Changing Bulk Optical Parameter Patents (Class 359/240)
  • Patent number: 6791732
    Abstract: Optical modulators are provided. A representative optical modulator includes an optical medium that is adapted to propagate optical signals. An array of lattice sites are arranged in the optical medium, with at least some of the lattice sites exhibiting lower refractive indexes than the refractive index of the optical medium. Preferably, a first of the lattice sites incorporates a first optical component that is moveable relative to the optical medium. By moving the first optical component relative to the optical medium, a propagation characteristic of the optical medium can be altered. Optical systems, methods and other optical modulators also are provided.
    Type: Grant
    Filed: June 20, 2002
    Date of Patent: September 14, 2004
    Assignee: Agilent Technologies, Inc.
    Inventor: Jonathan Simon
  • Patent number: 6781733
    Abstract: An optical film comprising microlenses, a light shield layer and a light diffusion layer, wherein, for example, the light transmittance passing through the light shield layer is modulated depending on changed concentrations of silver or a compound containing silver dispersed in gelatin in the light shield layer, has wide angle of field properties and high contrast properties, and can be applied to image display apparatuses such as a liquid crystal display to improve angle of field properties, contrast properties and to prevent image deterioration against outer light.
    Type: Grant
    Filed: October 17, 2000
    Date of Patent: August 24, 2004
    Assignees: Hitachi, Ltd., Nitto Denko Corporation
    Inventor: Yasuo Hira
  • Patent number: 6777718
    Abstract: A semiconductor optical device includes a substrate, an optical waveguide layer on the substrate and having well and barrier layers. The semiconductor optical device also includes an optical absorbing layer on the substrate and adjacent to the optical waveguide layer so that incident light having an incident wavelength &lgr;LD is guided into the optical absorbing layer. Each of the well layers has a wavelength &lgr;g corresponding to the band gap of the well layers and that is larger than the incident wavelength &lgr;LD. Also, the band gap energy between base levels of a conduction band and a valence band of the optical waveguide layer is larger than the energy of the incident light having the incident wavelength &lgr;LD.
    Type: Grant
    Filed: February 4, 2003
    Date of Patent: August 17, 2004
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventor: Kazuhisa Takagi
  • Publication number: 20040130769
    Abstract: A conformal retro-modulator optical apparatus. The apparatus includes an array of multiple quantum well devices disposed in a thin array. A plastic support element is bonded to the thin array, the plastic support element having a thickness greater that of the thin array. The plastic support element is preferably plastic at elevated temperatures above room temperature, thereby allowing the plastic support element and the thin array of multiple well device disposed therein to conform to a predetermined shape, yet being rigid at room temperature.
    Type: Application
    Filed: October 20, 2003
    Publication date: July 8, 2004
    Inventors: Keyvan Sayyah, David M. Pepper, Peter D. Brewer, Anson Au
  • Publication number: 20040125429
    Abstract: Provided is an optical modulator for modulating light comprising: a superlattice structure having a plurality of interleaved narrow and wide bandgap semiconductor layers, wherein wave functions of energy states of electrons and holes in different narrow bandgap layers are coupled; and a power supply that applies voltage to the superlattice structure between a first non-zero voltage and a second non-zero voltage to modulate the light.
    Type: Application
    Filed: January 15, 2004
    Publication date: July 1, 2004
    Inventors: Amnon Manassen, Ori J. Braun, Giora Yahav
  • Publication number: 20040114207
    Abstract: The present invention provides an optoelectronic device, a method of manufacturing thereof, and an optical communications system including the same. The optoelectronic device includes an optical substrate coupled to a submount and including an optical device, and a signal and a ground conductor coupled to the submount, wherein the signal and ground conductors have a direction of signal propagation associated therewith, and wherein related transitions of the signal and ground conductors between the submount and the optical substrate are separated along the direction by a predetermined distance.
    Type: Application
    Filed: December 9, 2003
    Publication date: June 17, 2004
    Applicant: TriQuint Technology Holding Co.
    Inventors: Joseph M. Freund, John M. Geary
  • Patent number: 6747776
    Abstract: A semiconductor optical modulator having an electroabsorptive layer and a pair of modulating voltage electrodes also has a direct-current voltage electrode, from which an unmodulated electric field can be applied to the electroabsorptive layer to adjust the output optical power level. The output optical power level can thus be adjusted without the need for an external attenuator, and without shifting the modulating voltage away from the part of the extinction ratio characteristic having the best linearity. An optical multiplexing module using semiconductor optical modulators of this type can generate a multiplexed output signal with a uniform optical power level simply by controlling the direct-current voltages applied to the semiconductor optical modulators.
    Type: Grant
    Filed: September 25, 2002
    Date of Patent: June 8, 2004
    Assignee: Oki Electric Industry Co., Ltd.
    Inventors: Kozo Fujii, Yukihiro Ozeki
  • Publication number: 20040095627
    Abstract: The present invention relates to an optical modulator array that uses stepped-well continuously tunable quantum well infrared modulators in order to accomplish electronic beam modulating. The present invention involves a coherent optical beam modulating device to steer an optical beam comprising: an optical modulator array, where said optical modulator array includes a stepped quantum well doped with electrons, wherein the modulator array affects operates as at least one of a phase modulator and a light intensity modulator base upon a voltage bias applied across the modulator array. The continuous tunable quantum well modulator includes asymmetry of the unit cell that allows transitions from the ground state to the second excited state that are normally forbidden in symmetrical quantum well infrared photodetectors.
    Type: Application
    Filed: October 30, 2003
    Publication date: May 20, 2004
    Inventors: John S. Ahearn, Mani Sundaram, Axel Reisinger
  • Publication number: 20040090659
    Abstract: A method of tuning an electroabsorption modulator (EAM). A reference average power loss factor for light having a reference peak wavelength that is modulated by the EAM is provided. This loss factor is based on operation of the EAM using a reference bias voltage, a reference temperature, and a reference modulation signal which has a predetermined duty cycle. Input light is coupled into the EAM and modulated using a modulation signal which has the same duty cycle as the reference modulation signal. The input power of the input light and the average output power of light emitted from the EAM are measured. These input and average output powers are used to generate an average power loss factor. The average power loss factor is compared to the reference average power loss factor and the bias voltage and/or the temperature of the EAM are adjusted to reduce differences between these loss factors.
    Type: Application
    Filed: August 25, 2003
    Publication date: May 13, 2004
    Inventors: Liyan Zhang, Newton C. Frateschi, Jiaming Zhang, Aaron Bond
  • Patent number: 6724517
    Abstract: A deformable mirror (10) with an at least quasi-continuously deformable optically effective surface (12) has a floatingly supported mirror plate (11) which is positioned along its edge by a portion of the adjusting members (14.1), whereas the other portion of the adjusting members (14.2) locally individually deforms the mirror plate (11) for the purposes of wave front correction. In that respect all adjusting members (14.1, 14.2) are fixed to the rear side (13) of the mirror plate (11), with a coupling portion (11) which is provided with a desired-flexion location (constriction (25)).
    Type: Grant
    Filed: December 10, 2002
    Date of Patent: April 20, 2004
    Assignee: Diehl Munitionssysteme GmbH & Co. KG
    Inventors: Klaus Bär, Berndt Warm
  • Patent number: 6717709
    Abstract: An electro absorption modulator in which the photocurrent generated by the absorption of light is monitored and the bias voltage applied to the electro absorption modulator is varied in order to vary the photocurrent and thence the extinction ratio of the electro absorption modulator.
    Type: Grant
    Filed: July 17, 2002
    Date of Patent: April 6, 2004
    Assignee: Agilent Technologies, Inc.
    Inventor: Christopher Anthony Park
  • Patent number: 6707587
    Abstract: A method and apparatus for providing tunable second-order polarization mode dispersion with constant mean first-order differential group delay for fiber optic transmission systems are provided. A section of fixed high birefringent optical fiber, a polarization controller, and a variable differential group delay module are provided. The polarization controller is connected to the high birefringent optical fiber section, and the variable differential group delay module is connected to the polarization controller. The variable differential group delay module is controlled to vary the second-order polarization mode dispersion values at an output of the high birefringent optical fiber section. The polarization controller is controlled to hold the mean first-order differential group delay substantially constant at the output of the high birefringent optical fiber section for each value of the second-order polarization mode dispersion at the output of the high birefringent optical fiber section.
    Type: Grant
    Filed: February 20, 2003
    Date of Patent: March 16, 2004
    Assignee: Sunrise Telecom Incorporated
    Inventor: Ke-Cai Zeng
  • Publication number: 20040036943
    Abstract: An electroabsorption modulator comprises a tandem arrangement of a conventional electroabsorption (EA) modulator element and a phase modulator element. The EA modulator element is driven by the digital data signal and the phase modulator is driven by a chirp tuning control signal, such as the complement of the data signal. By controlling the amplitude and/or bias of the chirp tuning control signal, the frequency chirp of the intensity-modulated output signal from the EA modulator element can be controlled.
    Type: Application
    Filed: August 22, 2002
    Publication date: February 26, 2004
    Inventors: Joseph Michael Freund, Thomas Gordon Beck Mason, Joseph Patrick Reynolds, Robert Ehrler Tench, Frank Stephen Walters
  • Publication number: 20040027634
    Abstract: An exemplary monolithic stabilized monolithic transmissive active optical device, such as an electroabsorption modulator (EAM), a variable optical attenuator (VOA), or a semiconductor optical amplifier (SOA), with an output optical tap, is formed from: a substrate; a waveguide layer; a semiconductor layer. The waveguide layer is coupled to the substrate and includes an active medium, which interacts with a predetermined wavelength of light, and is responsive to an electric signal. The electric signal is applied between the substrate and the semiconductor layer. The waveguide layer includes an output optical tap section and an active section adjacent to the output optical tap section. These sections include portions of the active medium. Further embodiments of the present invention incorporate temperature as well as bias control to improve performance of exemplary monolithic transmissive active optical devices.
    Type: Application
    Filed: August 6, 2003
    Publication date: February 12, 2004
    Inventors: Aaron Bond, John Kai Andersen, Ram Jambunathan
  • Publication number: 20040027633
    Abstract: An impedance matching circuit for an electroabsorption optical modulator addresses the conflicting concerns of being located electrically “near” the modulator, while being disposed on a separate piece part, by using an inductor as a low frequency impedance matching component, the inductor disposed in series between an off-chip high frequency impedance matching circuit and the electroabsorption optical modulator. By separating the impedance matching requirements into separate “low” and “high” frequency components, the series inductor may be used to provide the necessary low frequency impedance matching, while also forming the required physical separation between the electroabsorption optical modulator and the (conventional) high frequency impedance matching circuit.
    Type: Application
    Filed: August 7, 2002
    Publication date: February 12, 2004
    Inventors: Thomas James Miller, James Kevin Plourde
  • Publication number: 20040001242
    Abstract: An optical modulator having a good reflection characteristic over a broad band is provided, with a small semiconductor chip area, by use of a semiconductor chip on which a semiconductor optical modulator is mounted. A typical example of the optical modulator has a structure in which a semiconductor chip provided with an electro-absorption semiconductor optical modulator comprising an electrode of traveling wave modulator is mounted on a dielectric substrate provided with a transmission line, and the characteristic impedance of at least a part of the transmission line is set to be greater than the output impedance of a modulator driver circuit and the impedance of an optical modulator portion. By this, a broad band optical modulator with excellent reflection characteristic can be provided by use of a semiconductor chip which is small in area.
    Type: Application
    Filed: June 12, 2003
    Publication date: January 1, 2004
    Inventors: Junji Shigeta, Masataka Shirai, Shinji Tsuji, Hideo Arimoto
  • Publication number: 20040001243
    Abstract: A semiconductor optical modulator of an electroabsorption type includes a light absorption layer (12) for generating a modulated light beam by absorbing an incident light beam (L1). A well layer (18) is formed in the light absorption layer, and the carriers generated by the light absorption layer are accumulated in the well layer and guided and released from the well layer upon receipt of an incident excitation light beam (L2) of a wavelength corresponding to the bandgap energy of the well layer. The incident light beam is modulated by use of changes in absorption coefficient under an externally applied voltage based on the Franz-Keldysh effect or the quantum confined Stark effect, thus allowing to respond to high-intensity incident light beam at high frequency, free from deterioration of extinction characteristics, having good transmission characteristics.
    Type: Application
    Filed: June 19, 2003
    Publication date: January 1, 2004
    Applicant: Mitsubishi Denki Kabushiki Kaisha
    Inventor: Kazuhisa Takagi
  • Publication number: 20030234969
    Abstract: An optical modulator drive circuit provides a different approach to driving an optical modulator than presently employed, resulting in a reduction in power dissipation of the drive circuit by as much as about 80%. Therefore, this invention dissipates as little as 20% of power of the present drive circuits known in the art. The optical modulator may be a semiconductor electro-absorption modulator but the principle of the invention can be applied any other type of electro-optic modulator that relies on a voltage to modulate an optical signal.
    Type: Application
    Filed: December 11, 2002
    Publication date: December 25, 2003
    Inventors: Jeffrey S. Bostak, Ting-Kuang Chiang
  • Patent number: 6665105
    Abstract: A tunable modulator includes an epitaxial structure formed on a substrate. The epitaxial structure includes a waveguide for light guiding, generally in form of a ridge, a trench for thermal insulation and an integrated heating element which, when a current is passed therethrough, heats the modulator and in turn changes the effective bandgap. This alters the wavelength that is best modulated resulting in a tunable modulator in accordance with the present invention. Literature [1] Beck Mason, Greg A. Fish, Steven P. DenBaars, Larry A. Coldren, “Widely Tunable Sampled Grating DBR Laser with Integrated Electroabsorption Modulator,” IEEE Photonics Technology Letters, vol. 11, no. 6 pp. Jun. 4-6, 1999 FIG. 4. [2] Lucent/Agere Application Note TN00008 on electro-absorption modulators (EML), May 2000.
    Type: Grant
    Filed: July 31, 2001
    Date of Patent: December 16, 2003
    Assignee: Agility Communications, Inc.
    Inventor: Torsten Wipiejewski
  • Patent number: 6654152
    Abstract: Wavelength locked feedback loops are provided in frequency guide filters, and particularly in sliding frequency guide filters, wherein the wavelength locked feedback loop allows precise control over the location of the filter center wavelength with respect to a transmitted soliton center wavelength, compensating for factors such as the filter rolloff, signal spectral width, and changes in the transmission line properties due to temperature, microbending, aging and other effects. This approach allows the construction of very inexpensive frequency guiding filters, which can be based on low precision frequency domain filters with active compensation. These advantages make it possible to design new types of dispersion managed soliton optical transmission networks.
    Type: Grant
    Filed: September 25, 2001
    Date of Patent: November 25, 2003
    Assignee: International Business Machines Corporation
    Inventors: Lawrence Jacobowitz, Casimer M. DeCusatis
  • Patent number: 6646801
    Abstract: A system and method for reducing glare is provided in accordance with the present invention. The system may include a first polarizer transmitter for filtering light from a source, and a second polarizer analyzer for viewing the light received from the first polarizer. The first polarizer provides an unmatched polarization characteristic with the second polarizer to mitigate glare. The first polarizer may include a linear polarizer and the second polarizer may include at least one of a circular polarizer and/or an elliptical polarizer.
    Type: Grant
    Filed: June 9, 2000
    Date of Patent: November 11, 2003
    Inventor: Benjamin Sley
  • Publication number: 20030206327
    Abstract: The disclosed invention provides a variable lenslet array system that comprises an acousto-optic medium and at least one acoustic wave generator that is positioned adjacent to the acousto-optic medium. The acoustic wave generator is adapted to generate standing acoustic waves into the acousto-optic medium. The wavelength of the resonant acoustic waves is variable in respect to the medium dimensions or can be varied by changing the driving frequency of the wave generator. The standing acoustic waves within the acousto-optic medium change locally the index of refraction. A wave front of a light beam, which crosses these periodic changes of the index of refraction, becomes corrugated and effectively, an array of lenslets is formed.
    Type: Application
    Filed: May 3, 2002
    Publication date: November 6, 2003
    Inventor: Erez N. Ribak
  • Patent number: 6628448
    Abstract: An optical spectrum slicer capable of converting and outputting discontinuous spectrum lights having spectral components at a desired wavelength spacing from a broad band continuous spectrum light, with a simple constitution and at a reduced cost, the slider comprising a birefringent device having two polarization axes each orthogonal to an optical axis (z) and linear polarizers disposed at the light incident end and the light emission end thereof, with the direction of polarization being inclined by about 45° relative to each of polarization axes, and a heat generator for controlling the temperature of the birefringent device thereby variably controlling each of wavelengths while maintaining the wavelength spacing of the discontinuous spectrum lights.
    Type: Grant
    Filed: July 16, 2001
    Date of Patent: September 30, 2003
    Assignee: Moritex Corporation
    Inventors: Yoshihiro Ohtsuka, Koji Horio, Syumei Tokuyama
  • Patent number: 6620863
    Abstract: A damage resistant and tolerant optical element is disclosed. Prior art solid or liquid host matrices are replaced by a soft crosslinked polymer or similar host material. The viscoelastic properties of the matrix host material are controlled during formation so that there are regions of different softness, of stiffness, within the matrix, to form a stiffness gradient. Preferably, the matrix will be softest at a preselected focal plane where maximum electromagnetic radiation or energy output may be expected. The host matrix is doped with a light altering dopant having a concentration distribution, preferably such that the concentration of light limiting dopant is highest in the region where the host matrix material is most soft. Two important disclosed example embodiments are an optical limiter and a solid state dye laser.
    Type: Grant
    Filed: June 5, 2001
    Date of Patent: September 16, 2003
    Assignee: The United States of America as represented by the Secretary of the Air Force
    Inventors: Daniel G. McLean, Michael E. DeRosa, Donna M. Brandelik, Angela L. Campbell, Mark C. Brant
  • Publication number: 20030164999
    Abstract: An optical modulator which is capable of lowering the degree of chirping without deteriorating the extinction characteristic. An intermediate layer is interposed between a well layer and an n-side barrier layer and tensile strain is produced in the well layer, whereby a relationship Ew<Em<Eb is established between a band gap Eb (eV) of the barrier layer, the band gap Ew (eV) of the well layer, and the band gap Em (eV) of the intermediate layer. Another type of tensile strain quantum well structure having four kinds of layers may be formed by adding another layer to the above tensile strain quantum well structure having three kinds of layers. The band gap of an additional layer is set between the band gaps of the well layer and the intermediate layer or between the band gaps of the intermediate layer and the barrier layer.
    Type: Application
    Filed: September 5, 2002
    Publication date: September 4, 2003
    Applicant: Mitsubishi Denki Kabushiki Kaisha
    Inventor: Yasunori Miyazaki
  • Patent number: 6611085
    Abstract: A photonically engineered incandescence is disclosed. The emitter materials and photonic crystal structure can be chosen to modify or suppress thermal radiation above a cutoff wavelength, causing the emitter to selectively emit in the visible and near-infrared portions of the spectrum. An efficient incandescent lamp is enabled thereby. A method for fabricating a three-dimensional photonic crystal of a structural material, suitable for the incandescent emitter, is also disclosed.
    Type: Grant
    Filed: August 27, 2001
    Date of Patent: August 26, 2003
    Assignee: Sandia Corporation
    Inventors: James M. Gee, Shawn-Yu Lin, James G. Fleming, James B. Moreno
  • Publication number: 20030133176
    Abstract: A modulator including: a plurality of branches; first and second RF electrodes; a first plurality of RF delay elements coupled to the first RF electrode and a second plurality of RF delay elements coupled to the second electrode; and, a plurality of electro-refractive resonant elements. Each of the electro-refractive resonant elements is respectively coupled to a corresponding one of the RF delay elements and evanescently coupled to at least one of the branches.
    Type: Application
    Filed: November 13, 2002
    Publication date: July 17, 2003
    Inventor: Joseph H. Abeles
  • Publication number: 20030117681
    Abstract: An asymmetric Fabry-Perot modulator is disclosed having an adjustable resonant cavity length. A preferred embodiment of the invention includes an asymmetric Fabry-Perot modulator having a first reflector adjustably mounted to another portion of the modulator containing a second reflector. The length of the resonant cavity is adjusted by microelectomechanically changing the distance from the first reflector to the second reflector. In turn, this change of the resonant cavity length may tune the modulator to an optimal wavelength corresponding to the electro-absorptance material in the modulator.
    Type: Application
    Filed: December 26, 2001
    Publication date: June 26, 2003
    Inventor: Parviz Tayebati
  • Patent number: 6580540
    Abstract: A time compensation architecture for use with a plurality of optical signals is disclosed. It comprises means for receiving the plurality of optical signals, optical means for selectively delaying the propagation of each of the plurality of optical signals, and means for outputting the time delayed optical signals. The delay may be achieved by changing the indices of refraction or the material lengths of the elements and can either be an active or a passive compensation technique.
    Type: Grant
    Filed: June 2, 2000
    Date of Patent: June 17, 2003
    Assignee: Northrop Grumman Corporation
    Inventor: Stephen P. Palese
  • Publication number: 20030095764
    Abstract: A biochemical assay device optically scans individual biological sample containing wells in an assay plate. The device includes an imaging system overlaying the assay plate wherein a scanning light propagates by total internal reflection within an optical waveguide. The waveguide includes a plurality of pixel locations, each aligned with a well in the assay plate, at which total internal reflection is selectively frustrated to output an incident beam of light. That light illuminates the well and causes generation of an emission beam of light that is detected by a photoreceptor. The device further includes a driver circuit that controls the selective frustration of total internal reflection at each pixel location in order to scan each well in the assay plate. A processor is also included in the device to process the detected emission beams of light generated by the scanned wells for purposes of assaying the biological sample contained in each scanned well.
    Type: Application
    Filed: November 20, 2001
    Publication date: May 22, 2003
    Inventors: Richard D. Pering, David A. King, Richard A. Pittaro, Shahida Rana, Frederick A. Stawitcke, Edward D. Verdonk
  • Publication number: 20030081301
    Abstract: A semiconductor optical modulator having an electroabsorptive layer and a pair of modulating voltage electrodes also has a direct-current voltage electrode, from which an unmodulated electric field can be applied to the electroabsorptive layer to adjust the output optical power level. The output optical power level can thus be adjusted without the need for an external attenuator, and without shifting the modulating voltage away from the part of the extinction ratio characteristic having the best linearity. An optical multiplexing module using semiconductor optical modulators of this type can generate a multiplexed output signal with a uniform optical power level simply by controlling the direct-current voltages applied to the semiconductor optical modulators.
    Type: Application
    Filed: September 25, 2002
    Publication date: May 1, 2003
    Applicant: Oki Electric Industry Co., Ltd.
    Inventors: Kozo Fujii, Yukihiro Ozeki
  • Publication number: 20030063362
    Abstract: This invention relates to a semiconductor device for switching or modulating optical signals, cross-connects and switches built of such devices as well as a method of switching or modulating optical signals. The semiconductor device has a photodetector having a low electrical capacitance Cd, a detector absorbing layer for absorbing an optical signal beam, a modulator having a low capacitance Cm and a modulator absorbing layer exhibiting an electric field-dependent absorption coefficient. The modulator absorbing layer is used for absorbing an optical power beam, which is to be modulated or switched. The device has a low resistivity region between the photodetector and the modulator such that the electric field-dependent absorption coefficient is altered uniformly and rapidly throughout the modulator absorbing layer during absorption of the optical signal beam in the detector absorbing layer.
    Type: Application
    Filed: February 13, 2002
    Publication date: April 3, 2003
    Inventors: Hilmi Volkan Demir, David A.B. Miller, Vijit Sabnis
  • Patent number: 6535326
    Abstract: An electrophoretic display device includes a first display electrode and a second display electrode placed on a first substrate, and a second substrate placed in opposition to the first substrate through a bulkhead. Auxiliary display electrodes (projections), each of a projecting structure, are provided on the first display electrode and the second display electrode and along lines of portions where an absolute value of a horizontal component of an electric field generated over the first display electrode and the second display electrode, becomes minimum. A space formed by the first substrate, the second substrate, and the bulkhead is filled with a transparent insulating liquid, and colored electrophoretic particles are dispersed in the insulating liquid.
    Type: Grant
    Filed: November 9, 2001
    Date of Patent: March 18, 2003
    Assignee: Canon Kabushiki Kaisha
    Inventor: Yoshinori Uno
  • Patent number: 6525859
    Abstract: The present invention pertains to an optical shutter comprising an organic free compound, such as a radical cation or a radical anion, and a polydiacetylene compound, wherein the polydiacetylene compound is characterized by having a change in absorption in a wavelength region as a result of a photo-induced heat transfer from the free radical compound. The thermochromic change in absorption is reversed by thermal cooling or by a photo-induced reaction after the photo-induced heat transfer. Also provided is an optical shutter for use as an optical switch in fiber optic communications, and, alternatively, for use in a laser protection device, in a security protection system, or in an eyewear device.
    Type: Grant
    Filed: April 18, 2001
    Date of Patent: February 25, 2003
    Assignee: Optodot Corporation
    Inventor: Steven A. Carlson
  • Publication number: 20030035201
    Abstract: Wavelength conversion apparatus is described that utilizes a Kerr cell to modulate the polarization of a pump laser beam having a first wavelength before the beam is input to a optical parametric oscillator/amplifier wavelength converter to generate a laser beam having a second wavelength. By modulating the polarization of the pump laser beam using the Kerr cell, the optical wavelength converter can be controlled to switch on and off or otherwise amplitude modulate the second wavelength laser beam output from the converter, and to correspondingly amplitude modulate the first wavelength and all other laser beams being output from the converter. In addition, with the pump laser beam and the second wavelength laser beam always being output from said wavelength converter there is a substantially constant thermal load on said wavelength converter creating substantially constant thermal lensing in the wavelength converter crystal that may be easily compensated using optical means.
    Type: Application
    Filed: July 27, 2002
    Publication date: February 20, 2003
    Inventor: Peter A. Budni
  • Publication number: 20030035610
    Abstract: An optical phase modulator includes a bandpass multilayer stack, formed by a plurality of dielectric layers, preferably of GaAs and AlAs, and having a transmission function related to the refractive index of the layers of the stack, for receiving an optical input signal to be phase modulated. A phase modulator device produces a nonmechanical change in the refractive index of each layer of the stack by, e.g., the injection of free carrier, to provide shifting of the transmission function so as to produce phase modulation of the optical input signal and to thereby produce a phase modulated output signal.
    Type: Application
    Filed: June 6, 2001
    Publication date: February 20, 2003
    Inventors: Andrew S. Keys, Richard L. Fork
  • Patent number: 6522450
    Abstract: An apparatus and method of chromatic dispersion includes the negative compensation per channel filter (130) coupled to an optical receiving path (100) for providing a lossless discontinuous per-channel dispersion compensation in the optical receiving path (100). The optical receiving path (100) includes an input port (131), at the input of the filter (130), for receiving an input optical pulse (120) having a packet of waves at corresponding frequencies transmitted and received by an optical fiber (115).
    Type: Grant
    Filed: April 25, 2001
    Date of Patent: February 18, 2003
    Assignee: Corning Incorporated
    Inventor: Luis A. Zenteno
  • Publication number: 20030030880
    Abstract: A method of reducing the appearance of speckle resulting from a coherent light beam, includes the steps of: providing an electro-optic device having, an electro-optic substrate, an electrode array arranged on the surface of the electro-optic substrate, at least one electrode located on the opposite surface of the electro-optic substrate, and means for applying voltage to the electrodes to generate a variation in a refractive index profile within the substrate; and directing the light beam through the electro-optic device while applying voltage to the device, whereby the temporal and spatial phase of a light beam passing through the substrate is altered, thereby reducing the appearance of speckle..
    Type: Application
    Filed: August 8, 2001
    Publication date: February 13, 2003
    Applicant: Eastman Kodak Company
    Inventors: Sujatha Ramanujan, Andrew F. Kurtz
  • Publication number: 20030025976
    Abstract: A tunable modulator includes an epitaxial structure formed on a substrate. The epitaxial structure includes a waveguide for light guiding, generally in form of a ridge, a trench for thermal insulation and an integrated heating element which, when a current is passed therethrough, heats the modulator and in turn changes the effective bandgap. This alters the wavelength that is best modulated resulting in a tunable modulator in accordance with the present invention.
    Type: Application
    Filed: July 31, 2001
    Publication date: February 6, 2003
    Inventor: Torsten Wipiejewski
  • Publication number: 20030021006
    Abstract: The invention concerns an optical device for wavelength interleaving or dissociation (1) comprising means for coupling (4) a luminous flux generated by a source (3) in an input fiber (2), a circulator (5) linked to this input fiber (2) and to an output fiber (7) forming a first output gate of the optical device (1), a polarisation beam splitter (9) receiving the luminous flux coming out of the circulator (5) and separating it into two components (r1) and (r2). It also comprises means for transferring (14) the luminous flux from one output to the other, a birefringent medium (15) interposed on the optical path and a fiber (16) forming a second output of the optical device (1).
    Type: Application
    Filed: March 19, 2002
    Publication date: January 30, 2003
    Inventor: Philippe Martin
  • Patent number: 6493131
    Abstract: A device is used to wavelength lock two optical signals to some frequency offset. A photomixer section produces a frequency test signal from the beat component of the two optical signals. The frequency of the frequency test signal reflects whether the actual frequency offset of the two optical signals equals the desired offset. A frequency filter with a monotonically varying transfer function is used to filter the frequency test signal. Thus, different gains are applied to different frequencies. Comparison circuitry uses the filtered signal to determine whether the frequency filter applied the gain which corresponds to the desired frequency offset and generates a corresponding error signal.
    Type: Grant
    Filed: December 20, 2000
    Date of Patent: December 10, 2002
    Assignee: Kestrel Solutions, Inc.
    Inventors: Shin-Sheng Tarng, Slava Yazhgur, Ting K. Yee, Peter H. Chang
  • Publication number: 20020171912
    Abstract: A laser light generating apparatus is provided with a laser light source, a phase modulator, a signal generating unit for applying a modulating signal to the phase modulator, and resonators. A nonlinear optical element is provided in the resonator, and an optical path length varying means for changing length of an optical path of each of the resonators is provided. Error signals are obtained using detection signals of photodetectors for receiving light from the resonators, respectively, and the optical path length varying means is controlled by a sideband method, whereby a control circuit having a negative feedback configuration for controlling length of the resonators is formed. Laser light is subjected to phase modulation and then inputted to the resonator, and light generated by the nonlinear optical element is inputted to the resonator so that the plurality of resonators are simultaneously held in a resonant state.
    Type: Application
    Filed: April 10, 2002
    Publication date: November 21, 2002
    Applicant: Sony Corporation
    Inventor: Hisashi Masuda
  • Patent number: 6472682
    Abstract: An optical modulator and a semiconductor laser device including the optical modulator, both reducing variations in the refractive index of an optical modulator or making variations negative without an increase in loss or a decrease in extinction ratio, as well as an optical communications system increasing an interval of distance at which modulated light is transmitted, by use of the optical modulator and the semiconductor laser device including the optical modulator. The optical modulator includes a semiconductor substrate of a first conductivity type; a light absorption layer on the semiconductor substrate and having a multiple quantum well structure, the multiple quantum well structure including a first well layer and second well layers. The peak wavelength of the absorption spectrum of the second well layers is shorter than the peak wavelength of the absorption spectrum of the first well layers A semiconductor cladding layer of the second conductivity type is on the light absorption layer.
    Type: Grant
    Filed: October 26, 2000
    Date of Patent: October 29, 2002
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventor: Kyosuke Kuramoto
  • Publication number: 20020131140
    Abstract: An apparatus for stabilized photonic transmission is described. A light source of limited coherence length is wavelength shifted, stabilized, and data encoded to provide a stabilized photonic signal. A modulation synthesizer provides a modulation waveform embedded with the shifting, stabilization and data encoding mechanisms. A variety of modulation devices are supported. The modulation waveform is optimized for the particular modulation device. A wavelength error detector provides feedback to the modulation synthesizer. The error signal is used to stabilize the photonic signal and correct channel wavelength errors. Fixed wavelength channels and spread spectrum channels are supported.
    Type: Application
    Filed: March 16, 2001
    Publication date: September 19, 2002
    Inventors: Michael H. Myers, Juan C. Riley, Charles D. Melville
  • Patent number: 6424448
    Abstract: An antiglare optical device for selectively attenuating bright light sources in an object field. This device comprises at the object end, the optics necessary for focusing incoming rays onto a focal plane, at the eyepiece end, the optics necessary to view the image of the object field, and at the focal plane, a photochromic layer for moderating rays originating from intense objects in the object field. A sharp focusing of the object field on the photochromic layer is achieved by means of asymmetrical optical components such as polarizing beam splitter and half lenses.
    Type: Grant
    Filed: July 20, 1999
    Date of Patent: July 23, 2002
    Inventor: George Samuel Levy
  • Patent number: 6388795
    Abstract: A new class of structured dielectric media which exhibit significant photonic bandstructure has been invented. The new structures, called photonic layered media, are easy to fabricate using existing layer-by-layer growth techniques, and offer the ability to significantly extend our practical ability to tailor the properties of such optical materials.
    Type: Grant
    Filed: May 11, 2000
    Date of Patent: May 14, 2002
    Assignee: Sandia Corporation
    Inventors: James G. Fleming, Shawn-Yu Lin
  • Patent number: 6385354
    Abstract: An apparatus modulates the phase of an optical signal. The apparatus includes an optical medium for propagating the optical signal. At least one electrode is positioned in proximity with the medium. The electrode induces an electric field within the medium in response to an AC voltage to produce variations in the index of refraction of the optical medium through the electrostrictive effect. Preferably, the phase of the optical signal is modulated such that polarization components of the optical signal parallel to and orthogonal to the electric field experience an equal phase shift. In certain embodiments, a DC voltage is supplied to the optical medium. Alternatively, the DC voltage within the optical medium may arise from (or be enhanced by) poling the optical medium. Certain embodiments of the present invention include two electrodes positioned on opposite sides of the optical medium.
    Type: Grant
    Filed: March 1, 1999
    Date of Patent: May 7, 2002
    Assignee: The Board of Trustees of the Leland Stanford Junior University
    Inventors: Michel J. F. Digonnet, Alice Liu, Gordon S. Kino
  • Publication number: 20020051275
    Abstract: A photonic crystal comprises a plurality of elongated elements formed of a first dielectric material and arranged in a two-dimensional periodic honeycomb lattice. A second dielectric material surrounds the elongated elements and extending between them. The second dielectric material defines between the elongated elements a plurality of spaces filled with a third dielectric material. The first dielectric material has permittivity that is greater than permittivity of the second dielectric material and permittivity of the third dielectric material.
    Type: Application
    Filed: December 4, 2001
    Publication date: May 2, 2002
    Inventor: Masatoshi Tokushima
  • Patent number: 6380109
    Abstract: There is disclosed second-order nonlinear glass material wherein a part having second-order nonlinearity contain Ge, H and OH and second-order nonlinear optical constant d of 1 pm/V or more, and a method for producing second-order nonliner glass material comprising treating a porous class material containing Ge with hydrohen, sintering it and subjecting it to a ultraviolet poling treatment. There can be provided second-order nonlinger glass material having second-order nonlinearity which is a sufficiently high and has a sufficiently long lifetime for a practical purpose, in use of the glass material for optical elements or the like.
    Type: Grant
    Filed: February 23, 2000
    Date of Patent: April 30, 2002
    Assignees: Shin-Etsu Chemical Co., Ltd., Toyota Tecnological Institute
    Inventors: Jun Abe, Seiki Ejima, Akira J. Ikushima, Takumi Fujiwara
  • Publication number: 20020048074
    Abstract: An optical spectrum slicer capable of converting and outputting discontinuous spectrum lights having spectral components at a desired wavelength spacing from a broad band continuous spectrum light, with a simple constitution and at a reduced cost, the slider comprising a birefringent device having two polarization axes each orthogonal to an optical axis (z) and linear polarizers disposed at the light incident end and the light emission end thereof, with the direction of polarization being inclined by about 45° relative to each of polarization axes, and a heat generator for controlling the temperature of the birefringent device thereby variably controlling each of wavelengths while maintaining the wavelength spacing of the discontinuous spectrum lights.
    Type: Application
    Filed: July 16, 2001
    Publication date: April 25, 2002
    Applicant: MORITEX CORPORATION
    Inventors: Yoshihiro Ohtsuka, Koji Horio, Syumei Tokuyama