Patents Examined by Rodney B. Bovernick
  • Patent number: 7447387
    Abstract: An electro-optical modulator includes a structural substrate having insulating layer. A waveguide layer is on the insulating layer. A resonant layer on the insulating layer has a curving rim adjacent to the waveguide layer to form an optical coupling region. A gate dielectric layer covers part of the resonant layer. A dielectric layer over the resonant layer covers the gate dielectric layer. The dielectric layer has a first opening exposing part of the resonant layer and a second opening exposing the gate dielectric layer. Part of the second opening is adjacent to the curving rim of the resonant layer. A first polysilicon layer on the exposed region of the resonant layer serves as an electrode. A second polysilicon layer over the dielectric layer fills the second opening and is in contact with the gate dielectric layer. Part of the second polysilicon layer covering the dielectric layer serves as an electrode.
    Type: Grant
    Filed: November 24, 2006
    Date of Patent: November 4, 2008
    Assignee: Industrial Technology Research Institute
    Inventors: Chih-Tsung Shih, Huai-Yi Chen, Shiuh Chao, Shin-Ge Lee
  • Patent number: 7181103
    Abstract: An optical apparatus comprises an optical interconnect structure defining one or more optical source and receiver ports and one or more interconnect optical signal pathways connecting corresponding optical signal source and receiver ports. The optical interconnect structure comprises an optical waveguide defining a portion of each interconnect optical signal pathway. Each interconnect pathway includes a wavefront diffractive transformation region and a corresponding set of diffractive elements thereof. Each diffractive element set diffractively transforms a corresponding diffracted portion of an incident signal with a corresponding design input signal wavefront into an emergent signal with a corresponding design output signal wavefront. For at least one diffractive element set, only one of the corresponding design input or output signal wavefronts is confined in at least one transverse dimension by the optical waveguide, while the other design wavefront propagates without confinement by the optical waveguide.
    Type: Grant
    Filed: February 17, 2005
    Date of Patent: February 20, 2007
    Assignee: LightSmyth Technologies Inc
    Inventors: Christoph M. Greiner, Dmitri Iazikov, Thomas W. Mossberg
  • Patent number: 7118290
    Abstract: A ferrule block comprises a ferrule block body which is attached to an optical device module, which houses in its package an optical device for sending or receiving a light signal, to optically couple to an optical fiber communicating between the optical device module and an external optical communication system and a shell made of an insulating material which is provided at the tip of the ferrule block body, wherein a flange which hits against the tip of the ferrule block body is provided on the outer periphery of the shell.
    Type: Grant
    Filed: November 12, 2004
    Date of Patent: October 10, 2006
    Assignee: Hitachi Cable, Ltd.
    Inventors: Yoshiaki Ishigami, Yoshinori Sunaga
  • Patent number: 6139195
    Abstract: An optical fiber connector having strain relief insert means to engage the buffered coating of the optical fiber cable upon the crimping of a crimp ring to cause the insert to flow in a direction toward the connector and the fiber to move toward the connector.
    Type: Grant
    Filed: May 22, 1996
    Date of Patent: October 31, 2000
    Assignee: Minnesota Mining and Manufacturing Company
    Inventor: Joseph A. Paparella
  • Patent number: 6081643
    Abstract: A wave guide or an assembly of wave guides, characterized in that each wave guide meets the conditions that: 1) at least one of the characteristics of the wave guide is of the same order of magnitude as the largest absolute value of the de Broglie wavelength .lambda..sub.b of a particle or a collectivity of particles moving or able to move through the wave guide; 2) the dimensions of the irregularities of the wall of the wave guide are small with respect to .vertline..lambda..sub.c .vertline., the absolute value of the cutoff wavelength .lambda..sub.c of the wave guide, with the property that for each particle with de Broglie wavelength .lambda..sub.b that moves in the wave guide, holds .vertline..lambda..sub.b .vertline..ltoreq..vertline..lambda..sub.c .vertline.; and 3) .lambda..sub.
    Type: Grant
    Filed: September 12, 1996
    Date of Patent: June 27, 2000
    Inventor: Willem Lentink
  • Patent number: 6078601
    Abstract: A control method is provided by which a laser output can be controlled through the use of a signal provided by a photodiode that receives a reflected ratio of the laser output signal. A time varying signal is added to the low magnitude portions of an electrical data input signal to the laser. This first electrical monitoring signal, which is essentially an average output from the photodiode because of its frequency response, is then passed through a low pass filter to provide a second electrical monitoring signal. The first electrical monitoring signal is multiplied by a time varying signal to provide a third electrical monitoring signal. The time varying signal, which can be a sinusoidal waveform, is added to the low magnitude portions of an electrical input signal provided to the laser. The third electrical monitoring signal is averaged over time by a low pass filter to provide a fourth electrical monitoring signal.
    Type: Grant
    Filed: March 7, 1997
    Date of Patent: June 20, 2000
    Inventor: David F. Smith
  • Patent number: 6004044
    Abstract: An optoelectric connector (12, FIG. 2) is described, which has an outer end (96) constructed to efficiently couple to an optical fiber connector (14) and which has an inner end (47) with electrical contacts (46) for passing currents representing modulated light received or transmitted to an optical cable (20) attached to the optical connector. The optoelectric connector (12) includes a stub (80) or short length of optical fiber with an outer end (82) held at a coupling that couples to the optical fiber (24) of the cable in the same manner as a pair of long optical fibers are connected to minimize losses. The stub has an inner end (84) optically coupled to the optic face (42) of a photoelectric transducer (40) which is coupled to an electrical contact (46).
    Type: Grant
    Filed: May 3, 1995
    Date of Patent: December 21, 1999
    Assignee: ITT Cannon, Inc.
    Inventors: Eric James Paulus, Scott Allen Zehrung
  • Patent number: 5986778
    Abstract: Bow can be minimized by an auxiliary grating in a post deflection path of the diffracted beam from the hologon which is disposed in non-parallel relationship to the plane of rotation of the hologon. The ellipticity of the spot which generates the scan line and intensity variation in the scan beam can be minimized by using a dispersive element, preferably a prism, between the hologon and the bow compensation grating with its dispersion in a direction opposite to the direction of the dispersion of the hologon and of the auxiliary grating. Another grating before the hologon can be used to correct for wavelength shift induced cross-scan error associated with the dispersion in the hologon and a bow compensation grating following the hologon.
    Type: Grant
    Filed: September 4, 1990
    Date of Patent: November 16, 1999
    Assignee: Holotek Ltd.
    Inventor: Charles J. Kramer
  • Patent number: 5936991
    Abstract: Conventional master oscillator power amplifier (MOPA) devices have experienced poor beam quality due to edge effects. The lateral current tailoring described herein was one attempt at improving the laser beam quality. Experimental results have indicated that this approach can make improvement in beam quality, using nonlinear leading edges in the gain stripe of MOPA amplifiers.
    Type: Grant
    Filed: September 17, 1996
    Date of Patent: August 10, 1999
    Assignee: The United States of America as represented by the Secretary of the Air Force
    Inventors: Robert J. Lang, David A. Mehuys, Steve O'Brien, Jo Major
  • Patent number: 5914974
    Abstract: A high voltage pulse power generating circuit capable of eliminating secondary pulses due to stage mismatch in the stages of its magnetic pulse compressor circuit is disclosed. The pulse generating circuit source comprises a high voltage charge storing element which is periodically discharged into a nonlinear magnetic compressor circuit. A mismatch correction circuit coupled to each stage of the compressor circuit discharges the reflected energy due to stage mismatch and thus eliminates the reflected energy from being launched back into the load. In a preferred embodiment, the pulse power generating circuit of the present invention utilizes a diode and a resistor that is coupled to each stage of the magnetic pulse compressor circuit. Various embodiments are disclosed.
    Type: Grant
    Filed: February 21, 1997
    Date of Patent: June 22, 1999
    Assignee: Cymer, Inc.
    Inventors: William N. Partlo, Richard L. Sandstrom, Daniel L. Birx, Richard Mons Ness
  • Patent number: 5912910
    Abstract: Laser diode pumped mid-IR wavelength systems include at least one high power, near-IR wavelength, injection and/or sources wherein one or both of such sources may be tunable providing a pump wave output beam to a quasi-phase matched (QPM) nonlinear frequency mixing (NFM) device. The NFM device may be a difference frequency mixing (DFM) device or an optical parametric oscillation (OPO) device. Wavelength tuning of at least one of the sources advantageously provides the ability for optimizing pump or injection wavelengths to match the QPM properties of the NFM device enabling a broad range of mid-IR wavelength selectivity. Also, pump powers are gain enhanced by the addition of a rare earth amplifier or oscillator, or a Raman/Brillouin amplifier or oscillator between the high power source and the NFM device. Further, polarization conversion using Raman or Brillouin wavelength shifting is provided to optimize frequency conversion efficiency in the NFM device.
    Type: Grant
    Filed: May 17, 1996
    Date of Patent: June 15, 1999
    Assignee: SDL, Inc.
    Inventors: Steven Sanders, Robert J. Lang, Robert G. Waarts
  • Patent number: 5905750
    Abstract: A semiconductor laser package including a laser chip mounted to an uppermost surface of a leadframe, and a molded structure at least partially encapsulating the laser chip. The laser chip composed of a vertical cavity surface emitting laser and an optional photodetector. The vertical cavity surface emitting laser generating an emission along a path. The molded structure including an optical element positioned a specific distance from an emission aperture of the vertical cavity surface emitting laser. The laser chip and the optical element mounted in precise z-axis alignment from the emission aperture of the vertical cavity surface emitting laser utilizing the uppermost surface of the leadframe as a dimensional reference point.
    Type: Grant
    Filed: October 15, 1996
    Date of Patent: May 18, 1999
    Assignee: Motorola, Inc.
    Inventors: Michael S. Lebby, Wenbin Jiang, John W. Stafford
  • Patent number: 5898717
    Abstract: Third harmonic generated from intra-cavity frequency tripled resonator is disclosed in which type II phase matching crystal is used as the tripler. Type I phase matching is used for second harmonic generation. The resonator efficiently converts the fundamental laser frequency to its third harmonic laser beam. The laser is highly efficient with high third harmonic output stability. Overall conversion efficiency exceeds 25% and preferably is 50% or higher.
    Type: Grant
    Filed: January 24, 1997
    Date of Patent: April 27, 1999
    Assignee: Photonics Industries International, Inc.
    Inventor: Yusong Yin
  • Patent number: 5892863
    Abstract: A thermally activated silica optical circuit switch that uses light from a light source, such as a laser, to heat various regions of the switch to produce a switching function. In one embodiment, the switch includes silica glass formed on a substrate, such as a silicon substrate, and at least one input waveguide and one output waveguide formed within the silica glass. A light source is then used to generate light that illuminates a path in the silica glass that couples a particular input waveguide to a particular output waveguide. The light from the light source has a wavelength that enables it to be substantially absorbed by the silica glass and substantially transmitted through the substrate. The illumination by the light increases the temperature and correspondingly the index of refraction of the silica glass in the path. A light signal is then able to travel through the coupled waveguides via the increased index of refraction of the silica glass within the path.
    Type: Grant
    Filed: October 18, 1996
    Date of Patent: April 6, 1999
    Assignee: Lucent Technologies Inc.
    Inventor: Herman Melvin Presby
  • Patent number: 5892784
    Abstract: The present invention provides a n-drive surface emitting laser comprised of an active region, a first mirror region having a first conductivity type, a second mirror region having a second opposite conductivity type, the first and second mirror regions being located on opposite sides of the light generation region, a buffer region having a second conductivity type, and a substrate having a first conductivity type. In the preferred embodiment the first conductivity type is n-type, thus the present invention provides a method of forming an n-drive semiconductor laser on an n-type substrate. Contact is made to the p-type mirror region via a tunnel junction formed by degeneratively doping the areas of the substrate region and the buffer region which abut each other. The tunnel junction is reverse biased so that current is injected through the degeneratively doped p-n junction formed by the n+ substrate and the p-type conducting layer.
    Type: Grant
    Filed: October 27, 1994
    Date of Patent: April 6, 1999
    Assignee: Hewlett-Packard Company
    Inventors: Michael R. T. Tan, Albert T. Yuen, Shih-Yuan Wang
  • Patent number: 5887011
    Abstract: A semiconductor laser includes a first conductivity type GaAs substrate; a AlGaAs double heterojunction structure disposed on the GaAs substrate and including an upper cladding layer having a mesa ridge stripe with a side surface that makes an angle larger than with a front surface of the upper cladding layer; a first current blocking layer of first conductivity type AlGaAs; and a second current blocking layer of first conductivity type AlGaAs, the first and second current blocking layers covering the mesa ridge stripe. The Al compositions of the first and second current blocking layers are larger than that of the upper cladding layer, maintaining an equivalent refractive index of an active region higher than that of other portions of the semiconductor laser. As a result, the differences between the lattice constant of the second current blocking layer and the GaAs substrate or the AlGaAs upper cladding layer are smaller than in prior art semiconductor lasers.
    Type: Grant
    Filed: February 18, 1997
    Date of Patent: March 23, 1999
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Yuji Ohkura, Motoharu Miyashita, Shoichi Karakida
  • Patent number: 5878073
    Abstract: A focal distance adjustable laser module including a cap having a tapered laser firing hole, a lens holder press-fitted into the cap to hold a rubber packing ring and a lens on the rubber packing ring and having an inner thread at the back side, a laser diode holder holding a mounting plate and a laser diode on the mounting plate and having an outer thread at the front side threaded into the inner thread of the lens holder, a circuit board secured to the mounting plate at the back and connected to the laser diode to control its operation, and a spring mounted inside the lens holder and imparting a backward pressure to the laser diode holder to prohibit displacement of the laser diode holder relative to the lens holder.
    Type: Grant
    Filed: December 4, 1996
    Date of Patent: March 2, 1999
    Assignee: Quarton Inc.
    Inventor: Jen-Chih Wu
  • Patent number: 5878070
    Abstract: A photonic light emitting device comprising a relatively high refractive index photonic-wire semiconductor waveguide core in the form of an arcuate shape, linear shape and combinations thereof. The waveguide core is formed into a closed loop cavity for a light-emitting device or laser. The waveguide core is surrounded on all transverse sides by relatively low refractive index medium and comprises an active medium having major and minor sides and semiconductor guiding layers proximate the major sides. The active medium and the guiding layers are so dimensioned in a transverse direction relative to the path of light propagation through the core to provide dramatically increased spontaneous-emission coupling efficiency, leaading to low lasing threshold and high intrinsic modulation rates.
    Type: Grant
    Filed: May 24, 1996
    Date of Patent: March 2, 1999
    Assignee: Northwestern University
    Inventors: Seng-Tiong Ho, Jian P. Zhang
  • Patent number: 5867616
    Abstract: A single mode optical waveguide having reduced polarization mode dispersion and a method for making such a waveguide is disclosed. Perturbations are introduced into the waveguide core to couple power between the two polarization modes. A model calculation shows that the perturbation length may be of the order of the correlation length. The inventive waveguide is robust in that polarization mode dispersion is reduced even if perturbations are impressed on the fiber after manufacture.
    Type: Grant
    Filed: August 10, 1995
    Date of Patent: February 2, 1999
    Assignee: Corning Incorporated
    Inventors: A. Joseph Antos, Venkata A. Bhagavatula, William J. Cherenak, Dipakbin Q. Chowdhury, Daniel A. Nolan
  • Patent number: 5867521
    Abstract: Surface-emitting distributed feedback (SEDFB) lasers having a curved grating with a shape that produces good beam quality. A preferred shape is one for which the grating curves away from the center of the gain region of the laser. The use of the curved grating of the present invention produces good beam quality from broad area SEDFB lasers with high power and high efficiency. The present invention overcomes self-induced filament formation and dynamic instabilities that limit achievable beam quality. The present invention provides for a holographic method for fabricating curved gratings for the SEDFB lasers that is consistent with laser batch processing.
    Type: Grant
    Filed: February 26, 1997
    Date of Patent: February 2, 1999
    Assignee: Raytheon Company
    Inventor: Steven H. Macomber