Coherent Patent Grants

Power scalable optical systems for generating, transporting, and delivering high power, high quality laser beams

Granted: March 20, 2007
Patent Number: 7193771
Power scalable, rectangular, multi-mode, self-imaging, waveguide technologies are used with various combination of large aperture configurations, 20, 50, 80, 322, 324, 326, 328, 330, 332, 334, 336, 338, Gaussian 360 and super-Gaussian 350 beam profiles, thermal management configurations 100, flared 240 and tapered 161 waveguide shapes, axial or zig-zag light propagation paths, diffractive wall couplers 304, 306, 308, 310, 312, 314, 316, 318, 320 and phase controller 200, flexibility 210,…

Optical pulse duration extender

Granted: February 27, 2007
Patent Number: 7184216
An optical pulse extender includes a delay loop formed by a plurality of mirrors and a graded reflectivity beamsplitter. The mirrors and the beamsplitter are configured and aligned such that a pulse to be broadened makes a predetermined number of round trips in the delay loop and is incident on a different zone of the beamsplitter after each round trip. The different zones of the beamsplitter have different reflection values and different transmission values. These values are selected…

High-power external-cavity optically-pumped semiconductor lasers

Granted: February 20, 2007
Patent Number: 7180928
External-cavity optically-pumped semiconductor lasers (OPS-lasers) including an OPS-structure having a mirror-structure surmounted by a surface-emitting, semiconductor multilayer (periodic) gain-structure are disclosed. The gain-structure is pumped by light from diode-lasers. The OPS-lasers can provide fundamental laser output-power of about two Watts (2.0 W) or greater. Intracavity frequency-converted arrangements of the OPS-lasers can provide harmonic laser output-power of about…

Detection system for optical beam pointing and shaping

Granted: January 16, 2007
Patent Number: 7164108
Apparatus for circularizing an optical beam and directing the beam into an optical system has mutually perpendicular X, Y, and Z axes. The Z-axis is the propagation axis of the beam. A detector arrangement receives a sample of the optical beam. The detector arrangement has four detector elements arranged in four quadrants defined by an x-axis and a y-axis of the detector arrangement, perpendicular to each other. The x and y-axes of the quadrant detector are arranged at 45 degrees to the…

Fiber amplifier with suppression of amplified spontaneous emission

Granted: November 21, 2006
Patent Number: 7139119
A fiber amplifier module for amplifying a signal pulse includes an optically pumped double-pass fiber amplifier in which a fiber Bragg grating reflects an amplified pulse in between the first and second amplification passes, and transmits most forward-propagating amplified spontaneous emission (ASE) generated by the optical pumping. The reflected amplified pulse from the double-pass amplifier, and reverse-propagating ASE generated by the optical pumping are reflected from another fiber…

Wide-stripe single-mode diode-laser

Granted: November 21, 2006
Patent Number: 7139300
A wide-stripe diode-laser includes a lower cladding region, a lower waveguide region, an active region, an upper waveguide region, and an upper cladding region all comprising semiconductor layers epitaxially grown on a semiconductor substrate. An elongated rectangular electrode on the upper cladding layer defines a stripe or pumped section. Adjacent the electrode is an unpumped section in which at least the quantum-well layer has been treated to cause the active region to be disordered.…

InGaN diode-laser pumped II-VI semiconductor lasers

Granted: November 14, 2006
Patent Number: 7136408
A semiconductor laser includes a multilayer semiconductor laser heterostructure including at least one active layer of a II-VI semiconductor material and is optically pumped by one or more indium gallium nitride (InGaN) diode-lasers. Group II elements in the II-VI semiconductor material are zinc, cadmium, magnesium, beryllium, strontium, and barium. Group VI elements in the II-VI semiconductor material are Sulfur, Selenium, and Tellurium. In one example of the laser an edge emitting…

Intracavity frequency-tripled CW laser with traveling-wave ring-resonator

Granted: October 31, 2006
Patent Number: 7130321
A traveling-wave ring laser resonator includes one or more gain-elements for generating fundamental radiation and three optically nonlinear crystals. A portion of the fundamental radiation is converted to second-harmonic radiation in a first of the crystals. Remaining fundamental radiation and the second-harmonic radiation traverse a second of the optically nonlinear crystals where a portion of each is converted to third-harmonic radiation. Fundamental and second-harmonic radiation pass…

Pulsed COlaser including an optical damage resistant electro-optical switching arrangement

Granted: September 26, 2006
Patent Number: 7113529
An electro-optical switch includes an optical assembly arranged to transmit laser-radiation. The optical assembly comprises an active optical crystal. On one of two opposite surfaces of the crystal is an optical window formed from a material having a refractive index lower than the material of the crystal. Heat deposited, as a result of transmission of the laser-radiation, at the surface of the crystal in contact with the widow is transferred to the window, thereby reducing the potential…

Fiber amplifier with suppression of amplified spontaneous emission

Granted: September 12, 2006
Patent Number: 7106501
A fiber amplifier module for amplifying a signal pulse includes an optically pumped double-pass fiber amplifier in which a fiber Bragg grating reflects an amplified pulse in between the first and second amplification passes, and transmits most forward-propagating amplified spontaneous emission (ASE) generated by the optical pumping. The reflected amplified pulse from the double-pass amplifier, and reverse-propagating ASE generated by the optical pumping are reflected from another fiber…

Micromechanical device having braking mechanism

Granted: August 15, 2006
Patent Number: 7091647
The present invention provides a brakeable microapparatus comprising a substrate and a structure overlying the substrate and movable relative to the substrate. A frictional brake overlies the structure and is movable into frictional engagement with the structure for holding the structure relative to the substrate.

Method and apparatus for measuring amplified stimulated emission in the output of a master oscillator power amplifier system

Granted: August 8, 2006
Patent Number: 7088450
A method for measuring amplified spontaneous emission (ASE) content in a beam of laser radiation emitted by a laser master oscillator power-amplifier system comprises directing the beam of light into a two-beam interferometer having unequal beam path lengths. The two beams interfering in the interferometer have equal amplitude and form a pattern of interference fringes. The beam-path difference is arranged to be greater than the coherence length of the ASE so that the ASE content of the…

Laser power meter

Granted: July 18, 2006
Patent Number: 7077564
A laser power meter and associated method are disclosed. The laser power meter has an absorber that is placed in a path of a laser beam during a power measurement, a temperature sensor for measuring the temperature of the absorber, a differentiator for determining a rate of change of the temperature of the absorber, and a processor that computes an estimated power of the laser beam based on the temperature and its rate of change without considering power related loss effects and then…

Q-switched, cavity dumped laser systems for material processing

Granted: June 6, 2006
Patent Number: 7058093
This disclosure discusses techniques for obtaining wavelength selected simultaneously super pulsed Q-switched and cavity dumped laser pulses utilizing high optical damage threshold electro-optic modulators, maintaining a zero DC voltage bias on the CdTe electro-optic modulator (EOM) so as to minimize polarization variations depending on the location of the laser beam propagating through the CdSe EOM crystal, as well as the addition of one or more laser amplifiers in a compact package and…

Microassembly and method for using same

Granted: May 16, 2006
Patent Number: 7044653
The present invention provides a microassembly comprising a support structure, a body having a rounded portion in close proximity to the support structure and a microelement carried by the body. A fastener is provided to secure the rounded portion of the body to the support structure. The rounded portion of the body is translatable relative to the support structure and rotatable relative to the support structure about an axis before being secured to the support structure for permitting…

Optical fiber coupling arrangement

Granted: May 16, 2006
Patent Number: 7046432
Apparatus for optically pumping a clad amplifier fiber includes one or more transmission fibers arranged and configured to insert pump-light from a pump light source such as a diode-laser into the cladding of the amplifier fiber. The pump light propagates through the cladding and a portion of the pump light is absorbed in the doped core of the amplifier fiber. At least one of the transmission fibers is arranged to receive an unabsorbed portion of the propagated pump light from the…

COwaveguide laser with beryllium oxide waveguides

Granted: May 16, 2006
Patent Number: 7046709
A pulsed, Q-switched, waveguide CO2 laser includes a plurality of waveguide channels formed in a block of a beryllium oxide ceramic material and is operated at a wavelength between about 9.2 and 9.7 micrometers. The laser has an output power up to 55% greater than that of a similarly configured laser, operated at the same wavelength and pulse conditions, but wherein the waveguide channels are formed in a block of an alumina ceramic material.

Power scalable optical systems for generating, transporting, and delivering high power, high quality, laser beams

Granted: May 9, 2006
Patent Number: 7042631
Power scalable, rectangular, multi-mode, self-imaging, waveguide technologies are used with various combination of large aperture configurations, 20, 50, 80, 322, 324, 326, 328, 330, 332, 334, 336, 338, Gaussian 360 and super-Gaussian 350 beam profiles, thermal management configurations 100, flared 240 and tapered 161 waveguide shapes, axial or zig-zag light propagation paths, diffractive wall couplers 304, 306, 308, 310, 312, 314, 316, 318, 320 and phase controller 200, flexibility 210,…

Time correlation of ultrafast laser pulses

Granted: May 2, 2006
Patent Number: 7038781
Time-correlation methods for determining pulse characteristics from a modelocked ultrafast laser include a cross-correlation method and an auto-correlation method. In the cross-correlation method, pulses from the laser and pulses from another modelocked laser are incident on a two-photon detector that responds when the pulses overlap in time. The lasers are synchronized to the same frequency and the phase difference between pulses from the two lasers is varied to vary the temporal pulse…

Pulsed COlaser including an optical damage resistant electro-optical switching arrangement

Granted: May 2, 2006
Patent Number: 7039079
A laser includes a gain medium located in a laser resonator. The gain medium generates plane polarized radiation plane polarized in a first polarization orientation. An electro-optical switch is located in the resonator. When the switch is activated the polarization plane of the laser radiation is rotated to a second orientation after making a forward and a reverse pass through the optical switch. When the switch is deactivated, the polarization orientation of the forward and reverse…