Patents Examined by Robert E. Wise
  • Patent number: 5828686
    Abstract: A new cartridge excimer laser system and method for generating an excimer laser beam using the system are provided. The system utilizes a cartridge (10) which contains a halogen-noble gas mixture (19), electrodes (50, 60) having external electrical connections (30, 40), and assembly (20) for transmitting a laser beam output (400), and an external gas port (90). The cartridge (10) fits onto a receptacle (100) located within a receiving compartment (200) of the laser base (300) of the new system. The cartridge (10) is easily replaced by the system operator and is refurbished by the manufacturer when the gas mixture (19) therein is exhausted.
    Type: Grant
    Filed: January 14, 1997
    Date of Patent: October 27, 1998
    Assignee: Autonomous Technologies Inc.
    Inventors: Rudolph W. Frey, Philip D. Bolen
  • Patent number: 5825798
    Abstract: The present invention relates to a laser oscillating apparatus using a semiconductor laser or the like and a method of driving a laser beam source. The present invention relates particularly to a laser oscillating apparatus or the like having a nonlinear optical medium for generating a second harmonic and capable of by-pulse driving a laser beam source with high efficiency. In the laser oscillating apparatus, a optical resonator is composed of at least a laser crystal and an output mirror. The nonlinear optical medium for generating the second harmonic is inserted into the optical resonator. The laser beam source can effect pumping on the optical resonator so that the period T of a drive pulse produced from a pulse driving means satisfies a relation in .tau..sub.FL >T-.tau. with respect to .tau..sub.FL (fluorescence lifetime).
    Type: Grant
    Filed: May 20, 1996
    Date of Patent: October 20, 1998
    Assignee: Kabushiki Kaisha Topcon
    Inventors: Masayuki Momiuchi, Hiroshi Koizumi, Masahiro Ohishi, Yoshiaki Goto, Fumio Ohtomo
  • Patent number: 5825790
    Abstract: A gain medium is comprised of a multi-phase system wherein: a first phase is an electromagnetic radiation emission phase; a second phase is an electromagnetic radiation scattering phase; and a third phase is a transparent matrix phase. By example, the emission phase may consist of dye molecules, the scattering phase may consist of high contrast particles, and the matrix phase may consist of a solvent such as methanol. In some embodiments of this invention the emission and scattering phases may be the same phase, as when semiconductor particles are employed. A smallest dimension of a body comprised of the gain medium may be less than a scattering length associated with the scattering phase. It is shown that nearly thresholdless laser behavior is observed in strongly scattering optically pumped dye-methanol solutions containing colloidal TiO.sub.2 or Al.sub.2 O.sub.3 ruby nanoparticles.
    Type: Grant
    Filed: November 12, 1996
    Date of Patent: October 20, 1998
    Assignee: Brown University Research Foundation
    Inventor: Nabil M. Lawandy
  • Patent number: 5825802
    Abstract: An optical element providing greater conversion efficiency and comprising a pyramid having a square base and four triangular faces of equal size and shape meeting at the apex. The optical element can also comprise an octahedron or double pyramid of similar configuration.
    Type: Grant
    Filed: August 23, 1993
    Date of Patent: October 20, 1998
    Inventors: Robin K. Elkins, Martin Bottomley Grier
  • Patent number: 5822346
    Abstract: In response to the output of an operational amplifier, a CPU sets via an R-D/A converter an R-constant current circuit for supplying a read power current Ir to a semiconductor laser thereby driving it, and also sets via a W0-D/A converter an W0-constant current circuit for supplying a first write power current Iw0 to the semiconductor laser thereby driving it. The output of the W0-D/A converter is applied to two voltage-controlled amplifiers so that W1-constant current circuit and W2-constant current circuit provide second and third write power currents Iw1 and Iw2, respectively, to the semiconductor laser in accordance with the outputs of the respective voltage-controlled amplifiers. The gains of these two voltage-controlled amplifiers are set by the CPU such that the gains corresponds to the ratios of Iw1 and Iw2 relative to Iw0.
    Type: Grant
    Filed: January 22, 1997
    Date of Patent: October 13, 1998
    Assignee: Olympus Optical Co., Ltd.
    Inventor: Kazuma Arai
  • Patent number: 5822344
    Abstract: A gas laser is excited by means of a high voltage discharge, at least one firing pulse being applied to a gas discharge tube. The firing pulse can be initiated by a release signal which is applied to an electronic firing unit. Firing pulses then applied to the gas discharge tube until a check-back signal concerning the successful firing of the gas discharge tube is supplied to the electronic firing unit by a detector unit which monitors the operating state of the gas discharge tube.
    Type: Grant
    Filed: October 27, 1995
    Date of Patent: October 13, 1998
    Assignee: Carl-Zeiss-Stiftung
    Inventors: Ralf Benninger, Oliver Rompp
  • Patent number: 5815523
    Abstract: A variable power laser device includes a lasing medium having first and second end faces disposed parallel to one another, N side faces extending between the first and second end faces and a bevel face located at an intersection between the second end and one of the side faces, a first mirror separate from the first end face for directing a laser beam into the lasing medium so as to permit the laser beam to follow a helical transmission path defined by the N side faces, the transmission path being longer than the length of any of the N side faces, and a second mirror separate from the second end face for receiving an amplified laser beam output by the lasing medium and reflecting the amplified laser beam in a predetermined direction, wherein N is an integer greater than or equal to 3. The output power of the amplified laser beam is dependent on the number of loops in the transmission path.
    Type: Grant
    Filed: November 27, 1996
    Date of Patent: September 29, 1998
    Assignee: McDonnell Douglas Corporation
    Inventor: Henry B. Morris
  • Patent number: 5815610
    Abstract: A system comprises a substrate 4, an incident optical waveguide 5 formed on the substrate for receiving a light beam incident thereto, two phase-shift optical waveguides 6 formed on the substrate 4 to be branched from the incident optical waveguide 4 for varying a phase of a transmitted light beam in response to an electric field intensity, an outgoing optical waveguide 7 formed on the substrate 4 to join the phase-shift optical waveguides 6. At least one of the phase-shift optical waveguides 6 has a reversely polarized portion 8 reversely polarized. A light transmission film may be formed at one or a plurality of portions on the phase-shift optical waveguides 6. A buffer layer 14 may be formed on a part on or in the vicinity of the phase-shift optical waveguides 6. A transparent substance film for imparting a stress to one of the phase-shift optical waveguides 6 may be formed on a part or a whole of a portion without the buffer layer 14.
    Type: Grant
    Filed: March 3, 1997
    Date of Patent: September 29, 1998
    Assignee: Tokin Corporation
    Inventors: Yuichi Tokano, Ryoji Muramatsu, Takanobu Tanabe, Tsugio Takeda
  • Patent number: 5809049
    Abstract: The present invention monitors the RF drive circuitry of a linear laser transmitter. In one preferred embodiment of the present invention, a filtered RF signal from the monitor diode is amplified and then input to a peak detector. The output of the peak detector is then fed to the input of a threshold detector, wherein the threshold detector determines whether the output of the peak detector is above a predetermined threshold. If the output of the peak detector falls below the predetermined threshold an alarm is generated at the status monitoring ports of the laser transmitter.
    Type: Grant
    Filed: December 19, 1996
    Date of Patent: September 15, 1998
    Assignee: Lucent Technologies Inc.
    Inventors: Mark Steven Schaefer, David B. Winick
  • Patent number: 5805631
    Abstract: A laser for outputting visible light at the wavelengths of blue, green, orange and red light. This is accomplished through the doping of a substrate, such as an optical fiber or waveguide, with Pr.sup.3+ ions and Yb.sup.3+ ions. A light pump such as a diode laser is used to excite these ions into energy states which will produce lasing at the desired wavelengths. Tuning elements such as prisms and gratings can be employed to select desired wavelengths for output.
    Type: Grant
    Filed: July 26, 1996
    Date of Patent: September 8, 1998
    Assignee: The Regents of the University of California
    Inventors: Ping Xie, Timothy R. Gosnell
  • Patent number: 5802087
    Abstract: To prevent a power supply from being covered with dew for circuit protection and to downsize or simplify a laser apparatus: An excitation lamp 10 and a YAG rod (laser medium) 12 of a laser oscillator are disposed within a chamber 14. Heat-generating electrical components or elements of the power supply, such as diodes D1-D6 of a three-phase full-wave rectifier circuit 24, IGBT 26, GTR 30 and output transistors of driver circuits 34 and 36 are mounted on a heat sink 46. A water-cooled cooling apparatus 50 supplies deionized water (cooling water) DW whose temperature is controlled at a predetermined temperature, for instance, 25-35 degrees centigrade to the heat sink 46 of the power supply via pipes 72 and 76 as well as the chamber 14 of the laser oscillator via pipes 70 and 74.
    Type: Grant
    Filed: January 11, 1996
    Date of Patent: September 1, 1998
    Assignee: Miyachi Technos Corporation
    Inventor: Kohji Takaichi
  • Patent number: 5802084
    Abstract: The mode-locked laser with improved pulse power output can be realized by combining an optical oscillator with a flared CW or modulated gain amplifier. An optical filter or isolator may be disposed between the oscillator and amplifier to avoid feedback of spontaneous noise. A two-segment laser is devised by providing a flared gain section between a modulated gain section and an absorber section within the integrated semiconductor laser. The flared section may taper from a larger modulated gain section to a smaller cross section absorber section or vice versa. Various combinations of absorber sections coupled to modulated gain sections by CW gain or passive flared gain sections may be combined with various arrangements of reflectors and tapered CW gain amplifiers are cascades of such amplifiers and modulated gain pairs.
    Type: Grant
    Filed: November 14, 1994
    Date of Patent: September 1, 1998
    Assignee: The Regents of the University of California
    Inventors: John E. Bowers, Alan Mar, Roger J. Helkey, Judy Karin
  • Patent number: 5802086
    Abstract: A composite cavity continuous wave (cw) microlaser that lases at two fundamental wavelengths, denoted by .lambda..sub.1 and .lambda..sub.2, which are frequency-mixed in a suitable nonlinear crystal oriented within an optically resonant cavity for phase-matched frequency mixing to generate radiation at a third wavelength. The optically resonant cavity is defined by a first reflective surface and a second reflective surface, both of which are substantially reflective at a first and a second wavelength. A highly absorbing solid-state gain material, preferably Nd:YVO.sub.4, which has a first gain transition at the first wavelength and a second gain transition at the second wavelength different from the first wavelength is disposed within the optically resonant cavity. The highly absorbing solid-state gain material is closely coupled to the first reflective surface to promote single mode operation of both fundamental lasing frequencies.
    Type: Grant
    Filed: January 29, 1996
    Date of Patent: September 1, 1998
    Assignee: Laser Power Corporation
    Inventors: David E. Hargis, Maurice A. Pessot
  • Patent number: 5802085
    Abstract: This invention relates to a singlemode laser source tunable in wavelength with a self-aligned external cavity, comprising: a resonant cavity having an output face that is partially reflecting (331) and a retroreflecting dispersive device (31, 39), defining a main collimating axis (351) and a secondary collimating axis (381), an amplifier wave guide (33) placed in position inside the resonant cavity. The retroreflecting dispersive device comprises a plane diffraction grating (31) having dispersion planes and an orthogonal reflecting dihedral (39) whose line of intersection (391) is parallel to the dispersion plane of the diffraction grating containing the collimating axes (351, 352).
    Type: Grant
    Filed: November 13, 1996
    Date of Patent: September 1, 1998
    Assignee: Photonetics S.A.
    Inventors: Herve Lefevre, Philippe Martin, Bernard LaLoux, Philippe Graindorge, Laurent Disdier
  • Patent number: 5802093
    Abstract: A continuous wave photolytic iodine laser has a gain cell for receiving a continuous supply of gaseous fuel. The gain cell is connected to laser beam transfer optics, a laser resonator for shaping a laser beam, and a lamp. The lamp is driven by a microwave subsystem such that a laser gain medium is pumped through the gain cell. The continuous wave photolytic iodine laser of the present invention incorporates a closed loop fuel system for presenting gaseous fuel to the gain cell at a rate sufficient to sweep any lasing by-products out of the gain cell, thereby preventing quenching of the lasing process. The fuel system also includes a condenser for converting the gaseous fuel to a liquid after it has passed through the gain cell, a scrubber for removing the by-products of the lasing process from the fuel, and an evaporator for converting the recycled liquefied fuel back to a gas. The closed loop fuel system also includes a pump for pressurizing and transporting the liquefied fuel.
    Type: Grant
    Filed: May 22, 1996
    Date of Patent: September 1, 1998
    Inventors: Sallie S. Townsend, Philip R. Cunningham
  • Patent number: 5799029
    Abstract: A laser system is provided for supplying high power, stable light intensity via an aperture limited delivery system to an application requiring continuous light output intensity in spite of the laser source being subjected optical feedback noise caused by external system and delivery system perturbations that cause fluctuation in laser source power intensity. Non-stable light intensity in the output is due to environmental temperature changes, and phase and amplitude changes caused by system induced perturbations such as by movement of the aperture limited delivery system and optical artifacts of the optical elements, comprising the aperture limited delivery system, introducing noise into the feedback in the laser system changing the output intensity pattern of the delivered power beam. This can be substantially remedied by the employing a monolithic, multiple, independent single mode laser source which is substantially unaffected by this noise.
    Type: Grant
    Filed: May 14, 1996
    Date of Patent: August 25, 1998
    Assignee: SDL, Inc.
    Inventors: David M. Rossi, Harrison L. Ransom, Jr.
  • Patent number: 5799031
    Abstract: The gas mixture leaving the laser apparatus (1) is recycled to a permeator (45) which separates it into two flows. The discharge from the permeator is expanded in an expansion turbine (27) coupled to a compressor (35) for exerting suction on the recycled mixture, which makes it possible to obtain the desired reduced pressure in the laser apparatus. Applications to power laser apparatuses with nitrogen/carbon dioxide mixture, intended for cutting materials.
    Type: Grant
    Filed: January 26, 1996
    Date of Patent: August 25, 1998
    Assignee: L'Air Liquide, Societe Anonyme pour l'Etude et l'Exploitation des Procedes Georges Claude
    Inventors: Bruno Marie, Daniel Guerin, Christian Larquet, Antoine Willemot
  • Patent number: 5799025
    Abstract: A self starting, self mode-locked laser is disclosed that utilizea gain saturation lens and an optical Kerr lens to start and to sustain passive mode locking. The laser consists of a resonant cavity which has a saturable gain medium and an optical Kerr lens medium. The laser cavity is described such that the loss modulation induced by the gain saturation lens is cascaded to that of the optical Kerr lens to start the mode locking process, while the loss modulation of the Kerr lens maintains the mode locking. The self mode locking operation restores automatically without any additional induction mechanism, after the pump laser beam or the laser cavity is blocked and then unblocked. In a preferred embodiment, the laser includes a resonant cavity , a Ti:sapphire crystal which produces both the gain saturation lens and the optical Kerr lens, a prism pair for ultra-short pulse operation, and a slit for laser bandwidth control and wavelength tuning. This laser can produce stable pulses shorter than 100 femtosecond.
    Type: Grant
    Filed: March 27, 1997
    Date of Patent: August 25, 1998
    Assignee: Novatic Laser Systems, Inc.
    Inventors: Ming Lai, Shui T. Lai
  • Patent number: 5799024
    Abstract: The mode-locked laser with improved pulse power output can be realized by combining an optical oscillator with a flared CW or modulated gain amplifier. An optical filter or isolator may be disposed between the oscillator and amplifier to avoid feedback of spontaneous noise. A two-segment laser is devised by providing a flared gain section between a modulated gain section and an absorber section within the integrated semiconductor laser. The flared section may taper from a larger modulated gain section to a smaller cross section absorber section or vice versa. Various combinations of absorber sections coupled to modulated gain sections by CW gain or passive flared gain sections may be combined with various arrangements of reflectors and tapered CW gain amplifiers are cascades of such amplifiers and modulated gain pairs.
    Type: Grant
    Filed: December 19, 1996
    Date of Patent: August 25, 1998
    Assignee: The Regents of the University of California
    Inventors: John E. Bowers, Alan Mar, Roger J. Helkey, Judy Karin
  • Patent number: 5796767
    Abstract: A driver circuit of a light-emitting device that is able to reduce the current consumption. This circuit includes a reference current source for generating a reference current, a cascode current source circuit for generating a driving current for the light-emitting device with the use of the reference current, and an input circuit for switching the driving current according to a data signal. The cascode current source circuit has a first current mirror formed by first and second transistors and a second current mirror formed by third and fourth transistors. The first transistor is supplied with a first constant current proportional to the reference current, and controls the second transistor so that the driving current flows through the second transistor. The third transistor is supplied with a second constant current proportional to the reference current, and generates a mirror current with respect to the second constant current.
    Type: Grant
    Filed: February 20, 1997
    Date of Patent: August 18, 1998
    Assignee: NEC Corporation
    Inventor: Yukio Aizawa