Patents Assigned to Axsun Technologies, LLC
  • Patent number: 9772177
    Abstract: Optical coherence tomography (OCT) probe and system designs are disclosed that minimize the effects of mechanical movement and strain to the probe to the OCT analysis. It also concerns optical designs that are robust against noise from the OCT laser source. Also integrated OCT system-probes are included that yield compact and robust electro-opto-mechanical systems along with polarization sensitive OCT systems.
    Type: Grant
    Filed: August 7, 2012
    Date of Patent: September 26, 2017
    Assignee: Axsun Technologies LLC
    Inventors: Bartley C. Johnson, Dale C. Flanders
  • Patent number: 9696471
    Abstract: An integrated swept wavelength optical source uses a filtered ASE signal with an optical amplifier and tracking filter. This source comprises a micro optical bench, a source for generating broadband light, a first tunable Fabry Perot filter, installed on the bench, for spectrally filtering the broadband light from the broadband source to generate a narrowband tunable signal, an amplifier, installed on the bench, for amplifying the tunable signal, and a second tunable Fabry Perot filter, installed on the bench, for spectrally filtering the amplified tunable signal from the amplifier. A self-tracking arrangement is also possible where a single tunable filter both generates the narrowband signal and spectrally filters the amplified signal. In some examples, two-stage amplification is provided. The use of a single bench implementation yields a low cost high performance system. For example, polarization control between components is no longer necessary.
    Type: Grant
    Filed: March 20, 2013
    Date of Patent: July 4, 2017
    Assignee: Axsun Technologies LLC
    Inventors: Dale C. Flanders, Walid A. Atia, Mark E. Kuznetsov
  • Patent number: 9593934
    Abstract: An optical coherence analysis system comprising: a first swept source that generates a first optical signal that is tuned over a first spectral scan band, a second swept source that generates a second optical signal that is tuned over a second spectral scan band, a combiner for combining the first optical signal and the second optical signal for form a combined optical signal, an interferometer for dividing the combined optical signal between a reference arm leading to a reference reflector and a sample arm leading to a sample, and a detector system for detecting an interference signal generated from the combined optical signal from the reference arm and from the sample arm. In embodiments, the swept sources are tunable lasers that have shared laser cavities.
    Type: Grant
    Filed: February 7, 2014
    Date of Patent: March 14, 2017
    Assignee: Axsun Technologies LLC
    Inventors: Brian Goldberg, Dale C. Flanders, Walid A. Atia, Bartley C. Johnson, Mark E. Kuznetsov
  • Patent number: 9574869
    Abstract: An optical coherence analysis system comprising: a first swept source that generates a first optical signal that is tuned over a first spectral scan band, a second swept source that generates a second optical signal that is tuned over a second spectral scan band, a combiner for combining the first optical signal and the second optical signal to form a combined optical signal, an interferometer for dividing the combined optical signal between a reference arm leading to a reference reflector and a sample arm leading to a sample, and a detector system for detecting an interference signal generated from the combined optical signal from the reference arm and from the sample arm.
    Type: Grant
    Filed: January 21, 2014
    Date of Patent: February 21, 2017
    Assignee: Axsun Technologies LLC
    Inventors: Bartley C. Johnson, Walid Atia, Mark E. Kuznetsov, Dale C. Flanders
  • Patent number: 9441944
    Abstract: An optical coherence analysis system uses a laser swept source that is constrained to operate in a mode locked condition using regenerative mode-locking. This is accomplished by synchronously changing the laser cavity's net gain and/or phase based on time varying intensity of the swept optical signal generated by the laser. This produces a stable pulsation behavior, which is associated with smooth tuning (low optical frequency reference clock jitter) and low relative intensity noise (RIN).
    Type: Grant
    Filed: May 16, 2012
    Date of Patent: September 13, 2016
    Assignee: Axsun Technologies LLC
    Inventors: Mark E. Kuznetsov, Bartley C. Johnson
  • Patent number: 9417051
    Abstract: A frequency swept laser source for TEFD-OCT imaging includes an integrated clock subsystem on the optical bench with the laser source. The clock subsystem generates frequency clock signals as the optical signal is tuned over the scan band. Preferably the laser source further includes a cavity extender in its optical cavity between a tunable filter and gain medium to increase an optical distance between the tunable filter and the gain medium in order to control the location of laser intensity pattern noise. The laser also includes a fiber stub that allows for control over the cavity length while also controlling birefringence in the cavity.
    Type: Grant
    Filed: September 17, 2013
    Date of Patent: August 16, 2016
    Assignee: Axsun Technologies LLC
    Inventors: Dale C. Flanders, Walid Atia, Bartley C. Johnson, Mark E. Kuznetsov, Carlos R. Melendez
  • Patent number: 9337619
    Abstract: A frequency swept laser source that generates an optical signal that is tuned over a spectral scan band at single discrete wavelengths associated with longitudinal modes of the swept laser source. Laser hopping over discrete single cavity modes allows long laser coherence length even under dynamic very high speed tuning conditions. A ramp drive to the laser is used to linearize laser frequency tuning. A beam splitter is used to divide the optical signal between a reference arm leading to a reference reflector and a sample arm leading to a sample. A detector system detects the optical signal from the reference arm and the sample arm for generating depth profiles and images of the sample.
    Type: Grant
    Filed: October 12, 2011
    Date of Patent: May 10, 2016
    Assignee: Axsun Technologies LLC
    Inventors: Walid Atia, Mark E. Kuznetsov, Dale C. Flanders
  • Patent number: 9316483
    Abstract: An optical coherence tomography system utilizes an optical swept laser that has improved coherence length in the swept optical signal. This is accomplished using an intra-cavity element that extracts the tunable optical signal at the optimal location within the laser's resonant cavity. Generally this location is between the intracavity tuning element and the cavity's gain element so that light coming from the tuning element is extracted. In general in lasers, the gain element adds noise and chirp and this degrades the tunable optical signal's coherence length.
    Type: Grant
    Filed: December 31, 2013
    Date of Patent: April 19, 2016
    Assignee: Axsun Technologies LLC
    Inventor: Dale C. Flanders
  • Patent number: 9310182
    Abstract: A system and method for spectral filtering of a k-clock signal in a swept-source Optical Coherence Tomography (“OCT”) system to remove artifacts in the k-clock signal. The system synchronizes sampling of the k-clock and interference signals generated from scanning a sample. Using a filtered k-clock signal, the system resamples an interference dataset of the interference signals. The system then performs Fourier transform based processing upon the resampled interference dataset to yield axial depth images of the sample. The system preferably performs the reconstruction, resampling, and associated Fourier-Domain signal processing in software via a Field Programmable Gate Array (“FPGA”) of a rendering system.
    Type: Grant
    Filed: December 30, 2013
    Date of Patent: April 12, 2016
    Assignee: Axsun Technologies LLC
    Inventors: Brian Goldberg, Bartley C. Johnson
  • Patent number: 9243885
    Abstract: An optical coherence tomography system utilizes an optical swept source that frequency scans at least two different sweep rates. In this way, the system can perform large depth scans of the sample and then the same system can perform shorter depth high precision scans, in one specific example. In order to optimally use the analog to digital converter that samples the interference signal, the system further samples the interference signals at different optical frequency sampling intervals depending upon the selected sweep rates of the optical swept source. This allows the system to adapt to different sweep rates in an optimal fashion.
    Type: Grant
    Filed: October 12, 2012
    Date of Patent: January 26, 2016
    Assignee: Axsun Technologies, LLC
    Inventors: Bartley C. Johnson, Brian Goldberg, Dale C. Flanders