Specified Output Coupling Device Patents (Class 372/108)
  • Patent number: 5999555
    Abstract: A pulsed solid state laser system is disclosed which utilizes a plurality of individual laser rods which are sequentially pumped and whose beans are combined into a single interleaved output bean. The individual laser rods are pumped at an average power level which is below that for maximum output power from each rod, thereby obviating the need for refrigeration cooling. A compact optical system is disclosed which permits a constant beam size even at different pump levels and other advantages. A compact cooling system is also disclosed.
    Type: Grant
    Filed: June 26, 1998
    Date of Patent: December 7, 1999
    Assignee: Coherent, Inc.
    Inventors: Kevin P. Connors, James L. Hobart, Edward D. Reed, David Trost
  • Patent number: 5991317
    Abstract: A diode pumped, multi axial mode, intracavity doubled, intracavity tripled laser, includes at least two resonator mirrors defining a resonator cavity. A laser crystal and a doubling crystal are positioned in the resonator cavity. A tripling crystal is also positioned in the resonator cavity. A diode pump source supplies a pump beam to the laser crystal and produces a laser crystal beam with a plurality of axial modes that are incident on the doubling crystal. This produces a frequency doubled output beam.Further, a diode pumped, multi axial mode, intracavity nonlinearly-converted laser is provided and includes at least two resonator mirrors defining a resonator cavity, a laser crystal and a nonlinear conversion apparatus positioned in the resonator cavity. A nonlinear conversion apparatus is also positioned in the resonator cavity.
    Type: Grant
    Filed: March 5, 1998
    Date of Patent: November 23, 1999
    Assignee: Spectra Physics Lasers, Inc.
    Inventors: William L. Nighan, Jr., John Cole
  • Patent number: 5987050
    Abstract: A laser transmitter based on a star coupler includes a separate controlled output port. An interferometric modulator is incorporated inside a laser cavity by means of a star coupler and enables modulation of the laser signal, independent of the means of wavelength selection used to determine the frequency of the laser.
    Type: Grant
    Filed: November 16, 1998
    Date of Patent: November 16, 1999
    Assignee: Lucent Technologies, Inc.
    Inventors: Christopher Richard Doerr, Charles H. Joyner
  • Patent number: 5986794
    Abstract: The invention relates to novel laser optics for shaping at least one laser eam which has a linear or strip-shaped cross section which extends in the first axial direction (X-axis) perpendicular to the beam axis (Z-axis), with at least two optical shaping elements which are located in succession in the beam path, and of which at least one is an element through which a laser beam has passed, and which form an optical arrangement, in which at least one laser beam is fanned out in one plane (Y-Z plane) perpendicular to the first axis (X-axis) into several parallel component beams which are offset against one another both in the first axial direction (X-axis) and also in the second axial direction (Y-axis) which is perpendicular to the beam axis (Z-axis) and perpendicular to the first axis (X-axis), and in which then the fanned-out component beams are combined.
    Type: Grant
    Filed: January 30, 1998
    Date of Patent: November 16, 1999
    Assignee: Laserline Gesellschaft Fur Entwicklung und Vertrieb Von Diodenlasern MBH
    Inventors: Volker Krause, Christoph Ullmann
  • Patent number: 5974060
    Abstract: A laser crystal (25) having a relatively short optical length functions as a seed laser (1) and simultaneously establishes the wide separation between longitudinal modes. Pulsed operation causes multiple longitudinal modes to co-exist before competition acts to extinguish modes. The seed laser (1) is isolated from the relatively higher peak power output beam (4). Further, the injection seeded slave resonator (6) optical cavity length is adjusted by mechanical, electromechanical and/or electro-optical component(s) to harmonize the slave resonator optical cavity to the seed laser (1) optical cavity. A number of widely separated longitudinal modes are simultaneously output as a pulsed, high optical quality beam having a broad frequency range, short temporal coherence, and stable simultaneous operation of the several modes.
    Type: Grant
    Filed: January 5, 1999
    Date of Patent: October 26, 1999
    Assignee: Raytheon Company
    Inventors: Robert W. Byren, Robin A. Reeder
  • Patent number: 5966391
    Abstract: A polarization controlled laser system receiving a pump laser beam includes a long laser cavity for precluding mode hopping. Preferably, the long laser cavity is defined by first and second dichroic reflectors, a rare earth doped optical fiber disposed between the first and second dichroic reflectors for amplifying the pump laser beam to thereby produce an amplified laser beam, a polarization controller for controlling polarization of the amplified laser beam, and a polarization selector for selecting the polarization of the amplified laser beam. The polarization selector can include a polarizing optical fiber while the polarization controller advantageously may include a polarization maintaining optical fiber. Alternatively, the rare-earth doped optical fiber, the polarization controller, and the polarization selector are all formed from a single polarizing rare-earth doped optical fiber.
    Type: Grant
    Filed: June 27, 1997
    Date of Patent: October 12, 1999
    Assignee: McDonnell Douglas Corporation
    Inventors: Mark S. Zediker, Robert A. Rice
  • Patent number: 5963684
    Abstract: An optical demultiplexing apparatus is capable of spatially separating a multiplexed optical signal into two or more optical wavelength signals thereof. An input multiplexed optical signal present on a first plane is imaged through a color-selective grating plane to a second plane. The color-selective grating has a nonlinear change of diffraction characteristics as a function of incident wavelength to provide substantial spatial separation in the second plane between bands of wavelengths proximate to the two or more optical wavelength signals. In another embodiment, the apparatus uses a polarization-selective grating to spatially separate a polarization-multiplexed optical signal into two substantial spatially separated optical polarization signals. In other embodiments, the optical apparatus may be used as an optical signal multiplexer, splitter, or combiner.
    Type: Grant
    Filed: February 13, 1997
    Date of Patent: October 5, 1999
    Assignee: Lucent Technologies Inc.
    Inventors: Joseph Earl Ford, Thomas Huntington Wood, James Albert Walker
  • Patent number: 5960025
    Abstract: Disclosed is a mirror mounting device and method for beam path alignment of an optical cavity for a ring laser gyroscope. The ring laser gyroscope is of the type that includes a block having an optical cavity that defines a closed loop optical path. A light source directs a light beam into the path. The block includes mounting surfaces for mirrors that reflect the light beam at the optical path corners. The mirror mounting device is associated with one of the block mounting surfaces and acts to orient a concave reflective surface of one of the mirrors such that the light beam is aligned within the closed loop optical path and is at its maximum intensity irrespective of the position of the concave reflective surface of the mirror relative to its mounting surface.
    Type: Grant
    Filed: October 6, 1997
    Date of Patent: September 28, 1999
    Assignee: Honeywell Inc.
    Inventors: Rodney H. Thorland, Daniel L. Sittler, David W. Carlson, Gerald R. Altmann
  • Patent number: 5953354
    Abstract: A laser resonator includes a laser medium having opposite end faces inclined at Brewster's angle and disposed in optical alignment between spaced-apart and tilted first and second optical elements. A method for adjusting the optical alignment includes pumping the laser medium to produce a laser beam, and adjusting separation spacing between the two optical elements. Tilt of at least one of the optical elements is adjusted in response to any observed change in beam cross-sectional size. In an additional embodiment, the laser medium is initially positioned at about equal spacings between the first and second elements. Position of the laser medium is then adjusted, at a constant value of the separation spacing, to within a position range selected for a specific value of a ratio of intracavity peak power of circulation of the laser beam and a critical power for self-focusing to effect discrimination of mode-locked operation over continuous wave operation.
    Type: Grant
    Filed: February 3, 1998
    Date of Patent: September 14, 1999
    Assignee: General Electric Co.
    Inventors: Phillip Randall Staver, William Taylor Lotshaw
  • Patent number: 5949810
    Abstract: A robust and simple laser guideline system provides a precisely located line image by passing a laser beam through a perpendicularly oriented transparent cylinder. The cylinder may be rotated into or out of the beam providing dual modes of line or dot image projection. A swivel mount is disclosed for use of the laser guideline system on saws or the like to demarcate the cut path.
    Type: Grant
    Filed: November 10, 1997
    Date of Patent: September 7, 1999
    Assignee: Jan A. Strand
    Inventors: Jeffrey H. Star, Sheldon Star
  • Patent number: 5943352
    Abstract: A stable switched multifrequency source is described. The stable switched multifrequency source includes a narrowband reflective optical filter bank. This bank includes a plurality of narrowband reflective optical filter devices. In one embodiment, the stability and precision of the reflectivity of the narrowband reflective optical filter devices is further enhanced through regulation via temperature and/or bias current based on a comparison of the output wavelength and a precise stable wavelength reference. The stable switched multifrequency source also includes an optical switch that is coupled to each of the narrowband reflective optical filter devices.
    Type: Grant
    Filed: March 25, 1997
    Date of Patent: August 24, 1999
    Assignee: MCI Communication Corporation
    Inventor: John Fee
  • Patent number: 5943358
    Abstract: An unstable laser resonator geometry with a gradient reflectivity mirror M) and external lens, or a gradient reflectivity mirror-lens (GRML), achieving a vast improvement in the intrinsic divergence and brightness of the output laser beam.
    Type: Grant
    Filed: July 9, 1997
    Date of Patent: August 24, 1999
    Assignee: The United States of America as represented by the Secretary of the Army
    Inventors: Toomas H. Allik, Suresh Chandra, J. Andrew Hutchinson
  • Patent number: 5936993
    Abstract: In order to improve upon a laser system, comprising a laser-active medium which is arranged between mutually opposed waveguide surfaces of an optical waveguide and a resonator which by means of resonator mirrors defines a coherent resonator radiation field permeating the optical waveguide and from which a plurality of mutually coherent radiation fields issue, in such manner that higher laser output power levels can be attained it is proposed that the plurality of radiation fields are conducted as coupled-out radiation fields to a coupling element, and that the coupling element combines the plurality of radiation fields with a defined mutual phase relationship to form one single coherent output radiation field.
    Type: Grant
    Filed: October 31, 1997
    Date of Patent: August 10, 1999
    Assignee: Deutsche Zentrum Fuer Luft- und Raumfahrt e.V.
    Inventors: Hans Opower, Rolf Nowack
  • Patent number: 5930282
    Abstract: An exemplary laser apparatus comprises an amplification medium which amplifies a coherent beam passing through the amplification medium, a pump which provides energy to the amplification medium, a tunnel having a first end proximate to the pump and a second end proximate to the amplification medium, wherein the energy provided by the pump passes through the tunnel en route to the amplification medium, and a moveable member for adjusting a spatial distribution of the energy provided to the amplification medium by the pump. The moveable member typically comprises a flat, reflecting strip or flap which redirects a portion of the energy of the pump beam to a peripheral region of the amplification medium. The angular and translational position of the flap is adjustable on line so that the pump distribution can be adjusted while the laser is running to reduce observed optical distortions caused by heating of the amplification medium.
    Type: Grant
    Filed: May 19, 1997
    Date of Patent: July 27, 1999
    Assignee: General Electric Company
    Inventors: Josef Robert Unternahrer, Mark Jon Kukla, John Leo August, Jr.
  • Patent number: 5920588
    Abstract: Methods and devices for generation of phase conjugate light and wavelength conversion, and systems each having the device. In a basic structure of the present invention, a signal light beam is first separated into first and second polarization components by a polarization beam splitter. The first and second polarization components are next converted into first and second phase conjugate light beams by a single DFB (distributed feed-back) laser diode or two DFB laser diodes. In the case that a single DFB laser diode is used, the first and second phase conjugate light beams are combined by the above-mentioned polarization beam splitter. In the case that two DFB laser diodes are used, the first and second phase conjugate light beams are combined by an another polarization beam splitter. Through the structure, it can be possible to provide a phase conjugate light generator having no polarization dependence of conversion efficiency.
    Type: Grant
    Filed: April 4, 1997
    Date of Patent: July 6, 1999
    Assignee: Fujitsu Limited
    Inventor: Shigeki Watanabe
  • Patent number: 5917845
    Abstract: Superresolution elements which provide masks and are integrated into superresolution lenses, and in confocal imaging, optical disk and reprographic systems and laser pattern generation systems. The elements are phase-only elements, where the phase transmittance varies across the diameter of the element while the amplitude transmission is kept to one, although the amplitude can be varied to provide more design flexibility. These element filters can be fabricated by means of a variety of techniques including diffractive optics technology, holographic methods, thin film deposition, and as gradient-index elements.
    Type: Grant
    Filed: February 28, 1997
    Date of Patent: June 29, 1999
    Assignee: The University of Rochester
    Inventors: Tasso R. M. Sales, G. Michael Morris
  • Patent number: 5910963
    Abstract: A single-mode fiber-coupled multi-wavelength laser, wherein, for suppressing higher order transverse modes of the laser cavity than TEM.sub.oo of at least one laser emission wavelength or for increasing the beam waist diameters of the transverse laser cavity modes or for increasing the signal-to-noise level of the output of the laser at least at one emission wavelength, one or more of the following is selected:a) at least one resonator mirror movable along the resonator axis in order to vary the resonator length;b) at least one resonator mirror tiltable until a surface normal thereof encloses an angle (0.noteq.0) with the resonator axis;c) at least one resonator mirror being replaced by another concave mirror with different curvature radius;d) at least one resonator mirror being replaced by a flat mirror; ande) at least one mirror holder allowing the interchangeable use of several mirrors with different curvature radii.
    Type: Grant
    Filed: April 8, 1997
    Date of Patent: June 8, 1999
    Assignee: Carl Zeiss Jena GmbH
    Inventor: Ulrich Simon
  • Patent number: 5905751
    Abstract: A method of manufacturing a laser module is provided, which includes the steps of providing a one-piece cylindrical housing having a bore, a front window and a rear opening, securing a lens piece in the bore adjacent the front window, introducing a laser diode into the bore through the rear opening, applying a force to the laser diode to insert the laser diode into the bore while simultaneously focusing the lens, and ceasing the application of force when the lens has been accurately focused.
    Type: Grant
    Filed: September 15, 1997
    Date of Patent: May 18, 1999
    Assignee: Quarton, Inc.
    Inventors: Chao-Chi Huang, Tony K. T. Chen, Der-Shyang Jan, Ming-Chung Chiu, Yu-Hsi Yang, Teng-Yuan Chien
  • Patent number: 5889800
    Abstract: An oscillator system is provided which produces a single mode output from a multimode seed beam and a multimode optical power source. The seed source employed in the oscillator system produces a multimode seed beam that is used to injection seed a multimode optical power source. The optical power source has a short cavity such that the longitudinal modes of the multimode optical power source are sufficiently spaced apart that a mode of the optical power source can be positioned relative to the multimode seed beam such that the seed beam does not significantly overlap with neighboring longitudinal modes of the optical power source. By positioning a single longitudinal mode to overlap with the seed beam where the seed beam does not significantly overlap with neighboring longitudinal modes of the optical power source, a high energy single longitudinal mode output is produced.
    Type: Grant
    Filed: February 6, 1997
    Date of Patent: March 30, 1999
    Assignee: Spectra-Physics Lasers, Inc.
    Inventors: James Kafka, Vincent J. Newell, Michael Watts, James Clark
  • 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: 5878072
    Abstract: An alignment cross hair apparatus for partially eclipsing a laser beam includes a laser generator that emits a laser beam. A frame includes a pair of members that cross one another at an intersection within the frame. The frame is attachable to the laser generator in such a manner that the intersection of the members is within the laser beam so that the laser beam is partially eclipsed by the pair of members.
    Type: Grant
    Filed: March 25, 1997
    Date of Patent: March 2, 1999
    Assignee: SEH America, Inc.
    Inventor: Mark J. Greisz
  • 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: 5875205
    Abstract: In an optoelectronic component having a laser chip as a light transmitter and a lens coupling optics for defined emission of radiation generated in the laser chip, the lens coupling optics is arranged immediately in front of the laser chip and is adjusted and fixed in stable fashion in a simple way. The component is rationally manufactured in a wafer union. The laser chip is arranged on a common carrier between two carrier parts whose lateral surfaces neighboring the resonator faces of the laser chip are provided with mirror layers, and that are inclined at an angle of 45.degree. relative to the resonator faces. Thus the radiation generated in the laser chip is directed nearly perpendicularly upward to the surface of the common carrier and the lens coupling optics is arranged on at least the one carrier part such that the radiation generated in the laser chip impinges this lens optics nearly perpendicularly.
    Type: Grant
    Filed: February 12, 1997
    Date of Patent: February 23, 1999
    Assignee: Siemens Aktiengesellschaft
    Inventors: Werner Spaeth, Wolfgang Gramann, Hans-Ludwig Althaus, Ralf Dietrich
  • Patent number: 5859867
    Abstract: In a single-atom microlaser, a pair of opposed reflectors define a high-finesse or "high-Q" optical cavity therebetween. A source delivers a stream of multiple-energy-level atoms or particles into the cavity. Each individual atom in the stream is excited by a pump from a lower energy level to an upper energy level before injection into the cavity. The cavity resonance frequency is substantially matched to the frequency of a photon emitted by each atom as it enters the cavity. The photon is emitted due to a transition in energy between the upper level and lower level of each atom. In this manner, upon entry of a sequence of individual atoms into the cavity for example, the average number of photons resonating in the cavity exceeds one and the average number of atoms in the cavity is less than one. The photons are sustained in the high-Q cavity for a long enough time period such that the photon field interacts with the next atom in the stream.
    Type: Grant
    Filed: November 30, 1995
    Date of Patent: January 12, 1999
    Assignee: Massachusetts Institute of Technology
    Inventors: Kyungwon An, James J. Childs, Ramachandra Rao Dasari, Michael S. Feld
  • Patent number: 5852627
    Abstract: A laser having a line-narrowing output coupler. This output coupler reflects a portion of light generated in the gain medium and provides a spectral narrowing of that reflected light. A portion of the line narrowed beam is directed back into the gain medium for further amplification and a portion is transmitted as a part of the laser output. In a preferred embodiment, the laser is line narrowed in the rear as well as by the line narrowing output coupler.
    Type: Grant
    Filed: September 10, 1997
    Date of Patent: December 22, 1998
    Assignee: Cymer, Inc.
    Inventor: Alexander I. Ershov
  • Patent number: 5850407
    Abstract: A third-harmonic crystal has a Brewster-cut dispersive output surface for separating the p-polarized fundamental and third-harmonic beams without introducing losses into the beams. The output surface of the third-harmonic crystal is optically uncoated, and thus insensitive to potential ultraviolet (UV)-induced damage. Frequency doubling and tripling lithium triborate (LBO) crystals are used with a Brewster-cut Nd-YAG active medium in a resonant cavity to generate UV light at 355 nm from infrared (IR) light at 1064 nm. Except for the tripling crystal output surface, the doubling and tripling crystal optical surfaces are normal-cut and anti-reflection (AR) coated.
    Type: Grant
    Filed: November 25, 1997
    Date of Patent: December 15, 1998
    Assignee: Lightwave Electronics Corporation
    Inventors: William M. Grossman, Jason D. Henrie
  • Patent number: 5848083
    Abstract: A mounting module (submount) for a high-power heat-dissipating element comprises a mounting plate thermal-expansion-matched to the element, a high-thermal-conductivity bulk layer having stress-relief apertures, and an auxiliary plate bonded to the bulk layer opposite the mounting plate. The element is mounted on the mounting plate, while the bulk layer is attached to the mounting plate on the side opposite the element. The apertures accommodate the expansion of the bulk layer along a major dimension of the mounting plate. The apertures run transverse to the mounting plate, so as not to impede heat flow through the mounting plate. The apertures serve either as reservoirs for excess solder during module assembly, or as conduits for cooling fluid. The bulk layer comprises either stacked sheets having aperture sections defined prior to assembly, or blocks defining the apertures at the block interfaces.
    Type: Grant
    Filed: October 24, 1996
    Date of Patent: December 8, 1998
    Assignee: SDL, Inc.
    Inventors: James M. Haden, Michael P. Staskus
  • Patent number: 5838701
    Abstract: A Q-switched solid-state laser has a narrow-band laser diode (18) whose narrow-band output radiation serves as seed radiation for exciting a solid (14), with the result that only a single wavelength-stable longitudinal mode oscillates in the resonator (10, 12) of the solid-state laser and corresponding radiation (16) is emitted.
    Type: Grant
    Filed: February 20, 1997
    Date of Patent: November 17, 1998
    Assignee: Lambda Physik Gesellschaft Zur Herstellung Von Lasern mbH
    Inventors: Nils Deutsch, Thomas Schroder, Uwe Stamm, Wolfgang Zschocke
  • Patent number: 5835522
    Abstract: A laser system capable of providing light of high intensity is disclosed. This system includes a laser gain medium and three reflectors. A first reflector and a second reflector spaced from the first reflector define a laser cavity that contains the laser gain medium. Light reflected by the first reflector is amplified by the laser gain medium. A third reflector is spaced from the second reflector to define a resonant cavity external to the laser cavity. Light passes from the laser cavity to resonate in the external resonant cavity. Part of the light passes from the external resonant cavity to the laser cavity. A light-screening device, e.g., an aperture, is disposed between the second reflector and the gain medium to screen light reflected from the external cavity such that the light portion of constructive interference is preferentially passed over the light portion of destructive interference. This enables the gain medium to optically lock to the resonant frequency of the external cavity.
    Type: Grant
    Filed: November 19, 1996
    Date of Patent: November 10, 1998
    Assignee: Hewlett-Packard Co.
    Inventors: David A. King, Richard J. Pittaro, Alexander Huber
  • Patent number: 5828683
    Abstract: An optically corrected, micro-channel cooled, high density laser diode array achieves stacking pitches to 33 bars/cm by mounting laser diodes into V-shaped grooves. This design will deliver>4kW/cm2 of directional pulsed laser power. This optically corrected, micro-channel cooled, high density laser is usable in all solid state laser systems which require efficient, directional, narrow bandwidth, high optical power density pump sources.
    Type: Grant
    Filed: April 21, 1997
    Date of Patent: October 27, 1998
    Assignee: The Regents of the University of California
    Inventor: Barry L. Freitas
  • Patent number: 5825803
    Abstract: The multiple emitters laser diode assembly comprises a laser diode bar for emitting a laser beam. The laser diode bar comprises a plurality of emitters aligned with respect to each other in a same plane of emission. A graded-index elongated fiber microlens is transversely set at a given distance in front of the laser diode bar for controlling the divergence of the beam. The microlens has an axis of symmetry substantially intersecting the optical axis of each emitter. A mount is provided for positioning the microlens with respect to the laser diode bar. Alternatively, the assembly may comprise a laser diode array for emitting the beam. The laser diode array comprises a plurality of substantially parallel rows of emitters with a substantially regular period between them. An array of graded-index elongated fiber microlenses is positioned substantially parallel to the rows. Each microlens corresponds to one of the rows for collimating the beam generated thereby.
    Type: Grant
    Filed: December 14, 1995
    Date of Patent: October 20, 1998
    Assignee: Institut National d'Optique
    Inventors: Bruno Labranche, Kevin Snell, Andre Parent
  • Patent number: 5825799
    Abstract: Laser comprising a first lasing microdisk, microcylinder or microannulus defining a microcavity having a circular cross-sectional periphery and a second waveguiding micromember spaced from the first lasing micromember in a different plane and optically coupled by resonant photon tunneling. The second waveguiding micromember includes a light output coupling for providing light output from the laser without adversely affecting the Q value and low lasing threshold of the microcavity.
    Type: Grant
    Filed: May 25, 1995
    Date of Patent: October 20, 1998
    Assignee: Northwestern University
    Inventors: Seng-Tiong Ho, Daniel Yen Chu, Jian-Ping Zhang, Shengli Wu
  • Patent number: 5825801
    Abstract: The laser apparatus according to the present invention comprises an output mirror for reflecting a portion of a laser beam and transmitting therethrough a remaining thereof; a full reflection mirror located at a position opposite to this output mirror for completely reflecting a laser beam and changing the curvature; a laser medium provided between the output mirror and the full reflection mirror for causing induced emission; an aperture means for deciding a beam mode of a laser beam generated between the output mirror and the full reflection mirror and changing the aperture diameter; and a converging means for converging an outgoing laser beam from the output mirror and changing a distance from the output mirror according to a machining path; and the laser apparatus changes a curvature of the full reflection mirror and also changes a diameter of the aperture means.
    Type: Grant
    Filed: February 24, 1997
    Date of Patent: October 20, 1998
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Satoshi Nishida, Shigeto Takeshima
  • Patent number: 5812567
    Abstract: The wavelength tunable mode-locking optical fiber laser comprises non-linear amplifying loop mirror part having a light pumping lase diode, a gain medium doped optical fiber having the gain medium for oscillating the rambling light wave sequentially, a dispersion shifted optical fiber, and first polarization controller for making the continuous oscillation light wave to be maximized by adjusting the polarization of said propagating light. All elements of the non-linear amplifying loop mirror part are combined to each other in loop type on the above clock direction.
    Type: Grant
    Filed: February 4, 1997
    Date of Patent: September 22, 1998
    Assignee: Electronics and Telecommunications Research Institute
    Inventors: Min Yong Jeon, Hak Kyu Lee, Kyong Hon Kim, El Hang Lee
  • Patent number: 5812585
    Abstract: Method and arrangement for adjusting a mirror to a laser resonator such that the light impinging on said mirror is reflected on itself. A laser beam of an auxiliary gas laser circulates between the mirror to be adjusted and the output coupler mirror of the gas laser. A part of the laser beams reflected by the mirror is decoupled and projected as different light dots on a ground glass screen. By micro positioning of the mirror the different light dots are fused together to one light dot so that the light impinging on the mirror is reflected back on itself. The method and the arrangement allow a fast and exact adjustment of the mirror which further can be easily automated.
    Type: Grant
    Filed: June 21, 1996
    Date of Patent: September 22, 1998
    Assignee: Hewlett-Packard Company
    Inventors: Martin Zoll, Martin Wunderling
  • Patent number: 5802094
    Abstract: A narrow band excimer laser capable of easily adjusting the rotation of the laser beam by an image rotator provided between a laser chamber and a grating and on the laser beam optical axis. The image rotator is supported with freedom of rotation on the laser beam optical axis and rotates the laser beam about the optical axis so that the plane containing the direction in which the width of the laser beam incident upon the beam expander is narrower is parallel with the plane containing the beam-expansion direction of the beam expander, and the beam expansion direction of the laser beam incident upon the grating is perpendicular to the direction of the grooves of the grating. With this arrangement, a laser beam of narrowed bandwidth can be obtained with high efficiency.
    Type: Grant
    Filed: October 10, 1996
    Date of Patent: September 1, 1998
    Assignee: Kabushiki Kaisha Komatsu
    Inventors: Osamu Wakabayashi, Masahiko Kowaka, Yukio Kobayashi
  • Patent number: 5798877
    Abstract: An optical system is disclosed for improving the brightness symmetry of a beam emitted from a laser diode where the beam has a large width and a narrow height. The optical system includes a tilt plate for displacing one half of the width of the beam downwardly. A first beam steering prism functions to tilt the remaining, second half of the beam width in a plane parallel to the width dimension so that the second half travels towards the first half. A second beam steering prism is provided to tilt the second half of the beam so that its propagation axis is parallel to the propagation axis of the first half and wherein the second half is stacked above the first half. The optical system functions to improve the brightness symmetry of the beam by a factor of about five. The corrected beam can be used to improve the performance of a solid state laser which is end pumped by a broad area laser diode or a laser diode bar.
    Type: Grant
    Filed: December 18, 1996
    Date of Patent: August 25, 1998
    Assignee: Coherent, Inc.
    Inventors: John Lawrence Nightingale, John Anderson Trail, John Kelly Johnson
  • Patent number: 5793792
    Abstract: A laser assembly is disclosed comprising a heatsink, a laser device attached to a mounting surface of the heatsink, and a beam-shaping lens attached to an oblique surface of the heatsink, the oblique surface intersecting with the mounting surface to form an obtuse dihedral angle. The beam-shaping lens comprises a canted attachment surface which, when placed against the oblique surface, serves to optimally position the lens in relation to the laser device.
    Type: Grant
    Filed: May 21, 1997
    Date of Patent: August 11, 1998
    Assignee: Polaroid Corporation
    Inventors: Kevin A. Baxter, Douglas S. Goodman
  • Patent number: 5790576
    Abstract: Coherent light sources combining a semiconductor optical source with a light diverging region, such as a flared resonator type laser diode or flared amplifier type MOPA, with a single lens adapted to correct the astigmatism of the light beam emitted from the source is disclosed. The lens has an acircular cylindrical or toroidal first surface and an aspheric or binary diffractive second surface. The first surface has a curvature chosen to substantially equalize the lateral and transverse divergences of the astigmatic beam. Sources with an array of light diverging regions producing an array of astigmatic beams and a single astigmatism-correcting lens array aligned with the beams are also disclosed. The single beam source can be used in systems with frequency converting nonlinear optics. The array source can be stacked with other arrays to produce very high output powers with high brightness.
    Type: Grant
    Filed: June 26, 1996
    Date of Patent: August 4, 1998
    Assignee: SDL, Inc.
    Inventors: Robert G. Waarts, Robert J. Lang, Julian S. Osinski, Edmund L. Wolak, John Endriz
  • Patent number: 5768302
    Abstract: A laser system in which an intense laser beam of a predefined pumping wavelength traverses a non-linear material, such as crystalline lithium niobate, that has been impressed with one or more quasi phase matching (QPM) gratings is disclosed. Quasi phase matching compensates for the dispersion or birefringence in a non-linear material by modulating the non-linearity with the proper period such that the different wavelengths involved in the non-linear process stay in phase over a long interaction length. The first QPM grating promotes the parametric generation of a resonant signal whose wavelength is determined by the grating period. According to the invention, either a second QPM grating impressed in the same medium or a different order of the first QPM grating promotes the non-linear interaction between the resonant signal and another optical signal traversing the non-linear material.
    Type: Grant
    Filed: May 20, 1997
    Date of Patent: June 16, 1998
    Assignee: Lightwave Electronics Corporation
    Inventors: Richard W. Wallace, Walter R. Bosenberg, Jason I. Alexander
  • Patent number: 5757830
    Abstract: In an apparatus and method for aligning a microlens relative to an edge-emitting semiconductor laser, the components are aligned and coupled without the need for intermediate optics. An edge-emitting semiconductor laser is mounted to a support body which preferably operates as a heat sink. The support body has a side face, which is substantially parallel by the emitting face of the laser. The microlens is formed on a lens substrate. The lens substrate is mounted adjacent the emitting face of the laser and further mounted adjacent the side face of the support body such that the optical axis of the lens substantially aligns with the optical axis of the laser. A substantial portion of the lens substrate extends along the plane of the side face of the support body. The invention has applications in coupling high-power laser energy into fiber optics and in optical computing devices requiring arrays of lasers.
    Type: Grant
    Filed: February 7, 1996
    Date of Patent: May 26, 1998
    Assignee: Massachusetts Institute of Technology
    Inventors: Zong-Long Liau, Dean Z. Tsang, James N. Walpole
  • Patent number: 5754582
    Abstract: The present invention relates to laser leveling device suitable for construction. The present invention uses a standard low cost laser diode module as the laser source and optical system. A novel method is provided to align the non-collimated beam emitted from the standard low cost laser diode module so that it is perpendicular to the rotational axis of the laser level. The present invention describes a laser level which can be operated in four different modes: dot mode, line mode, oscillation mode and plane mode. Dot mode provides two level laser dots. Line mode provides a short bright level line. Oscillation mode provides a long bright reference line. Plane mode provides a level 360 degree reference plane. The invention also provides a structure which allows two vertical reference planes which are perpendicular to each other and perpendicular to the horizontal reference plane to be generated.
    Type: Grant
    Filed: February 25, 1997
    Date of Patent: May 19, 1998
    Assignee: Momentum Laser, Inc.
    Inventor: Dawei Dong
  • Patent number: 5751750
    Abstract: A laser system with compensated optics contains at least one optical element which is thermally coupled to a heat source in order to thermally compensate for a deformation of optical elements disposed in a beam path of the laser system. The deformation is brought about by the laser beam.
    Type: Grant
    Filed: February 10, 1997
    Date of Patent: May 12, 1998
    Assignee: Rofin-Sinar Laser GmbH
    Inventors: Dirk Friede, Hermann Hage, Karl-Heinz Herzner, Volker Scholz
  • Patent number: 5751751
    Abstract: A monolithic diode pumped solid-state laser (11) comprising as the laser host neodymium-doped yttrium orthovanadate (Nd:YVO.sub.4) (12, 52) or neodymium-doped gadolinium orthovanadate (Nd:GdVO.sub.4) (57, 67) operating on the .sup.4 F.sub.3/2 .fwdarw..sup.4 I.sub.9/2 (.about.914 nm or .about.912 nm respectively) transition, to which a suitable nonlinear optic material (16), such as potassium niobate (KNbO.sub.3) or beta barium borate (BBO), is bonded. The nonlinear crystal gives rise to intracavity frequency doubling to .about.457 or .about.456 nm. The microlaser is a composite cavity formed from a gain medium crystal and a nonlinear frequency doubling material which together have four spaced parallel dielectrically coated faces (14, 17, 18, 15) and which is positioned in close proximity to a diode laser pump source (13) for phase-matched harmonic generation of blue light along an axis of propagation which lies substantially perpendicular to the two faces of the composite cavity.
    Type: Grant
    Filed: October 21, 1996
    Date of Patent: May 12, 1998
    Assignee: Laser Power Corporation
    Inventors: David E. Hargis, Sven E. Nelte
  • Patent number: 5745511
    Abstract: Method for making a custom phase-conjugating diffractive mirror for a laser resonator comprising the steps of: (a) choosing a specified beam mode profile a.sub.1 (x,y) that will suit need of said designer, (b) calculating the mode profile b(x',y') which is a value of the specified beam a.sub.1 (x,y) that is propagated to the reflection surface of the diffractive mirror and (c) calculating mirror reflectance t(x',y') which reflects phase conjugate of b(x',y'). A method for fabricating such a mirror is shown. Another aspect of the invention is the addition of a phase adjusting element into a laser resonator, and compensating for the addition of a phase adjusting element in the design of other phase-adjusting elements such as the mirrors.
    Type: Grant
    Filed: July 16, 1996
    Date of Patent: April 28, 1998
    Assignee: Regents of the University of Minnesota
    Inventor: James R. Leger
  • Patent number: 5742633
    Abstract: An asymmetric resonant optical cavity is constructed of an optically transmissive dielectric material having an index of refraction n. The cavity is configured as an oval cross-section of area A, having major and minor axes. An optical input couples an optical signal of wavelength .lambda. into the cavity. An output coupler is positioned in a near-field region of a surface point of the cavity, thereby enabling coupling thereinto of optical energy of wavelength .lambda.. The surface point on the cavity is determined by a minimum value of an expression which relates the Sin of the angle of incidence, at an angle .phi., to the curvature of the outer surface of the cavity. Further, the index of refraction n of the cavity's dielectric is chosen so as to avoid emission of physically separated beams at the point of exit of a beam.
    Type: Grant
    Filed: October 2, 1996
    Date of Patent: April 21, 1998
    Assignee: Yale University
    Inventors: Alfred Douglas Stone, Richard Kounai Chang, Jens Uwe Noeckel
  • Patent number: 5732100
    Abstract: The invention relates to a microlaser cavity having an active laser medium and reflection means at the entrance and exit of the cavity, characterized in that the reflection means are dimensioned in such a way that, in the active medium, the size of a pumping beam is at the most equal to the size of a laser beam emitted by the cavity.
    Type: Grant
    Filed: January 17, 1996
    Date of Patent: March 24, 1998
    Assignee: Commissariat a l'Energie Atomique
    Inventors: Philippe Thony, Engin Molva
  • Patent number: 5729568
    Abstract: In order to improve a semiconductor laser system with a plurality of semiconductor laser units comprising a laser oscillator, laser radiation exiting from each of these units, a light-conducting fiber associated with each semiconductor laser unit, a coupling element for coupling the laser radiation exiting from the respective semiconductor laser unit into the respective light-conducting fiber, and a fiber bundle comprising the fibers as light conductor system, a total laser radiation formed by the sum of the coherent laser radiation generated by the respective semiconductor laser units exiting from one end of the fiber bundle, this total laser radiation illuminating a target surface on an object to be irradiated during laser activity of all the semiconductor laser units, such that complex irradiation tasks can be performed with this system in a simple and as effective a manner as possible it is suggested that a control be provided for controlling the power of each individual semiconductor laser unit in a defi
    Type: Grant
    Filed: May 30, 1996
    Date of Patent: March 17, 1998
    Assignees: Deutsche Forschungsanstalt fuer Luft-und Raumfahrt e.V., Universitaet Stuttgart Institut fur Strahlwerkzeuge
    Inventors: Hans Opower, Helmut Huegel, Adolf Giesen, Friedrich Dausinger
  • Patent number: 5727014
    Abstract: A vertical-cavity surface-emitting laser that generates light having a fixed direction of polarization. The laser has a plane light-generating region sandwiched between a first conductive mirror region and a second conductive mirror region. The first conductive mirror region has an opposite conductivity mode from the second conductive mirror region. The first conductive mirror region has a remote surface substantially parallel to the light-generating region and an electrode formed on the remote surface. The electrode bounds a light emission port from which the light is emitted in a direction defining an axis. A reduced-conductivity region is formed in the first conductive mirror region surrounding the axis and extending from the remote surface towards the light-emitting region to define a core region in the first conductive mirror region. The light emission port and/or the core region has first and second dimensions in orthogonal directions in a plane parallel to the light-generating region.
    Type: Grant
    Filed: October 31, 1995
    Date of Patent: March 10, 1998
    Assignee: Hewlett-Packard Company
    Inventors: Shih-Yuan Wang, Michael R. T. Tan, William D. Holland, John P. Ertel, Scott W. Corzine
  • Patent number: 5723881
    Abstract: A dual-beam laser diode is provided and includes a base, a first laser diode mounted on the base and having a laser emitting body controlled to emit a laser beam, and a second laser diode mounted between the base and the first laser diode and having a laser emitting body. The second laser diode has a laser emitting body spaced from the laser emitting body of the first laser diode within the range of 3 .mu.m to 5 .mu.m, and controlled to emit a laser beam partially overlapped on the laser beam of the first laser diode. The laser beams of the first laser diode and second laser diode can have different wavelengths and light spot patterns.
    Type: Grant
    Filed: December 4, 1996
    Date of Patent: March 3, 1998
    Assignee: Quarton Inc.
    Inventor: Kuo-Ti Chen