Schlieren Effect Patents (Class 356/129)
  • Patent number: 10073028
    Abstract: An optical head assembly for use in a spectrometer is provided that is configured to characterize one or more constituents within a sample gas. The assembly includes a thermoelectric cooler (TEC) having a cold side on one end and a hot side on an opposite end, a cold plate in thermal communication with the cold side of the TEC, a hot block in thermal communication with the hot side of the TEC, a light source in thermal communication with the cold plate such that a change in temperature of the TEC causes one or more properties of the light source (e.g., wavelength, etc.) to change, and an optical element in thermal communication with the cold plate positioned to collimate light emitted by the light source through the sample gas (such that properties of the optical element vary based on a change in temperature of the TEC).
    Type: Grant
    Filed: September 1, 2015
    Date of Patent: September 11, 2018
    Assignee: SpectraSensors, Inc.
    Inventors: Joshua Cohen, Nathan St. John, Alfred Feitisch
  • Patent number: 9599497
    Abstract: The present invention is a system and method of visualizing fluid flow around an object, such as an aircraft or wind turbine, by aligning the object between an imaging system and a celestial object having a speckled background, taking images, and comparing those images to obtain fluid flow visualization.
    Type: Grant
    Filed: July 29, 2015
    Date of Patent: March 21, 2017
    Assignee: The United States of America as Represented by the Administrator of the National Aeronautics and Space Administration
    Inventors: Edward A Haering, Jr., Michael A Hill
  • Patent number: 9494533
    Abstract: Optical quality control system for controlling the quality of a high refractive index solid (2), comprising a container (4) configured to receive the solid therein, a structured light source (30), an optical inspection zone configured for receiving an optical device (10) or an eye of a human observer, and a high refractive index liquid (12) for insertion in the container in a volume sufficient to fully immerse the translucent solid. The structured light source is configured to project a planar light fan (20) through the high refractive index solid immersed in the high refractive index liquid generating a illuminated cross-section (18) in the solid. The optical inspection zone is arranged at a top end of the container adapted for inspection of the illuminated cross-section in a direction transverse to a plane (P) defined by the planar illuminated cross-section.
    Type: Grant
    Filed: October 29, 2013
    Date of Patent: November 15, 2016
    Assignee: Scientific Visual SA
    Inventors: Ivan Orlov, Yury Kuzminykh
  • Patent number: 9140641
    Abstract: A fluid analysis method is provided. A gradient distribution of a first scalar property of a calibration fluid in a space is obtained. A calibration schlieren image of the calibration fluid is acquired and processed to obtain an intensity distribution of the calibration schlieren image. The gradient distribution of the first scalar property of the calibration fluid in the space is mapped to the intensity distribution of the calibration schlieren image, so as to obtain a corresponding relation between the gradients of the first scalar property and the intensities. A test schlieren image of a test fluid is acquired and processed to obtain intensity distribution of the test schlieren image. The intensity distribution of the test schlieren image is converted to the gradient distribution of the first scalar property of the test fluid according to the corresponding relation. Moreover, a fluid analysis system is also provided.
    Type: Grant
    Filed: December 20, 2013
    Date of Patent: September 22, 2015
    Assignee: National Taiwan University
    Inventors: Chen-Li Sun, Tzu-Hsun Hsiao, Chien-Yuan Huang
  • Patent number: 8462326
    Abstract: The invention discloses the Schlieren type ultrasonic wave observer system. The invention states optics interference by the ultrasonic wave sound field after perturbation the medium, and combines to make the interference penetration optical projection the image, the goal lies in the observation ordinary naked eye blind ultrasonic wave sound field distribution. Characteristic of the invention using the spectroscope and the reflector combination, as well as microcontroller precise time delay control, might formerly be limited under the 4F optical field length limit to enhance largely the field of vision the several fold.
    Type: Grant
    Filed: January 10, 2011
    Date of Patent: June 11, 2013
    Assignee: Chang Gung University
    Inventors: Hao-Li Liu, Chung-Cheng Kung, Ting-Chia Chang
  • Patent number: 8269956
    Abstract: An optical element for resonating and reflecting incident light having a wavelength includes a periodic structure formed of protrusions and recessions. A period of the periodic structure is equal to or less than the wavelength of the incident light. The incident light having the wavelength is resonated and reflected by a resonance caused between the incident light and the protrusions and recessions. Widths of the protrusions are spatially changed.
    Type: Grant
    Filed: July 9, 2009
    Date of Patent: September 18, 2012
    Assignee: Ricoh Company, Ltd.
    Inventors: Tsuyoshi Hashiguchi, Hideaki Hirai
  • Patent number: 8239144
    Abstract: A portable liquid design system includes a portable information handling system (IHS) that employs a liquid design application capable of operating in different modes to design different liquids such as corn syrup, espresso, coffee, soda pop and others. The portable liquid design system may include a refractometer to measure the refractive index and temperature of a liquid under test. The liquid design application may apply the measured refractive index and temperature to a 3 dimensional representation of the correlation of refractive index, temperature and concentration (% total dissolved solids) to determine a particular concentration corresponding to the measured refractive index and temperature. A single 3 dimensional scale may apply to virtually all values of interest of refractive index, temperature and concentration for a particular liquid under test.
    Type: Grant
    Filed: March 31, 2010
    Date of Patent: August 7, 2012
    Assignee: Voice Systems Technology, Inc.
    Inventor: Vincent Fedele
  • Patent number: 8107061
    Abstract: In a schlieren optical system, a laser beam is passed through the jet flow and the ambient around the jet flow, and a high speed sampling is performed using a high speed photo sensor while displacing measurement points. The value obtained by sampling represents a result of the optical path caused curved by a density gradient generated in an arc-shape from the center of the jet flow. The value is subjected to a high speed discrete Fourier transform and decomposed into frequency components which constitute the noise. Thereafter, Abel inversion is performed on data belonging to a particular frequency to obtain a density gradient in the radial direction from the center of the jet flow. The obtained density gradient is visualized in a graph display, so that the position of the sound source and the state of the jet flow can be accurately grasped.
    Type: Grant
    Filed: January 8, 2010
    Date of Patent: January 31, 2012
    Assignees: National University Corporation Gunma University, Japan Aerospace Exploration Agency
    Inventors: Mikiya Araki, Yusuke Sone, Takayuki Kojima, Hideyuki Taguchi, Seiichi Shiga, Tomio Obokata
  • Publication number: 20090128803
    Abstract: An optical indicator (130) for identification of a changed state of a fluid with respect to a reference state of the same fluid, or for monitoring or checking or authenticating a fluid. The fluid has an optical parameter that changes with the change of the state of the fluid. The optical indicator (130) may be attached to or integral with a container or packaging (132) for the fluid. The indicator (130) includes a cavity configured to be filed with the fluid such that the fluid filled cavity forms a variable optical element having an optical performance that varies depending on the changeable fluid's optical parameter. The fluid filled cavity coupled to other optical components of the indicator provides an image that may be compared to a reference image to detect a change of at least one optical property of the fluid as compared to the reference fluid. The comparison may be performed visually or by a suitable detector. The comparison may include automated processing of the detector's output signal(s).
    Type: Application
    Filed: April 19, 2005
    Publication date: May 21, 2009
    Applicant: QUALISENSE TECHNOLOGIES LTD.
    Inventor: Livne Gan
  • Publication number: 20080144018
    Abstract: An apparatus rapidly reads out wavefront errors of an input wavefront and includes a holographic optical element (HOE), a position readout detector and a readout device. The HOE receives the input wavefront and includes a hologram of a particular wavefront recorded with reference waves, each defining a particular aberration coefficient. The position readout detector includes a plurality of position sensing devices (PSDs) receiving an optical output of the HOE, each PSD sensing the occurrence and magnitude in the input wavefront of any of the particular aberrations defined by the reference waves recorded to the holographic optical element with the particular wavefront. The readout device provides a readout value of each PSD upon application of the input wavefront to the holograph optical element, each readout value representing in the input wavefront the presence and magnitude of any of the particular aberrations defined by the reference waves.
    Type: Application
    Filed: December 13, 2006
    Publication date: June 19, 2008
    Inventors: Mark A. Stevens, Allen C. Layton
  • Publication number: 20040160597
    Abstract: An optical network may include a detector for detecting the power of each of a plurality of channels of a wavelength division multiplexed optical signal in one embodiment of the present invention. Each channel may be conveyed to an interface underneath a detector by way of a core formed in the substrate. The interface may include a trench with one side surface angled to form a reflector to reflect light upwardly to be detected by the detector. Other surfaces of said trench may also be reflective to reduce the cross talk between adjacent channels.
    Type: Application
    Filed: February 15, 2003
    Publication date: August 19, 2004
    Inventors: Tsung-Ein Tsai, Gabel Chong
  • Patent number: 6692129
    Abstract: The optical system includes a plurality of light modulators, one or more combining filters, and an optical relay system including a filter. Each light modulator modulates a corresponding incident light beam. The one or more combining filters superimpose the modulated light beams from each of the plurality of light modulators. The optical relay system filters the superimposed light and relays the filtered light to an image plane.
    Type: Grant
    Filed: September 5, 2002
    Date of Patent: February 17, 2004
    Assignee: Silicon Light Machines
    Inventors: Kenneth P. Gross, Paul Manhart, Richard A. Buchroeder
  • Publication number: 20040001196
    Abstract: A fluorescent image is obtained by emitting the light with a wavelength which excites a labelling fluorescent substance, a mask is created by a foreign matter area image extracted from an image of foreign matter adhering to the measurement object obtained by emitting light with a wavelength which does not excite the fluorescent substance, and logical multiplication of the mask and the fluorescent image is executed, thereby obtaining a fluorescent image that a foreign matter area is eliminated from the fluorescent image.
    Type: Application
    Filed: June 26, 2003
    Publication date: January 1, 2004
    Applicant: OLYMPUS OPTICAL CO., LTD.
    Inventors: Takami Shibazaki, Kaneyasu Okawa
  • Patent number: 6181416
    Abstract: An optical beam (3) passes through an illuminator (18), a semiconductor device (70), and an imager (20) to form a test object image (17) on a camera (16). Intensity variations in the object image (17) correspond to carrier density and temperature gradients inside the semiconductor device (70).
    Type: Grant
    Filed: April 14, 1999
    Date of Patent: January 30, 2001
    Assignee: OptoMetrix, Inc.
    Inventor: Robert Aaron Falk
  • Patent number: 5715047
    Abstract: A scanning mode sensor and method is provided for detection of flow inhomogeneities such as shock. The field of use of this invention is ground test control and engine control during supersonic flight.Prior art measuring techniques include interferometry, Schlieren, and shadowgraph techniques. These techniques, however, have problems with light dissipation.The present method and sensor utilizes a pencil beam of energy which is passed through a transparent aperture in a flow inlet in a time-sequential manner so as to alter the energy beam. The altered beam or its effects are processed and can be studied to reveal information about flow through the inlet which can in turn be used for engine control.
    Type: Grant
    Filed: July 8, 1996
    Date of Patent: February 3, 1998
    Assignee: The United States of America as represented by the Administrator of the National Aeronautics and Space Administration
    Inventor: Grigory Adamovsky
  • Patent number: 5583632
    Abstract: In an optical inspecting apparatus, first, a sample is illuminated with light. Then, an optical element causes light reflected from the sample or light transmitted through the sample to be focused, to thereby permit same to pass through an aperture stop arranged on a back focal plane or in its vicinity of the optical element. A telecenttic system converts the light having passed through the aperture stop into a parallel light. An image on the air formed by the telecentric system is viewed for inspection of the sample surface.
    Type: Grant
    Filed: July 6, 1994
    Date of Patent: December 10, 1996
    Assignee: New Creation Co., Ltd.
    Inventor: Kazumi Haga
  • Patent number: 5534995
    Abstract: A system and method are provided for recording density changes in a flow field surrounding a moving object. A mask having an aperture for regulating the passage of images therethrough is placed in front of an image recording medium. An optical system is placed in front of the mask. A transition having a light field-of-view and a dark field-of-view is located beyond the test object. The optical system focuses an image of the transition at the mask such that the aperture causes a band of light to be defined on the image recording medium. The optical system further focuses an image of the object through the aperture of the mask so that the image of the object appears on the image recording medium. Relative motion is minimized between the mask and the transition. Relative motion is also minimized between the image recording medium and the image of the object.
    Type: Grant
    Filed: February 14, 1995
    Date of Patent: July 9, 1996
    Assignee: The United States of America as represented by the Administrator of the National Aeronautics and Space Administration
    Inventor: Leonard M. Weinstein
  • Patent number: 5515158
    Abstract: A retroreflective type focusing schlieren system which permits the light source to be positioned on the optic side of the system. The system includes an extended light source, as opposed to a point source, located adjacent a beam splitter which projects light through the flow field onto a reflecting grating in the form of a grid which generates sheets of light that are directed back through the flow field and the beam splitter onto a primary lens behind which is located a cut-off grid having a grid pattern which corresponds to the grid pattern of the reflecting grating. The cut-off grid is adjustably positioned behind the primary lens and an image plane for imaging the turbulence is adjustably located behind the cut-off grid.
    Type: Grant
    Filed: February 1, 1994
    Date of Patent: May 7, 1996
    Assignee: The United States of America as Represented by the Administrator of the National Aeronautics and Space Administration
    Inventor: James T. Heineck
  • Patent number: 5153666
    Abstract: The sensitivity of refractive gradient detectors for detecting refractive index gradients in samples flowing through samples chambers is increased by detecting the gradients formed in the direction perpendicular to the direction of flow of the sample through the sample chamber and by detecting such gradients simultaneously intermediate the central axis and sides of the sample chamber on opposite sides of the central axis. A preferred detector uses two spaced, parallel probe light beams passing through the sample chamber between the central axis and sides of the chamber on opposite sides of the axis, with each beam preferably centered about half way between the axis and the respective side. A sensor detects relative movement of the probe beams caused by a refractive index gradient in the sample but preferably compensates for parallel movement of the parallel light beams caused by positional instability or mechanical movement of the light source.
    Type: Grant
    Filed: February 19, 1991
    Date of Patent: October 6, 1992
    Assignee: Anthony R. Torres
    Inventor: Janusz B. Pawliszyn
  • Patent number: 5142918
    Abstract: An apparatus to measure the bending length and bending rigidity of a piece of fabric comprising a generally planar surface upon which the plate of fabric is moved. The surface terminates at one end with an edge over which a leading end of the fabric passes. An optical device defines a plane extending downwardly from the surface edge at approximately 41.5 degrees. The optical device detects when the plane is intersected by the leading end of the fabric when, after a sufficient length of the piece of fabric has passed beyond the surface edge to cause bending of the fabric piece, the leading edge of the fabric intersects the plane.
    Type: Grant
    Filed: August 15, 1990
    Date of Patent: September 1, 1992
    Assignee: Commonwealth Scientific & Industrial Research Organization
    Inventors: Frank Scaysbrook, Nhan G. Ly
  • Patent number: 5072612
    Abstract: Light from a plurality of light emitting diodes is transmitted through optical cables (12) to a lens system. The lenses (56, 58) expand and collimate the light and project it in a sheet (16) across the supersonic inlet of an aircraft power plant perpendicular to incoming airflow. A normal shock bends a portion of the sheet of light (16). A linear array of a multiplicity of optical fiber ends collects discrete samples of light. The samples are processed and compared to a predetermined profile to determine the shock location.
    Type: Grant
    Filed: August 7, 1990
    Date of Patent: December 17, 1991
    Assignee: The Boeing Company
    Inventors: Donald G. Iverson, Jr., Troy D. Daiber
  • Patent number: 4993832
    Abstract: A differential, sequential detector, and method, for detecting refractive index gradients in a sample and for producing an output signal approximating a derivative of the refractive index gradient utilizes two closely spaced, parallel probe light beams passing through the sample with the beams separated along the direction of any expected gradient to be detected. A sensor is arranged to measure and produce an output signal proportional to the difference in movement of the two beams. The sensor is preferably arranged so that only complementing portions of each beam will fall on the sensing area of the sensor so that parallel movement of the beams will change equally the respective complementary portions sensed to maintain a constant output from the sensor, but movement of one beam relative to the other beam will produce a change in the sensor output proportional to the relative movement and approximating the derivative of refractive index gradient causing the relative beam movement.
    Type: Grant
    Filed: November 14, 1988
    Date of Patent: February 19, 1991
    Assignee: Anthony R. Torres
    Inventor: Janusz B. Pawliszyn
  • Patent number: 4979820
    Abstract: Two laser beams derived from a laser pass through a furnace and are superposed in a laser spot to produce interference fringes having the same pitch as that of a Ronchi grating printed on a retroreflecting screen. Minute fluctuations of the laser beams caused by sound waves from leaks result in intensity fluctuations of the laser spot when the laser fringes move past the fixed grating. A telescope and photocell arrangement detects the light variations to produce an electrical signal which is amplified and filtered to detect the sound of leaks. This non-contact laser Schlieren microphone is sensitive to sounds all along the path of the beams.
    Type: Grant
    Filed: April 24, 1989
    Date of Patent: December 25, 1990
    Inventors: Parthasarathy Shakkottai, Vijayaraghavan Alwar
  • Patent number: 4812039
    Abstract: A schlieren optical device using diode emitting monochromatic light as spot light source so as to have a compact and light-weight design, low calorific power, and low power consumption, and assure high reliability. In said optical device, imaging lens consists of a pair of lens groups arranged with an airspace reserved therebetween, knife edge consists of a light-shielding coating arranged on the surface of one of said lens groups and the other lens group is displaceable along the optical axis. Said optical device comprises a schlieren optical system and an optical system of a transmission type of microscope having optical axes perpendicularly intersecting with each other at the position of a sample, or a pair of schlieren optical systems and an optical system of a transmission type of microscope having optical axes perpendicularly intersecting with one another.
    Type: Grant
    Filed: October 16, 1987
    Date of Patent: March 14, 1989
    Assignee: Olympus Optical Co., Ltd.
    Inventors: Yoshihiro Shimada, Tadafumi Fujihara, Chikara Nagano, Katsuo Tsukamoto
  • Patent number: 4784494
    Abstract: Concentration gradients in samples to be evaluated are detected by measuring the deflection of a probe light beam passed through the sample using the principals of Shlieren optics. Specific chemical compounds in a sample can be detected and identified by supplying excitation energy to the sample where such energy is selected to be absorbed by the chemical compound to be specifically identified and not by other compounds in the sample. The absorption of the excitation energy by the absorbing compound produces a temperature gradient within the sample which causes deflection of the probe light beam and signals representative of such deflection may be separated from signals representative of deflections caused by other refractive index gradients present in the sample. A light emitting diode may be used to generate the probe light beam.
    Type: Grant
    Filed: December 31, 1986
    Date of Patent: November 15, 1988
    Assignee: Anthony R. Torres
    Inventor: Janusz B. Pawliszyn
  • Patent number: 4730924
    Abstract: Lens meter and method of measurement of progressive multifocal lens using the same which is able to set the amount of movement of the lens and to simply position a far- or near-distance refraction characteristics-measuring portion of a progressive multifocal lens. In accordance with the method the optical center of a lens is first found from measurement employing the lens and using the optical center as point of origin, the lens is moved by a distance up to the far-distance refraction characteristics measuring portion and the near-distance refraction characteristics measuring portion of the lens mentioned by the lens manufacturer, so as to effect alignment with the measurement optical axis of the lens meter, thereby measuring the refraction characteristics of each measuring portion.
    Type: Grant
    Filed: February 28, 1986
    Date of Patent: March 15, 1988
    Assignee: Tokyo, Kogaku, Kikai, Kabushiki, Kaisha
    Inventors: Henri Allard, Robert Drummond, Charles P. Villeneuve, Yukio Ikezawa
  • Patent number: 4681437
    Abstract: A system and method for monitoring the state of a crystal (C) which is suspended in a solution is disclosed which includes providing a light source (10) for emitting a beam (12) of light along an optical axis (X). A collimating lens is arranged along the optical axis for collimating the emitted beam to provide a first collimated light beam (16) consisting of parallel light rays. The solution and crystal are contained in a transparent container (18). By passing the first collimated light beam through the container, a number of the parallel light rays are deflected off of the surfaces of said crystal being monitored according to the refractive index gradient to provide a deflected beam (19) of deflected light rays. A focusing lens (22) is arranged along the optical axis for focusing the deflected rays (32, 34, 48, 50) towards a desired focal point (24a). A knife edge (24) is arranged in a predetermined orientation at the focal point; and a screen (26) is provided.
    Type: Grant
    Filed: February 28, 1985
    Date of Patent: July 21, 1987
    Assignee: The United States of America as represented by the Administrator of the National Aeronautics and Space Administration
    Inventors: Robert B. Owen, Mary H. Johnston
  • Patent number: 4654803
    Abstract: A method of measuring the velocity of a fluid by noninstrusive means comprises passing a pump laser beam pulse through the fluid wherein the fluid contains a constituent absorbing the wavelength of the laser so that a temperature gradient, and therefore an index of refraction gradient, occurs in the laser beam path; and a probe laser beam is passed transverse to the pump laser beam and is deflected by the heated portion of the fluid; measuring the beam deflection and calculating from that the fluid velocity. After the pump pulse the amount of deflection reaches a peak value and then decreases at a rate independent of the concentration of the absorbing constituent. Where the pump laser beam has a Gaussian spatial profile, the deflection signal decreases according to: exp-2(v+/a).sup.2, where v is the velocity; t is time; and a is a constant representing the pump laser beam radius.
    Type: Grant
    Filed: September 10, 1984
    Date of Patent: March 31, 1987
    Assignee: General Motors Corporation
    Inventor: Jeffrey A. Sell
  • Patent number: 4652120
    Abstract: A method of measuring the velocity of a fluid by nonintrusive means comprises passing a pulsed pump laser beam through the fluid wherein the fluid contains a constituent absorbing the wavelength of the laser so that a temperature gradient, and therefore an index of refraction gradient, occurs in the laser beam path; and a probe laser beam is passed transversely to the pump laser beam and is deflected by the heated portion of the fluid by an amount which is proportional to the concentration of the absorbing constituent and inversely proportional to the velocity of the fluid; measuring the beam deflection and calculating from that the fluid velocity, if the concentration of the absorbing constituent is known, or calculating the relative velocity if the concentration of the absorbing constituent is constant.
    Type: Grant
    Filed: September 10, 1984
    Date of Patent: March 24, 1987
    Assignee: General Motors Corporation
    Inventor: Jeffrey A. Sell
  • Patent number: 4547071
    Abstract: The present invention related to a method and a device for use in measuring the gradient of density in a fluid. The device is comprised of a laser for providing a columnar light beam and a photodetector axially aligned with the laser. The photodetector detects the displacement of the light beam caused by the gradient of refraction of the fluid. A unit is provided for converting the displacement into an indication of the gradient of refraction and thereby the gradient of the density of the fluid. For density gradients caused by concentration gradients, an additional unit is provided for converting the displacement into a measure of the quantity of substances in the fluid.
    Type: Grant
    Filed: June 30, 1982
    Date of Patent: October 15, 1985
    Assignee: Canadian Patents and Development Limited
    Inventor: Heshel Teitelbaum
  • Patent number: 4523097
    Abstract: A beam of light falling within the range of 180 to 3,000 nanometers is transmitted through a flow cell in an optical compartment of an absorbance detector after warm up of the equipment while the eluant flows through the flow cell from a chromatographic column. The column extends upwardly from the absorbance detector into an air chamber having a volume of approximately 0.25 cubic foot formed with acrylic walls. Air flows from the absorbance detector under the power of a fan at approximately 10 cubic feet per minute upwardly through an air duct having a cross section of approximately 1.5 square inches to the top where it connects with the air chamber, the speed of the motor being adjustable until temperature varies less than one degree Celsius between the flow cell and the lower 10 centimeters of the column. Under these conditions Schlieren noise from the flow cell due to flow-induced thermo-optical effects is reduced.
    Type: Grant
    Filed: August 31, 1983
    Date of Patent: June 11, 1985
    Assignee: ISCO, Inc.
    Inventor: Robert W. Allington
  • Patent number: 4391518
    Abstract: A dual laser optical system and method is disclosed for visualization of phenomena in transparent substances which induce refractive index gradients such as fluid flow and pressure and temperature gradients in fluids and gases. According to the invention two images 68 and 70 representing mutually perpendicular components of refractive index gradients may be viewed simultaneously on screen 66. Two lasers 10 and 12 having wave lengths in the visible range but separated by about 1000 angstroms are utilized to provide beams 14 and 20 which are collimated into a beam 32 containing components of the different wave lengths. The collimated beam 32 is passed through a test volume 33 of the transparent substance. The collimated beam is then separated into components of the different wave lengths and focused on to a pair of knife edges arranged mutually perpendicular to produce and project images 68 and 70 onto screen 66.
    Type: Grant
    Filed: January 12, 1981
    Date of Patent: July 5, 1983
    Assignee: The United States of America as represented by the Administrator of the National Aeronautics and Space Administration
    Inventors: Robert B. Owen, William K. Witherow
  • Patent number: 4188117
    Abstract: Leaks from a hollow fiber membrane module comprising a housing having one or more hollow fiber bundles positioned therein with at least one end of each bundle being sealed by a cementing layer includes the step of applying a pressurized gas to the external surfaces of the hollow fibers. The gas which is used must have a refractive index different from the refractive index of the ambient atmosphere. The atmospheric volume adjacent the sealed end of the module is optically monitored for refraction patterns caused by gas leaking through the sealed end into the volume. The optical system includes a light source and components for directing light from the source along an optical path including the monitored volume. Light which is passed through the monitored volume is directed to an optical display where the refraction patterns of the leaking gas will be visible. The method and apparatus permit leaks to be located without the use of liquids.
    Type: Grant
    Filed: April 27, 1978
    Date of Patent: February 12, 1980
    Assignee: Kuraray Co., Ltd.
    Inventors: Kazuhisa Yamauchi, Taku Tanaka, Syuji Kawai
  • Patent number: 4177482
    Abstract: Population and/or profile data of bodies contained within a transparent mass are obtained using a schlieren optical system in combination with a television camera, video analyzer, analog signal comparator and digital computer. The bodies, normally indistinguishable from the transparent mass by the unaided eye, are detected by the schlieren optical system and a television camera produces a video signal which is suitably processed, by the apparatus and method described, for introducing into a digital computer. The invention is especially useful as a means for quality control in various chemical operations.
    Type: Grant
    Filed: June 7, 1978
    Date of Patent: December 4, 1979
    Assignee: Eastman Kodak Company
    Inventor: James W. Henry
  • Patent number: 4139291
    Abstract: A system for use in Schlieren photography including a large grating, a viewing screen adjacently related to the large grating, a small grating disposed in spaced relation with the large grating, a transparent retainer for confining a transparent medium between the gratings, and optics for imaging the small grating on the large grating including a light source and optically aligned lens for projecting a beam of light along axes extending through the small grating and striking the large grating, subsequent to passing through the medium for thus forming on the screen a Schlieren image of striations resulting from distortions of light rays produced by the medium, and a camera for photographing the Schlieren image projected on the large screen.
    Type: Grant
    Filed: February 9, 1978
    Date of Patent: February 13, 1979
    Inventors: Robert A. Administrator of the National Aeronautics and Space Administration, with respect to an invention of Frosch, Shakkottai P. Parthasarathy
  • Patent number: 4131427
    Abstract: A means for detecting the presence of a solute in a flowing fluid stream is disclosed within. The schlieren patterns obtained when a solute present in a flowing fluid stream is directed into a reference fluid stream are utilized to scatter a portion of a light beam. The scattered light is detected and is related to the presence and amount of solute.
    Type: Grant
    Filed: February 13, 1978
    Date of Patent: December 26, 1978
    Inventor: Stewart Karp
  • Patent number: 4121247
    Abstract: Population and profile data of transparent bodies contained within a transparent mass are obtained using a schlieren optical system in combination with a television camera and receiver. The transparent bodies, normally indistinguishable from the transparent mass by the unaided eye, are detected by the schlieren optical system and then magnified and contrasted on the television receiver. The invention is especially useful as a means for quality control in various chemical operations.
    Type: Grant
    Filed: April 21, 1977
    Date of Patent: October 17, 1978
    Assignee: Eastman Kodak Company
    Inventor: James W. Henry
  • Patent number: 4099878
    Abstract: Apparatus and method employing line-of-sight wave propagation for measurement of various quantities such as velocity and refractivity structure of a transmission medium at selected locations remote from the measuring device.
    Type: Grant
    Filed: November 23, 1976
    Date of Patent: July 11, 1978
    Assignee: Argosystems, Inc.
    Inventor: Robert Wilton Lee