Coherent Patent Applications

MICROELECTRONIC DEVICE TRANSFER WITH UV-TRANSMISSIVE ADHESIVE AND LASER LIFT-OFF

Granted: March 14, 2024
Application Number: 20240088323
A method for inter-substrate transfer of microelectronic devices includes applying a polymer coating to a top surface of a microelectronic device located on a first substrate, depositing an ultraviolet-transmissive adhesive on a second substrate, contacting the polymer-coated top surface of the microelectronic device to the adhesive to bond the microelectronic device to the second substrate, detaching the microelectronic device from the first substrate, and, while the bottom surface of…

PASSIVELY DOUBLE-PASSED CHIRPED-FIBER-BRAGG-GRATING

Granted: January 11, 2024
Application Number: 20240014624
A system 200 for altering laser pulse duration includes a chirped fiber Bragg grating (cFBG) 122, a Faraday rotator 230, a retroreflector 240, and a fiber-optic polarization combiner 210 coupled to the chirped fiber Bragg grating 122 via the Faraday rotator 230. The combiner 210 directs a laser pulse via the Faraday rotator 230 to a first reflection in the cFBG 122, then directs the laser pulse to the retroreflector 240, then directs the laser pulse via the Faraday rotator 230 to a…

PASSIVELY DOUBLE-PASSED CHIRPED-FIBER-BRAGG-GRATING

Granted: January 11, 2024
Application Number: 20240014624
A system 200 for altering laser pulse duration includes a chirped fiber Bragg grating (cFBG) 122, a Faraday rotator 230, a retroreflector 240, and a fiber-optic polarization combiner 210 coupled to the chirped fiber Bragg grating 122 via the Faraday rotator 230. The combiner 210 directs a laser pulse via the Faraday rotator 230 to a first reflection in the cFBG 122, then directs the laser pulse to the retroreflector 240, then directs the laser pulse via the Faraday rotator 230 to a…

INTRACAVITY FREQUENCY CONVERSION IN SOLID-STATE LASER RESONATOR WITH END-PUMPING

Granted: October 26, 2023
Application Number: 20230344190
A method for intracavity frequency conversion includes end-pumping a solid-state gain medium in a laser resonator with a pump laser beam to generate an intracavity laser beam circulating in the laser resonator, and frequency-converting a portion of the intracavity laser beam in a nonlinear crystal, located in the laser resonator, to generate a frequency-converted laser beam. The method controls the output power and at least one output beam parameter of the frequency-converted laser beam…

TERMINATED HOLLOW-CORE FIBER WITH SUSPENDED FIBER-END

Granted: October 12, 2023
Application Number: 20230324613
A terminated hollow-core optical fiber includes an outer capillary having an end-face, a hollow-core optical fiber having a fiber-end located inside the outer capillary a non-zero distance away from the end-face of the outer capillary, a fiber jacket disposed on a surface of the hollow-core optical fiber, and an inner capillary disposed between the fiber jacket and an inner surface of the outer capillary. The inner capillary holds the hollow-core optical fiber via the fiber jacket such…

PULSE EQUALIZATION IN Q-SWITCHED GAS LASERS

Granted: May 18, 2023
Application Number: 20230155342
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…

CANTILEVER DEVICE FOR SHIFTING OPTICALLY NONLINEAR CRYSTAL

Granted: March 30, 2023
Application Number: 20230100424
A device for shifting a nonlinear crystal arranged to frequency convert a laser beam includes an anchor, a mount for holding the nonlinear crystal, and two parallel flexures each interconnecting the mount and the anchor to cantilever the mount from the anchor. Each flexure extends in a first horizontal direction from the mount to the anchor. The two flexures being offset from each other in a vertical direction. The device also includes a transducer connecting between the anchor and the…

ACTIVELY COOLED END-PUMPED SOLID-STATE LASER GAIN MEDIUM

Granted: January 26, 2023
Application Number: 20230029200
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…

ACTIVELY COOLED END-PUMPED SOLID-STATE LASER GAIN MEDIUM

Granted: January 26, 2023
Application Number: 20230029200
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…

THERMALLY ACTUATED ADAPTIVE OPTICS

Granted: December 29, 2022
Application Number: 20220413259
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…

METHOD AND APPARATUS FOR LASER ANNEALING

Granted: November 10, 2022
Application Number: 20220359197
A layer on a substrate is laser annealed by pulses in a plurality of laser beams formed into a uniform line beam. The laser beams are partitioned into a first set of beams and a second set of beams. The second set of beams is incident onto the layer from a smaller range of angles than all of the beams combined. Pulses in the beams are synchronized such that pulses in the first set of beams are incident on the layer before pulses in the second set of beams. Pulses in the first set of…

RESONANTLY ENHANCED FREQUENCY CONVERSION WITH ADAPTIVE THERMAL-LENSING COMPENSATION

Granted: October 20, 2022
Application Number: 20220337031
A system for resonantly enhanced frequency conversion includes a nonlinear crystal for frequency converting a pump laser beam, and mirrors forming a ring resonator for the pump laser beam such that a closed propagation path of the pump laser beam, inside the ring resonator, passes through the nonlinear crystal. The mirrors include an adaptive mirror, a curved-mirror pair positioned in a first segment of the propagation path spanning between the adaptive mirror and the nonlinear crystal,…

MULTIPASS LASER AMPLIFIER AND NO-OPTICAL-POWER BEAM STEERING ELEMENT

Granted: April 28, 2022
Application Number: 20220131337
A multipass laser amplifier includes a mirror, a mirror device, a gain crystal, and refractive or diffractive beam-steering element. The gain crystal is positioned on a longitudinal axis of the multipass laser amplifier between the mirror and the mirror device. The beam-steering element is positioned on the longitudinal axis between the gain crystal and the mirror device. The beam-steering element has no optical power and deflects a laser beam, by refraction or diffraction, for each of…

780 nm ULTRASHORT-PULSED FIBER LASER

Granted: March 17, 2022
Application Number: 20220085566
An erbium fiber laser produces a beam of ultrashort laser pulses having a center wavelength greater than 780 nanometers, an average power greater than 0.5 watt, and a spectral bandwidth compressible to a pulse duration of less than 200 femtoseconds. The laser includes a fiber preamplifier that is energized by a counter-propagating pump beam, has relatively low population inversion in a relatively long optical gain fiber, and provides a spectrally-shaped beam for further amplification.…

APPARATUS AND METHOD FOR GENERATING 780 nm ULTRASHORT-PULSED LASER RADIATION

Granted: March 17, 2022
Application Number: 20220085564
An erbium fiber laser produces a beam of ultrashort laser pulses having a center wavelength greater than 780 nanometers, an average power greater than 0.5 watt, and a pulse duration less than 200 femtoseconds. The fiber laser includes an erbium fiber amplifier that is energized by a pump beam having a pump wavelength longer than 1520 nanometers. The pump wavelength is selected to provide uniform gain over the broad spectral bandwidth of a seed beam and minimal gain at shorter wavelengths…

PULSED LASER WITH INTRACAVITY FREQUENCY CONVERSION AIDED BY EXTRA-CAVITY FREQUENCY CONVERSION

Granted: February 17, 2022
Application Number: 20220052504
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…

HIGH-RADIANCE WAVELENGTH-AGILE INCOHERENT LIGHT-SOURCE

Granted: January 27, 2022
Application Number: 20220026615
A source of high-radiance broad-band incoherent light includes an optical waveguide, having a core made of phosphor granules embedded in a matrix of glass and a cladding. The core having a relatively high refractive index and the cladding having a relatively low refractive index. The phosphor granules and the glass matrix having about the same refractive index. Radiation from one or more diode-lasers is injected into one end of the waveguide to energize the phosphor granules, producing…

HIGH DYNAMIC RANGE OPTICAL SENSING DEVICE EMPLOYING BROADBAND OPTICAL FILTERS INTEGRATED WITH LIGHT INTENSITY DETECTORS

Granted: January 20, 2022
Application Number: 20220021828
A high dynamic range image sensors enabled by integrating broadband optical filters with individual sensor pixels of a pixel array. The broadband optical filters are formed of engineered micro or nanostructures that exhibit large differences in transmittance, e.g. up to 5 to 7 orders of magnitude. Such high transmittance difference can be achieved by using a single layer of individually designed filters, which show varied transmittance as a result of the distinct absorption of various…

LASER WELDING METHOD

Granted: November 25, 2021
Application Number: 20210362271
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…

SECOND-HARMONIC GENERATION CRYSTAL

Granted: August 26, 2021
Application Number: 20210265802
An optic produces a beam of ultraviolet laser radiation from a beam of visible laser radiation and spatially separates the ultraviolet laser beam from the visible laser beam. The optic includes two crystals made of the same optically-nonlinear material that are contact bonded along a planar interface. One crystal has principle crystal axes that are oriented for type-I second-harmonic generation. The ultraviolet laser beam exits the optic through an uncoated surface of the other crystal.…