequency to produce an amplified signal, a feedback loop coupled to the push-pull amplifier for phase shifting the amplified signal during each half cycle of the push-pull amplifier, thereby creating an oscillating output signal, and a mixing element for coupling the oscillating output signal to the signal having the first frequency, thereby mixing the signal having the first frequency with the oscillating signal to produce a signal having a second frequency. The circuits described herein have transistors that operate near the class B mode to obtain optimal frequency conversion with minimal power consumption. These circuits will therefore find use in any communications-type system which requires a frequency converter.
    Type: Grant
    Filed: January 13, 1994
    Date of Patent: November 7, 1995
    Assignee: Drexel University
    Inventors: Xuesong Zhou, Afshin S. Daryoush
  • Patent number: 5302918
    Abstract: A fundamental or subharmonic optically injection locked oscillator is coupled to a phase locked loop circuit. The injection locked oscillator has two single stage HEMT amplifiers with parallel feedback from the drain of a second transistor to a gate of a first transistor. A feedback resonant network controls the oscillator frequency. A microwave/millimeter wave source modulates a laser diode and the signal from the laser diode is then transmitted via an optical fiber to a PIN photodetector diode. The signal from the photodetector diode is injected into the oscillator at an nth subharmonic of the oscillator frequency. The feedback network may consist of a microstrip gap resonator with two tuning varactors at the ends of the resonator. The phase locked loop includes a balanced mixer used as a phase detector to compare the nth harmonic of the signal from the photodetector diode to the sampled output of the oscillator.
    Type: Grant
    Filed: June 1, 1993
    Date of Patent: April 12, 1994
    Assignee: The United States of America as represented by the Secretary of the Army
    Inventors: Dana J. Sturzebecher, Thomas P. Higgins, Afshin S. Daryoush
  • Patent number: 5214525
    Abstract: An optical transmitter particularly suited for high frequency applications s disclosed. The optical transmitter successfully operates in harsh environments such as those found in avionic applications. The optical transmitter employs an LED as a light source which cooperates with an active bandpass amplifier to provide a relatively wide bandwidth from about 250 MHz to about at least 1.35 GHz. The bandpass amplifier is selected to have a slope characteristic which is complementary to a roll-off characteristic of the LED and compensates for the high frequency loss of the LED. The slope characteristic of the bandpass amplifier predominates at the high frequencies of the response of the optical transmitter, whereas the frequency response of the LED dominates at the lower frequencies of the response.
    Type: Grant
    Filed: September 13, 1991
    Date of Patent: May 25, 1993
    Assignee: The United States of America as represented by the Secretary of the Navy
    Inventors: Vladimir Gershman, Afshin S. Daryoush, Warren A. Rosen
  • Patent number: 4751513
    Abstract: The characteristics of antennas are modified by photosensitive electrical elements connected to the radiating elements. The photosensitive elements are biased by light, by direct electrical bias, or both. The photosensitive element may be a PIN diode. The bias may be applied by general illumination or conducted by a fiber optic cable.
    Type: Grant
    Filed: May 2, 1986
    Date of Patent: June 14, 1988
    Assignee: RCA Corporation
    Inventors: Afshin S. Daryoush, Peter R. Herczfeld, Arye Rosen