Patents by Inventor Nicholas Djeu

Nicholas Djeu 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: 11311336
    Abstract: A hand piece for delivering energy from a laser to a target through a fiber tip includes an elongated handle having a proximal end and a distal end. An axial bore traverses the handle along a longitudinal axis thereof. A fiber tip holding mechanism is fixed within the axial bore of the handle and includes a forward section fixed with the handle, a spring, and a rear section that includes a hollow collet projecting forward therefrom that traverses the spring and the forward section. The forward section is slidable rearward towards the rear section to compress the spring in a rear position. The spring urges the forward section forward into a forward position. A chuck is fixed with the forward end of the fiber tip holding mechanism and includes a tapered sleeve and two or more oppositely tapered jaws.
    Type: Grant
    Filed: February 22, 2021
    Date of Patent: April 26, 2022
    Inventors: Derek Djeu, Nicholas Djeu
  • Patent number: 10392721
    Abstract: A laser heated pedestal growth system includes two lasers having output beams that are combined with a beam combiner to produce a single beam. A growth chamber that includes a final focusing mirror for receiving and focusing the single beam of the lasers onto a tip of a feed material to create a molten zone in a focal region. A feed transport mechanism is adapted for transporting a feed material through the growth chamber and into the molten zone. An opposing seed transport mechanism is adapted for withdrawing a seed material from the growth chamber. An imaging system is adapted for capturing an image of the molten zone within the growth chamber. A controller in communication with the feed transport mechanism, the seed transport mechanism, one of the two lasers, and the imagining system is adapted to control and stabilize a fiber growth process by controlling the feed transport mechanism, the seed transport mechanism, and the power of the combined laser beam.
    Type: Grant
    Filed: July 16, 2018
    Date of Patent: August 27, 2019
    Inventor: Nicholas Djeu
  • Patent number: 9134177
    Abstract: In accordance with the present invention, a novel self-referencing fiber optic Raman probe is disclosed. It uses the Raman signal generated by a crystalline optical fiber to normalize the Raman signal produced by the sample in order to compensate for changes in the output power of the excitation laser light source, the coupling efficiencies of the optical fibers connecting the light source to the probe and the probe to the analyzing spectrometer, and the alignment of optical components within the probe.
    Type: Grant
    Filed: March 13, 2013
    Date of Patent: September 15, 2015
    Inventor: Nicholas Djeu
  • Publication number: 20140268129
    Abstract: In accordance with the present invention, a novel self-referencing fiber optic Raman probe is disclosed. It uses the Raman signal generated by a crystalline optical fiber to normalize the Raman signal produced by the sample in order to compensate for changes in the output power of the excitation laser light source, the coupling efficiencies of the optical fibers connecting the light source to the probe and the probe to the analyzing spectrometer, and the alignment of optical components within the probe.
    Type: Application
    Filed: March 13, 2013
    Publication date: September 18, 2014
    Inventor: Nicholas Djeu
  • Patent number: 8736835
    Abstract: In accordance with the present invention, a dual-gas Raman sensor is provided that is based on an enhanced spontaneous dual emission as a result of cavity quantum electrodynamic effects. The dual-gas sensor includes a first reflector that exhibits a high reflectivity near the Raman shifted emission for the first species of interest and a moderate reflectivity near the Raman shifted emission for the second species of interest and a second reflector that exhibits a high reflectivity near the Raman shifted emission for the first species of interest and a moderate reflectivity near the Raman shifted emission for the second species of interest, allowing for the simultaneous measurement of the density of both the first species of interest and the second species of interest.
    Type: Grant
    Filed: November 14, 2013
    Date of Patent: May 27, 2014
    Assignee: University of South Florida
    Inventors: Nicholas Djeu, Andreas Muller
  • Publication number: 20140071446
    Abstract: In accordance with the present invention, a dual-gas Raman sensor is provided that is based on an enhanced spontaneous dual emission as a result of cavity quantum electrodynamic effects. The dual-gas sensor includes a first reflector that exhibits a high reflectivity near the Raman shifted emission for the first species of interest and a moderate reflectivity near the Raman shifted emission for the second species of interest and a second reflector that exhibits a high reflectivity near the Raman shifted emission for the first species of interest and a moderate reflectivity near the Raman shifted emission for the second species of interest, allowing for the simultaneous measurement of the density of both the first species of interest and the second species of interest.
    Type: Application
    Filed: November 14, 2013
    Publication date: March 13, 2014
    Applicant: UNIVERSITY OF SOUTH FLORIDA
    Inventors: Nicholas Djeu, Andreas Muller
  • Patent number: 8599373
    Abstract: In accordance with the present invention, an ultra-sensitive Raman chemical sensor is provided that is based on an enhanced spontaneous emission as a result of cavity quantum electrodynamic effects. More specifically, the sensor in accordance with the present invention makes use of a double resonance of a microcavity with both the excitation laser frequency and the Raman frequency. As such, the Raman shift corresponds to an integer times the free spectral range of the microcavity. Because the Raman frequency directly depends on the excitation laser's frequency, the fulfillment of the resonance condition for the excitation laser frequency guarantees that resonance with the Raman frequency is also satisfied.
    Type: Grant
    Filed: July 5, 2012
    Date of Patent: December 3, 2013
    Assignee: University of South Florida
    Inventors: Nicholas Djeu, Andreas Muller
  • Patent number: 8592768
    Abstract: A fiber optic evanescent absorption sensor. This invention makes use of two sources and one detection system, or one source and two detection systems, or two of each to determine a large range of absorbance with high accuracy for a fixed interaction length.
    Type: Grant
    Filed: April 6, 2010
    Date of Patent: November 26, 2013
    Assignee: University of South Florida
    Inventor: Nicholas Djeu
  • Patent number: 8011827
    Abstract: The present invention provides a dual-probe thermally compensated fluorescence decay rate temperature sensor capable of measuring the true temperature of a sample surface and its associated method of use.
    Type: Grant
    Filed: September 3, 2010
    Date of Patent: September 6, 2011
    Assignee: University of South Florida
    Inventor: Nicholas Djeu
  • Patent number: 7855780
    Abstract: Disclosed is a spectroscopic system having a fiber-optic probe for simultaneous IR and Raman measurement. The probe includes a single strand of optical fiber, such as sapphire which is suitable for IR absorption measurements as far as 4 ?m and Raman excitation at wavelengths as short as 300 nm. The probe is immersed in the sample and functions in the evanescent wave mode for both IR absorption and Raman scattering measurements. The sensing system makes possible the synergistic, and simultaneous, analysis of both IR and Raman data in an integrated device.
    Type: Grant
    Filed: June 13, 2008
    Date of Patent: December 21, 2010
    Assignee: University of South Florida
    Inventor: Nicholas Djeu
  • Patent number: 7789556
    Abstract: The present invention provides a dual-probe thermally compensated fluorescence decay rate temperature sensor capable of measuring the true temperature of a sample surface and its associated method of use.
    Type: Grant
    Filed: November 14, 2007
    Date of Patent: September 7, 2010
    Assignee: University of South Florida
    Inventor: Nicholas Djeu
  • Patent number: 7682147
    Abstract: A microlens is affixed in the far field of an optical fiber to spatially transform a beam either entering or exiting the fiber. In a first embodiment, a droplet of photo polymer is placed on the end of an optical fiber and the fiber is spun to create an artificial gravity. The droplet is cured by UV radiation during the spinning. In a second embodiment, nanoparticles are mixed into the droplet to increase the refractive index of the photo polymer. A third embodiment employs artificial gravity to attach a microsphere to the end of the optical fiber. A fourth embodiment chemically treats the surface of the microsphere so that the requirement of artificial gravity is either reduced or eliminated. In a fifth embodiment the droplet is cured under equilibrium or nonequilibrium conditions to obtain different final shapes for the lenslet. A sixth embodiment discloses fabrication of microlens arrays.
    Type: Grant
    Filed: October 6, 2006
    Date of Patent: March 23, 2010
    Assignee: University of South Florida
    Inventor: Nicholas Djeu
  • Publication number: 20080117951
    Abstract: The present invention provides a dual-probe thermally compensated fluorescence decay rate temperature sensor capable of measuring the true temperature of a sample surface and its associated method of use.
    Type: Application
    Filed: November 14, 2007
    Publication date: May 22, 2008
    Applicant: UNIVERSITY OF SOUTH FLORIDA
    Inventor: Nicholas Djeu
  • Publication number: 20070074655
    Abstract: A microlens is affixed in the far field of an optical fiber to spatially transform a beam either entering or exiting the fiber. In a first embodiment, a droplet of photo polymer is placed on the end of an optical fiber and the fiber is spun to create an artificial gravity. The droplet is cured by UV radiation during the spinning. In a second embodiment, nanoparticles are mixed into the droplet to increase the refractive index of the photo polymer. A third embodiment employs artificial gravity to attach a microsphere to the end of the optical fiber. A fourth embodiment chemically treats the surface of the microsphere so that the requirement of artificial gravity is either reduced or eliminated. In a fifth embodiment the droplet is cured under equlibrium or nonequilibrium conditions to obtain different final shapes for the lenslet. A sixth embodiment discloses fabrication of microlens arrays.
    Type: Application
    Filed: October 6, 2006
    Publication date: April 5, 2007
    Applicant: University of South Florida
    Inventor: Nicholas Djeu
  • Patent number: 7128943
    Abstract: A microlens is affixed in the far field of an optical fiber to spatially transform a beam either entering or exiting the fiber. In a first embodiment, a droplet of photo polymer is placed on the end of an optical fiber and the fiber is spun to create an artificial gravity. The droplet is cured by UV radiation during the spinning. In a second embodiment, nanoparticles are mixed into the droplet to increase the refractive index of the photo polymer. A third embodiment employs artificial gravity to attach a microsphere to the end of the optical fiber. A fourth embodiment chemically treats the surface of the microsphere so that the requirement of artificial gravity is either reduced or eliminated. In a fifth embodiment the droplet is cured under equlibrium or nonequilibrium conditions to obtain different final shapes for the lenslet. A sixth embodiment discloses fabrication of microlens arrays.
    Type: Grant
    Filed: February 20, 2003
    Date of Patent: October 31, 2006
    Assignee: University of South Florida
    Inventor: Nicholas Djeu
  • Patent number: 7104683
    Abstract: The present invention provides a thermally compensated fluorescence decay rate temperature sensor capable of measuring the true temperature of a sample surface and its associated method of use.
    Type: Grant
    Filed: August 11, 2005
    Date of Patent: September 12, 2006
    Assignee: University of South Florida
    Inventor: Nicholas Djeu
  • Publication number: 20060067379
    Abstract: The present invention provides a thermally compensated fluorescence decay rate temperature sensor capable of measuring the true temperature of a sample surface and its associated method of use.
    Type: Application
    Filed: August 11, 2005
    Publication date: March 30, 2006
    Applicant: UNIVERSITY OF SOUTH FLORIDA
    Inventor: Nicholas Djeu
  • Patent number: D859310
    Type: Grant
    Filed: November 29, 2018
    Date of Patent: September 10, 2019
    Inventors: Derek Djeu, Nicholas Djeu