Patents Examined by James Menefee
  • Patent number: 7177339
    Abstract: A semiconductor laser has implantation regions that are effective as mode-selective regions in addition to current diaphragms in the edge region of a mesa. As a result, the inner opening of the current diaphragms can be chosen to be larger than in the prior art. This leads to a low ohmic and thermal resistance and enables a high output power.
    Type: Grant
    Filed: August 8, 2003
    Date of Patent: February 13, 2007
    Assignee: Osram Opto Semiconductors GmbH
    Inventor: Jürgen Müller
  • Patent number: 7170921
    Abstract: A magneto-optic variable optical attenuator is provided that is used to control the intensity of a light signal. The optical attenuator includes at least one polarizing element having an optical polarization axis, wherein the polarizing element transmits a portion of an incident light signal proportional to the angular difference between an optical polarization axis of the incident light signal and that of the polarizing element. The optical attenuator also comprises a variable faraday rotator that includes a semi-transparent material, a magnetic material for applying a magnetic force to a light signal that is passed through the semi-transparent material, and a conductive wire configured to induce a magnetic field on the magnetic material. In various embodiments, the optical attenuator is employed as part of a laser package that includes a laser light source and a plurality of polarizing elements, which are in optical communication with a faraday rotator and/or a variable faraday rotator.
    Type: Grant
    Filed: October 17, 2003
    Date of Patent: January 30, 2007
    Assignee: Finisar Corporation
    Inventors: William Freeman, Steve Wang, Frank H. Levinson
  • Patent number: 7166873
    Abstract: A light emitting device includes a semiconductor laser chip which emits a laser beam; a coherence reducing member which receives the laser beam and reduces coherence of the laser beam to generate a lower coherence light beam; and a package which houses the laser chip and the coherence reducing member, the package having an opening; wherein the laser beam emitted from the laser chip is converted into a lower coherence light beam by the coherence reducing member, and the lower coherence light beam is outputted through the opening.
    Type: Grant
    Filed: September 23, 2003
    Date of Patent: January 23, 2007
    Assignee: Sharp Kabushiki Kaisha
    Inventor: Jun Okazaki
  • Patent number: 7167496
    Abstract: In order to achieve a long wavelength, 1.3 micron or above, VCSEL or other semiconductor laser, layers of strained quantum well material are supported by mechanical stabilizers which are nearly lattice matched with the GaAs substrate, or lattice mismatched in the opposite direction from the quantum well material; to allow the use of ordinary deposition materials and procedures. By interspersing thin, unstrained layers of e.g. gallium arsenide in the quantum well between the strained layers of e.g. InGaAs, the GaAs layers act as mechanical stabilizers keeping the InGaAs layers thin enough to prevent lattice relaxation of the InGaAs quantum well material. Through selection of the thickness and width of the mechanical stabilizers and strained quantum well layers in the quantum well, 1.3 micron and above wavelength lasing is achieved with use of high efficiency AlGaAs mirrors and standard gallium arsenide substrates.
    Type: Grant
    Filed: August 4, 2003
    Date of Patent: January 23, 2007
    Assignee: Finisar Corporation
    Inventor: Ralph H. Johnson
  • Patent number: 7164099
    Abstract: A multi-axis laser machine in which the working efficiency can be improved even when machining positions in respective systems are different from each other. The positioning operation of a laser positioning unit for positioning an optical path of a laser beam in an axis and the positioning operation of another laser positioning unit for positioning another optical path of the laser beam in another axis are performed independently of each other. An arbitration unit monitors the laser positioning units as to whether they have finished positioning or not. The arbitration unit operates a deflection unit (AOM) so as to supply the laser beam to one of the laser positioning units which has finished positioning. Incidentally, when the laser positioning units finish positioning simultaneously, the arbitration unit supplies the laser beam to the laser positioning units in a predetermined sequence.
    Type: Grant
    Filed: December 16, 2003
    Date of Patent: January 16, 2007
    Assignee: Hitachi Via Mechancis Ltd.
    Inventors: Izumi Hata, Toshiya Nishimura, Hidenori Tateishi, Yasuyuki Shimizu, Tetsuo Murakami
  • Patent number: 7164702
    Abstract: Micro-optical elements (MOEs) are designed and fabricated onto transparent laser driver substrates to collimate or focus the beams from vertical-cavity surface-emitting lasers (VCSELs) in accordance with specific application requirements. One disclosed example teaches the hybrid integration of a top-emitting 850 mm VCSEL array and a transparent sapphire substrate that supports a monolithic MOE with designated optical functionality. A flip-chipping hybridization technique ensures a realistic and reliable process. The VCSEL beams transmit directly through the MOE structure on the transparent sapphire substrate and become well-controlled optical outputs under precise specifications. The optical power loss in such a beam shaping process is minimized compared to configurations based on conventional optical components.
    Type: Grant
    Filed: August 29, 2003
    Date of Patent: January 16, 2007
    Assignee: The United States of America as represented by the Secretary of the Army
    Inventors: Jony Jiang Liu, George J. Simonis
  • Patent number: 7160749
    Abstract: The polarization instability inherent in laterally-oxidized VCSELs may be mitigated by employing an appropriately-shaped device aperture, a misoriented substrate, one or more cavities or employing the shaped device aperture together with a misoriented substrate and/or cavities. The laterally-oxidized VCSELs are able to operate in a single polarization mode throughout the entire light output power versus intensity curve. Combining the use of misoriented substrates with a device design that has an asymmetric aperture that reinforces the polarization mode favored by the substrate further improves polarization selectivity. Other device designs, however, can also be combined with substrate misorientation to strengthen polarization selectivity.
    Type: Grant
    Filed: August 20, 2001
    Date of Patent: January 9, 2007
    Assignee: Xerox Corporation
    Inventors: Christopher L. Chua, Robert L. Thornton, David W. Treat
  • Patent number: 7158548
    Abstract: A laser cavity comprising a gain medium and first and second end mirrors, wherein the laser cavity further comprises a birefringent material and a mirror arranged to fold light propagating within the laser cavity through a predetermined angle, wherein the predetermined angle is selected such that the reflectivity of the fold mirror is polarisation dependent, and the birefringence of the birefringent material co-operates with the polarisation dependent reflectivity of the fold mirror to form a Lyott filter which suppresses oscillation of unwanted laser modes. The invention allows the construction of a low loss, high finesse laser cavity with longitudinal mode control. The need for introduction of an extra polarisation selection element to form a Lyott filter is removed.
    Type: Grant
    Filed: October 29, 2002
    Date of Patent: January 2, 2007
    Assignee: Laser Quantum Ltd.
    Inventors: Alan Cox, Lawrie Gloster, Steve Lane
  • Patent number: 7157298
    Abstract: A method of fabricating a surface emitting semiconductor laser includes the following steps. A first laminate of semiconductor layers and a second laminate of semiconductor layers are formed on a substrate. The first laminate includes a first reflection mirror layer of a first conduction type, an active region, a III-V semiconductor layer containing Al, and a second reflection mirror layer of a second conduction type, the second laminate being used for monitoring and having an oxidizable region. The first and second laminates are etched so as to form mesas on the substrate in which side surface of the III-V semiconductor layer contained in the first laminate is exposed. Oxidization of the III-V semiconductor layer from the side surface is started at an oxidization rate.
    Type: Grant
    Filed: March 11, 2003
    Date of Patent: January 2, 2007
    Assignee: Fuji Xerox Co., Ltd.
    Inventors: Hideo Nakayama, Akira Sakamoto
  • Patent number: 7154920
    Abstract: There is provided a broadly tunable laser beam generator serving as a laser beam source which utilizes a nonlinear optical effect of a silica (glass) fiber and which is broadly tunable in the near-infrared region, having ultra-broad tunability which has not been easily achieved by known tunable lasers, and generating coherent light which can be continuously swept over the entire wavelength region with a simple mechanical operation of a single wavelength selecting element and which is emitted in a constant direction independent of its wavelength. The laser beam source which utilizes a nonlinear optical effect of a silica optical fiber (8) and which is broadly tunable in the near-infrared region has ultra-broad tunability and generates coherent light which can be continuously swept over the entire wavelength region with a single wavelength selecting element (10).
    Type: Grant
    Filed: July 31, 2002
    Date of Patent: December 26, 2006
    Assignee: Japan Science and Technology Agency
    Inventor: Susumu Fukatsu
  • Patent number: 7151785
    Abstract: The invention includes both devices and methods of production. A device in accordance with the invention includes a top surface and a bottom surface, a through wafer via extending from the top surface to the bottom surface, an optoelectronic structure and an ion implanted isolation moat, wherein the optoelectronic structure and the through wafer via are enclosed within the isolation moat. A method in accordance with the invention is a method of producing a device that includes the steps of forming an optoelectronic structure, forming a through wafer via, extending from a top surface to a bottom surface of the device and forming an ion implanted isolation moat, wherein the through wafer via and the optoelectronic structure are enclosed by the isolation moat.
    Type: Grant
    Filed: September 24, 2003
    Date of Patent: December 19, 2006
    Assignee: Finisar Corporation
    Inventors: Yue Liu, Klein L. Johnson, Steven M. Baier
  • Patent number: 7149231
    Abstract: A monolithic, side pumped, passively Q-switched, solid-state laser (10) includes a laser resonator structure (16) that includes a laser gain medium (12) having an output face bonded to a passive Q-switch (14). The gain medium (12) has a side face (12A) for receiving pump light. The pump light is preferably generated by a laser diode array (20). In a further embodiment, a non-linear optical material (22), such as frequency doubling KTP, is optically coupled to an output face of the Q-switch for providing output wavelength conversion. A method is also disclosed for fabricating the monolithic, side pumped, passively Q-switched, solid-state laser. Techniques are included for providing compensation from thermal aberrations during operation of the laser.
    Type: Grant
    Filed: October 3, 2003
    Date of Patent: December 12, 2006
    Assignee: Spectra Systems Corporation
    Inventors: Robert S. Afzal, Andrei Smuk
  • Patent number: 7149237
    Abstract: A laser oscillator capable of preventing contamination of optical components by organic matter such as oil mist. Gas laser medium in an optical resonator constituted by optical components is pumped by an electric discharge generated in an electric discharge tube to produce a laser beam. The gas medium flows at high speed in the electric discharge tube incorporated in a circulating path including a blower. A part of lubrication oil of the blower is evaporated and mixed into the gas medium. Since the optical components are cooled by retaining mechanisms to prevent temperature rise of the components and a gas stagnation occurs between the optical component and the electric discharge tube, the evaporated oil mist tends to be congealed and adhered to a surface of the optical component. A photocatalyst arranged in the vicinity of the optical component effectively decomposes and removes the oil mist.
    Type: Grant
    Filed: February 25, 2003
    Date of Patent: December 12, 2006
    Assignee: Fanuc Ltd
    Inventors: Akira Egawa, Minoru Ando, Takeshi Watanabe
  • Patent number: 7145929
    Abstract: A driver circuit and a method drive an electronic component such as a laser diode with a variable electric current that is controlledly switched between at least two discrete current levels. The driver circuit includes circuit elements that damp ringing or initial transient oscillations that arise when switching the current between the current levels. The driver circuit includes a current mirror having a mirror amplification factor dependent on the frequency of the variable electric current. In order to counteract parasitic capacitances and/or inductances leading to the ringing, an inductance and/or a resistance are connected between the two series circuits making up the current mirror, a capacitance is connected parallel to a reference resistor of one of the series circuits, and/or a capacitance is connected across the voltage supply.
    Type: Grant
    Filed: May 13, 2004
    Date of Patent: December 5, 2006
    Assignee: Atmel Germany GmbH
    Inventors: Guenther Bergmann, Erwin Dotzauer, Holger Vogelmann, Herbert Knotz, Wolfgang Wernig
  • Patent number: 7142569
    Abstract: A tunable laser source includes a gain chip, a collimating lens, a grating, a focusing lens and a wavelength selection device. The grating is positioned to be impinged by the collimated light to provide diffracted beams at different diffraction angles whose wavelengths disperse in accordance with the diffraction angles. Those diffracted beams are then brought to separate focal points on the wavelength selection device through the focusing lens. The wavelength selection device includes a light shield with a single slit formed thereon and a mirror. The single silt allows the mirror to reflect only one diffracted beam back to the gain chip so as to maintain the oscillation of the tunable laser source at the wavelength corresponding to the diffraction angle of the only one focused diffracted beam.
    Type: Grant
    Filed: April 6, 2004
    Date of Patent: November 28, 2006
    Assignee: Delta Electronics, Inc.
    Inventors: Sean Chang, Chia-chi Wu
  • Patent number: 7142574
    Abstract: Described is a laser driver circuit to generate a bias current based, at least in part, upon a reference average power signal and a measured average power signal, and to generate a modulation current based, at least in part, upon a reference swing power and a measured swing power signal.
    Type: Grant
    Filed: May 21, 2003
    Date of Patent: November 28, 2006
    Assignee: Intel Corporation
    Inventors: Bhushan S. Asuri, Ty Yoon
  • Patent number: 7139298
    Abstract: The present invention aims to provide a semiconductor laser device which has a structure that is easy to manufacture, a satisfactory temperature characteristic as well as high-speed response characteristic. The device includes the following: an n-type GaAs substrate 101; an n-type AlGaInP cladding layer 102 formed on the n-type GaAs substrate 101; a non-doped quantum well active layer 103; a p-type AlGaInP first cladding layer 104; a p-type GaInP etching stop layer 105; a p-type AlGaInP second cladding layer 106; a p-type GaInP cap layer 107; a p-type GaAs contact layer 108; and an n-type AlInP block layer 109. The device has a ridge portion and convex portions formed on both sides of the ridge portion, and the p-type GaAs contact layer 108 is formed on the ridge portion only.
    Type: Grant
    Filed: November 23, 2004
    Date of Patent: November 21, 2006
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Kouji Makita, Kenji Yoshikawa, Takayuki Kashima, Hideto Adachi
  • Patent number: 7139299
    Abstract: A semiconductor laser that includes a feedback laser section and an amplifier section. The feedback laser section generates a laser beam that has a maximum intensity at a first wavelength. The amplifier section amplifies the laser beam into a high powered beam. The amplifier section is constructed to have a peak optical gain located at a second wavelength that is offset from the first wavelength. Offsetting the wavelength generated in the feedback laser section from the peak gain wavelength of the amplifier section will result in an output beam that has a much broader linewidth that the feedback section alone. The broader linewidth is relatively stable even when part of the light reflects back into the semiconductor laser.
    Type: Grant
    Filed: February 28, 2003
    Date of Patent: November 21, 2006
    Assignee: Quintessence Photonics Corporation
    Inventor: Jeffrey E. Ungar
  • Patent number: 7133431
    Abstract: A semiconductor laser device includes a substrate which is made of, e.g., silicon and which has in its principal surface first and second recessed portions formed at a distance from each other. Disposed in the first recessed portion is a first semiconductor laser chip in the form of a function block, which emits an infrared laser beam. Disposed in the second recessed portion is a second semiconductor laser chip in the form of a function block, which emits a red laser beam.
    Type: Grant
    Filed: July 30, 2003
    Date of Patent: November 7, 2006
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Kazutoshi Onozawa, Tetsuzo Ueda, Daisuke Ueda
  • Patent number: 7133427
    Abstract: A spatial filter adapted to increase the angular spread of non-conjugated energy in a beam and suppress this energy to improve the efficiency of a phase conjugate system. In the illustrative embodiment, the filter includes first and second lenses and an aberrator to increase the angular spread. In the specific embodiment, an opaque plate, with a pinhole aperture therethrough, is sandwiched between the lenses to suppress the non-conjugated energy. The aberrator may be implemented with an amplifier or other suitable mechanism. Likewise, the aperture may be replaced with a highly angle-selective thick Bragg grating or other suitable arrangement. A phase conjugate master oscillator/power amplifier laser architecture is also disclosed.
    Type: Grant
    Filed: September 19, 2003
    Date of Patent: November 7, 2006
    Assignee: Raytheon Company
    Inventors: Alexander A. Betin, Robin A. Reeder, Robert W. Byren