Patents Examined by Andrew H. Lee
  • Patent number: 7193726
    Abstract: An interferometry system includes an interferometer to split an input beam into a measurement beam and at least one other beam. The interferometer directs the measurement beam along a measurement path that includes at least two passes to a measurement object, and overlaps the measurement beam with the other beam after the measurement beam completes the at least two passes. The path of the measurement beam is sheared during the first and second passes when the measurement object moves along a direction orthogonal to a portion of the measurement path that contacts the measurement object. The interferometry system includes optics to redirect the measurement beam after the first pass and before the second pass so that shear imparted during the second pass cancels shear imparted during the first pass.
    Type: Grant
    Filed: August 23, 2002
    Date of Patent: March 20, 2007
    Assignee: Zygo Corporation
    Inventor: Henry A. Hill
  • Patent number: 7154612
    Abstract: In a method for calibrating a radius test bench for measuring radii of optical elements, in particular of lenses and spherical mirrors, there are provided an illuminating system 1 that generates a spherical wave and a diffractive optical element 3 that retroreflects a spherical wave of a specific radius into itself. The diffractive optical element 3 is introduced into the radius test bench in at least two positions, a first position thereof being a cat's eye position 1 and another position being an autocollimation position, as a result of which it is possible to use the radius of curvature simulated by the diffractive optical element 3 to detect deviations of the radius test bench from this radius of curvature as errors of the radius test bench, and thus to take them into account in the measurements of optical elements to be tested.
    Type: Grant
    Filed: April 22, 2003
    Date of Patent: December 26, 2006
    Assignee: Carl Zeiss SMT AG
    Inventor: Rolf Freimann
  • Patent number: 7123364
    Abstract: An imaging system includes: an object wavefront source and an optical microscope objective all positioned to direct an object wavefront onto an area of a vibrating subject surface encompassed by a field of view of the microscope objective, and to direct a modulated object wavefront reflected from the encompassed surface area through a photorefractive material; and a reference wavefront source and at least one phase modulator all positioned to direct a reference wavefront through the phase modulator and to direct a modulated reference wavefront from the phase modulator through the photorefractive material to interfere with the modulated object wavefront. The photorefractive material has a composition and a position such that interference of the modulated object wavefront and modulated reference wavefront occurs within the photorefractive material, providing a full-field, real-time image signal of the encompassed surface area.
    Type: Grant
    Filed: October 8, 2002
    Date of Patent: October 17, 2006
    Assignee: Battelle Energy Alliance, LLC
    Inventors: Vance A. Deason, Kenneth L. Telschow
  • Patent number: 7106455
    Abstract: There is provided an interferometer for measuring a surface shape of an optical element using interference, including a reference wave-front generating unit for generating a reference wave front for measuring the surface shape, which is provided in a target optical path, and includes an Alvarez lens.
    Type: Grant
    Filed: March 6, 2002
    Date of Patent: September 12, 2006
    Assignee: Canon Kabushiki Kaisha
    Inventors: Akiyoshi Suzuki, Yoshiyuki Sekine
  • Patent number: 7068372
    Abstract: The interferometer comprises a beam splitter, a mirror and a phase modulator. The beam splitter splits a signal into a first portion and a second portion. The mirror reflects the first portion. The first portion includes an optical path length, which is fixed. The phase modulator includes a selectively actuated reflective element to reflect the second portion. The second portion includes an optical path length, which is variable. The reflective element is selectively actuated between a first position and a second position to vary the optical path length of the second portion. When the reflective element is in the first position, the first portion and the second portion constructively interfere thereby directing the component signal along a first output path. When the reflective element is in the second position, the first portion and the second portion destructively interfere thereby directing the component signal along a second optical path.
    Type: Grant
    Filed: January 28, 2003
    Date of Patent: June 27, 2006
    Assignee: Silicon Light Machines Corporation
    Inventors: Jahja I. Trisnadi, Clinton B. Carlisle
  • Patent number: 7064842
    Abstract: An optical displacement sensor comprises a surface emitting laser light source, a scale and a photosensor. The surface emitting laser light source emits a light beam having a predetermined shape. The scale is displaceable in such a manner as to cross the light beam emitted from the surface emitting laser light source and has a diffraction grating of a predetermined period formed thereon for forming a diffraction interference pattern from the light beam. The photosensor receives a predetermined portion of the diffraction interference pattern.
    Type: Grant
    Filed: January 10, 2000
    Date of Patent: June 20, 2006
    Assignee: Olympus Optical Co., Ltd.
    Inventors: Eiji Yamamoto, Jun Hane, Iwao Komazaki
  • Patent number: 7057741
    Abstract: A system for inspecting specimens such as semiconductor wafers is provided. The system provides scanning of dual-sided specimens using a diffraction grating that widens and passes nth order (n>0) wave fronts to the specimen surface and a reflective surface for each channel of the light beam. Two channels and two reflective surfaces are preferably employed, and the wavefronts are combined using a second diffraction grating and passed to a camera system having a desired aspect ratio. The system preferably comprises a damping arrangement which filters unwanted acoustic and seismic vibration, including an optics arrangement which scans a first portion of the specimen and a translation or rotation arrangement for translating or rotating the specimen to a position where the optics arrangement can scan the remaining portion(s) of the specimen. The system further includes means for stitching scans together, providing for smaller and less expensive optical elements.
    Type: Grant
    Filed: April 5, 2000
    Date of Patent: June 6, 2006
    Assignee: KLA-Tencor Corporation
    Inventors: Dieter Mueller, Daniel Ivanov Kavaldjiev, Rainer Schierle
  • Patent number: 7042574
    Abstract: Methods and apparatus for reducing the effects of non-isotropic gas distributions on interferometry measurements are disclosed.
    Type: Grant
    Filed: December 3, 2002
    Date of Patent: May 9, 2006
    Assignee: Zygo Corporation
    Inventor: Henry A. Hill
  • Patent number: 7038787
    Abstract: Systems and methods are described for content-based fused off-axis illumination direct-to-digital holography. A method includes calculating an illumination angle with respect to an optical axis defined by a focusing lens as a function of data representing a Fourier analyzed spatially heterodyne hologram; reflecting a reference beam from a reference mirror at a non-normal angle; reflecting an object beam from an object the object beam incident upon the object at the illumination angle; focusing the reference beam and the object beam at a focal plane of a digital recorder to from the content-based off-axis illuminated spatially heterodyne hologram including spatially heterodyne fringes for Fourier analysis; and digitally recording the content based off-axis illuminated spatially heterodyne hologram including spatially heterodyne fringes for Fourier analysis.
    Type: Grant
    Filed: September 3, 2002
    Date of Patent: May 2, 2006
    Assignee: UT-Battelle, LLC
    Inventor: Jeffery R. Price
  • Patent number: 7038782
    Abstract: An apparatus for locking the wavelength of a laser uses a non-planar etalon, for example a non-parallel etalon, to produce a periodic spatial interference pattern, typically in the light reflected from the etalon. The apparatus also uses a detector to detect the spatial interference pattern having at least three separate detector elements, commonly referred to as pixels. The etalon and the detector are matched to each other so that adjacent pixels detect a specific portion of the phase of the periodic interference pattern.
    Type: Grant
    Filed: December 11, 2001
    Date of Patent: May 2, 2006
    Assignee: ADC Telecommunications, Inc.
    Inventors: Gunnar Hedin, Johan Erik Fredrik Tegin
  • Patent number: 7030990
    Abstract: A spectrometer for determining the concentration of a substance within a sample comprises a. a radiation source (11) for supplying radiation to the sample to be measured; b. a filter (15) for filtering radiation transmitted by the sample, the filter having a number of pass bands at wavelengths corresponding to absorption peaks in the absorption spectrum of the sample to be detected, the filter being responsive to an applied signal to modulate the wavelengths of the pass bands; and, c. a detector (16) for detecting the filtered radiation, the detector being responsive to the applied signal to determine the relative intensities of the maxima and minima in the absorption spectra of the substance, characterized in that the radiation source is selectively activated in response to the applied signal.
    Type: Grant
    Filed: February 20, 2001
    Date of Patent: April 18, 2006
    Assignee: Bah Holdings, LLC
    Inventor: Constantine Dean Capetanopoulos
  • Patent number: 7016048
    Abstract: A phase-resolved functional optical coherence tomography system simultaneously obtains the Stokes vectors, structure, blood flow velocity, standard deviation, and birefringence images in human skin. The multifunctional images were obtained by processing the analytical interference fringe signals derived from the two perpendicular polarization detection channels. The blood flow velocity and standard deviation images were obtained by comparing the phase from the pairs of analytical signals in the neighboring A-lines in the same polarization state. The Stokes vectors were obtained by processing the analytical signals from two polarization diversity detection channels for the same reference polarization state. From the four Stokes vectors, the birefringence image, which is insensitive to the orientations of the optical axis in the sample, was obtained. Multifunctional images of a port wine stain birthmark in human skin are demonstrated.
    Type: Grant
    Filed: April 9, 2003
    Date of Patent: March 21, 2006
    Assignee: The Regents of the University of California
    Inventors: Zhongping Chen, J. Stuart Nelson
  • Patent number: 7016025
    Abstract: Characterization of an optical system is quickly and easily obtained in a single acquisition step by obtaining image data within a volume of image space. A reticle and image plane are positioned obliquely with respect to each other such that a reticle having a plurality of feature sets thereon, including periodic patterns or gratings, is imaged in a volume of space, including the depth of focus. Metrology tools are used to analyze the detected or recorded image in the volume of space through the depth of focus in a single step or exposure to determine the imaging characteristics of an optical system. Focus, field curvature, astigmatism, spherical, coma, and/or focal plane deviations may be determined. The present invention is particularly applicable to semiconductor manufacturing and photolithographic techniques used therein, and is able to quickly characterize an optical system in a single exposure with dramatically increased data quality and continuous coverage of the full parameter space.
    Type: Grant
    Filed: June 24, 1999
    Date of Patent: March 21, 2006
    Assignee: ASML Holding N.V.
    Inventor: Matthew E. Hansen
  • Patent number: 7012697
    Abstract: An optical heterodyne detection system includes an attenuator for attenuating an input signal before the input signal is combined with a local oscillator signal. An optimal attenuation level for the input signal, which improves the signal to noise ratio of the heterodyne beat signal, is determined by obtaining a base measurement of an output signal in response to the local oscillator signal and in the absence of the input signal, obtaining sample measurements of the output signal in response to the input signal as a function of different attenuation levels, and determining the optimal attenuation level as a function of the base measurement and the sample measurements. A minimum attenuation level for the input signal, which protects receiver photodetectors from being saturated or damaged, is determined by setting an initial attenuation level and gradually reducing the attenuation level until the voltage limit of the photodetectors is reached.
    Type: Grant
    Filed: October 24, 2002
    Date of Patent: March 14, 2006
    Assignee: Agilent Technologies, Inc.
    Inventors: William Ian McAlexander, Douglas M. Baney
  • Patent number: 7012696
    Abstract: The disclosure relates to optical heterodyne detection cavity ringdown spectroscopy. In one aspect the disclosure relates to an optical system comprising a ringdown cavity cell defining a resonant optical cavity, means for directing coherent light selected from the group consisting of continuous or quasi-continuous light into said optical cavity, means for altering the resonant optical cavity so as to generate a frequency shift of the coherent light in the optical cavity, means for coupling said coherent light into the optical cavity and means for decoupling the frequency shifted coherent light out of said optical cavity, means for optically combining said decoupled frequency shifted coherent light with another portion of coherent light not in optical communication with the optical cavity and means for optical heterodyne detection of the intensity of said combined light. A method for optical detection is also described as well as methods and apparatus for detecting a parameter of a sample.
    Type: Grant
    Filed: July 12, 2001
    Date of Patent: March 14, 2006
    Assignee: Macquarie Research Ltd.
    Inventors: Brian J. Orr, Yabai He
  • Patent number: 7009691
    Abstract: By making combined interferometric and polarimetric measurements on a device under test, the relative phase uncertainty in device characterizations performed with a polarimeter or polarization analyzer alone is removed. This allows determination of the group delay to within a constant offset and the chromatic dispersion of the device under test.
    Type: Grant
    Filed: May 29, 2002
    Date of Patent: March 7, 2006
    Assignee: Agilent Technologies, Inc.
    Inventors: Gregory D. VanWiggeren, Douglas M. Baney
  • Patent number: 7009700
    Abstract: A method and device for obtaining a sample with three-dimensional microscopy, in particular a thick biological sample and the fluorescence field emitted by the sample. One embodiment includes obtaining interferometric signals of a specimen, obtaining fluorescence signals emanating from the specimen, recording these signals, and processing these signals so as to reconstruct three-dimensional images of the specimen and of the field of fluorescence emitted by the specimen at a given time.
    Type: Grant
    Filed: December 18, 2003
    Date of Patent: March 7, 2006
    Assignee: Universite Libre De Bruxelles
    Inventors: Frank Dubois, Catherine Yourassowski
  • Patent number: 6980298
    Abstract: A system for determining at least one condition of a seal including an optical fiber for transmitting light from a light source. The optical fiber is embedded in the seal and operatively coupled to an interferometric system. The interferometric system is operatively coupled to a processor. The interferometric system provides the processor with information relating to wear of the optical fiber, and the processor determines wear of the seal, rate of wear and remaining useful life of the seal based on the information relating to wear of the optical fiber.
    Type: Grant
    Filed: May 6, 2003
    Date of Patent: December 27, 2005
    Assignee: Reliance Electric Technologies, LLC
    Inventor: Frederick M. Discenzo
  • Patent number: 6970252
    Abstract: Low-coherence interferometric device for light optical depth scanning of an object (13) positioned in front of a measurement aperture (12) of the device by detecting the position of light-reflecting sites which are located at different measurement depths within the object (13) along a scanning path (19) running into the object in a scanning direction (25) using a low-coherence interferometer which comprises a low-coherence light source (7), a beam splitter (8), a reference reflector (9) and a detector (10). The interferometer is a free-space in-line interferometer (6) having a beam splitter (8) running transversal to the direction of scanning (25). The light transmitter (7), the detector (10) and the reference mirror (9) are arranged on the side of the beam splitter facing away from the measurement aperture. A movable scanning lens (11) is arranged between the beam splitter (8) and the measurement aperture (12).
    Type: Grant
    Filed: June 19, 2001
    Date of Patent: November 29, 2005
    Inventor: Alexander Knüttel
  • Patent number: 6970249
    Abstract: A device for measuring simultaneously the phase at each point of an image formed by light reflected from a sample in which the phase has been modified by plasma resonance in a thin conducting layer, the device comprising a thick transparent substrate (10) on which a thin layer of conducting material is deposited (13); a light source (1); an interferometer; an imaging means (9); and a processing means.
    Type: Grant
    Filed: September 12, 2000
    Date of Patent: November 29, 2005
    Assignee: Proteoptics, Ltd.
    Inventors: Stephen Lipson, Ariel Notcovich