Patents Examined by Delma R. Flores-Ruiz
  • Patent number: 7420998
    Abstract: A semiconductor laser device has a front surface electrode formed by Au plating, a rear surface electrode formed by Au plating, an anti-adhesive film only on the front surface electrode and made of a material that does not react with Au, and a coating film that covers an end face on a light emitting side and an end face opposite the light emitting side. The anti-adhesive films are located on the four corners of the front surface electrode.
    Type: Grant
    Filed: March 23, 2005
    Date of Patent: September 2, 2008
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventor: Junichi Horie
  • Patent number: 7369591
    Abstract: A driver for a vertical-cavity surface emitting laser (VCSEL) is provided that includes a bias current source, a modulation source, and a peaking control circuit. The bias current source is operable to generate a bias current for the VCSEL and an output voltage. The modulation current source is coupled to the bias current source by at least one switch and is operable to generate a modulation current for the VCSEL when the switch is closed. The peaking control circuit is coupled to the bias current source. The peaking control circuit is operable to receive the output voltage from the bias current source and to generate a driver output voltage for the VCSEL based on the output voltage. The driver output voltage has less peaking than the output voltage.
    Type: Grant
    Filed: January 14, 2005
    Date of Patent: May 6, 2008
    Assignee: National Semiconductor Corporation
    Inventor: Ramsin M. Ziazadeh
  • Patent number: 7362784
    Abstract: An object of the present invention is obtaining a semiconductor film with uniform characteristics by improving irradiation variations of the semiconductor film. The irradiation variations are generated due to scanning while irradiating with a linear laser beam of the pulse emission. At a laser crystallization step of irradiating a semiconductor film with a laser light, a continuous light emission excimer laser emission device is used as a laser light source. For example, in a method of fabricating an active matrix type liquid crystal display device, a continuous light emission excimer laser beam is irradiated to a semiconductor film, which is processed to be a linear shape, while scanning in a vertical direction to the linear direction. Therefore, more uniform crystallization can be performed because irradiation marks can be avoided by a conventional pulse laser.
    Type: Grant
    Filed: August 15, 2006
    Date of Patent: April 22, 2008
    Assignee: Semiconductor Energy Laboratory Co., Ltd.
    Inventors: Shunpei Yamazaki, Koichiro Tanaka
  • Patent number: 7359414
    Abstract: A semiconductor laser light emitting circuit includes a semiconductor laser diode emitting a laser light by modulating a current supplied thereto, a light intensity detection circuit that detects the laser light and generates a voltage, and a voltage-current conversion circuit converting a voltage into a current supplied to the laser diode. A S/H capacitance is provided to store electric charge and output a voltage to the voltage/current conversion circuit. A first operational amplifier is provided to output a first current charging the S/H capacitance. A rapidly charging circuit is provided to charge the S/H capacitance with a second current. The rapidly charging circuit terminates charging when the voltage is equal to or more than a second reference voltage.
    Type: Grant
    Filed: October 25, 2004
    Date of Patent: April 15, 2008
    Assignee: Ricoh Company, Ltd.
    Inventors: Junichi Ikeda, Hiroaki Kyougoku
  • Patent number: 7352786
    Abstract: In case of driving each of light emitting parts of a surface emitting laser, each of light emitting parts is made to be in forward-bias state and switches appropriately change bias voltage, which is lower than laser oscillation threshold voltage, and drive voltages, which are not less than the laser oscillation threshold voltage to directly apply the changed voltage to each of drive ends of the light emitting parts. Whereby, each of light emitting parts is driven.
    Type: Grant
    Filed: March 5, 2002
    Date of Patent: April 1, 2008
    Assignee: Fuji Xerox Co., Ltd.
    Inventor: Chikaho Ikeda
  • Patent number: 7321606
    Abstract: A method includes a scheme for trimming and compensation for a laser emitter in a fiber optic link. Data models of laser performance are provided and used to determine a base power level. It is then confirmed that the base power level is satisfactory. If necessary, adjustments are made to a set of user specified performance parameters until a satisfactory base power level is obtained. Then a table or relation of temperatures and associated current and target average optical power values is generated such that they can be used to regulate laser emitter performance over a range of temperature. Additionally, fiber optic links capable of trimming and compensation are also disclosed.
    Type: Grant
    Filed: December 9, 2003
    Date of Patent: January 22, 2008
    Assignee: National Semiconductor Corporation
    Inventors: Hsin-Ho Wu, Peter Deane
  • Patent number: 7310359
    Abstract: Aspects of the present invention are directed to the use of optical gain structures that include alternating layers of gain medium and transparent heat conductors in which the gain medium itself functions as a correction optic. The gain medium changes to an optimum or desired shape because of the thermal changes occurring as the materials of the optical gain structure(s) reach a desired optical output condition. At the desired optical output conditions, the gain medium conforms to a desired shape. The desired shape may be, for example, that of an optical surface of a transparent heat conductor. By designing the initial shape of the gain medium such that the physical contact with the transparent heat conductor is maximized at the desired optical output conditions, conductive heat transfer between the gain medium and heat conductor(s) is maximized at the desired optical output condition.
    Type: Grant
    Filed: December 1, 2004
    Date of Patent: December 18, 2007
    Assignee: Textron Systems Corporation
    Inventors: Hsian P. Chou, Yu-Lin Wang
  • Patent number: 7295589
    Abstract: A frequency modulated (FM) vertical cavity surface emitting laser (VCSEL). The frequency modulated VCSEL includes a mirror region that has an active region. The frequency modulated VCSEL also includes a phase adjustment region for use in altering the characteristics of the VCSEL. For example, by changing the index of refraction in the phase adjustment region, the wavelength of the VCSEL can be changed, resulting in frequency modulation.
    Type: Grant
    Filed: February 15, 2003
    Date of Patent: November 13, 2007
    Assignee: Avago Technologies Fiber (Singapore) Pte Ltd
    Inventors: Frank H. Peters, Ken A. Nishimura, Jonathan Simon, Kirk S. Giboney
  • Patent number: 7289544
    Abstract: The object of the present invention is to provide an optical module for the WDM communication system, in which the oscillation wavelength is on the grid of the WDM regulation, moreover the optical output power and the oscillation wavelength can be controlled independently. The present module comprises a semiconductor light-emitting device, a wedge shaped etalon device and two light-receiving devices. The etalon device contains a first portion, on which the anti-reflection films are coated, and a second portion. One of the receiving devices detects light transmitted through the first portion of the etalon device, while the other device detects light through the second portion. Signal from the former device controls the output power of the light-emitting device, while the signal from the latter receiving device controls the oscillation wavelength of the laser.
    Type: Grant
    Filed: November 19, 2004
    Date of Patent: October 30, 2007
    Assignee: Sumitomo Electric Industries, Ltd.
    Inventors: Jiro Shinkai, Takashi Kato, Toshio Takagi, Hiroyuki Yabe
  • Patent number: 7248608
    Abstract: An improved monoblock laser cavity is made by elongating the Optical parametric oscillation (OPO) cavity. This can be accomplished by changing the coatings on the OPO material and Q-switch and by elongating the OPO cavity to approximately 2 to 3 times the OPO crystal length. The increase in the length of the OPO cavity will improve the beam divergence of the laser.
    Type: Grant
    Filed: October 28, 2004
    Date of Patent: July 24, 2007
    Assignee: United States of America as represented by the Department of the Army
    Inventor: John E. Nettleton
  • Patent number: 7236504
    Abstract: A method of operating a stretched-pulse Raman fiber laser includes producing laser radiation gain in a laser cavity using predominantly Raman amplification. Such a stretched-pulse Raman fiber laser has a laser cavity that includes a Negative Group Velocity Dispersion Fiber connected in series with a Positive Group Velocity Dispersion Fiber, a polarization controller and an isolator. In some examples, the Negative Group Velocity Dispersion Fiber is a Dispersion Compensating Fiber. In other examples, the Negative Group Velocity Dispersion Fiber is replaced by a Raman Specialty Fiber.
    Type: Grant
    Filed: January 7, 2005
    Date of Patent: June 26, 2007
    Assignee: General Instrument Corporation
    Inventor: Shamino Y. Wang
  • Patent number: 7218649
    Abstract: A laser beam containment system includes a number of optics that direct a laser beam produced by a laser beam source along a path to a point of application of the laser beam. One or more hollow tubes are positioned in an arrangement such that the laser beam passes through the hollow tubes. The hollow tubes are also adjustably positioned relative to the laser beam objects to allow for access to the optics for maintenance and adjustment of the optics. Locking mechanisms provide control of the adjustment features of the containment tubes.
    Type: Grant
    Filed: August 28, 2003
    Date of Patent: May 15, 2007
    Assignee: Philip Morris USA Inc.
    Inventors: Loren Duvekot, Marc D. Belcastro
  • Patent number: 7215693
    Abstract: A surface emitting semiconductor laser device including a substrate, a bottom DBR, and a mesa post having a layer structure, the layer structure including a top DBR including a plurality of pairs, each of said pairs including an Al-containing high-reflectivity layer and an Al-containing low-reflectivity layer, an active layer structure sandwiched between the DBRs for emitting laser, and a current confinement layer disposed within or in a vicinity of one of the DBRs, the current confinement layer including a central current injection area and an annular current blocking area encircling the central current injection area, the annular current blocking area being formed by selective oxidation of Al in an AlXGa1-XAs layer (0.95?x<1) having a thickness below 60 nm, the Al-containing low-reflectivity layer including Al at an atomic ratio not more than 0.8 and below 0.9.
    Type: Grant
    Filed: July 27, 2004
    Date of Patent: May 8, 2007
    Assignee: The Furukawa Electric Co., Ltd.
    Inventors: Norihiro Iwai, Tatsuyuki Shinagawa, Noriyuki Yokouchi
  • Patent number: 7212559
    Abstract: An optical resonator includes a first substrate and a second substrate which face each other, the first substrate having a flat main surface on which a first reflective mirror is provided and the second substrate having a concave portion on which a second reflective mirror is provided and a flat portion which surrounds the concave portion. The main surface of the first substrate and the flat portion of the second substrate are bondable. In addition, a laser oscillator includes a solid-state laser medium and a substrate, the solid-state laser medium having a main surface on which a first reflective mirror is provided and the substrate having a concave portion on which a second mirror is provided and a flat portion which surrounds the concave portion. The first and the second reflective mirrors serve as a laser resonator.
    Type: Grant
    Filed: February 27, 2004
    Date of Patent: May 1, 2007
    Assignee: Sony Corporation
    Inventors: Kazuya Hayashibe, Masayuki Morita, Tatsuo Fukui, Yutaka Imai
  • Patent number: 7212557
    Abstract: A semiconductor laser device produces a laser beam, which is adapted to be expanded into a linear laser beam for use as stimulating rays for an image read-out operation for reading out a radiation image having been stored on a stimulable phosphor sheet. The semiconductor laser device comprises a semiconductor laser chip for producing the laser beam, a package for accommodating the semiconductor laser chip therein, and a radiating window, which is fitted to the package and allows the laser beam having been produced by the semiconductor laser chip to pass therethrough. A surface of the radiating window is coated with an anti-reflection film having a reflectivity of at most 1.0% with respect to a wavelength of the laser beam having been produced by the semiconductor laser chip.
    Type: Grant
    Filed: August 26, 2004
    Date of Patent: May 1, 2007
    Assignee: Fujifilm Corporation
    Inventor: Katsumi Shimada
  • Patent number: 7212556
    Abstract: A semiconductor laser device includes: a first cladding layer, which is made of a nitride semiconductor of a first conductivity type and is formed over a substrate; an active layer, which is made of another nitride semiconductor and is formed over the first cladding layer; and a second cladding layer, which is made of still another nitride semiconductor of a second conductivity type and is formed over the active layer. A spontaneous-emission-absorbing layer, which is made of yet another nitride semiconductor of the first conductivity type and has such an energy gap as absorbing spontaneous emission that has been radiated from the active layer, is formed between the substrate and the first cladding layer.
    Type: Grant
    Filed: February 15, 2000
    Date of Patent: May 1, 2007
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Masahiro Kume, Isao Kidoguchi, Yuzaburo Ban, Ryoko Miyanaga, Masakatsu Suzuki
  • Patent number: 7203216
    Abstract: Feedback timing control equipment and process for an injection seeded modular gas discharge laser. A preferred embodiment is a system capable of producing high quality pulsed laser beams at pulse rates of about 4,000 Hz or greater and at pulse energies of about 5 to 10 mJ or greater for integrated outputs of about 20 to 40 Watts or greater. The feedback timing control is programmed to permit in some circumstances discharges timed so that no significant laser energy is output from the system. Use of this technique permits burst mode operation in which the first discharge of a burst is a no-output discharge so that timing parameters for each of the two chambers can be monitored before the first laser output pulse of the burst. Two separate discharge chambers are provided, one of which is a part of a master oscillator producing a very narrow band seed beam which is amplified in the second discharge chamber.
    Type: Grant
    Filed: August 20, 2004
    Date of Patent: April 10, 2007
    Assignee: Cymer Inc.
    Inventors: Alexander I. Ershov, Richard M. Ness
  • Patent number: 7194012
    Abstract: Systems and methods for biasing an externally modulated laser. An inductorless bias T network is provided that includes a terminating resistor in series with a capacitor. The capacitor is an open circuit for a bias signal and a virtual ground for an RF signal. Thus, the RF signal is terminated by the terminating resistor without dissipating the bias signal through a ground return path of the RF signal. Using a charge pump inverter, a positive supply can be used to positively bias a laser and negatively bias the external modulator through the terminating resistor. A negative power supply is not required. A swing voltage provided by the RF signal causes the external modulator to modulate the light emitted by the laser.
    Type: Grant
    Filed: November 23, 2004
    Date of Patent: March 20, 2007
    Assignee: Finisar Corporation
    Inventors: T. G. Beck Mason, Dev E. Kumar, Giorgio Giaretta
  • Patent number: 7190706
    Abstract: A laser package includes a submount, a laser die mounted on the submount, a lid mounted on the submount over the laser die, and a soft metal disposed between the laser die and the lid, wherein the soft metal conducts heat between the laser die and the lid. The soft metal is able to creep or cold flow under pressure to accommodate for varying manufacturing tolerances and varying thermal expansion rates of the elements in the laser package.
    Type: Grant
    Filed: December 10, 2003
    Date of Patent: March 13, 2007
    Assignee: Avago Technologies Fiber IP (Singapore) Ptd. Ltd.
    Inventor: Laurence Ray McColloch
  • Patent number: 7190705
    Abstract: Various embodiments include modelocked fiber laser resonators that may be coupled with optical amplifiers. An isolator may separate the laser resonator from the amplifier, although certain embodiments exclude such an isolator. A reflective optical element on one end of the resonator having a relatively low reflectivity may be employed to couple light from the laser resonator to the amplifier. Enhanced pulse-width control may be provided with concatenated sections of both polarization-maintaining and non-polarization-maintaining fibers. Apodized fiber Bragg gratings and integrated fiber polarizers may be also be included in the laser cavity to assist in linearly polarizing the output of the cavity. Very short pulses with a large optical bandwidth may be obtained by matching the dispersion value of the fiber Bragg grating to the inverse of the dispersion of the intra-cavity fiber. Frequency comb sources may be constructed from such modelocked fiber oscillators.
    Type: Grant
    Filed: March 31, 2004
    Date of Patent: March 13, 2007
    Assignee: IMRA America. Inc.
    Inventors: Martin E. Fermann, Donald J. Harter