Patents by Inventor Steven Chu

Steven Chu 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).

  • Publication number: 20110220855
    Abstract: A dual action self-cleaning and self-decontaminating coating consisting of a superhydrophobic aspect capable of cleaning the surface by having water droplets moving along the surface remove contaminants and a photochemically active aspect capable of disinfecting the surface by producing hydroxyl radicals in the presence of UV radiation and moisture.
    Type: Application
    Filed: March 12, 2010
    Publication date: September 15, 2011
    Inventors: John D. Weir, Ronald G. Pirich, Dennis J. Leyble, Leonard G. Chorosinski, J. Donald Gardner, JR., Steven Chu
  • Publication number: 20110039094
    Abstract: Methods of bonding optical structures, bonded optical structures, silylated bonded optical structures, and the like, are disclosed.
    Type: Application
    Filed: November 8, 2007
    Publication date: February 17, 2011
    Applicant: Stanford University
    Inventors: Sanjeevi Sivasankar, Steven Chu
  • Publication number: 20100003498
    Abstract: UV resistant inorganic coatings which exhibit photochemical activity that destroys toxic biological and chemical agents are disclosed. The inorganic coatings include semiconductor metal oxide nanoparticles that are photo-chemically active dispersed in an inorganic binder. In one embodiment, anatase titanium dioxide nanoparticles are dispersed in a silicon dioxide or silicate binder. Applications may include spacecraft, aircraft, ships, military vehicles, high value equipment and buildings such as subway stations, hospitals, railroad stations and stadiums.
    Type: Application
    Filed: February 20, 2008
    Publication date: January 7, 2010
    Applicant: Northrop Grumman Corporation
    Inventors: John Douglas Weir, Ronald Gary Pirich, Donald DiMarzio, Dennis J. Leyble, Steven Chu
  • Patent number: 7462809
    Abstract: An improved system for visual inspection of substrates coated with paints and polymers is disclosed. Painted substrates can be inspected for environmental and physical damage such as corrosion and cracks without removing the paint. The present invention provides the ability to maximize paint thickness penetration. This is accomplished with a spectral bandpass filter that rejects reflected light from the coating opaque bands, while allowing light in the paint window to pass to an IR detector such as an IR camera focal plane. The narrow bandpass range enhances the ability for IR imaging to see through thicker paint layers and improves the contrast over standard commercial IR mid-wave cameras. The bandpass may be adjusted to coincide with the full spectral window of the paint, consistent with the ability of the imaging focal plane to detect light in the spectral region.
    Type: Grant
    Filed: August 18, 2006
    Date of Patent: December 9, 2008
    Assignee: Northrop Grumman Corporation
    Inventors: Donald DiMarzio, John Douglas Weir, Steven Chu, Nils Jakob Fonneland, Dennis John Leyble
  • Patent number: 7164146
    Abstract: A system is disclosed which utilizes the substantially steady-state temperature of a coated object, in conjunction with an optical detection system, to selectively view defects and features of the object below the coating without the necessity of transient heating or IR illumination and reflectance imaging. The optical detector, such as an IR camera, may be tailored for the wavelengths at which the coating material is substantially transparent, thereby maximizing the viewing clarity of the defects and features under the coating, and distinguishing them from any spurious features on the top surface of the coating. The present system enables the inspection of small or large areas in real time, without requiring complex image acquisition, storage and image processing equipment and software.
    Type: Grant
    Filed: October 22, 2004
    Date of Patent: January 16, 2007
    Assignee: Northrop Grumman Corporation
    Inventors: John Douglas Weir, Donald DiMarzio, Steven Chu, Robert P. Silberstein
  • Publication number: 20060289766
    Abstract: An improved system for visual inspection of substrates coated with paints and polymers is disclosed. Painted substrates can be inspected for environmental and physical damage such as corrosion and cracks without removing the paint. The present invention provides the ability to maximize paint thickness penetration. This is accomplished with a spectral bandpass filter that rejects reflected light from the coating opaque bands, while allowing light in the paint window to pass to an IR detector such as an IR camera focal plane. The narrow bandpass range enhances the ability for IR imaging to see through thicker paint layers and improves the contrast over standard commercial IR mid-wave cameras. The bandpass may be adjusted to coincide with the full spectral window of the paint, consistent with the ability of the imaging focal plane to detect light in the spectral region.
    Type: Application
    Filed: August 18, 2006
    Publication date: December 28, 2006
    Applicant: Northrop Grumman Corporation
    Inventors: Donald DiMarzio, John Weir, Steven Chu, Nils Fonneland, Dennis Leyble
  • Publication number: 20060086912
    Abstract: A system is disclosed which utilizes the substantially steady-state temperature of a coated object, in conjunction with an optical detection system, to selectively view defects and features of the object below the coating without the necessity of transient heating or IR illumination and reflectance imaging. The optical detector, such as an IR camera, may be tailored for the wavelengths at which the coating material is substantially transparent, thereby maximizing the viewing clarity of the defects and features under the coating, and distinguishing them from any spurious features on the top surface of the coating. The present system enables the inspection of small or large areas in real time, without requiring complex image acquisition, storage and image processing equipment and software.
    Type: Application
    Filed: October 22, 2004
    Publication date: April 27, 2006
    Applicant: Northrop Grumman Corporation
    Inventors: John Weir, Donald DiMarzio, Steven Chu, Robert Silberstein
  • Patent number: 7013739
    Abstract: A device for confining an object to a region proximate to a fluid flow stagnation point includes one or more inlets for carrying the fluid into the region, one or more outlets for carrying the fluid out of the region, and a controller, in fluidic communication with the inlets and outlets, for adjusting the motion of the fluid to produce a stagnation point in the region, thereby confining the object to the region. Applications include, for example, prolonged observation of the object, manipulation of the object, etc. The device optionally may employ a feedback control mechanism, a sensing apparatus (e.g., for imaging), and a storage medium for storing, and a computer for analyzing and manipulating, data acquired from observing the object. The invention further provides methods of using such a device and system in a number of fields, including biology, chemistry, physics, material science, and medical science.
    Type: Grant
    Filed: May 7, 2004
    Date of Patent: March 21, 2006
    Assignee: The Board of Trustees of the Leland Stanford Junior University
    Inventors: Charles M. Schroeder, Eric S. G. Shaqfeh, Hazen P. Babcock, Steven Chu
  • Publication number: 20060005634
    Abstract: A device for confining an object to a region proximate to a fluid flow stagnation point includes one or more inlets for carrying the fluid into the region, one or more outlets for carrying the fluid out of the region, and a controller, in fluidic communication with the inlets and outlets, for adjusting the motion of the fluid to produce a stagnation point in the region, thereby confining the object to the region. Applications include, for example, prolonged observation of the object, manipulation of the object, etc. The device optionally may employ a feedback control mechanism, a sensing apparatus (e.g., for imaging), and a storage medium for storing, and a computer for analyzing and manipulating, data acquired from observing the object. The invention further provides methods of using such a device and system in a number of fields, including biology, chemistry, physics, material science, and medical science.
    Type: Application
    Filed: May 7, 2004
    Publication date: January 12, 2006
    Inventors: Charles Schroeder, Eric Shaqfeh, Hazen Babcock, Steven Chu
  • Patent number: 6684645
    Abstract: The invention relates to a method and apparatus for cooling multilevel entities such as atoms, ions or molecules as well as entities with no apparent internal structure. Cooling is achieved by coherent scattering, where the frequency of the emitted radiation exceeds the frequency of the illumination radiation. Such coherent scattering is achieved by placing the entities in a resonator containing in which the cavity length and mirror coating are selected to support a resonant radiation. The entities are illuminated with an illumination radiation whose energy is lower than that of the resonant radiation supported by the resonator by a certain detuning energy selected such that coherent scattering of resonant radiation from the entities at a higher frequency than that of the illumination radiation is promoted by the resonator. As a result of the coherent scattering energy is carried away from the entities and they are cooled.
    Type: Grant
    Filed: April 4, 2002
    Date of Patent: February 3, 2004
    Assignee: The Board of Trustees of the Leland Stamford Junior University
    Inventors: Steven Chu, Vladan Vuletic
  • Publication number: 20030136131
    Abstract: The invention relates to a method and apparatus for cooling multilevel entities such as atoms, ions or molecules as well as entities with no apparent internal structure. Cooling is achieved by coherent scattering, where the frequency of the emitted radiation exceeds the frequency of the illumination radiation. Such coherent scattering is achieved by placing the entities in a resonator containing in which the cavity length and mirror coating are selected to support a resonant radiation. The entities are illuminated with an illumination radiation whose energy is lower than that of the resonant radiation supported by the resonator by a certain detuning energy selected such that coherent scattering of resonant radiation from the entities at a higher frequency than that of the illumination radiation is promoted by the resonator. As a result of the coherent scattering energy is carried away from the entities and they are cooled.
    Type: Application
    Filed: April 4, 2002
    Publication date: July 24, 2003
    Inventors: Steven Chu, Vladan Vuletic
  • Patent number: 5528028
    Abstract: Beams of laser light trap and cool cesium atoms in a small vapor cell and put the atoms in a particular quantum mechanical state. The lasers are then configured so as to launch the atoms upward by shifting the frequencies of the vertically propagating lasers. The atoms pass through a microwave waveguide during both their ascent and descent. The microwave field is applied briefly each time the atoms are in the center of the waveguide so that the microwaves excite the cesium "clock" transition. Once the atoms have fallen back to where they started, the laser fields are turned on in a particular sequence. The fraction of the atoms that make a quantum mechanical transition is measured by observing the laser light scattered by the atoms. That signal indicates how close the microwave frequency is to the atomic transition. The laser cooling reduces the relative motion of the atoms so that the atoms can be observed longer. The resulting atomic resonance measured is much narrower.
    Type: Grant
    Filed: October 20, 1994
    Date of Patent: June 18, 1996
    Inventors: Steven Chu, Carl Weiman, William Swann
  • Patent number: 5512745
    Abstract: By providing a focal region of light onto a particle, a laser-based light source can provide enough radiation pressure to position the particle at any desired location in space. In one application, the particle can be a micrometer-sized bead, called a handle, attached to a sample. When the sample under examination, such as an actin filament, interacts with other molecules, such as myosin, the forces generated may displace the sample, and thus the handle, out of its original position. To correct for the off-target position (or in other words, to increase the stiffness of the handle), a feedback loop that utilizes a quadrant photodiode detector and a focal region location means such as an acousto-optic modulator or galvanometer mirror is incorporated in the optical trap system. Use of two other light sources for brightfield illumination and epifluorescence allows the simultaneous viewing of the sample in real time. In other embodiments, the optical trap system can trap and manipulate particles.
    Type: Grant
    Filed: March 9, 1994
    Date of Patent: April 30, 1996
    Assignee: Board of Trustees of the Leland Stanford Jr. University
    Inventors: Jeffrey Finer, Robert Simmons, James A. Spudich, Steven Chu
  • Patent number: 5338930
    Abstract: Beams of laser light trap and cool cesium atoms in a small vapor cell and put the atoms in a particular quantum mechanical state. The lasers are then configured so as to launch the atoms upward by shifting the frequencies of the vertically propagating lasers. The atoms pass through a microwave waveguide during both their ascent and descent. The microwave field is applied briefly each time the atoms are in the center of the waveguide so that the microwaves excite the cesium "clock" transition. Once the atoms have fallen back to where they started, the laser fields are turned on in a particular sequence. The fraction of the atoms that make a quantum mechanical transition is measured by observing the laser light scattered by the atoms. That signal indicates how close the microwave frequency is to the atomic transition. The laser cooling reduces the relative motion of the atoms so that the atoms can be observed longer. The resulting atomic resonance measured is much narrower.
    Type: Grant
    Filed: November 24, 1992
    Date of Patent: August 16, 1994
    Assignee: Research Corporation Technologies
    Inventors: Steven Chu, Carl Weiman, William Swann
  • Patent number: 5274231
    Abstract: Quantum objects, such as atoms, ions, and molecules, are controllably moved by stimulating selected non-radiative energy levels within a quantum structure in accordance with the principles of stimulated Raman transitions. The movement is effected by timed excitation of individual quantum objects with preselected quantities ("pulses") of electromagnetic energy of at least two different frequencies which together are in resonance with a natural resonance (i.e., a stimulated Raman transition) of preferably metastable energy levels within the quantum object to cause a controlled change in momentum of the quantum object. Specific embodiments employ amplitude modulated collinear beams or multiple beams along different beam paths or collinear beams which are phase coherent but from independent laser sources.
    Type: Grant
    Filed: April 14, 1992
    Date of Patent: December 28, 1993
    Assignee: Board of Trustees, Leland Stanford Jr. University
    Inventors: Steven Chu, Mark A. Kasevich
  • Patent number: 5274232
    Abstract: According to the invention, quantum objects, such as atoms, ions, and molecules, are controllably moved by stimulating selected non-radiative energy levels within a quantum structure in accordance with the principles of stimulated Raman transitions. The movement is effected by timed excitation of individual quantum objects with preselected quantities ("pulses") of electromagnetic energy of at least two different frequencies which together are in resonance with a natural resonance (i.e., a stimulated Raman transition) of preferably metastable energy levels within the quantum object to cause a controlled change in momentum of the quantum object. In alternative embodiments, single-pulse excitation or multiple-pulse sequence excitation with stimulated Raman transitions produce a controlled change in momentum of individual quantum objects according to the invention. A controlled distribution of velocities of an ensemble of quantum objects may be effected in accordance with the invention.
    Type: Grant
    Filed: April 14, 1992
    Date of Patent: December 28, 1993
    Assignee: Board of Trustees, Leland Stanford Jr. University
    Inventors: Steven Chu, Mark A. Kasevich
  • Patent number: 5079169
    Abstract: Method and apparatus for manipulating a microscopic particle by single-beam gradient optical trapping, using an optical beam whose trapping force is substantially independent of position within a view field. The apparatus may be used to extend a polymer filament, and to fix the extended filament at a selected stretching force. When applied to nucleic acid filament, the method may be employed for genomic DNA mapping of filaments up to several megabasepairs in size. The method may also be used for studying the interaction of enzymes or ribosomes with extended DNA in real time.
    Type: Grant
    Filed: May 22, 1990
    Date of Patent: January 7, 1992
    Assignee: The Regents of the Stanford Leland Junior University
    Inventors: Steven Chu, Stephen J. Kron
  • Patent number: 4742224
    Abstract: An ion energy filter of the type useful in connection with secondary ion mass spectrometry is disclosed. The filter is composed of a stack of 20 thin metal plates, each plate being insulated from the others and having a centrally located hole with a unique radius. A metallic hemisphere is mounted on a base plate, and the 20 thin metal plates are attached to the base plate such that the plate with the smallest central hole is adjacent to the base plate and the radii of the holes in subsequent plates increase with increasing distance from the base plate. The relative potential of each plate is determined by a series string of 20 resistors with each plate being connected to a different junction in the series string. The radii of the centrally located holes are selected such that the voltage on each plate is inversely proportional to the radius of its centrally located hole.
    Type: Grant
    Filed: December 22, 1986
    Date of Patent: May 3, 1988
    Assignee: American Telephone and Telegraph Company AT&T Bell Laboratories
    Inventors: Steven Chu, Aly Dayem, Eric H. Westerwick