Patents by Inventor Demetri Psaltis

Demetri Psaltis 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).

  • Patent number: 7768654
    Abstract: A differential interference contrast (DIC) determination device and method utilizes an illumination source, a layer having a pair of two apertures that receive illumination from the illumination source, and a photodetector to receive Young's interference from the illumination passing through the pair of two apertures. In addition, a surface plasmon assisted optofluidic microscope and method utilize an illumination source, a fluid channel having a layer with at least one aperture as a surface, and a photodetector that receives a signal based on the illumination passing through the aperture. The layer is corrugated (e.g., via fabrication) and parameters of the corrugation optimize the signal received on the photodetector.
    Type: Grant
    Filed: May 2, 2007
    Date of Patent: August 3, 2010
    Assignee: California Institute of Technology
    Inventors: Xiquan Cui, Xin Heng, Changhuei Yang, Axel Scherer, Demetri Psaltis
  • Patent number: 7751048
    Abstract: Optofluidic microscope devices and methods of using optofluidic microscope devices, where each optofluidic device comprises a body with a fluid channel having a surface, light transmissive regions in the body wherein the light transmissive regions have different dimensions, an illumination source adapted to provide illumination through the light transmissive regions, and an optical detector adapted to receive light from the illumination source through the light transmissive regions. The light transmissive regions and optical detector can be used to image an object flowing through the fluid channel.
    Type: Grant
    Filed: March 14, 2007
    Date of Patent: July 6, 2010
    Assignee: California Institute of Technology
    Inventors: Changhuei Yang, Demetri Psaltis
  • Patent number: 7542639
    Abstract: In the present invention, a volume holographic optical element is used as a pump coupler. The holographic coupler allows at least one pump wavelength to be coupled into the laser medium. The direction of the pump beam onto the coupler is not co-linear with the direction of the signal beam out of the coupler. The invention further provides the coupling of more than one pump wavelengths using a single holographic coupler element while maintaining the high isolation between pump and signal beam. The invention further provides a narrow-band reflection grating of various efficiencies for the signal beam (as part of the laser cavity).
    Type: Grant
    Filed: March 29, 2005
    Date of Patent: June 2, 2009
    Assignee: ONDAX, Inc
    Inventors: Christophe Moser, Karsten Buse, Demetri Psaltis
  • Publication number: 20090067018
    Abstract: A harmonic holography (H2) technique and system that combines holography and nonlinear optics that enables holographic recording of 3D images with femtosecond framing time are provided. The H2 technique records holograms with second harmonic (SH) signals scattered off specialized nanocrystals that are functionalized to label specific protein or other biomolecules in a living organism. The capability of generating second harmonic radiations is specific to materials with noncentrosymmetric crystalline structures only, and ?(2) vanishes for all other types of materials. Therefore, a sharp contrast is formed when particles of noncentrosymmetric structures are dispersed in a medium of other species, pumped at a fundamental frequency, and imaged at the second harmonic frequency. The new scheme described herein provides a sound basis for a new type of contrast microscopy with enormous potential in molecular biomedical imaging.
    Type: Application
    Filed: November 21, 2007
    Publication date: March 12, 2009
    Inventors: Ye Pu, Demetri Psaltis
  • Patent number: 7483190
    Abstract: The present invention provides a multi-channel tunable filter and methods for making such a filter. In one embodiment, the filter comprises a bank of gratings or a continuously varying filter frequency imprinted into a filter material, such as Lithium Niobate or glass or polymer. An optical read-head comprising a pair of lenses is configured to pass light from within an optical fiber carrying multiple wavelengths through an appropriate grating to extract or drop a specific wavelength. To ensure continuous data transmission, the filter is tuned to a wavelength by configuring the read-head to move in a hitless manner. In one embodiment, the gratings are recorded by the interference of two beams. A first plane wave reflects off a first mirror stack and a second plane wave reflects off a second mirror stack. In another embodiment, the gratings are recorded by a phase masking method.
    Type: Grant
    Filed: March 8, 2006
    Date of Patent: January 27, 2009
    Assignee: Ondax, Inc.
    Inventors: Demetri Psaltis, Christophe Moser, Greg Steckman, Karsten Buse, Ingo Nee, Joerg Hukriede
  • Publication number: 20080245430
    Abstract: A method of microfluidic control via localized heating includes providing a microchannel structure with a base region that is partially filled with a volume of liquid being separated from a gas by a liquid-gas interface region. The base region includes one or more physical structures. The method further includes supplying energy input to a portion of the one or more physical structures within the volume of liquid in a vicinity of the liquid-gas interface region to cause localized heating of the portion of the one or more physical structures. The method also includes transferring heat from the portion of the one or more physical structures to surrounding liquid in the vicinity of the liquid-gas interface region and generating an interphase mass transport at the liquid-gas interface region or across a gas bubble while the volume of liquid and the gas remain to be substantially at ambient temperature.
    Type: Application
    Filed: January 25, 2008
    Publication date: October 9, 2008
    Applicant: California Institute of Technology
    Inventors: James Adleman, David A. Boyd, David G. Goodwin, Demetri Psaltis
  • Publication number: 20080159351
    Abstract: The invention relates to a microfluidic dye laser including a pump light source configured to provide light having a pump light wavelength. The microfluidic dye laser also includes an elastomer substantially optically transparent at the pump light wavelength and at a microfluidic dye laser wavelength. A microfluidic channel configured to accept a fluidic dye is defined in the elastomer. An optical grating is formed in a single mode 3D waveguide in the microfluidic channel in order to provide a single mode microfluidic dye laser light as output in response to illumination with light from the pump light source. In another aspect, the invention features a method of tuning a wavelength of a microfluidic dye laser light by mechanically deforming the elastomeric laser chip to change the grating period in the optical cavity.
    Type: Application
    Filed: August 9, 2007
    Publication date: July 3, 2008
    Applicant: California Institute of Technology
    Inventors: Zhenyu Li, Demetri Psaltis, Axel Scherer, Zhaoyu Zhang
  • Patent number: 7367505
    Abstract: The invention combines fluorescent QDs and methods to dispense and detect them efficiently in a compact volume for a range of optical tagging applications. Micro-fluidic devices are used for mixing water-soluble fluorescent QDs in aqueous solutions to create a multi color fluorescent nano-optical tag, and gratings are used for spreading the spectral components of the fluorescent signal leading to an improvement in optical data storage capacity over prior art methods. The spectral signature of the tag is detected by a compact read-out head with a grating spectrometer. One way is to dispense the tag within the pits of a DVD or CD using an ink-jet nozzle and exciting them by a large range of wavelengths each shorter that the emission peak. The filters have a high immunity to prolonged exposure to high temperatures, and up to 41 infrared filters can be holographically recorded by spatial multiplexing of the substrate.
    Type: Grant
    Filed: June 9, 2004
    Date of Patent: May 6, 2008
    Assignee: California Institute of Technology
    Inventors: Demetri Psaltis, Christophe Moser
  • Patent number: 7346248
    Abstract: Systems and methods for manipulating light with tunable ferroelectric photonic devices. Devices having tunable properties that exhibit photonic bandgap behavior are fabricated from ferroelectric materials. Apparatus is provided to apply tuning signals to the ferroelectric material using one or more of electric fields, mechanical forces, optical fields, and thermal fields. Control circuitry is provided to generate the control signals needed to apply the tuning signals. Input and output ports are provided to allow input signals to be received and to provide output signals. In some cases, a feedback loop is provided to use a portion of the output signal as a diagnostic signal for control of the operation of the device within an acceptable range. It is expected that ferroelectric photonic devices operating according to principles of the invention will be useful for a wide variety of applications, including optical switching, optical modulation, optical computing, and performing logic optically.
    Type: Grant
    Filed: August 1, 2006
    Date of Patent: March 18, 2008
    Assignee: California Institute of Technology
    Inventors: Harry A. Atwater, Kaushik Bhattacharya, Kaushik Dayal, Matthew Dicken, Demetri Psaltis, Axel Scherer, Guruswami Ravichandran
  • Publication number: 20080019648
    Abstract: Systems and methods for manipulating light with tunable ferroelectric photonic devices. Devices having tunable properties that exhibit photonic bandgap behavior are fabricated from ferroelectric materials. Apparatus is provided to apply tuning signals to the ferroelectric material using one or more of electric fields, mechanical forces, optical fields, and thermal fields. Control circuitry is provided to generate the control signals needed to apply the tuning signals. Input and output ports are provided to allow input signals to be received and to provide output signals. In some cases, a feedback loop is provided to use a portion of the output signal as a diagnostic signal for control of the operation of the device within an acceptable range. It is expected that ferroelectric photonic devices operating according to principles of the invention will be useful for a wide variety of applications, including optical switching, optical modulation, optical computing, and performing logic optically.
    Type: Application
    Filed: August 1, 2006
    Publication date: January 24, 2008
    Applicant: California Institute of Technology
    Inventors: Harry Atwater, Kaushik Bhattacharya, Kaushik Dayal, Matthew Dicken, Demetri Psaltis, Axel Scherer, Guruswami Ravichandran
  • Publication number: 20070258096
    Abstract: A differential interference contrast (DIC) determination device and method utilizes an illumination source, a layer having a pair of two apertures that receive illumination from the illumination source, and a photodetector to receive Young's interference from the illumination passing through the pair of two apertures. In addition, a surface plasmon assisted optofluidic microscope and method utilize an illumination source, a fluid channel having a layer with at least one aperture as a surface, and a photodetector that receives a signal based on the illumination passing through the aperture. The layer is corrugated (e.g., via fabrication) and parameters of the corrugation optimize the signal received on the photodetector.
    Type: Application
    Filed: May 2, 2007
    Publication date: November 8, 2007
    Applicant: CALIFORNIA INSTITUTE OF TECNOLOGY
    Inventors: Xiquan Cui, Xin Heng, Changhuei Yang, Axel Scherer, Demetri Psaltis
  • Publication number: 20070207061
    Abstract: An optofluidic microscope device is disclosed. The device includes a fluid channel having a surface and an object such as a bacterium or virus may flow through the fluid channel. Light transmissive regions of different sizes may be used to image the object.
    Type: Application
    Filed: March 14, 2007
    Publication date: September 6, 2007
    Applicant: California Institute of Technology
    Inventors: Changhuei Yang, Demetri Psaltis
  • Publication number: 20070148045
    Abstract: The invention provides a particle detection system. In one embodiment, the system detects live bacteria by aligning the bacteria in a test specimen with an electric field, illuminating the test specimen, and detecting the optical scattering. This invention uses no biochemical markers and can be applied in a Point-of-Care setting.
    Type: Application
    Filed: October 12, 2006
    Publication date: June 28, 2007
    Applicant: California Institute of Technology
    Inventors: Allen Pu, Demetri Psaltis
  • Publication number: 20070002413
    Abstract: A light conductive controlled shape droplet display device of the invention includes a light source. A light conductive substrate receives and conducts light from the light source. A cover disposed relative to the substrate, conducts light received from the substrate out and away from the display device. Pixels in the display are defined by fluid droplets in optical communication with the substrate and the cover. Hydrophobic layers associated with the substrate and the cover control the shape of the fluid droplet in conjunction with properties of the fluid droplet. Persistent displays are possible, as are displays that require periodic refresh to maintain the display. Electrodes modulate the amount of light conducted by the fluid droplets from the substrate into the cover. In preferred embodiments, each pixel includes sub-pixels formed by different primary colored fluid droplets.
    Type: Application
    Filed: June 12, 2006
    Publication date: January 4, 2007
    Inventors: Demetri Psaltis, Allen Pu
  • Patent number: 7158228
    Abstract: A holographic imaging spectrometer, apparatus, and/or method enables the projection of a two-dimensional (2D) slice (having spectral information) of a four-dimensional (4D) probing object. A 4D probing source object is illuminated to emit an optical field. A holographic element having one or more recorded holograms receives and diffracts the optical field into a diffracted plane beam having spectral information. Collector optics (e.g., an imaging lens) focuses the diffracted plane beam having spectral information to a 2D slice (having spectral information) of the 4D probing source object. The focused 2D slice having spectral information is projected onto a 2D detector array surface. In addition, the holographic element may have multiple multiplexed holograms that are arranged to diffract light from the corresponding slice of the 4D probing source object to a non-overlapping section of the detector.
    Type: Grant
    Filed: July 25, 2003
    Date of Patent: January 2, 2007
    Assignees: California Institute of Technology, Massachusetts Institute of Technology
    Inventors: Demetri Psaltis, Wenhai Liu, Jose Mumbru, George Barbastathis
  • Patent number: 7136206
    Abstract: The present invention provides a multi-channel tunable filter and methods for making such a filter. In one embodiment, the filter comprises a bank of gratings imprinted into a filter material, such as Lithium Niobate. In another embodiment, the filter comprises a bank of gratings imprinted on a thin-film filter. An optical read-head comprising a pair of lenses is configured to pass light from within an optical fiber carrying multiple wavelengths through an appropriate grating to extract or drop a specific wavelength. To ensure continuous data transmission, the filter is tuned to a wavelength by configuring the read-head to move in a hitless manner. In one embodiment, the gratings are recorded by the interference of two beams. A first plane wave reflects off a first mirror stack and a second plane wave reflects off a second mirror stack. In another embodiment, the gratings are recorded by a phase masking method.
    Type: Grant
    Filed: December 3, 2004
    Date of Patent: November 14, 2006
    Assignee: California Institute of Technology
    Inventors: Demetri Psaltis, Christophe Moser, Greg Steckman, Karsten Buse, Ingo Nee, Joerg Hukriede
  • Patent number: 7102803
    Abstract: A temperature compensated apparatus for filtering light is comprised of a holographically recorded grating defined in a photosensitive layer for providing optical filtration for light incident on the grating with a predetermined angle of incidence, and an angulation means responsive to temperature for tilting the grating relative to the angle of incidence of the light as a function of temperature of the grating so that changes in the filtration by the grating compensate for changes in temperature of the grating to maintain effective filtration of the light approximately constant.
    Type: Grant
    Filed: November 18, 2003
    Date of Patent: September 5, 2006
    Assignee: California Institute of Technology
    Inventors: Demetri Psaltis, George Panotopoulos, Hung-Te Hsieh
  • Publication number: 20060156241
    Abstract: The present invention provides a multi-channel tunable filter and methods for making such a filter. In one embodiment, the filter comprises a bank of gratings or a continuously varying filter frequency imprinted into a filter material, such as Lithium Niobate or glass or polymer. An optical read-head comprising a pair of lenses is configured to pass light from within an optical fiber carrying multiple wavelengths through an appropriate grating to extract or drop a specific wavelength. To ensure continuous data transmission, the filter is tuned to a wavelength by configuring the read-head to move in a hitless manner. In one embodiment, the gratings are recorded by the interference of two beams. A first plane wave reflects off a first mirror stack and a second plane wave reflects off a second mirror stack. In another embodiment, the gratings are recorded by a phase masking method.
    Type: Application
    Filed: March 8, 2006
    Publication date: July 13, 2006
    Inventors: Demetri Psaltis, Christophe Moser, Greg Steckman, Karsten Buse, Ingo Nee, Joerg Hukriede
  • Patent number: 6987907
    Abstract: The present invention is a method and apparatus for a rotating, tunable, holographic drop filter connected to a fiber optic source. The filter uses a quasi phase-conjugate optical system for a drop-channel fiber coupling and WDM channels which are introduced to the system. The light from these channels is collimated and passed through a volume phase holographic material so that only one WDM channel is diffracted and the rest pass through the holographic material unaffected. A quasi phase-conjugate diffracted beam is generated by the optical system to reflect the diffracted channel back towards the holographic material. The reflected light is Bragg matched to the holographic material so that it is re-diffracted along a path identical to the original incident light beam. A free-space circulator may be used to direct the diffracted beam to a fiber optic collimator, which is different from the fiber optic collimator of the incident light beam.
    Type: Grant
    Filed: December 4, 2001
    Date of Patent: January 17, 2006
    Assignee: California Institute of Technology
    Inventors: Demetri Psaltis, Christophe Moser, Greg Steckman, Karsten Buse, Ingo Nee, Joerg Hukriede, Joseph W. Goodman
  • Publication number: 20050271548
    Abstract: An optofluidic microscope device is disclosed. The device includes a fluid channel having a surface and an object such as a bacterium or virus may flow through the fluid channel. Light imaging elements in the bottom of the fluid channel may be used to image the object.
    Type: Application
    Filed: May 9, 2005
    Publication date: December 8, 2005
    Applicant: California Institute of Technology, Office of Technology Transfer
    Inventors: Changhuei Yang, Demetri Psaltis