Specified Cavity Component Patents (Class 372/98)
  • Patent number: 5105433
    Abstract: A semiconductor laser which includes a controllable beam splitter has three segments including laser-active zones and a monitor diode forming a cross-shaped laser connected with one another by way of the beam splitter. The beam splitter is equipped with electrodes for controlling optical coupling between the segments.
    Type: Grant
    Filed: September 14, 1990
    Date of Patent: April 14, 1992
    Assignee: Alcatel N.V.
    Inventors: Hartmut Eisele, Olaf Hildebrand, Albrecht Mozer, Michael Schilling, Heinz Schweizer, Klaus Wunstel, Ulrich Spalthoff
  • Patent number: 5093837
    Abstract: A scatter shield attenuates off-axis illumination emanating from a light beam projector. The scatter shield comprises an elongate housing, usually cylindrical, having at least two baffles therein. The dimensions of the scatter shield are selected to assure that off-axis illumination exceeding a preselected angle of divergence is internally reflected within the shield at least three times. Such multiple reflections provide for highly efficient attenuation.
    Type: Grant
    Filed: March 8, 1991
    Date of Patent: March 3, 1992
    Assignee: S-Tron
    Inventor: Oliver J. Edwards
  • Patent number: 5084884
    Abstract: According to the invention, a probe laser beam having a wavelength which is different from that of the laser beam emitted from a laser apparatus is introduced into the apparatus to adjust the optical device so that any fluctuations in the probe laser beam passing through or reflected from the optical device may be eliminated. Therefore, any fluctuations in output power and/or the oscillation wavelength of the narrowed bandwidth laser beam emitted from the apparatus can be directly detected and the laser apparatus can be so controlled as to ensure a stabilized operation under an optimum condition.
    Type: Grant
    Filed: August 1, 1990
    Date of Patent: January 28, 1992
    Assignee: Mitsui Petrochemical Industries, Ltd.
    Inventor: Mitsugu Terada
  • Patent number: 5081635
    Abstract: An apparatus for controlling an output from an excimer laser device wherein at least two etalons each having a large diameter are arranged between a rear mirror and a laser chamber for the excimer laser device is disclosed. With the apparatus, the operative range of laser light outputted from the excimer laser device can be narrowed by executing superposition control for a wavelength of laser light which transmits through each etalon, while maintaining the number of spatial lateral modes. The apparatus is preferably employable as a light source particularly for a unit for projecting and exposing figures in a reduced size. Superposition control with the use of a superposition control unit, excitation intensity control for laser gas with the use of an excitation intensity control unit and partial gas replacement control for laser gas with the use of a gas control unit are executed in a predetermined timing relationship, respectively.
    Type: Grant
    Filed: February 26, 1990
    Date of Patent: January 14, 1992
    Assignee: Kabushiki Kaisha Komatsu Seisakusho
    Inventors: Osamu Wakabayashi, Noritoshi Ito, Masahiko Kowaka
  • Patent number: 5068861
    Abstract: An apparatus for applying a load to an etalon so as to enable the accurate tuning of desired frequencies or ranges of frequencies. The invention includes first and second optical surfaces separated and disposed highly parallel with respect to each other by an electric longitudinal spacer member. A biasing means applies a longitudinal load to the elastic longitudinal spacer member. The applied load is uniformly distributed throughout the spacer member by a longitudinal load distribution means, which is disposed between said biasing means and at least one of said optical surfaces. The distance, d, between the first and second optical surface is directly proportional to the load applied by the biasing means. The load may be varied, in one embodiment of the invention, using a bias adjustment means acting in mechanical cooperation with the biasing means.
    Type: Grant
    Filed: July 19, 1990
    Date of Patent: November 26, 1991
    Assignee: Spectra-Physics Lasers, Inc.
    Inventors: Rexford J. Abbott, David L. Wright
  • Patent number: 5061065
    Abstract: In a particle detecting instrument, a particle detecting cell comprises a laser plasma tube in combination with a glass prism through which a fluid channel is defined. The glass prism abuts the transmitting end of the laser plasma tube and the end wall of the prism is arranged at the brewster angle with respect to the plasma tube axis. The fluid channel defined in the prism is also arranged at the brewster angle with respect to the laser beam passing through the prism. A mirror is provided on the prism to reflect the light back through the prism into the plasma tube. The mirror is positioned so that the light reflected back into the plasma tube is in phase with the light amplified within the plasma tube. A mount is provided for the mirror to adjust its lateral and angular position. In an alternative embodiment, the plasma tube abuts a glass window pane defining one side wall of a fluid channel to receive a gas entraining particles to be measured.
    Type: Grant
    Filed: October 20, 1989
    Date of Patent: October 29, 1991
    Assignee: Pacific Scientific Company
    Inventor: Holger T. Sommer
  • Patent number: 5046184
    Abstract: A passively mode-locked laser suitable for use with homogeneously broadened lasing medium or a lasing medium having a high-power output, long relaxation time or a narrow bandwidth. The laser includes a main cavity in which the lasing medium is disposed and an external cavity including a non-linear element. The non-linear element is selected to induce a non-linear phase shift in a coherent beam from the main cavity. In operation, a portion of a laser beam in the main cavity is coupled to the external cavity and a phase-shifted output from the external cavity is reflected back into the main cavity to provide a narrow pulse, mode-locked output from the laser. In one embodiment the non-linear element of the external cavity is an optical fiber with a mirror disposed adjacent one end of the optical fiber to provide dual propagation of a laser pulse through the fiber. In high-power applications the external cavity mirror is disposed proximate but spaced apart from the optical fiber end.
    Type: Grant
    Filed: April 5, 1990
    Date of Patent: September 3, 1991
    Assignee: University of California
    Inventors: Joseph K. Chee, Eric C. T. Cheung, Mo-Nga Kong, Jia-Ming Liu
  • Patent number: 5034950
    Abstract: A laser application system comprises an amplifier and two rotating polarization devices so that a laser beam is given with linear polarization which is converted into a circular polarization. Then the beam passing through amplifier means, is reflected into a second pass and reflected back to the amplifier. The system further includes a stimulated Brillouin scattering non-linear isolator for transmitting substantially all of the light beam when its energy is below a predetermined threshold and reflecting substantially all of the light beam without substantially reducing the quality of the beam, when its energy exceeds the threshold.
    Type: Grant
    Filed: May 9, 1990
    Date of Patent: July 23, 1991
    Assignee: The State of Israel, Atomic Energy Commission, Soreq Nuclear Research Center
    Inventors: Steven M. Jackel, Raphael Lallouz
  • Patent number: 5033061
    Abstract: A servo alignment method and apparatus for maintaining laser beam alignment. An operating parameter of the laser (such as output beam power) is measured, and error signals are generated from the measured operating parameter signal for controlling the laser beam alignment. In one class of embodiments, modulation signals are supplied to an intra-cavity component of a laser system to modulate the beam path. The beam path may be modulated by reciprocating a laser resonator mirror about a mirror axis or two substantially orthogonal mirror axes. In the latter case, the mirror may be vibrated about the axes either alternately (first about one axis and then about the other) or simultaneously.
    Type: Grant
    Filed: June 11, 1990
    Date of Patent: July 16, 1991
    Assignee: Coherent, Inc.
    Inventors: James L. Hobart, Wayne S. Mefferd, Bruce Peuse
  • Patent number: 5023885
    Abstract: An external optical resonator for a semiconductor laser is composed of an optical directional coupler which can be formed as an integrated optical coupler with a short structural length that enables a free spectral range in the order of 100 GHz and enables the resonator and the system fiber to be coupled to the same end face of the laser. The resonator structure includes two optical waveguides with feedback means applied on the end faces of one of the waveguides and the other waveguide having one end face coupled to receive the output of the laser and the other end face of the other waveguide being coupled to the system fiber. The arrangement is particularly useful for tunable semiconductor lasers, particularly for heterodyne reception.
    Type: Grant
    Filed: July 24, 1989
    Date of Patent: June 11, 1991
    Assignee: Siemens Aktiengesellschaft
    Inventors: Franz Auracher, Eckhard Meissner, Bernd Noll, Julius Wittmann
  • Patent number: 4993041
    Abstract: An optically pumped laser comprising a securing arrangement (14) for the bar assuring, on one hand, the rigid interconnection of the bar (4) and the framework (12a, 12b, 12c, 12d) by gripping the former and in bearing on the latter and, on the other hand the thermal insulation of the lateral faces of the bar. The securing arrangement (14) is obtained from an elastically deformable fitting of plastics material.
    Type: Grant
    Filed: February 8, 1990
    Date of Patent: February 12, 1991
    Assignee: Asulab S.A.
    Inventors: Thomas Sidler, Jean-Charles Poli
  • Patent number: 4979180
    Abstract: A modular interchangeable laser instrumentation system for applications in industrial processing, medical surgery and treatment, dental treatment, metrology, military applications, forensic investigation, micromachining, optical storage, spectroscopy, research and many other related applications. The system principally comprises a handheld stylus with interchangeable modules to produce various selected laser-radiation beams for any particular work as needed. Each module and the combined modular stylus is adapted to produce a particular type of laser beam for the intended project in hand, and as the modular section of one stylus is replaced by the modular section of another stylus, the generated laser beam assumes a different optical and spectral character, so as to be compatible with the work under process and characterized by the type of material and thickness thereof, texture, or human anatomical tissue of one kind or another, requiring different focus intensities and modal formats.
    Type: Grant
    Filed: November 24, 1989
    Date of Patent: December 18, 1990
    Inventor: Arthur M. Muncheryan
  • Patent number: 4979181
    Abstract: In a vacuum laser irradiating apparatus disposed between a laser generator and a vacuum vessel in which an object to be irradiated with a laser beam is placed, an outer window plate is airtightly fixed to the outer opening of the apparatus body to maintain the internal cavity of the apparatus body under a vacuum and to pass the laser beam therethrough. This outer window plate is reinforced so as not to be distorted due to pressure difference between an inside vacuum of the apparatus body and an outside atmospheric pressure. This is because the outer window plate is made of an expensive pure monocrystalline material and therefore it is preferably to reduce the thickness thereof for material cost reduction.
    Type: Grant
    Filed: April 3, 1990
    Date of Patent: December 18, 1990
    Assignee: Nissan Motor Co., Ltd.
    Inventors: Megumi Nakanose, Naoyuki Koyama, Mitsunori Aoshiba, Tadao Motegi
  • Patent number: 4977562
    Abstract: A method and apparatus for stabilizing the frequency at which a laser cavity oscillates comprising a passive system which provides a plurality or continuum of optical paths of differing lengths. The various paths correspond to differences in mode parameters in the cavity, and involve compensating changes in polarization, beam direction, beam divergence, and the like, in exchange for a constant optical path length in the laser cavity. The unchanging optical path length results in a stable frequency of oscillation despite physical changes in the cavity which might otherwise alter that path length.
    Type: Grant
    Filed: October 19, 1989
    Date of Patent: December 11, 1990
    Assignee: LTV Aerospace and Defense Co.
    Inventors: Albert B. Welch, Marion W. Scott
  • Patent number: 4975925
    Abstract: Ceramic bearings and races, each coated or implanted with metal, glass, boron fibers, carbon fibers, jade or horneblende are disclosed as bearings for the fan assembly of a laser. The bearings and races may be silicon nitride implanted with gold and may be used in the laser without potentially contaminating supplemental lubricants.
    Type: Grant
    Filed: November 1, 1989
    Date of Patent: December 4, 1990
    Assignee: The Spectranetics Corporation
    Inventor: G. Stephan Derrickson
  • Patent number: 4965803
    Abstract: A room-temperature, laser-pumped, Q-switched, thulium-doped, solid state laser for producing pulses of laser emission at substantially 2 microns is disclosed. In a preferred embodiment, the laser comprises: a laser cavity defined by first and second reflective elements opposing each other on a common axis to form a reflective path therebetween; a laser crystal disposed in the laser cavity, the laser crystal having a host material doped with an amount of thulium activator ions sufficient to produce a laser emission at substantially 2 microns from the .sup.3 F.sub.4 to .sup.3 H.sub.
    Type: Grant
    Filed: March 30, 1990
    Date of Patent: October 23, 1990
    Assignee: The United Stats of America as represented by the Scretary of the Navy
    Inventors: Leon Esterowitz, Robert C. Stoneman
  • Patent number: 4951288
    Abstract: Sensitive components of a laser such as a resonator mirror, a decoupling mirror or the like, are protected against an initial laser beam surge caused by the ignition of a laser with an arc discharge lamp, by a beam interrupting switch having two switch sections each carrying a filter or shutter switchable into a laser beam path in response to an arc discharge lamp ignition pulse. For a beam interruption the filters or shutters are located directly in front of and directly behind of a lasing element as viewed in the beam path direction. The switch sections are operated by a shifting mechanism responsive to the ignition pulse to bring the switch sections into the beam path and to a control signal to bring the switch sections out of the beam path or into a beam releasing position.
    Type: Grant
    Filed: August 28, 1989
    Date of Patent: August 21, 1990
    Assignee: Messerschmitt-Boelkow-Blohm GmbH
    Inventors: Udo Barton, Gerhard Ruf, Fritz Wondrazek
  • Patent number: 4946629
    Abstract: (i) A compound of the formula: ##STR1## wherein R is H, a metal or a group containing a tetravalent N atom;X is ##STR2## R.sup.1 is NO.sub.2, CN or COOY; Y is H, C.sub.1-4 -alkyl, a metal or a group containing a tetravalent N atom;R.sup.2 & R.sup.3 are each independently H or a non-hydrophilic aliphatic or cycloaliphatic group containing up to 30 carbon atoms;R.sup.4 & R.sup.5 are each independently H or a non-hydrophilic aliphatic or cycloaliphatic group containing up to 30 carbon atoms;and R.sup.6 & R.sup.7 are each independently H or a non-hydrophilic group containing up to 4 carbon atoms;or R.sup.4 & R.sup.6 together comprise ring fused to Ring A and R.sup.5 & R.sup.7 are as hereinbefore defined;or R.sup.5 & R.sup.7 together comprise ring fused to Ring A and R.sup.4 & R.sup.6 are as hereinbefore defined;or R.sup.2 & R.sup.4 together with the N atom to which R.sup.2 is attached from a ring fused to Ring A and R.sup.3 & R.sup.5 are as hereinbefore defined;or R.sup.3 & R.sup.
    Type: Grant
    Filed: November 25, 1988
    Date of Patent: August 7, 1990
    Assignee: Imperial Chemical Industries, Plc
    Inventors: Simon Allen, Paul F. Gordon, Richard A. Hann
  • Patent number: 4939739
    Abstract: A servo alignment method and apparatus for maintaining laser beam alignment. An operating parameter of the laser (such as output beam power) is measured, and error signals are generated from the measured operating parameter signal for controlling the laser beam alignment. In one class of embodiments, modulation signals are supplied to an intra-cavity component of a laser system to modulated the beam path. The beam path may be modulated by reciprocating a laser resonator mirror about a mirror axis or two substantially orthogonal mirror axes. In the latter case, the mirror may be vibrated about the axes either alternately (first about one axis and then about the other) or simultaneously.
    Type: Grant
    Filed: April 24, 1989
    Date of Patent: July 3, 1990
    Assignee: Coherent, Inc.
    Inventors: James L. Hobart, Wayne S. Mefferd, Bruce Peuse
  • Patent number: 4935939
    Abstract: A surface emitting laser is described with a monolithic integrated lens formed in one side of an optical semiconductor substrate aligned with a parabolic light reflective mirror surface formed adjacent an edge emitting laser formed on, or in, the other side of the substrate. An optional optical feedback spherical mirror is formed concentric to the lens.
    Type: Grant
    Filed: May 24, 1989
    Date of Patent: June 19, 1990
    Inventors: Zong-Long Liau, James N. Walpole
  • Patent number: 4933945
    Abstract: The invention is directed to a laser arrangement for converting frequency wherein the fundamental frequency or the converted frequency can be selectively emitted by means of an optical element which can be pivoted into and out of the beam path. An especially slim configuration of the overall arrangement is obtained with the aid of an additional deflection element.
    Type: Grant
    Filed: September 18, 1989
    Date of Patent: June 12, 1990
    Assignee: Carl-Zeiss-Stiftung
    Inventors: Martin Blumentritt, Peter Greve, Wolfgang Rupp
  • Patent number: 4912720
    Abstract: Polytetrafluoroethylene (PTFE), or like polymeric material is provided for use as a laser cavity material to efficiently couple flash lamp emissions into the laser medium due to its exceptionally high diffuse reflectance characteristic of better than 99%, which increases the laser output by as much as 100%. In one embodiment, a unique technique for fabricating the cavity includes both sintering and providing an optimal packing density prior to sintering, with the sintering to take place at atmospheric pressure to preserve the optimal packing density as closely as possible in the sintered product. This provides an optimal void percentage for optimal reflectivity. For PTFE, packing densities approaching 1.0 g/cm.sup.3 yield an opaque optimally reflective material.
    Type: Grant
    Filed: October 27, 1988
    Date of Patent: March 27, 1990
    Assignee: Labsphere, Inc.
    Inventor: Arthur W. Springsteen
  • Patent number: 4910739
    Abstract: An adjustable aperture is formed by a plurality of spring members secured over a passage on a frame, each spring member having a first end secured to the frame, a body extending into the passage and a second end opposite the first. The flexible members are mounted so that the plurality of second ends of the spring members form the aperture. A plunger, secured to the frame and contacting the bodies of the spring members, is provided for deflecting the spring members in an adjustable mount along the axis of light going through the passage. By deflecting the spring members which are fixed to the frame, the size of the aperture formed by the second ends of the spring members can be adjusted. The aperture formed is well suited for control of transverse modes in lasers.
    Type: Grant
    Filed: March 21, 1988
    Date of Patent: March 20, 1990
    Assignee: Spectra-Physics
    Inventor: Shinan-Chur S. Sheng
  • Patent number: 4905252
    Abstract: Diffraction limited, single narrow lobe radiation from a large area laser is achieved in a system using an external ring laser cavity to return radiation to the laser via a spatial filter and a Faraday rotator. An antireflectance coating of sufficiently small reflectivity added to the large area laser converts it into a laser amplifier which provides optical gain in a ring laser cavity.
    Type: Grant
    Filed: September 16, 1988
    Date of Patent: February 27, 1990
    Assignee: United States of America as represented by the Secretary of the Navy
    Inventors: Lew Goldberg, Joseph F. Weller
  • Patent number: 4891818
    Abstract: A rare gas-halogen excimer laser in which the laser gases are exposed only to compatible materials that react with the laser gases to produce stable reaction products having a low vapor pressure, so as to reduce contamination of the gases and optics. High-purity nickel is the preferred material for components that are electrically conductive, and high-purity alumina is the preferred material for components that are non-electrically conductive. No non-compatible materials are used. In another feature, magnetic fluid seals are provided for the laser's fan-shaft, to isolate the shaft bearings and thereby isolate any non-compatible lubricant for the bearings. The fan uses magnetic coupling so that an isolating enclosure may be placed over the magnetic fluid seal to prevent the leakage of gases into the surrounding environment if the seal ever fails.
    Type: Grant
    Filed: March 13, 1989
    Date of Patent: January 2, 1990
    Assignee: Acculase, Inc.
    Inventor: Jeffrey I. Levatter
  • Patent number: 4887276
    Abstract: An improved shared aperture sampler for high power laser beams includes a buried mirror positioned behind a dichroic reflective surface that reflects the high power beam and permits the sample beam to pass through and to be focused or deflected by the buried mirror.
    Type: Grant
    Filed: April 16, 1987
    Date of Patent: December 12, 1989
    Assignee: United Technologies
    Inventor: John H. Bluege
  • Patent number: 4884281
    Abstract: A compact, laser diode pumped, high efficiency, solid-state laser comprises an output coupler mirror forming a front end of a laser cavity. A back end of the laser cavity is formed by a rear mirror through which emissions from a laser diode pass for pumping a laser chip of stoichiometric lasing material. A frequency doubler chip is positioned immediately adjacent the laser chip to double the frequency of light generated by the laser chip and thereby halve its wavelength. The laser chip is bonded to the frequency doubler chip by coupling material having a refractive index matched to the chips to nearly eliminate reflections at the bonded chip surfaces. Such bonding increases the effective Q of the laser cavity which receives the bonded combination of the laser chip and the doubler chip at a beam waist defined within the laser cavity by means of beam shaping with the laser chip being positioned to receive pumping energy from a laser diode through the rear mirror of the laser cavity.
    Type: Grant
    Filed: September 9, 1988
    Date of Patent: November 28, 1989
    Assignee: Spectra-Physics, Inc.
    Inventors: Pliny S. Hawthorn, Mark D. Sobottke
  • Patent number: 4872181
    Abstract: A laser resonator generates a polarized output beam with a laser medium exhibiting thermally induced birefringence and a Y-shaped resonant cavity. A lasing axis extends between a first side and a second side of the laser medium, Radiation transmitted out of the first side of the laser medium has its polarization rotated by 90 degrees and is guided back along the lasing axis into the laser medium for a second pass. A polarizer is mounted on the second side of the laser medium for guiding the radiation having a first polarization along a first path and radiation having a second polarization that is 90 degrees from the first polarization along a second path. Both the first path and the second path include the lasing axis of the laser medium and form a Y-shaped resonant cavity. Along the first path, a high reflecting means is provided to reflect the radiation back along the first path.
    Type: Grant
    Filed: November 21, 1988
    Date of Patent: October 3, 1989
    Assignee: Spectra-Physics
    Inventors: Bertram C. Johnson, Richard L. Herbst
  • Patent number: 4868834
    Abstract: A rapidly tunable low pressure laser comprised of a one electrode pair low ressure CO.sub.2 gas laser gain cell and intra-cavity quarterwave plate and Q-switch. The cell has a fixed laser output coupled at one end of the laser cavity and at the other end of the cavity a wavelength switching device which changes laser lines in less than 1.times.10.sup.-3 .mu.sec, i.e. changes the wavelengths in less than 1 millisecond within the low pressure laser, to produce at least two quick pulses of different wavelengths at a separation of 1 millisecond. The wavelength switching device is comprised of a fast rotating mirror on the laser optical axis and a fixed grating, or a rotating grating on the optical axis.
    Type: Grant
    Filed: September 14, 1988
    Date of Patent: September 19, 1989
    Assignee: The United States of America as represented by the Secretary of the Army
    Inventors: Jay A. Fox, Jeffrey L. Ahl
  • Patent number: 4866726
    Abstract: A bore support assembly is used in construction of an outer envelope of a laser and for supporting an inner bore tube of the laser near its free end. The bore support assembly includes a generally planar joiner ring having radially spaced outer and inner peripheries. At its outer periphery, it becomes rigidly attached to the interior of the envelope during formation of the latter from separate bore assembly tube and reservoir tube sections. Its inner periphery has a central opening receiving the bore tube. The bore support assembly also includes a spider structure and a preform element for attaching it to the exterior of bore tube. The spider structure has an outer peripheral portion attached to the inner periphery of the joiner ring so as to position the spider structure on one side of the joiner ring and along the central opening thereof.
    Type: Grant
    Filed: June 15, 1988
    Date of Patent: September 12, 1989
    Assignee: Spectra Physics, Inc.
    Inventors: Mark V. Ortiz, William A. Shull
  • Patent number: 4860305
    Abstract: An external cavity type semiconductor laser apparatus comprising a semiconductor laser device and an external cavity, which are mounted on a single mounting base with a space therebetween, wherein laser light emitted from the light-emitting rear facet of the laser device is reflected by the external cavity and returns to the laser device. The reflectivity of the light-emitting rear facet of the laser device being different from that of the light-emitting front facet of the laser device.
    Type: Grant
    Filed: February 26, 1988
    Date of Patent: August 22, 1989
    Assignee: Sharp Kabushiki Kaisha
    Inventors: Nobuyuki Miyauchi, Hidenori Kawanishi, Shigeki Maei, Osamu Yamamoto, Hiroshi Hayashi
  • Patent number: 4858240
    Abstract: An arrangement for the generation of CO.sub.2 laser pulses of high power. In a first step, the laser medium is brought by an electrical pumping pulse into a state of extremely high population inversion and, in a second step, this inversion is decayed suddenly by a Q-switching effect in such a manner, that radiation pulses of extreme power magnification arise. The power is supplied to the laser-gas discharge by a power-supply unit which permits the pulsed supply of pumping energy. The associated laser resonator is formed froma first resonator mirror with a fixed reflectivity R.sub.1,frequency-selective element,a special, highly angle-selective gas discharge tube,and a special component material transparent to the laser radiation that functions as a second resonator mirror with a variable reflectivity R.sub.2. The second unit is comprised of a modulator with a high cutoff frequency in the form of a Fabry-Perot interferometer arrangement with a rapidly changeable optical wavelength.
    Type: Grant
    Filed: November 26, 1986
    Date of Patent: August 15, 1989
    Assignee: VEB Kombinat Feinmechanische Werke Halle
    Inventors: Manfred Pohler, Gisbert Staupendahl, Richard Wittig
  • Patent number: 4856018
    Abstract: A reduced projection light source comprises a laser device for emitting laser light having a transverse mode of multimodes, and an etalon located between a chamber of the laser device and a total reflection mirror. The light source is used as an exposure light source for transfer printing an ultrafine pattern on a semiconductor wafer.
    Type: Grant
    Filed: January 20, 1987
    Date of Patent: August 8, 1989
    Assignee: Kabushiki Kaisha Komatsu Seisakusho
    Inventors: Yasuhiro Nozue, Koichi Kajiyama, Kaoru Saito, Osamu Wakabayashi, Masahiko Kowaka, Yasuo Itakura
  • Patent number: 4847854
    Abstract: An optical resonator for a laser includes an optical element mounted for rotation about two mutually transverse axes and controllable by a computer for automatically adjusting the orientation of the optical element.
    Type: Grant
    Filed: November 13, 1987
    Date of Patent: July 11, 1989
    Inventor: Johannes W. Van Dijk
  • Patent number: 4845716
    Abstract: An arrangement for the wavelength-selective internal intensity modulation and radiation pulse generation of high power CO.sub.2 lasers, in a high-power CO.sub.2 laser is forced to operate in the resonator at a freely selectable but fixed wavelength by means of a frequency-selective element and highly angle-selective gas discharge tubes. The possibility of rapidly Q-switching is provided by a special interferometer arrangement of variable reflectivity, functioning as an uncoupling element. The arrangement may furthermore be used for the rapid stabilization of the laser power.
    Type: Grant
    Filed: November 26, 1986
    Date of Patent: July 4, 1989
    Assignee: VEB Kombinat Feinmechanische Werke Halle
    Inventors: Manfred Poehler, Gisbert Staupendahl, Richard Wittig
  • Patent number: 4835785
    Abstract: An optical assembly isolator and laser system incorporating the same. The isolator attaches to an end of the laser system along the optical axis of the laser system. The isolator includes a flow loop wall, an optical assembly wall, an outer wall connecting the foregoing two walls, and at least one baffle wall included in the volume defined by the outer wall. The flow loop wall and the baffle wall include open first and second apertures, and the optical assembly wall supports an optical assembly. When the isolator is in place on the laser system, the first and second apertures and the optical assembly all align with the optical axis of the laser system. The edges of the first aperture and the flow loop wall can be slanted and oriented with respect to the primary flow through the laser system to induce a small circulation and redirect any entering shock waves and entrained contaminated gas toward the outer wall.
    Type: Grant
    Filed: September 30, 1987
    Date of Patent: May 30, 1989
    Assignee: Spectra-Physics, Inc.
    Inventor: William J. Thayer
  • Patent number: 4823357
    Abstract: A laser transmitter is disclosed in which the laser combines the outputs of numerous laser diodes using dichroic combination to produce a high power, diffraction limited beam which may be transmitted at minimum beam divergence using the full aperture of the transmitter telescope. The individual diode beams are combined and superimposed in the laser, and are transmitted superimposed in the near and far field of the transmitter telescope. The dichroic combining process is as follows. A collimate beam of a first wavelength is directed at a narrowband or long wave pass filter which is tilted slightly (about 10 degrees). This beam passes through the filter. A beam of a second wavelength is directed toward the exit side of the filter (which acts as a mirror) at such an angle that the second beam is reflected colinear with the first beam and superimposed on it. This process of superimposing the laser beams continues as each laser beam from the laser diodes is added to form a combined laser beam.
    Type: Grant
    Filed: November 10, 1986
    Date of Patent: April 18, 1989
    Assignee: The United States of America as represented by the Secretary of the Air Force
    Inventor: William L. Casey
  • Patent number: 4823351
    Abstract: For fast variation of the wavelengths of lasers, a rotating chopper mirror is provided in the laser resonator. This mirror alternately transmits the light to a grating or deflects it to at least a second grating or to a second mirror. Instead of a chopper mirror, an oscillating mirror can be used, by means of which the beam can be directed to a grating. The oscillating mirror is moved at constant frequency, but with variable amplitude.
    Type: Grant
    Filed: September 4, 1986
    Date of Patent: April 18, 1989
    Assignee: Battelle-Institut e.V.
    Inventors: Martin Endemann, Hansjuergen Hoeffgen
  • Patent number: 4817109
    Abstract: An external resonator type semiconductor laser apparatus comprising a semiconductor laser device, a reflector positioned behind said laser device in a manner to face the light-emitting rear facet of said laser device, and a photodetector, for detecting the optical output of said laser device, positioned backward of said reflector, wherein a part of the laser light from said light-emitting rear facet is reflected by said reflector and the reflected light is then incident to said photodetector.
    Type: Grant
    Filed: December 4, 1986
    Date of Patent: March 28, 1989
    Assignee: 501 Sharp Kabushiki Kaisha
    Inventors: Nobuybuki Miyauchi, Osamu Yamamoto, Hiroshi Hayashi, Saburo Yamamoto, Shigeki Maei
  • Patent number: 4809293
    Abstract: An optical component of a laser, of the type including a hot gas plasma region, a cold gas region, and producing large photon fluxes, includes an optical element and a coating means on a surface of the optical element exposed to the photon fluxes. The coating means is comprised of a material adapted to minimize photoreduction of the optical element induced by exposure to the photon fluxes. Optical elements of the present invention include windows, birefringent plates, intracavity lenses, polarizers and mirrors. The coating means includes a material selected from the group comprising Al.sub.2 O.sub.3, BeO, Y.sub.2 O.sub.3, MgO, B.sub.2 O.sub.3, Sc.sub.2 O.sub.3, LiF, NdF.sub.3, ThF.sub.4, Na.sub.3 AlF.sub.6, and mixtures thereof.
    Type: Grant
    Filed: June 5, 1987
    Date of Patent: February 28, 1989
    Assignee: Spectra-Physics, Inc.
    Inventors: Gary W. DeBell, David L. Wright, Kenneth A. Ruddock, Alan B. Petersen, Lee R. Carlson, Marc K. Von Gunten
  • Patent number: 4804747
    Abstract: (i) A compound of the formula: ##STR1## wherein R is H, a metal or a group containing a tetravalent N atom;X is S, O, ##STR2## R.sup.1 is NO.sub.2, CN or COOY; Y is H, C.sub.1-4 -alkyl, a metal or a group containing a tetravalent N atom;R.sup.2 and R.sup.3 are each independently H or a non-hydrophilic aliphatic or cycloaliphatic group containing up to 30 carbon atoms;R.sup.4 and R.sup.5 are each independently H or a non-hydrophilic aliphatic or cycloaliphatic group containing up to 30 carbon atoms; andR.sup.6 and R.sup.7 are each independently H or a non-hydrophilic group containing up to 4 carbon atoms; orR.sup.4 and R.sup.6 together comprise ring fused to Ring A and R.sup.5 and R.sup.7 are as hereinbefore defined; orR.sup.5 and R.sup.7 together comprise ring fused to Ring A and R.sup.4 and R.sup.6 are as hereinbefore defined; orR.sup.2 and R.sup.4 together with the N atom to which R.sup.2 is attached form a ring fused to Ring A and R.sup.3 and R.sup.5 are as hereinbefore defined; orR.sup.3 and R.sup.
    Type: Grant
    Filed: October 16, 1986
    Date of Patent: February 14, 1989
    Assignee: Imperial Chemical Industries PLC
    Inventors: Simon Allen, Paul F. Gordon, Richard A. Hann
  • Patent number: 4803696
    Abstract: A laser is disclosed which uses a curved spatial grating in either its reflective or output regions, or both, or distributed throughout the laser resonator, to produce an unstable optical reflection pattern which fills the resonating cavity more efficiently than in prior devices. Various combinations of different grating curvatures are disclosed. The invention is particularly adapted to semiconductor lasers.
    Type: Grant
    Filed: June 30, 1987
    Date of Patent: February 7, 1989
    Assignee: Hughes Aircraft Company
    Inventors: David M. Pepper, Richard R. Craig
  • Patent number: 4803694
    Abstract: To generate a laser beam of significantly higher quality and high output power without damaging the output coupler (mirror), a novel stable optical laser resonator includes, in particular, a retro-reflector having an aspherical concave mirror for correcting intracavity wavefront aberrations induced when the laser beam travels through the lasing medium. The optimal surface constants of the geometry of the aspherical mirror are determined by an optical interferometry technique, an geometrical ray-tracing technique, and computer-aided ray tracing technique.
    Type: Grant
    Filed: July 8, 1987
    Date of Patent: February 7, 1989
    Assignee: Amada Company, Limited
    Inventors: Chun-Sheu Lee, Stanley L. Ream
  • Patent number: 4796262
    Abstract: An optical resonator for a power laser comprises between one of a pair of totally reflecting mirros flanking the end of a pumped active element such as a Nd:YAG crystal, a passive Q switch and between the passive Q switch and the active element, a polarizer which reflects the output transversely to the optical axis of the reflecting beams of the cavity. A phase shifter is provided between the polarizer and the approximal end of the active element. This system prevents the full output energy from impinging upon the passive Q switch so that the passive Q switch or other low-damage-threshold optical elements associated therewith do not have to take the full power.
    Type: Grant
    Filed: March 17, 1986
    Date of Patent: January 3, 1989
    Assignee: Selenia Industrie Elettroniche Associate SpA
    Inventors: Glauco B. Michelangeli, Michele De Maria, Giampiero Giuliani
  • Patent number: 4794617
    Abstract: An external optical resonator for use with a semiconductor laser has a high selectivity and phase steepness for the input reflection factor in the region of the resonance frequency and is highly stable. An optical directional coupler is coupled to the semiconductor laser and two gates of the coupler are connected to one another by a radiation transmission path for externally transmitting radiant power. The coupling factor of the directional coupler is selected such that the radiation coupled into one waveguide of the coupler is nearly completely coupled over to the other waveguide of the coupler. Nearly complete suppression of all secondary modes is obtained by using a wavelength selective directional coupler in place of a broad band directional coupler.
    Type: Grant
    Filed: September 12, 1986
    Date of Patent: December 27, 1988
    Assignee: Siemens Aktiengesellschaft
    Inventor: Georg Boeck
  • Patent number: 4787092
    Abstract: The invention relates to a laser utilizing a negative branch unstable cavity resonator, comprising two opposed and aligned reflecting mirrors and a baffle aligned with the optic axis of the cavity and located in close proximity to the effective focal point of at least one of the mirrors as determined by the influence of the cavity's remaining optical components. The baffle is provided with an aperture of size such as to stop down the focal spot at its first minimum level of luminous intensity from center. The laser beam, which is out-coupled by conventional techniques, possesses optimum intensity-distribution spatial characteristics in space, and can be focused almost to the diffraction limits.
    Type: Grant
    Filed: February 23, 1988
    Date of Patent: November 22, 1988
    Assignee: Quanta System S.R.L.
    Inventors: Pier G. Gobbi, Giancarlo Reali
  • Patent number: 4785462
    Abstract: A dynamically one-mode semiconductor laser having a laser diode with a coupled external resonator includes a resonator mirror disposed opposite a light emitting face of the laser diode and a collimation optics between the diode and the resonator mirror. The collimation optics includes a refractive hemispherical micro-lens having flat side applied to the resonator mirror which is manufactured by fusing a small drop of glass onto the resonator mirror.
    Type: Grant
    Filed: August 18, 1986
    Date of Patent: November 15, 1988
    Assignee: Siemens Aktiengesellschaft
    Inventor: Rudolf Keil
  • Patent number: 4761789
    Abstract: Method and apparatus for cooling a slab-geometry solid state laser medium wherein at least one of the front or rear surfaces of the laser medium is in contact with a glass cover, and a coolant is passed over the outside of the glass cover.
    Type: Grant
    Filed: July 31, 1986
    Date of Patent: August 2, 1988
    Assignee: Amada Engineering & Service Co., Inc.
    Inventor: Kenneth A. Fukae
  • Patent number: 4757512
    Abstract: A device and process using Ag.sub.2 O.sub.2 and Ag.sub.2 O.sub.3 as a catalyst for oxidizing carbon monoxide to form CO.sub.2 at temperatures between 20.degree. C. and 120.degree. C. This has particular application to CO.sub.2 lasers. In one CO.sub.2 laser embodiment, silver is distributed on the walls of the discharge volume. The silver is divided to form electrically isolated islands to prevent interference with the discharge. After an activation process, energetic forms of oxygen, such as atomic oxygen, reacts with the silver to form endothermic silver oxides which can be easily reduced by CO. In another embodiment, the Ag.sub.2 O.sub.2 or Ag.sub.2 O.sub.3 catalyst is used in a convective flow laser.
    Type: Grant
    Filed: February 18, 1987
    Date of Patent: July 12, 1988
    Inventor: John A. Macken
  • Patent number: 4756000
    Abstract: A device and process using a gold as a catalyst for oxidizing carbon monoxide to form CO.sub.2 at ambient temperatures. This has particular application to CO.sub.2 lasers. In one CO.sub.2 laser embodiment, gold is distributed on the walls of the discharge volume. The gold is divided to form electrically isolated islands to prevent interference with the discharge. Energetic forms of oxygen, such as atomic oxygen reacts with CO on the gold catalyst. In another embodiment, the gold catalyst is used in a convective flow laser.
    Type: Grant
    Filed: February 18, 1987
    Date of Patent: July 5, 1988
    Inventor: John A. Macken