Abstract: A laboratory system has demonstrated the measurement of three degrees of vibrational freedom simultaneously using a single beam through heterodyne speckle imaging. The random interference pattern generated by the illumination of a rough surface with coherent light can be exploited to extract information about the surface motion. The optical speckle pattern is heterodyne mixed with a coherent reference. The recorded optical data is then processed to extract three dimensions of surface motion. Axial velocity is measured by demodulating the received time-varying intensity of high amplitude pixels. Tilt, a gradient of surface velocity, is calculated by measuring speckle translation following reconstruction of the speckle pattern from the mixed signal.
Type:
Grant
Filed:
April 1, 2016
Date of Patent:
May 16, 2017
Assignee:
THE UNITED STATES OF AMERICA, AS REPRESENTED BY THE SECRETARY OF THE ARMY
Abstract: A method for laser-optical detection of a surface movement of a sample (1) is specified, whereby a first laser reference beam (10) is superimposed with a first laser measurement beam (12) directed onto the sample (1) and reflected by the latter in a first photorefractive/electro-optical element (4). In addition, a second reference beam (11) identical to the first reference beam (10) is superimposed with a second measurement beam (13) identical to the first measurement beam (12) in a second photorefractive/electro-optical element (5). Mutually inverse voltages are applied to the two photorefractive/electro-optical elements (4, 5). The light emerging from the photorefractive/electro-optical elements (4, 5) is converted into electric signals which are subtracted from one another prior to the signal evaluation. Also specified is an arrangement for implementing said method.
Type:
Grant
Filed:
October 30, 2013
Date of Patent:
May 16, 2017
Assignees:
Fill Gesellschaft m.b.H., Research Center for Non Destructive Testing GmbH
Abstract: An integrated optical circuit comprises a first waveguide section of a first material having a first index of refraction, a second waveguide section diffused with a second material, different from the first material, the second waveguide section having a second index of refraction; and a third waveguide section of the first material. A portion of the first waveguide section at a first interface is angled at a first angle and a portion of the second waveguide section is angled at the first angle. A portion of the first waveguide section at a second interface is angled at a second angle and a portion of the third waveguide section is angled at the second angle. The first angle and second angle are selected such that the angle of incidence of light at the first and second interfaces is greater than the Brewster's angle.
Abstract: A method for measuring a distance includes modulating the light beam at a first frequency, receiving a second beam by the optical detector to produce a first electrical signal having the first frequency and a first phase; modulating the light beam at a second frequency different than the first frequency; receiving the second beam by the optical detector to produce a second electrical signal having the second frequency and a second. After these steps, the retroreflector is moved while modulating the light beam continuously at the second frequency; and a first distance to the retroreflector is determined based at least in part on a the first and second frequencies and phases.
Type:
Grant
Filed:
November 16, 2015
Date of Patent:
April 25, 2017
Assignee:
FARO TECHNOLOGIES, INC
Inventors:
Robert E. Bridges, Lawrence B. Brown, James K. West, D. Scott Ackerson
Abstract: A method for measuring a distance includes modulating the light beam at a first frequency, receiving a second beam by the optical detector to produce a first electrical signal having the first frequency and a first phase; modulating the light beam at a second frequency different than the first frequency; receiving the second beam by the optical detector to produce a second electrical signal having the second frequency and a second. After these steps, the retroreflector is moved while modulating the light beam continuously at the second frequency; and a first distance to the retroreflector is determined based at least in part on a the first and second frequencies and phases.
Type:
Grant
Filed:
April 13, 2015
Date of Patent:
April 25, 2017
Assignee:
FARO TECHNOLOGIES, INC.
Inventors:
Robert E. Bridges, Lawrence B. Brown, James K. West, D. Scott Ackerson
Abstract: There is provided an optical tomographic observation device which has a resolving power which is higher than those of a conventional optical tomographic observation device and a confocal microscope by a simple configuration by applying a homodyne phase diversity detection technology and designing so as to satisfy the following formula when ? is a wavelength of a laser light source, ?? is a wavelength half width at half maximum, NA is a numerical aperture of an objective optical element, S is an effective area of a photodetector, and M is a detection magnification of a detection surface relative to a condensing surface. 1 NA 2 ? k 1 0.886 ? ? ?? ? ( NA ? 1 - NA 2 ) ? 0.901 ? S M 2 0.441 ? k 1 ? 0.
Abstract: A spectroscopy assembly having a first and a second optical ring resonator, each provided with a material having an intensity-dependent refraction index. The spectroscopy assembly further includes at least one waveguide, which is guided along the optical ring resonator at a distance such that the light of a continuous wave laser guided in the waveguide can be coupled into the optical ring resonator, and a frequency comb generated from the light of the continuous wave laser in the optical ring resonator can be coupled out of the waveguide. The optical ring resonators and the at least one waveguide are provided on a common substrate.
Type:
Grant
Filed:
April 27, 2012
Date of Patent:
April 11, 2017
Assignees:
MENLO SYSTEMS GMBH, ECOLE POLYTECHNIQUE FEDERALE DE LAUSANNE
Abstract: An apparatus (AS) measures positions of marks (202) on a lithographic substrate (W). An illumination arrangement (940, 962, 964) provides off-axis radiation from at least first and second regions. The first and second source regions are diametrically opposite one another with respect to an optical axis (O) and are limited in angular extent. The regions may be small spots selected according to a direction of periodicity of a mark being measured, or larger segments. Radiation at a selected pair of source regions can be generated by supplying radiation at a single source feed position to a self-referencing interferometer. A modified half wave plate is positioned downstream of the interferometer, which can be used in the position measuring apparatus. The modified half wave plate has its fast axis in one part arranged at 45° to the fast axis in another part diametrically opposite.
Abstract: A mirror (M) of a projection exposure apparatus for microlithography configured for structured exposure of a light-sensitive material and a method for producing a mirror (M). The mirror (M) has a substrate body (B), a first mirror surface (S) and a second mirror surface (S?). The first mirror surface (S) is formed on a first side (VS) of the substrate body (B). The second mirror surface (S?) is formed on a second side (RS) of the substrate body (B), the second side being different from the first side of the substrate body (B). The mirror (M) may be embodied, in particular, such that the substrate body (B) is produced from a glass ceramic material.
Type:
Grant
Filed:
February 6, 2012
Date of Patent:
March 28, 2017
Assignee:
Carl Zeiss SMT GmbH
Inventors:
Jochen Hetzler, Ralf Mueller, Wolfgang Singer
Abstract: Systems for imaging a sample are provided. The system includes an OCT imaging portion having an associated OCT path defined by one set of optical elements between an OCT signal delivery optical fiber and the sample; an image capture portion having an associated image capture path defined by a second set of optical elements between an image capture device and the sample; and an illuminator portion having an associated illumination path defined by a third set of optical elements between an illumination source and the sample. The OCT path, the image capture path, and the illuminator path have at least one optical element in common, and the respective paths differ from each other by at least one optical element. The illumination path includes a multi-wavelength source of optical radiation.
Type:
Grant
Filed:
February 26, 2016
Date of Patent:
March 7, 2017
Assignee:
Bioptigen, Inc.
Inventors:
Eric L. Buckland, Bradley A. Bower, Robert H. Hart, Pete Huening
Abstract: A resonator fiber optic gyroscope comprises a master laser that emits a reference optical signal, a first slave laser that emits a clockwise optical signal, and a second slave laser that emits a counter-clockwise optical signal. A resonator ring cavity in optical communication with the first slave laser and second slave laser is configured to receive the optical signals from the slave lasers without receiving the reference optical signal. A reflected optical signal from the cavity is directed to a feedback laser stabilization loop for the master laser that includes a common modulation frequency scheme. A frequency of the optical signal from the master laser is indirectly locked onto a resonance frequency of the cavity with a fixed frequency offset, which is determined by a relative frequency between the optical signal of the first slave laser or the second slave laser, and the optical signal of the master laser.
Type:
Grant
Filed:
June 23, 2014
Date of Patent:
March 7, 2017
Assignee:
Honeywell International Inc.
Inventors:
Lee K. Strandjord, Glen A. Sanders, Tiequn Qiu
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
Abstract: The present invention provides an angular velocity detection method adopting a bi-directional full reciprocal coupling optoelectronic oscillator, which is implemented on an optical carrier microwave gyroscope. The optical carrier microwave gyroscope is a bi-directional resonant optical carrier microwave angular velocity measurement device sharing one optical fiber loop. The core of the method lies in that the Sagnac effect is sensed using a bi-directional optical carrier microwave resonant cavity, where the optical carrier microwave resonant cavity employs a coupling optoelectronic oscillator to achieve a bi-directional full reciprocal optical fiber path, and non-reciprocity error of the resonant cavity is eliminated effectively. The angular velocity detection method has features of high-precision, easy implementation and low costs.
Abstract: Disclosed are improved optical detection methods comprising multiplexed interferometric detection systems and methods for determining a characteristic property of a non-aqueous sample, together with various applications of the disclosed techniques.
Type:
Grant
Filed:
February 22, 2012
Date of Patent:
February 7, 2017
Assignee:
Vanderbilt University
Inventors:
Darryl J. Bornhop, Robert A. Flowers, Esther Pesciotta Miller
Abstract: Frequency domain optical coherence imaging systems have an optical source, an optical detector and an optical transmission path between the optical source and the optical detector. The optical transmission path between the optical source and the optical detector reduces an effective linewidth of the imaging system. The optical source may be a broadband source and the optical transmission path may include a periodic optical filter.
Type:
Grant
Filed:
June 24, 2011
Date of Patent:
February 7, 2017
Assignee:
Bioptigen, Inc.
Inventors:
Joseph A. Izatt, Eric L. Buckland, William J. Brown
Abstract: An integrated apertured micromirror is provided in which the micromirror is monolithically integrated with a micro-optical bench fabricated on a substrate using a lithographic and deep etching technique. The micromirror has an aperture therein and is oriented such that the micromirror is optically coupled to receive an incident beam having an optical axis in a plane of the substrate and to at least partially transmit the incident beam therethrough via the aperture.
Type:
Grant
Filed:
March 14, 2014
Date of Patent:
January 31, 2017
Assignee:
SI-WARE SYSTEMS
Inventors:
Yasser M. Sabry, Diaa Abdel Maged Khalil, Mohamed Sadek
Abstract: The present invention relates to systems and methods for quantitative three-dimensional mapping of refractive index in living or non-living cells, tissues, or organisms using a phase-shifting laser interferometric microscope with variable illumination angle. A preferred embodiment provides tomographic imaging of cells and multicellular organisms, and time-dependent changes in cell structure and the quantitative characterization of specimen-induced aberrations in high-resolution microscopy with multiple applications in tissue light scattering.
Type:
Grant
Filed:
September 18, 2014
Date of Patent:
January 17, 2017
Assignee:
Massachusetts Institute of Technology
Inventors:
Wonshik Choi, Ramachandra Dasari, Christopher Fang-Yen, Michael Feld
Abstract: A fiber-optic Sagnac interferometer in a rotation rate sensor comprises a multifunctional integrated optical chip (MIOC) with a MIOC transfer function. A digital filter is connected upstream to the multi-functional integrated optical chip, whose filter transfer function corresponds basically to the inverse MIOC transfer function such that the MIOC transfer function is compensated by the filter transfer function. Corresponding coefficients of the filter transfer function may be determined in a main control loop.
Abstract: A compact, balanced, up to three degrees of freedom measuring interferometer having dual beam splitters rotated ninety degrees with respect to each other and a measurement detector including a quadrant detector or multi-core fiber with four detectors which enables fiber delivery of an optical source without periodic error, an interferometer system, and method for using is disclosed.
Type:
Grant
Filed:
November 29, 2012
Date of Patent:
December 13, 2016
Assignees:
University of Rochester, Delft University of Technology
Inventors:
Jonathan D. Ellis, Josephus Wilhelmus Spronck
Abstract: A method determines a distance with a specified accuracy. The method transmits to an interferometer a test signal oscillating with a test frequency and receives, in response to the transmitting, an interferometric signal formed by interfering the test signal with a delayed signal produced by delaying a copy of the test signal over the distance equal to a path length difference in the interferometer. The test frequency is varying such that the test signal oscillates with different values of the test frequency. The method determines at least two values of the test frequency corresponding to particular values of the interferometric signal by beating the test signal with a reference signal having a reference frequency, wherein a value of the reference frequency is an absolute value predetermined with the specified accuracy. The method determines the distance using the two values of the test frequency.
Type:
Grant
Filed:
December 21, 2013
Date of Patent:
November 29, 2016
Assignee:
MagiQ Technologies, Inc.
Inventors:
Caleb A Christensen, Anton Zavriyev, A. Craig Beal