A method for laser welding a metal foil stack to a metal substrate includes clamping the foil stack against a support surface of a substrate and irradiating the stack with a beam of laser pulses to weld the foils to the substrate. The beam is a composite beam including a center beam and a surrounding annular beam. An initial series of the laser pulses are incident on the stack at mutually distinct locations on a top surface of the stack, and a subsequent series of the laser pulses are incident on the stack at mutually distinct locations on a side of the stack. The resulting weld nuggets penetrate deeply into the stack, with an average penetration depth that exceeds an average pitch between the weld nuggets. The method is capable of welding more than 100 foils to the substrate. Welded assemblies have been demonstrated to withstand large shear forces.
A laser frequency conversion system with ultraviolet-damage mitigation includes a nonlinear crystal for frequency converting a laser beam, and a one-dimensional beam expander arranged to receive the laser beam from the nonlinear crystal and expand a first transverse dimension of the laser beam. This expansion protects subsequent optical elements from ultraviolet damage. To mitigate ultraviolet damage to the nonlinear crystal and the beam expander, the system also includes one or more translation stages configured to translate the nonlinear crystal and the beam expander along a translation direction that is orthogonal to the first transverse dimension of the laser beam and non-parallel to a propagation direction of the laser beam through the nonlinear crystal and the beam expander.
A see-through near-eye display device includes an image source configured to emit light conveying an image, a one-dimensional waveguide made of a crystalline material transmissive to visible light and arranged to receive and guide the light emitted by the image source, and a first grating disposed on or in the waveguide. The first grating is configured to couple out of the waveguide at least a portion of the light from the image source after having been guided by the waveguide to the first grating. Several particularly advantageous crystalline waveguide materials are disclosed, which exhibit a high refractive index and high transparency in the visible spectrum. In one class of embodiments, the crystalline waveguide material is based on a bismuth germanium oxide crystal or a bismuth silicon oxide crystal, optionally with substitutions and/or doping. The crystalline waveguide material may be of the form of Bi12Ge1-x-ySixTiyO20, with or without further dopants.
G02B 1/02 - Optical elements characterised by the material of which they are madeOptical coatings for optical elements made of crystals, e.g. rock-salt, semiconductors
A method laser cuts and laser pre-welds a stack of metal foils in a single laser process. The method includes clamping together the stack of metal foils, and irradiating the clamped stack with a laser beam to complete a cut through the entire stack and, while cutting the stack, form a weld joint joining the metal foils together at the cut. Subsequently, the cut and pre-welded stack of metal foils may be laser welded to a metal substrate that is significantly thicker than individual foils. The method may be applied to stacks of anode and cathode foils in electrochemical batteries, such as lithium-ion batteries.
B23K 28/02 - Combined welding or cutting procedures or apparatus
B23K 37/04 - Auxiliary devices or processes, not specially adapted for a procedure covered by only one of the other main groups of this subclass for holding or positioning work
A Q-switched gas laser apparatus with bivariate pulse equalization includes a gas laser, a sensor, and an electronic circuit. A Q-switch that switches the laser resonator between high-loss and low-loss states to generate a pulsed laser beam. The sensor obtains a measurement of the pulsed laser beam indicative of the laser pulse energy. The electronic circuitry operates the Q-switch to (a) repeatedly switch the laser resonator between the high-loss and low-loss states to set a repetition rate of laser pulses of the pulsed laser beam, (b) adjust a loss level of the low-loss state, based on the pulse energy measurement, to achieve a target laser pulse energy, and (c) adjust a duration of the low-loss state to achieve a target laser pulse duration. By adjusting both pulse energy and duration, uniform pulse energy and, if desired, uniform pulse duration are achieved over a wide range of repetition rates.
An actively cooled end-pumped solid-state laser gain device includes a bulk solid-state gain medium. An input-end of the gain medium receives a pump laser beam incident thereon and propagating in the direction toward an opposite output-end. The metal foil is disposed over a face of the gain medium extending between the input- and output-ends. A housing cooperates with the metal foil to form a coolant channel on the face the gain medium. The coolant channel has an inlet and an outlet configured to conduct a flow of coolant along the metal foil from the input-end towards the output-end. The metal foil is secured between the gain medium and portions of the housing running adjacent to the coolant channel. The metal foil provides a reliable thermal contact and imparts little or no stress on the bulk gain medium.
H01S 3/042 - Arrangements for thermal management for solid state lasers
H01S 3/0941 - Processes or apparatus for excitation, e.g. pumping using optical pumping by coherent light of a semiconductor laser, e.g. of a laser diode
A thermally actuated adaptive optic includes a base, a reflector, and a plurality of actuators coupled therebetween. The reflector has a light-receiving front surface, and a back surface facing the base. Each actuator includes a bracket rigidly bonded to the reflector at a perimeter of the reflector, and an inner rod and an outer rod. Each rod is rigidly connected between the bracket and the base, with the inner rod being closer to a center of the reflector. The length of each rod is temperature dependent. In another adaptive optic, the rods are instead bonded directly to the reflector. This adaptive optic may be modified to implement an integrally formed, thermally actuated support. The disclosed adaptive optics are suitable for use in laser systems, allow for significant cost savings over piezoelectric devices, provide a reflective area free of surface-figure perturbations caused by the actuator-interfaces, and are relatively simple to manufacture.
G02B 7/182 - Mountings, adjusting means, or light-tight connections, for optical elements for prismsMountings, adjusting means, or light-tight connections, for optical elements for mirrors for mirrors
G02B 7/18 - Mountings, adjusting means, or light-tight connections, for optical elements for prismsMountings, adjusting means, or light-tight connections, for optical elements for mirrors
8.
OPTOMECHANICAL ASSEMBLIES FOR TEMPERATURE-ROBUST LASER BEAM COMBINATION AND DELIVERY
An optomechanical assembly for temperature-robust laser beam processing includes a baseplate and an optics plate. The baseplate includes a source area for accommodating a source of the laser beam, and a light-processing area located away from the source area and including first and second anchor points. The optics plate is disposed in the light-processing area and includes first and second portions and a flexible coupling interconnecting the first and second portions. The first and second portions are fixed to the baseplate at the first and second anchor points, respectively. The flexible coupling allows for a thermally-induced change in distance between the first and second anchor points in the presence of dissimilar thermal expansion of the optics plate and the baseplate. The assembly further includes a series of optical elements for manipulating a laser beam from the laser source. Each of the optical elements is rigidly bonded to the first portion.
An ultrashort-pulse compressor includes (a) one or more bulk-optics intersecting a propagation path of an ultrashort-pulsed laser beam multiple times to spectrally broaden a pulse of the laser beam during each of multiple passes through the bulk-optic(s), (b) one or more dispersive optics for compressing a duration of the pulse after each of the multiple passes, and (c) a plurality of focusing elements for focusing the laser beam between the multiple passes. Propagation distances between the bulk-optic(s) and the focusing elements are detuned from imaging such that a spot size of the laser beam, at the bulk-optic(s), is greater at each successive one of the multiple passes. As the laser beam propagates through this compressor, each laser pulse is alternatingly spectral broadened and temporally compressed. The increasing spot size of the laser, for each pass, helps prevent optical damage, run-away self-focusing, and other undesirable outcomes.
A pulsed third-harmonic laser system includes a pulsed laser, an extra-cavity nonlinear crystal, and an intracavity nonlinear crystal. The pulsed laser generates fundamental laser pulses and couples out a portion of each fundamental laser pulse out of the laser resonator to undergo second-harmonic-generation in the extra-cavity nonlinear crystal. Resulting second-harmonic laser pulses are directed back into the laser resonator and mixes with the fundamental laser pulses in the intracavity nonlinear crystal to generate third-harmonic laser pulses. The pulsed third-harmonic laser system thus maintains a non-zero output coupling efficiency regardless of the efficiency of the second-harmonic-generation stage, while the third-harmonic-generation stage benefits from the intracavity power of the fundamental laser pulses.
H01S 3/00 - Lasers, i.e. devices using stimulated emission of electromagnetic radiation in the infrared, visible or ultraviolet wave range
H01S 3/11 - Mode lockingQ-switchingOther giant-pulse techniques, e.g. cavity dumping
H01S 3/108 - Controlling the intensity, frequency, phase, polarisation or direction of the emitted radiation, e.g. switching, gating, modulating or demodulating by controlling devices placed within the cavity using non-linear optical devices, e.g. exhibiting Brillouin or Raman scattering
A method for laser keyhole welding is disclosed to weld two pieces together made of a metal alloy. The method independently adjusts power in a focused center beam and power in a concentric focused annular beam. At the termination of a weld, the power of the annular beam is reduced, motion of the focused beams is stopped, the power of the center beam is increased, and the power of both beams is initially ramped down rapidly and then ramped down slowly. Increasing the power of the center beam equalizes the temperature of both pieces prior to solidification and cooling at the termination of the weld. An additional pulse of power may be applied to prevent the formation of defects or to erase any defects.
2) or carbon monoxide (CO) gas laser includes two electrodes, which have passivated surfaces, within a sealed housing. Features in a ceramic slab or a ceramic cylinder located between the electrodes define a gain volume. Surfaces of the ceramic slab or the ceramic cylinder are separated from the passivated surfaces of the electrodes by small gaps to prevent abrasion thereof. Reducing compressive forces that secure these components within the housing further reduces abrasion, thereby extending the operational lifetime of the gas laser.
An optical parametric chirped-pulse amplifier includes first and second optical parametric amplifier stages that successively amplify a stretched signal beam. A pulsed laser provides a fundamental beam. The second amplifier stage is pumped by the full power of a second-harmonic beam that is generated from the fundamental beam. A residual fundamental beam is used to generate another second-harmonic beam that pumps the first amplifier stage.
A wavelength sensor for wavelength stabilization of a laser beam includes an etalon placed in the laser beam and tilted with respect to the laser beam. Reflected beams from the etalon form an interference pattern on a segmented photodetector having two detector segments. Output signals from the two detector segments are used to derive an error signal for a closed control loop to effect the wavelength stabilization.
A fiber laser producing a beam of ultrashort laser pulses at a repetition rate greater than 200 MHz includes a linear fiber resonator and a fiber branch. Ultrashort laser pulses are generated by passive mode-locking and circulate within the linear fiber resonator. Each circulating laser pulse is split into a portion that continues propagating in the linear fiber resonator and a complementary portion that propagates through the fiber branch and is then returned to the linear fiber resonator. The optical length of the linear fiber resonator is an integer multiple of the optical length of the fiber branch. The repetition rate of the ultrashort laser pulses is the reciprocal of the propagation time of the laser pulses through the fiber branch.
H01S 3/08 - Construction or shape of optical resonators or components thereof
H01S 3/10 - Controlling the intensity, frequency, phase, polarisation or direction of the emitted radiation, e.g. switching, gating, modulating or demodulating
H01S 3/1055 - Controlling the intensity, frequency, phase, polarisation or direction of the emitted radiation, e.g. switching, gating, modulating or demodulating by controlling the mutual position or the reflecting properties of the reflectors of the cavity one of the reflectors being constituted by a diffraction grating
An apparatus includes a beam source, beam forming optics, a first focusing lens having a focal length, a second focusing lens having a focal length similar to the focal length of the first lens, and a lens translator configured to move the second lens transversely relative to the beam forming optics and to the first lens, and thereby move the elongated focus transversely. In some embodiments, the beam forming optics are positioned between the beam source and the first focusing lens, the first focusing lens is positioned between the beam forming optics and the second focusing lens, and the beam forming optics, the first focusing lens, and the second focusing lens are arranged to receive a beam of laser radiation from the beam source and to form the beam into an elongated focus.
A method for laser keyhole welding of metal alloys is disclosed. The method independently adjusts power in a focused center beam and power in a concentric focused annular beam. At the termination of a weld, the power in the center beam is initially ramped up and then ramped down, while the power in the annular beam is ramped down. Increasing the power in the center beam enables a controlled and prolonged contraction of the keyhole and melt pool, thereby preventing undesirable cracking.
An apparatus for cutting brittle material comprises an aspheric focusing lens, an aperture, and a laser-source generating a beam of pulsed laser-radiation. The aspheric lens and the aperture form the beam of pulsed laser-radiation into an elongated focus having a uniform intensity distribution along the optical axis of the aspheric focusing lens. The elongated focus extends through the full thickness of a workpiece made of a brittle material. The workpiece is cut by tracing the optical axis along a cutting line. Each pulse or burst of pulsed laser-radiation creates an extended defect through the full thickness of the workpiece.
B23K 26/00 - Working by laser beam, e.g. welding, cutting or boring
B23K 26/53 - Working by transmitting the laser beam through or within the workpiece for modifying or reforming the material inside the workpiece, e.g. for producing break initiation cracks
B23K 26/066 - Shaping the laser beam, e.g. by masks or multi-focusing by means of optical elements, e.g. lenses, mirrors or prisms by using masks
B23K 26/0622 - Shaping the laser beam, e.g. by masks or multi-focusing by direct control of the laser beam by shaping pulses
B23K 26/08 - Devices involving relative movement between laser beam and workpiece
B23K 26/402 - Removing material taking account of the properties of the material involved involving non-metallic material, e.g. isolators
C03B 33/02 - Cutting or splitting sheet glassApparatus or machines therefor
G02B 27/09 - Beam shaping, e.g. changing the cross-sectioned area, not otherwise provided for
2) greater of than 50 in one transverse axis and greater than 20 in another transverse axis. The output beams are combined and formed into a line-beam that is projected on a substrate being annealed. Each output beam contributes to the length of the line-beam.
H01S 3/109 - Frequency multiplication, e.g. harmonic generation
B23K 26/00 - Working by laser beam, e.g. welding, cutting or boring
B23K 26/0622 - Shaping the laser beam, e.g. by masks or multi-focusing by direct control of the laser beam by shaping pulses
B23K 26/064 - Shaping the laser beam, e.g. by masks or multi-focusing by means of optical elements, e.g. lenses, mirrors or prisms
B23K 26/354 - Working by laser beam, e.g. welding, cutting or boring for surface treatment by melting
H01S 3/06 - Construction or shape of active medium
H01S 3/08 - Construction or shape of optical resonators or components thereof
H01S 3/094 - Processes or apparatus for excitation, e.g. pumping using optical pumping by coherent light
H01S 3/0941 - Processes or apparatus for excitation, e.g. pumping using optical pumping by coherent light of a semiconductor laser, e.g. of a laser diode
H01S 3/115 - Q-switching using intracavity electro-optic devices
A carbon dioxide gas-discharge slab-laser is assembled in a laser-housing. The laser-housing is formed from a hollow extrusion. An interior surface of the extrusion provides a ground electrode of the laser. Another live electrode is located within the extrusion, electrically insulated from and parallel to the ground electrode, forming a discharge-gap of the slab-laser. The electrodes are spaced apart by parallel ceramic strips. Neither the extrusion, nor the live electrode, include fluid coolant channels. The laser-housing is cooled by fluid-cooled plates attached to the outside thereof.
A laser-radiation sensor includes a copper substrate on which is grown an oriented polycrystalline buffer layer surmounted by an oriented polycrystalline sensor-element of an anisotropic transverse thermoelectric material. An absorber layer, thermally connected to the sensor-element, is heated by laser-radiation to be measured and communicates the heat to the sensor-element, causing a thermal gradient across the sensor-element. Spaced-apart electrodes in electrical contact with the sensor-element sense a voltage corresponding to the thermal gradient as a measure of the incident laser-radiation power.
G01J 1/42 - Photometry, e.g. photographic exposure meter using electric radiation detectors
H01L 31/0368 - SEMICONDUCTOR DEVICES NOT COVERED BY CLASS - Details thereof characterised by their semiconductor bodies characterised by their crystalline structure or particular orientation of the crystalline planes including polycrystalline semiconductors
G01J 5/12 - Radiation pyrometry, e.g. infrared or optical thermometry using electric radiation detectors using thermoelectric elements, e.g. thermocouples
An apparatus for generating visible light including a laser source emitting a fundamental beam, an optically nonlinear crystal, and a seed source emitting a seed beam. The optically nonlinear crystal receives the fundamental beam. The fundamental beam propagates in the nonlinear crystal at a first phase-matching angle for second-harmonic generation. A portion of the fundamental beam is converted into a second-harmonic beam that propagates in the nonlinear crystal at the first phase-matching angle for optical parametric generation. The seed source emits a seed beam having a wavelength longer than the second-harmonic beam. The seed beam is directed into the nonlinear crystal and propagates at a second phase-matching angle for the optical parametric amplification. A portion of the second-harmonic beam is converted into a signal beam at the seed wavelength and an idler beam by the optical parametric amplification.
A third-harmonic conversion arrangement includes a second-harmonic generating crystal and a third-harmonic generating crystal arranged in a polarization loop. The polarization loop, which includes a plurality of mirrors, a polarization-selective reflector, and a polarization rotator, causes plane-polarized fundamental-wavelength radiation being converted to make two passes through the crystals in orthogonally-opposed polarization orientations.
A laser master-oscillator power-amplifier (MOPA) is operated to provide successive bursts of ultrashort pulses. The pulse-bursts are selected by an optical modulator from a pulse train delivered by the master oscillator prior to amplification in the power amplifier. The optical modulator has a selectively variable transmission specified by an analog voltage signal having a stepped waveform. The voltage signal is delivered by a sequentially-switched parallel switch-array connected in parallel with a parallel DAC having multiple parallel DC voltage outputs corresponding to steps of the stepped waveform.
H01S 3/106 - Controlling the intensity, frequency, phase, polarisation or direction of the emitted radiation, e.g. switching, gating, modulating or demodulating by controlling devices placed within the cavity
A carbon dioxide gas-discharge slab-laser is assembled in a laser-housing. The laser-housing is formed from a hollow extrusion. An interior surface of the extrusion provides a ground electrode of the laser. Another live electrode is located within the extrusion, electrically insulated from and parallel to the ground electrode, forming a discharge-gap of the slab-laser. The electrodes are spaced apart by parallel ceramic strips. Neither the extrusion, nor the live electrode, include any direct fluid-cooling means. The laser-housing is cooled by fluid-cooled plates attached to the outside thereof.
An aluminum covered with an anodically formed aluminum oxide layer is marked by repeated bursts of two or more individual laser pulses. The intensity of the individual pulses in the bursts is kept below a level experimentally determined to compromise the integrity of the aluminum oxide layer. The collective fluence in a burst is sufficient to mark the aluminum, but not sufficient to compromise the integrity of the oxide layer.
B23K 26/06 - Shaping the laser beam, e.g. by masks or multi-focusing
B23K 26/0622 - Shaping the laser beam, e.g. by masks or multi-focusing by direct control of the laser beam by shaping pulses
B23K 26/356 - Working by laser beam, e.g. welding, cutting or boring for surface treatment by shock processing
B23K 26/359 - Working by laser beam, e.g. welding, cutting or boring for surface treatment by providing a line or line pattern, e.g. a dotted break initiation line
An anamorphic three-element objective lens projects a plurality of beams of different wavelengths and different diameters into an elongated focal spot in a working-plane. In one transverse direction of the lens, the beams are tightly focused with equal beam-waist widths in the working-plane, defining a height of the focal spot. In another transverse direction, the different beams are focused progressively beyond the working-plane such that the beams have a common beam-width in the working-plane, thereby defining a width of the focal spot.
G02B 27/14 - Beam splitting or combining systems operating by reflection only
G02B 13/14 - Optical objectives specially designed for the purposes specified below for use with infrared or ultraviolet radiation
G02B 27/18 - Optical systems or apparatus not provided for by any of the groups , for optical projection, e.g. combination of mirror and condenser and objective
G02B 23/04 - Telescopes, e.g. binocularsPeriscopesInstruments for viewing the inside of hollow bodiesViewfindersOptical aiming or sighting devices involving prisms or mirrors for the purpose of beam splitting or combining, e.g. fitted with eyepieces for more than one observer
G02B 9/16 - Optical objectives characterised both by the number of the components and their arrangements according to their sign, i.e. + or – having three components only arranged + – + all the components being simple
G02B 27/09 - Beam shaping, e.g. changing the cross-sectioned area, not otherwise provided for
G01N 15/14 - Optical investigation techniques, e.g. flow cytometry
A61B 5/00 - Measuring for diagnostic purposes Identification of persons
Apparatus for distance gauging in laser material processing includes a source of laser-radiation, an electrically-conductive focusing assembly, a constant-current source, and a voltmeter. The focusing assembly focuses laser-radiation towards an electrically conductive workpiece being processed. The focusing assembly and the workpiece form a capacitive sensor. The constant current source provides a constant electrical current to the focusing assembly for a constant time. The focusing assembly and the workpiece are separated by a distance that is proportional to a change in voltage measured on the focusing assembly during the constant time.
B23K 26/04 - Automatically aligning, aiming or focusing the laser beam, e.g. using the back-scattered light
G01B 7/14 - Measuring arrangements characterised by the use of electric or magnetic techniques for measuring distance or clearance between spaced objects or spaced apertures
B23K 26/38 - Removing material by boring or cutting
29.
High power sub-400 femtosecond MOPA with solid-state power amplifier
Laser-apparatus includes a fiber-MOPA arranged to deliver amplified seed optical pulses having a wavelength of about 1043 nanometers to a multi-pass ytterbium-doped yttrium aluminum garnet solid-state optical amplifier for further amplification.
A fiber-laser includes a gain-fiber in a laser-resonator. A polarizer is located in the laser-resonator at an end thereof, causing the output of the fiber-laser to be linearly polarized. A wavelength-selective element is also included in the laser-resonator for selecting an output wavelength of the fiber-laser from within a gain-bandwidth of the gain-fiber.
An intra-cavity frequency-tripled OPS laser has a laser-resonator including two optically nonlinear crystals arranged for type-I frequency conversion. One of the crystals generates horizontally polarized second-harmonic radiation from vertically plane-polarized fundamental-wavelength radiation circulating in the laser-resonator. A birefringent filter is located between the optically nonlinear crystals. The birefringent filter selects the fundamental-wavelength, establishes the vertical polarization-orientation, and selectively rotates the polarization-orientation of the second-harmonic radiation from horizontal to vertical. The vertically polarized fundamental and second-harmonic radiations are type-I sum-frequency mixed by the other optically nonlinear crystal.
H01S 3/10 - Controlling the intensity, frequency, phase, polarisation or direction of the emitted radiation, e.g. switching, gating, modulating or demodulating
H01S 3/109 - Frequency multiplication, e.g. harmonic generation
H01S 3/081 - Construction or shape of optical resonators or components thereof comprising three or more reflectors
H01S 3/13 - Stabilisation of laser output parameters, e.g. frequency or amplitude
H01S 3/08 - Construction or shape of optical resonators or components thereof
H01S 3/0941 - Processes or apparatus for excitation, e.g. pumping using optical pumping by coherent light of a semiconductor laser, e.g. of a laser diode
An apparatus for cutting brittle material comprises an aspheric focusing lens, an aperture, and a laser-source generating a beam of pulsed laser-radiation. The aspheric lens and the aperture form the beam of pulsed laser-radiation into an elongated focus having a uniform intensity distribution along the optical axis of the aspheric focusing lens. The elongated focus extends through the full thickness of a workpiece made of a brittle material. The workpiece is cut by tracing the optical axis along a cutting line. Each pulse or burst of pulsed laser-radiation creates an extended defect through the full thickness of the workpiece.
B23K 26/00 - Working by laser beam, e.g. welding, cutting or boring
B23K 26/53 - Working by transmitting the laser beam through or within the workpiece for modifying or reforming the material inside the workpiece, e.g. for producing break initiation cracks
B23K 26/066 - Shaping the laser beam, e.g. by masks or multi-focusing by means of optical elements, e.g. lenses, mirrors or prisms by using masks
B23K 26/0622 - Shaping the laser beam, e.g. by masks or multi-focusing by direct control of the laser beam by shaping pulses
B23K 26/08 - Devices involving relative movement between laser beam and workpiece
B23K 26/402 - Removing material taking account of the properties of the material involved involving non-metallic material, e.g. isolators
C03B 33/02 - Cutting or splitting sheet glassApparatus or machines therefor
G02B 27/09 - Beam shaping, e.g. changing the cross-sectioned area, not otherwise provided for
A mirror is used to form a beam of laser-radiation having a uniform intensity distribution from a beam of laser-radiation having a non-uniform intensity distribution. The mirror has a reflective surface that has a compound shape, which is two inclined surfaces joined by a rounded apex. The compound-mirror is achromatic and can form a uniform intensity distribution from a polychromatic beam of laser-radiation. The uniform intensity distribution may be an isotropic distribution or a flat-top distribution in a plane. The non-uniform intensity distribution may be a Gaussian distribution from a laser source.
A method of delivering a beam of laser-radiation to a workpiece for processing the workpiece comprises transmitting the beam twice through an inactive acousto-optic modulator (AOM) crystal in opposite zero-order directions of the AOM at separate locations on the AOM crystal, before delivering the beam to the workpiece. When laser-radiation is to be blocked from reaching the workpiece, the AOM is activated.
A housing for an optically pumped semiconductor (OPS) laser resonator is terminated at one end thereof by an OPS-chip. The laser resonator is assembled on a platform with the OPS-chip at one end of the platform. The platform is fixedly attached to a baseplate at the OPS-chip end of the platform. The remainder of the platform extends over the baseplate with a gap between the platform and the baseplate. A pump-laser is mounted directly on the baseplate and delivers pump radiation to the OPS-chip.
In a flow cytometer, an objective lens for focusing an input laser-radiation beam including at least four different laser-radiation wavelengths in a common plane includes only three singlet lens-elements. Two of the elements are cylindrical elements arranged as a cylindrical telescope for shaping and reducing the size of the input laser-beam. The third element is a spherical element arranged to focus the reduced size beam in the common plane. In one example, all three elements are made from the same optical material.
G02B 13/18 - Optical objectives specially designed for the purposes specified below with lenses having one or more non-spherical faces, e.g. for reducing geometrical aberration
G01N 15/14 - Optical investigation techniques, e.g. flow cytometry
G02B 9/16 - Optical objectives characterised both by the number of the components and their arrangements according to their sign, i.e. + or – having three components only arranged + – + all the components being simple
G02B 27/09 - Beam shaping, e.g. changing the cross-sectioned area, not otherwise provided for
Apparatus for generating a line-beam includes a diode-laser bar, a linear micro-lens array, and a plurality of lenses spaced apart and arranged along an optical axis. The linear micro-lens array and the lenses shape laser-radiation emitted by the diode-laser bar to form a uniform line-beam in an illumination plane. The lenses project a far-field image of the diode-laser bar onto an image plane proximate to the illumination plane. The diode-laser bar is rotated from parallel alignment with the linear micro-lens array for providing uniform line-beam illumination over a range of locations along the optical axis.
H01S 3/08 - Construction or shape of optical resonators or components thereof
G02B 27/20 - Optical systems or apparatus not provided for by any of the groups , for optical projection, e.g. combination of mirror and condenser and objective for imaging minute objects, e.g. light-pointer
G02B 27/09 - Beam shaping, e.g. changing the cross-sectioned area, not otherwise provided for
A diode-laser bar assembly comprises a diode-laser bar mounted onto a cooler by way of an electrically-insulating submount. A laminated connector is provided that includes two electrically-conducting sheets bonded to opposite sides on an electrically-insulating sheet. An electrical insulator is located between the laminated connector and the cooler. One electrically-conducting sheet is connected to n-side of the diode-laser bar and the other electrically-conducting sheet is connected to p-side of the diode-laser bar.
H01L 23/44 - Arrangements for cooling, heating, ventilating or temperature compensation the complete device being wholly immersed in a fluid other than air
A cooler for diode-laser bars comprises a machined base including a water-input plenum and a water-output plenum, and a top plate on which the diode-laser bars can be mounted. A stack of three etched plates is provided between the base and first plate. The stack of etched plates is configured to provide a five longitudinally spaced-apart rows of eight laterally spaced-apart cooling-channels connected to the water-input and water-output plenums. Water flows in the cooling-channels and in thermal contact with the first plate.
H01L 23/473 - Arrangements for cooling, heating, ventilating or temperature compensation involving the transfer of heat by flowing fluids by flowing liquids
H01S 5/40 - Arrangement of two or more semiconductor lasers, not provided for in groups
Optical output beams from a vertical stack of diode-laser bars are focused by a simple focusing lens on an optical axis of the lens. The optical output beams from outlying diode-laser bars in the vertical stack are tilted with respect to the optical axis of the focusing lens such that optical output from the whole vertical stack is brought to a common focus location on the optical axis of the focusing lens.
Provided are methods and systems for identification and analysis of materials and molecular structures. An apparatus for identification and analysis of materials and molecular structures may include a laser. The laser may, in turn, include an amplified spontaneous emission-suppressed single-frequency laser excitation source. The apparatus may further comprise a plurality of filters. The plurality of filters may include reflective volume holographic grating blocking filters. The apparatus may also comprise an optical unit and an optical spectrometer. The optical unit may be configured to deliver excitation energy to a sample substance and capture Raman signal scattering from the sample substance. The optical spectrometer may be disposed in a path of the Raman signal and configured to measure a spectrum of the Raman signal and generate a detection signal. Finally, the apparatus may comprise a processing unit configured to analyze the spectrum.
G01N 21/3581 - Investigating relative effect of material at wavelengths characteristic of specific elements or molecules, e.g. atomic absorption spectrometry using infrared light using far infrared lightInvestigating relative effect of material at wavelengths characteristic of specific elements or molecules, e.g. atomic absorption spectrometry using infrared light using Terahertz radiation
42.
Stackable electrically-isolated diode-laser bar assembly
A diode-laser assembly having an electrically isolated diode-laser bar on a cooled base-element is disclosed. The diode-laser bar is electrically isolated from the base-element and electrically isolated from any coolant water, thereby eliminating the need for de-ionized water and mitigating corrosion due to galvanic action. Multiple such diode-laser assemblies are stackable, with small bar-to-bar pitch, enabling a high-current and high-brightness diode-laser stack.
Laser-drilling apparatus includes a gas-discharge for laser emitting laser-radiation pulses, and two acousto-optic modulators (AOMs). The laser radiation pulses are characterized as having two temporal central portions between temporal leading and trailing edge portions. The AOMs are arranged to spatially separate the central temporal portions of the pulses from each other and from the leading and trailing edge portions of the pulses.
Provided are methods and systems for identification and analysis of materials and molecular structures. An apparatus for identification and analysis of materials and molecular structures may include a laser. The laser may, in turn, include an amplified spontaneous emission-suppressed single-frequency laser excitation source. The apparatus may further comprise a plurality of filters. The plurality of filters may include reflective volume holographic grating blocking filters. The apparatus may also comprise an optical unit and an optical spectrometer. The optical unit may be configured to deliver excitation energy to a sample substance and capture Raman signal scattering from the sample substance. The optical spectrometer may be disposed in a path of the Raman signal and configured to measure a spectrum of the Raman signal and generate a detection signal. Finally, the apparatus may comprise a processing unit configured to analyze the spectrum.
Systems and methods are provided herein. An exemplary system may include a laser source, the laser source having a laser center wavelength; at least one narrowband optical element receiving light emitted by the laser, the narrowband optical element having a filter center wavelength, the narrowband optical element being arranged such that the filter center wavelength is initially spectrally aligned with the laser center wavelength, the filter center wavelength changing in response to a temperature change such that the filter center wavelength is not substantially aligned with the laser center wavelength; and a passive adjustment mechanism coupled to the narrowband optical element, the passive adjustment mechanism including an actuator, the actuator moving in response to the temperature change, the actuator motion rotating the narrowband optical element, the rotation compensating for the temperature change such that the filter center wavelength and laser center wavelength remain spectrally aligned.
G03H 1/02 - Holographic processes or apparatus using light, infrared, or ultraviolet waves for obtaining holograms or for obtaining an image from themDetails peculiar thereto Details
An apparatus for generating and amplifying laser beams at approximately 1 micrometer wavelength is disclosed. The apparatus includes an ytterbium-doped gain-crystal pumped by an ytterbium fiber-laser. The fiber-laser enables a pump wavelength to be selected that minimizes heating of the gain-crystal. The apparatus can be configured for generating and amplifying ultra-fast pulses, utilizing the gain-bandwidth of ytterbium-doped gain-crystals.
H01S 3/23 - Arrangement of two or more lasers not provided for in groups , e.g. tandem arrangement of separate active media
H01S 3/10 - Controlling the intensity, frequency, phase, polarisation or direction of the emitted radiation, e.g. switching, gating, modulating or demodulating
H01S 3/11 - Mode lockingQ-switchingOther giant-pulse techniques, e.g. cavity dumping
H01S 3/094 - Processes or apparatus for excitation, e.g. pumping using optical pumping by coherent light
H01S 3/06 - Construction or shape of active medium
H01S 3/08 - Construction or shape of optical resonators or components thereof
H01S 3/081 - Construction or shape of optical resonators or components thereof comprising three or more reflectors
Laser-machining apparatus includes a carbon monoxide (CO) laser emitting a beam of laser-radiation having forty-four different wavelength components and optical elements for delivering the radiation to workpiece. An acousto-optic modulator is provided for modulating the beam on the workpiece. A birefringent plate is provided in the beam transported to the workpiece for randomly polarizing radiation incident on the workpiece. A minimum distance of the workpiece from the laser, and the number of different-wavelength components in the laser beam provides that no optical isolator is required for preventing feedback of radiation into the laser.
Plane-polarized laser-radiation from a laser-source is converted to circularly polarized radiation by a quarter-wave plate. The circularly polarized radiation is input into a hollow-core fiber for transport to a point of use. The transported radiation is converted back to plane-polarized radiation by another quarter-wave plate between the fiber and the point of use.
G02B 6/024 - Optical fibres with cladding with polarisation-maintaining properties
G02B 6/27 - Optical coupling means with polarisation selective and adjusting means
A61B 18/22 - Surgical instruments, devices or methods for transferring non-mechanical forms of energy to or from the body by applying electromagnetic radiation, e.g. microwaves using laser the beam being directed along or through a flexible conduit, e.g. an optical fibreHand-pieces therefor
49.
Uniformity adjustment method for a diode-laser line-projector
In a line projector a diode-laser beam having an elliptical cross-section is projected onto a Powell lens which spreads the beam to form a line of light. Distribution of power along the line of light is adjusted by rotating the diode-laser beam with respect to the Powell lens.
A carbon dioxide waveguide-laser includes an elongated resonator unit and an elongated power-supply unit. The resonator and power-supply units are spaced by a cooling unit including a plurality of longitudinally extending, spaced-apart fins, with fans arranged to drive air through the spaces between the fins.
A source of femtosecond pulses at center wavelengths of about 940 nm and about 1140 nanometers (nm) includes a mode-locked fiber MOPA delivering pulses having a center wavelength of about 1040 nm. The 1040-nanometer pulses are spectrally spread into a continuum spectrum extending in range between about 900 nm and about 1200 nm and having well defined side-lobes around the 940-nm and 1140-wavelengths. Radiation is spatially selected from these side-lobes and delivered as the 940-nm and 1140-nm pulses.
A carbon dioxide waveguide-laser includes an elongated resonator compartment and an elongated power supply compartment. The resonator and power-supply compartments are separated by a water-cooled heat sink.
Optical apparatus for amplifying pulses in a pulsed laser-beam includes a pulse-stretcher having a single transmission-grating in a multi-pass configuration at a non-normal incidence angle. A regenerative amplifier amplifies stretched pulses in the laser-beam. A pulse-compressor including two spaced-apart reflection-gratings in a multi-pass configuration compresses the amplified pulses. Pulse-parameters of the compressed amplified pulses are optimized by iteratively adjusting the incidence angle of the pulsed laser-beam on the transmission-grating of the pulse-stretcher and the spacing between the reflection-gratings of the pulse-compressor.
An architecture for current driver circuitry for diode laser systems is contemplated whereby the circuitry is both modular and minimally complex with respect to the number of components and connections.
H02M 3/156 - Conversion of DC power input into DC power output without intermediate conversion into AC by static converters using discharge tubes with control electrode or semiconductor devices with control electrode using devices of a triode or transistor type requiring continuous application of a control signal using semiconductor devices only with automatic control of output voltage or current, e.g. switching regulators
H05B 33/08 - Circuit arrangements for operating electroluminescent light sources
H01S 5/068 - Stabilisation of laser output parameters
55.
Tunable femtosecond laser-pulse source including a super-continuum generator
A mode-locked fiber MOPA delivers pulses of laser-radiation. A super-continuum generator including a bulk spectral-broadening element and a negative group-delay dispersion (NGDD) device is arranged to receive a pulse from the MOPA and cause the pulse to make a predetermined number of sequential interactions with the broadening element and the NGDD device. After making the predetermined interactions, the pulse is delivered from the super-continuum generator with a very broad spectral-bandwidth and a very short duration.
2 gas-discharge slab-laser comprising an unstable resonator constrained by a waveguide formed by planar discharge-electrodes, parasitic side-lobes appear on either side of a delivered main mode in a direction perpendicular to the electrode plane. A rotationally adjustable aperture is provided for transmitting the main mode and blocking the parasitic side-lobes.
A laser beam combining and power scaling device and method. A first highly reflective mirror residing perpendicular to the first optical axis reflecting radiation emitted from the first laser head. A first Q-switch in alignment with the first optical axis interposed between the first highly reflective mirror and the first laser head. A second highly reflective mirror residing perpendicular to the second optical axis reflecting radiation emitted from the second laser head. The second Q-switch in alignment with the second optical axis is interposed between the second highly reflective mirror and the first laser head. A third optical axis is coincident with the first optical axis. A third highly reflective mirror residing perpendicular to the third optical axis in alignment therewith. The third optical axis may include a third diode pumped laser head and Q-switch. A beam splitter resides at the intersection of the axes.
H01S 3/0941 - Processes or apparatus for excitation, e.g. pumping using optical pumping by coherent light of a semiconductor laser, e.g. of a laser diode
Apparatus for drilling a via-hole in a printed circuit board (PCB) includes a carbon monoxide laser deliver laser radiation pulses. The pulses have a relatively broad wavelength-range, and slow rising and falling edges. The rising and falling edges of the pulses are clipped using and acousto-optic modulator. A dispersion-compensator compensates for dispersion in the clipped pulses introduced by the AOM. Achromatic focusing optics focus the dispersion-compensated, clipped pulses on the PCB for the via-hole drilling.
An optical apparatus for delivering to a flow-cell of a flow-cytometer a plurality of beams of laser radiation each thereof having a different wavelength. The apparatus includes a dispersion compensation-prism and a plurality of directing-prisms equal in number to the number of laser-beam. The directing-prisms are arranged to direct the laser radiation beams directly therethrough into the dispersion compensation-prism as converging fan of beams in a first plane. The beams are transmitted by the compensation-prism as a converging fan of beams intersecting then proceeding as a diverging fan of beams in the first plane. A spherical focusing lens is arranged cooperative with a cylindrical lens for focusing the plurality of laser-beams as a plurality of spaced apart elongated focal spots in a plane in which the cytometer flow-cell is located.
G02B 27/12 - Beam splitting or combining systems operating by refraction only
G02B 6/28 - Optical coupling means having data bus means, i.e. plural waveguides interconnected and providing an inherently bidirectional system by mixing and splitting signals
60.
Traveling-wave ring-oscillators without a faraday rotator
A ring laser-resonator generating plane-polarized fundamental-frequency radiation includes an optically nonlinear crystal configured for type-II second-harmonic generation of fundamental-frequency radiation. The resonator is configured such that fundamental-frequency radiation circulating either clockwise or counter-clockwise therein makes two passes through the optically nonlinear crystal per round-trip in the resonator in opposite directions, with polarization planes perpendicular to each other. This arrangement forces unidirectional circulation of radiation in the resonator during which second-harmonic radiation is not generated by the crystal.
H01S 3/10 - Controlling the intensity, frequency, phase, polarisation or direction of the emitted radiation, e.g. switching, gating, modulating or demodulating
H01S 3/109 - Frequency multiplication, e.g. harmonic generation
In one embodiment, an apparatus may include an optical fiber that may have a surface non-normal to a longitudinal axis of a distal end portion of the optical fiber. The surface may define a portion of an interface configured to redirect electromagnetic radiation propagated from within the optical fiber and incident on the interface to a direction offset from the longitudinal axis. The apparatus may also include a doped silica cap that may be fused to the optical fiber such that the surface of the optical fiber may be disposed within a cavity defined by the doped silica cap.
A61B 18/22 - Surgical instruments, devices or methods for transferring non-mechanical forms of energy to or from the body by applying electromagnetic radiation, e.g. microwaves using laser the beam being directed along or through a flexible conduit, e.g. an optical fibreHand-pieces therefor
G02B 6/32 - Optical coupling means having lens focusing means
A method is disclosed for scribing a contained crack or vent in a chemically strengthened glass sheet. The glass has shallow surface regions under compressive stress, bounding a central region under tensile stress. The vent is formed by rapidly bulk-heating the glass, using radiation from a carbon monoxide laser, to a depth just below a surface compressive region and extending marginally into the tensile stress region then rapidly cooling the heated region with a water mist spray. The glass sheet can be subsequently divided along the vent by application of mechanical or thermal stress.
C03B 33/09 - Severing cooled glass by thermal shock
B23K 26/142 - Working by laser beam, e.g. welding, cutting or boring using a fluid stream, e.g. a jet of gas, in conjunction with the laser beamNozzles therefor for the removal of by-products
C03B 33/04 - Cutting or splitting in curves, especially for making spectacle lenses
B23K 26/12 - Working by laser beam, e.g. welding, cutting or boring in a special environment or atmosphere, e.g. in an enclosure
B23K 26/14 - Working by laser beam, e.g. welding, cutting or boring using a fluid stream, e.g. a jet of gas, in conjunction with the laser beamNozzles therefor
63.
Beam-combiner for fiber-delivered laser-beams of different wavelengths
A beam combiner for combining laser-beams of different colors along a common path includes a directing-prism for each of the laser-beams and one combining-prism. The directing-prisms are arranged to transmit the laser-beams to the combining-prism. The directing-prisms and the combining-prism are configured and arranged with respect to each other such that the directing-prism transmits the beams along the common path.
G02B 6/293 - Optical coupling means having data bus means, i.e. plural waveguides interconnected and providing an inherently bidirectional system by mixing and splitting signals with wavelength selective means
A laser label printer for use with a laser markable medium includes a laser-diode fiber-coupled to an optical train, which includes a focusing lens for focusing the radiation on the medium. The focusing lens is traversed across the medium, with incremental motion of the medium between traverses, for line by line printing of the label. The printer includes a feature for protecting the focusing lens from contamination, and self-diagnostic and adjustment features.
B41J 15/14 - Supporting, feeding, or guiding devicesMountings for web rolls or spindles characterised by being applied to printers having transversely-moving carriages and detached from the carriage
B41J 2/44 - Typewriters or selective printing mechanisms characterised by the printing or marking process for which they are designed characterised by selective application of radiation to a printing material or impression-transfer material using single radiation source, e.g. lighting beams or shutter arrangements
A laser includes an optically pumped semiconductor OPS gain-structure. The apparatus has a laser-resonator which includes a mode-locking device for causing the laser to deliver mode-locked pulses. The resonator has a total length selected such that the mode-locked pulses are delivered at a pulse repetition frequency less than 150 MHz. An optical arrangement within the resonator provides that radiation circulating in the resonator makes a plurality of incidences on the OPS gain-structure with a time less than the excited-state lifetime of the gain-structure between successive incidences.
H01S 5/183 - Surface-emitting [SE] lasers, e.g. having both horizontal and vertical cavities having only vertical cavities, e.g. vertical cavity surface-emitting lasers [VCSEL]
H01S 5/04 - Processes or apparatus for excitation, e.g. pumping
H01S 3/11 - Mode lockingQ-switchingOther giant-pulse techniques, e.g. cavity dumping
H01S 3/13 - Stabilisation of laser output parameters, e.g. frequency or amplitude
66.
Shaping of brittle materials with controlled surface and bulk properties
Methods of and devices for forming edge chamfers and through holes and slots on a material that is machined using a laser, such as an ultrafast laser. The shaped material has predetermined and highly controllable geometric shape and/or surface morphology. Further, a method of and a device for preventing re-deposition of the particles on a material that is machined using a laser, such as an ultrafast laser. A fluid is used to wash off the particles generated during the laser machining process. The fluid can be in a non-neutral condition, with one or more chemical salts added, or a condition allowing the coagulation of the particles in the fluid, such that the particles can be precipitated to avoid the reattachment to the machined substrate.
An optical amplifier for use as a final amplification stage for a fiber-MOPA has a gain-element including a thin wafer or chip of ytterbium-doped YAG. An elongated gain-region is formed in gain-element by multiple incidences of radiation from a diode-laser bar.
H01S 3/0941 - Processes or apparatus for excitation, e.g. pumping using optical pumping by coherent light of a semiconductor laser, e.g. of a laser diode
A mode-locked fiber laser has a resonator including a gain-fiber, a mode-locking element, and a spectrally-selective dispersion compensating device. The resonator can be a standing-wave resonator or a traveling-wave resonator. The dispersion compensating device includes only one diffraction grating combined with a lens and a mirror to provide a spatial spectral spread. The numerical aperture of the gain-fiber selects which portion of the spectral spread can oscillate in the resonator.
H01S 3/1055 - Controlling the intensity, frequency, phase, polarisation or direction of the emitted radiation, e.g. switching, gating, modulating or demodulating by controlling the mutual position or the reflecting properties of the reflectors of the cavity one of the reflectors being constituted by a diffraction grating
H01S 3/11 - Mode lockingQ-switchingOther giant-pulse techniques, e.g. cavity dumping
H01S 3/08 - Construction or shape of optical resonators or components thereof
H01S 3/117 - Q-switching using intracavity acousto-optic devices
A water-cooled heat-sink for a diode-laser bar includes a copper-cooling-unit having an integral mount thereon for the diode-laser bar. The copper-cooling-unit is attached to a steel base-unit. The base-unit and the cooling-unit are cooperatively configured such that at least one cooling-channel is formed in the cooling-unit by the attachment of the base-unit to the cooling-unit. The cooling-channel is positioned to cool the mount when cooling-water flows through the cooling-channel.
A diode-laser bar is mounted on water-cooled heat-sink between two ceramic sub-mounts for electrically isolating cooling-water in the heat-sink from the diode-laser bar. Mounting between the two ceramic sub-mounts also provides for balancing stresses due to differences in coefficient of thermal expansion (CTE) between the sub-mounts and the diode-laser bar. Both sub-mounts are in thermal communication with the heat-sink for providing two-sided cooling of the diode-laser bar.
A laser-radiation sensor includes a copper substrate on which is grown an oriented polycrystalline buffer layer surmounted by an oriented polycrystalline sensor-element of an anisotropic transverse thermoelectric material. An absorber layer, thermally connected to the sensor-element, is heated by laser-radiation to be measured and communicates the heat to the sensor-element, causing a thermal gradient across the sensor-element. Spaced-apart electrodes in electrical contact with the sensor-element sense a voltage corresponding to the thermal gradient as a measure of the incident laser-radiation power.
G01J 5/00 - Radiation pyrometry, e.g. infrared or optical thermometry
H01L 31/0368 - SEMICONDUCTOR DEVICES NOT COVERED BY CLASS - Details thereof characterised by their semiconductor bodies characterised by their crystalline structure or particular orientation of the crystalline planes including polycrystalline semiconductors
G01J 5/12 - Radiation pyrometry, e.g. infrared or optical thermometry using electric radiation detectors using thermoelectric elements, e.g. thermocouples
A laser-radiation sensor includes a copper substrate on which is grown an oriented polycrystalline buffer layer surmounted by an oriented polycrystalline sensor-element of an anisotropic transverse thermoelectric material. An absorber layer, thermally connected to the sensor-element, is heated by laser-radiation to be measured and communicates the heat to the sensor-element, causing a thermal gradient across the sensor-element. Spaced-apart electrodes in electrical contact with the sensor-element sense a voltage corresponding to the thermal gradient as a measure of the incident laser-radiation power. At least two protection layers are positioned between the sensor layer and the absorber layer.
G01J 5/00 - Radiation pyrometry, e.g. infrared or optical thermometry
H01L 31/0368 - SEMICONDUCTOR DEVICES NOT COVERED BY CLASS - Details thereof characterised by their semiconductor bodies characterised by their crystalline structure or particular orientation of the crystalline planes including polycrystalline semiconductors
G01J 5/12 - Radiation pyrometry, e.g. infrared or optical thermometry using electric radiation detectors using thermoelectric elements, e.g. thermocouples
In a line projector a diode-laser beam having an elliptical cross-section is projected onto a Powell lens which spreads the beam to form a line of light. Distribution of power along the line of light is adjusted by rotating the diode-laser beam with respect to the Powell lens.
A hybrid CW MOPA includes an OPS-laser resonator delivering radiation in a plurality of longitudinal lasing-modes or wavelengths. The multiple longitudinal mode output is amplified in a fiber-amplifier. Amplified lasing-modes from the fiber-amplifier are frequency-converted by an optically nonlinear crystal in a ring-resonator having the same length as the laser resonator, such that the ring-resonator is resonant for all of the amplified lasing-modes.
H01S 3/082 - Construction or shape of optical resonators or components thereof comprising three or more reflectors defining a plurality of resonators, e.g. for mode selection or suppression
2 laser has a Z-shaped folded waveguide formed by three ceramic tubes. Ends of the adjacent tubes are shaped and fitted together to form a common aperture. The tubes are held fitted together by spaced-apart parallel discharge electrodes. Four minors are arranged to form a laser-resonator having a longitudinal axis extending through the tubes.
H01S 3/03 - Constructional details of gas laser discharge tubes
H01S 3/223 - Gases the active gas being polyatomic, i.e. containing two or more atoms
H01S 3/036 - Means for obtaining or maintaining the desired gas pressure within the tube, e.g. by gettering or replenishingMeans for circulating the gas, e.g. for equalising the pressure within the tube
H01S 3/038 - Electrodes, e.g. special shape, configuration or composition
H01S 3/081 - Construction or shape of optical resonators or components thereof comprising three or more reflectors
H01S 3/0975 - Processes or apparatus for excitation, e.g. pumping by gas discharge of a gas laser using inductive or capacitive excitation
A two-chip OPS laser includes first and second OPS-chips each emitting the same fundamental wavelength in first and second resonators. The first and second resonators are interferometrically combined on a common path terminated by a common end-mirror. The interferometric combination provides for automatic wavelength-locking of the laser, which can eliminate the need for a separate wavelength selective device in the laser.
H01S 3/10 - Controlling the intensity, frequency, phase, polarisation or direction of the emitted radiation, e.g. switching, gating, modulating or demodulating
77.
Optical parametric oscillator pumped by femtosecond thin-disk laser
Pulses from a mode-locked Yb-doped laser (12) are spectrally broadened in an optical fiber (28), and temporally compressed in a grating compressor (32), then frequency-doubled (34) and used to pump an optical parametric oscillator (OPO) (40). The OPO output is tunable over a wavelength range from about 600 nm to about 1100 nm. Mode-locking in the Yb-doped laser (12) is accomplished with a SESAM (14) or by Kerr-lens mode-locking with a Kerr medium (82) and a hard aperture (84).
G02F 1/39 - Non-linear optics for parametric generation or amplification of light, infrared, or ultraviolet waves
H01S 3/10 - Controlling the intensity, frequency, phase, polarisation or direction of the emitted radiation, e.g. switching, gating, modulating or demodulating
A diode laser assembly including a plurality of diode bars disposed on a generally flat base plate and being oriented to emit a plurality of laser beams in a first direction. A reflector is spaced in the first direction from each of the diode bars in the first. Each reflector has at least two reflecting surfaces, one for reflecting the laser beams into a second direction different from the first direction and the other for reflecting the laser beams into a third direction different from the first and second directions to produce a spatially combined laser beam. Each reflector is moveable relative to one another and to the diode bars for adjusting the individual laser beams within the spatially-combined laser beam for optimizing the quality of the spatially combined laser beam.
A laser beam combining and power scaling device and method. A first highly reflective mirror residing perpendicular to the first optical axis reflecting radiation emitted from the first laser head. A first Q-switch in alignment with the first optical axis interposed between the first highly reflective mirror and the first laser head. A second highly reflective mirror residing perpendicular to the second optical axis reflecting radiation emitted from the second laser head. The second Q-switch in alignment with the second optical axis is interposed between the second highly reflective mirror and the first laser head. A third optical axis is coincident with the first optical axis. A third highly reflective mirror residing perpendicular to the third optical axis in alignment therewith. The third optical axis may include a third diode pumped laser head and Q-switch. A beam splitter resides at the intersection of the axes.
H01S 3/082 - Construction or shape of optical resonators or components thereof comprising three or more reflectors defining a plurality of resonators, e.g. for mode selection or suppression
H01S 3/11 - Mode lockingQ-switchingOther giant-pulse techniques, e.g. cavity dumping
2 gas-discharge laser, each laser output pulse is generated by train or burst of shorter RF pulses. When the time between laser output pulses becomes short enough that the power in one pulse would be reduced by gas-discharge heating effects of a previous pulse, power in the RF pulse trains is varied by varying the duration or duty cycle of pulses in the bursts, thereby keeping output-pulse power in the laser output pulses constant. RF pulses in any burst can have a different duration for tailoring the temporal shape of a corresponding laser-output pulse.
H01S 3/10 - Controlling the intensity, frequency, phase, polarisation or direction of the emitted radiation, e.g. switching, gating, modulating or demodulating
2 slab-laser is contained in a fluid cooled housing having three compartments. One compartment houses discharge electrodes and a laser resonator. Another compartment houses a radio-frequency power supply (RFPS) assembled on a fluid-cooled chill plate and an impedance-matching network. The remaining compartment houses beam-conditioning optics including a spatial filter. The housing and RFPS chill-plate are on a common coolant-fluid circuit having a single input and a single output. The spatial filter is optionally fluid-coolable on the common coolant fluid circuit.
An optically pumped semiconductor laser is assembled in an enclosure comprising a base, a first mounting frame attached to the base, a second mounting frame attached to the first mounting frame and a cover attached to the second mounting frame. The assembly base, frames, and cover forms an undivided enclosure, with the frames contributing to walls of the enclosure. Components of the laser are assembled sequentially on the base and the frames. The frames are irregular in height to permit flexibility in the mounting-height of components. This reduces the extent to which compactness of the enclosure is limited by any one component.
2 gas-discharge laser is energized by the output a radio-frequency power supply (RFPS). Output-power of the laser is stabilized by adjustments of the RFPS responsive to periodic measurements of the laser output-power using detector output amplified by an amplifier. The amplifier has an offset-voltage which is subject to drift. A synchronous auto-zero arrangement is provided for canceling out the offset-voltage of the amplifier immediately prior to each periodic measurement of the laser output power.
A mounting fixture for mounting an optical element on a base-plate has spaced-apart parallel legs attachable by brackets to the base-plate and a mounting platform attached to the legs. The platform can be heated by a removable heater. The optical element is held in a mounting tab attached to the platform by a solder-pad. Heating the platform softens the solder-pad allowing the tab and the element to be aligned. Removing the heat allows the pad to harden to complete the attachment and retain the alignment of the element on the mount.
A diode-laser bar package includes a diamond composite heat-sink on which is soft-solder bonded a copper-pad having an area much greater than that of the diode-laser bar. A constraining-block of a metal having a CTE matching that of the diode-laser bar is hard-solder bonded to the conductive pad. The constraining-block is configured such that the conductive pad in the region of the diode-laser bar has a CTE about equal to that of the constraining-block, and, accordingly, the diode-laser bar.
A laser and amplifier combination delivers a sequence of optical pulses at a predetermined pulse-repetition frequency PRF. An interferometer generates a signal representative of the carrier-envelope phase (CEP) of the pulses at intervals corresponding to the PRF. The signal includes frequency components from DC to the PRF. The signal is divided into high and low frequency ranges. The high and low frequency ranges are sent to independent high frequency and low frequency control electronics, which drive respectively a high-frequency CEP controller and a low frequency controller for stabilizing the CEP of pulses in the sequence.
2 gas-discharge laser includes a plurality of power-oscillators phase-locked to a common reference oscillator. Outputs of the phase-locked power-oscillators are combined by a power combiner for delivery, via an impedance matching network, to discharge-electrodes of the laser. In one example the powers are analog power-oscillators. In another example, the power-oscillators are digital power-oscillators.
A diode-laser bar stack includes a plurality of diode-laser bars having different temperature dependent peak-emission wavelengths. The stack is arranged such that the bars can be separately powered. This allows one or more of the bars to be “on” while others are “off”. A switching arrangement is described for selectively turning bars on or off, responsive to a signal representative of the temperature of the diode-laser bar stack, for providing a desired total emission spectrum.
A beam combiner for combining laser-beams of different colors along a common path includes a directing-prism for each of the laser-beams and one combining-prism. The directing-prisms are arranged to transmit the laser-beams to the combining-prism. The directing-prisms and the combining-prism are configured and arranged with respect to each other such that the directing-prism transmits the beams along the common path.
Systems and methods for material singulation. According to some embodiments, methods for material singulation may include applying a first laser output to the material, the first laser output causing a modification of a material property of the material when exposed to the first laser output; and applying a second laser output to the material that was exposed to the first laser output to cause singulation of the material in such a way that surfaces created by the singulation of the material are substantially free from defects.
B23K 26/00 - Working by laser beam, e.g. welding, cutting or boring
B23K 26/14 - Working by laser beam, e.g. welding, cutting or boring using a fluid stream, e.g. a jet of gas, in conjunction with the laser beamNozzles therefor
B23K 26/16 - Removal of by-products, e.g. particles or vapours produced during treatment of a workpiece
B23K 26/38 - Removing material by boring or cutting
B23K 26/359 - Working by laser beam, e.g. welding, cutting or boring for surface treatment by providing a line or line pattern, e.g. a dotted break initiation line
C03B 33/02 - Cutting or splitting sheet glassApparatus or machines therefor
B23K 26/364 - Laser etching for making a groove or trench, e.g. for scribing a break initiation groove
B23K 26/40 - Removing material taking account of the properties of the material involved
A laser and amplifier combination delivers a sequence of optical pulses at a predetermined pulse-repetition frequency PRF. An interferometer generates a signal representative of the carrier-envelope phase (CEP) of the pulses at intervals corresponding to the PRF. The signal includes frequency components from DC to the PRF. The signal is divided into high and low frequency ranges. The high and low frequency ranges are sent to independent high frequency and low frequency control electronics, which drive respectively a high-frequency CEP controller and a low frequency controller for stabilizing the CEP of pulses in the sequence.
H01S 3/10 - Controlling the intensity, frequency, phase, polarisation or direction of the emitted radiation, e.g. switching, gating, modulating or demodulating
A laser includes an optically pumped semiconductor OPS gain-structure. The apparatus has a laser-resonator which includes a mode-locking device for causing the laser to deliver mode-locked pulses. The resonator has a total length selected such that the mode-locked pulses are delivered at a pulse repetition frequency of about 100 MHz. An optical arrangement within the resonator provides that radiation circulating in the resonator makes a plurality of incidences on the OPS gain-structure with a time less than the excited-state lifetime of the gain-structure between successive incidences.
A fiber-MOPA includes a seed-pulse source followed by fiber amplifier stages. The seed pulse source delivers signal pulses for performing a laser operation and delivers radiation between the seed pulses to maintain the collective average of the seed pulse power and intermediate radiation power constant. Keeping this average power constant keeps the instantaneous available gain of the fiber amplifier stages constant. This provides that the seed pulse delivery can be changed from one regime to a next without a period of instability between the regimes.
H04B 10/17 - in which processing or amplification is carried out without conversion of the signal from optical form
H01S 3/10 - Controlling the intensity, frequency, phase, polarisation or direction of the emitted radiation, e.g. switching, gating, modulating or demodulating
2 gas discharge laser energized by a radio frequency (RF) power source a transformer having selectively variable output impedance is used to match output impedance of the power source to the impedance of discharge electrodes of the laser. A similar transformer can be used to impose a selective variable phase-shift on the RF power from the source. The variable impedance transformer can also be used for impedance matching between amplifier stages in the power source.
Systems and methods are disclosed for shutting down a laser system in an intelligent and flexible manner. An intelligent laser interlock system includes both hardwired components, and intelligent components configured to execute computing instructions. The hardwired components and the intelligent components are configured to shutdown the laser system to one or more alternative shutdown states in response to one or more interlock signals.
F16P 3/20 - Control arrangements requiring the use of both hands for electric control systems
H01S 3/23 - Arrangement of two or more lasers not provided for in groups , e.g. tandem arrangement of separate active media
H01S 3/00 - Lasers, i.e. devices using stimulated emission of electromagnetic radiation in the infrared, visible or ultraviolet wave range
H01S 3/10 - Controlling the intensity, frequency, phase, polarisation or direction of the emitted radiation, e.g. switching, gating, modulating or demodulating
H01S 3/091 - Processes or apparatus for excitation, e.g. pumping using optical pumping
2 laser has a Z-shaped folded waveguide formed by three ceramic tubes. Ends of the adjacent tubes are shaped and fitted together to form a common aperture. The tubes are held fitted together by spaced-apart parallel discharge electrodes. Four mirrors are arranged to form a laser-resonator having a longitudinal axis extending through the tubes.
A gain-module for use in an OPS-laser includes a multilayer semiconductor gain-structure surmounting a multilayer compound mirror-structure. Within the multilayer compound mirror-structure is a relatively thick layer of diamond which serves as a heat-spreader.
H01S 5/183 - Surface-emitting [SE] lasers, e.g. having both horizontal and vertical cavities having only vertical cavities, e.g. vertical cavity surface-emitting lasers [VCSEL]
98.
Unit-magnification catadioptric and catoptric projection optical systems
Ring-field, catoptric and catadioptric, unit-magnification, projection optical systems having non-concentric optical surfaces are disclosed. Each system has a system axis with object and image planes on opposite sides of the system axis. The non-concentric surfaces allow for working distances of the object and image planes in excess of 100 millimeters to be achieved, with a ring-field width sufficient to allow a rectangular object-field having a long dimension in excess of 100 mm to be projected.
G02B 17/00 - Systems with reflecting surfaces, with or without refracting elements
G02B 9/08 - Optical objectives characterised both by the number of the components and their arrangements according to their sign, i.e. + or – having two components only two + components arranged about a stop
99.
Diode-laser illuminator with interchangeable modules for changing irradiance and beam dimensions
Projection apparatus for projecting a radiation spot on a working plane includes a plurality of stacks of diode-laser bars. Each stack provides a beam of laser radiation. The diode-laser bars in each stack are arranged one above another in the fast-axis direction of the diode-laser bars. A corresponding plurality of beam-expanders expands the beam from the corresponding diode-laser bar stack in the slow-axis direction of the diode laser bars only. A focusing lens collects the slow-axis expanded beams and projects the slow-axis expanded beams into the working plane to form the radiation spot.
An OPS-chip is soldered mirror-structure-side down on an upper surface of diamond-heat spreader. A metal frame is also soldered to the upper surface of the heat-spreader. The lower surface of the diamond heat-spreader is either soldered to, or clamped against, a surface of a heat-sink. The dimensions of the frame and the heat spreader are selected such that at a solidification temperature of the solder at the center of the upper surface of the heat-spreader has an effective CTE comparable with that of the OPS-chip. The lower surface of the heat-spreader can be soldered to the heat sink surface or clamped against the heat-sink surface by the frame.
patents
