Coherent Patent Grants

Apparatus for projecting a line of light from a diode-laser array

Granted: September 4, 2007
Patent Number: 7265908
Optical apparatus for projecting a line of light includes a diode-laser bar having a plurality of individual emitters, input and output microlens arrays, a lens and other optical elements. The diode-laser bar, the microlens arrays, and the lens are configured and arranged such that the microlens arrays form three or more slow-axis intermediate near-field images of each emitter in a plane immediately adjacent the output microlens array, and in a telecentric arrangement with the lens. The…

Dielectric coupled COslab laser

Granted: August 28, 2007
Patent Number: 7263116
A slab laser includes two elongated electrodes arranged spaced apart and face-to-face. Either one or two slabs of a solid dielectric material extend along the length of the electrodes between the electrodes. A discharge gap is formed either between one of the electrodes and one dielectric slab, or between two dielectric slabs. The discharge gap is filled with lasing gas. A pair of mirrors is configured and arranged to define a laser resonator extending through the gap. An RF potential is…

Attenuator for high-power unpolarized laser beams

Granted: August 21, 2007
Patent Number: 7259914
A method for attenuating an unpolarized laser beam includes separating the laser beam into two plane-polarized beams. The plane-polarized beams are polarization rotated. Each of the polarization-rotated beams is separated into two plane-polarized portions. One of the portions of one polarization-rotated beam is combined with one of the portions of the other polarization-rotated beam to provide an attenuated output-beam.

Dielectric coupled COslab laser

Granted: August 21, 2007
Patent Number: 7260134
An slab CO2 laser includes spaced-apart elongated slab electrodes. A lasing gas fills a discharge gap between the electrodes. An RF power supply is connected across the electrodes and sustains an electrical discharge in the lasing gas in the discharge gap. Either one or two ceramic inserts occupy a portion of width of the electrodes and in contact with the electrodes. A discharge gap is formed between the portions of the width of the electrodes not occupied by the insert or inserts.…

Optically pumped semiconductor ring laser

Granted: August 7, 2007
Patent Number: 7254153
An optically pumped semiconductor laser includes an active ring-resonator having two or more optically pumped semiconductor (OPS) structures each including a mirror-structure and a multilayer gain-structure. The mirror-structures serve as fold mirrors for the resonator axis. An optically nonlinear crystal may be included in the ring-resonator for generating second-harmonic radiation from fundamental radiation generated in the resonator. Another optically nonlinear crystal may be provided…

Line-narrowed dye laser

Granted: August 7, 2007
Patent Number: 7254156
A dye-laser includes a resonator formed between two mirrors. The resonator has a longitudinal Z-axis and transverse X- and Y-axes perpendicular to each other and perpendicular to the Z-axis. A beam of laser radiation circulates in the laser resonator generally in a path along the Z-axis. An optical arrangement is provided for expanding the circulating beam in the Y-axis in one circulation direction and correspondingly compressing the expanded beam in the opposite circulation direction. A…

Wavelength locked fiber-coupled diode-laser bar

Granted: July 31, 2007
Patent Number: 7251259
In apparatus for wavelength stabilizing and spectrally narrowing an output beam of a diode-laser, a cylindrical lens is arranged to collimate the beam in the fast axis of the diode laser without reducing divergence in the slow axis of the diode-laser. A length of optical fiber is arranged to receive the fast-axis collimated beam from the lens. The optical fiber has a core surrounded by a first cladding, the first cladding being surrounded by a second cladding. The core of the optical…

Wavelength-locked fiber-coupled diode-laser bar

Granted: July 31, 2007
Patent Number: 7251260
In apparatus for wavelength stabilizing and spectrally narrowing an output beam of a diode-laser, a cylindrical lens is arranged to collimate the beam in the fast axis of the diode laser without reducing divergence in the slow axis of the diode-laser. An optical fiber is arranged to receive the fast-axis collimated beam from the lens. The optical fiber has a multimode core surrounded by a first cladding, the first cladding being surrounded by a second cladding. The core of the optical…

Laser illuminated projection displays

Granted: July 17, 2007
Patent Number: 7244028
A projection video display includes at least one laser for delivering a light beam. The display includes a beam homogenizer and a condenser lens. A scanning arrangement is provided for scanning the light in beam in a particular pattern over the condenser lens in a manner that effectively increases the beam divergence. The scanned beam is homogenized by a beam homogenizer and a spatial light modulator is arranged to receive the homogenized scanned light beam and spatially modulate the…

Stabilized frequency-converted laser system

Granted: July 10, 2007
Patent Number: 7242700
A laser system includes an optically pumped laser resonator that produces a fundamental-wavelength beam. A temperature-tuned frequency converter outside the laser resonator converts a portion of the fundamental-wavelength beam to a frequency-converted beam. The frequency converter includes at least one temperature-tuned optically nonlinear crystal. The power and position of the frequency-converted beam are dependent on the temperature of the optically nonlinear crystal and the optical…

Closed-loop purging system for laser

Granted: July 3, 2007
Patent Number: 7239656
A method of minimizing contamination of optical components of a laser resonator is disclosed. The resonator components are located in an enclosure, which may contain contaminants including water vapor and organic favor released by the optical components, mounts of the optical components, or the enclosure itself. The enclosure may also contain suspended particulate matter. In order to reduce the level of these contaminants, a purging system extracts gas from the enclosure and passes the…

Method and apparatus to coherently combine high-power beams in self-imaging waveguides

Granted: July 3, 2007
Patent Number: 7239777
An apparatus for combining laser beams into a single high power output beam. The apparatus includes a self-imaging waveguide (SIWG) with parallel reflective elements that have a length that is an integer multiple of the self-imaging or Talbot length of the waveguide or an integer fraction of this self-imaging length. The apparatus also includes a system for controlling the phase of each of laser beams provided to an inlet of the waveguide. The phases are controlled, e.g., with phase…

Tunable optical filter, optical apparatus for use therewith and method utilizing same

Granted: May 22, 2007
Patent Number: 7221452
An apparatus for filtering an input beam of light to produce an output beam of light is provided. The apparatus facilitates tuning an input beam of light to a desired wavelength by directing the input beam of light, via a mirror, onto a diffractive optical element and returning the diffracted portion of the input beam of light as an output beam of light. The apparatus may also include a polarization recovery element adapted for receiving the input beam of light and outputting a first and…

Wavelength stabilized diode-laser array

Granted: May 1, 2007
Patent Number: 7212553
A fiber laser including doped-core fiber having inner and outer cladding is optically pumped by plurality of diode-lasers. Light emitted by the diode-lasers is coupled into a single multimode optical fiber. Light from the multimode optical fiber is directed to a wavelength selective reflecting device that is partially reflective in a narrow reflection band about a peak reflection wavelength. A portion of the light having the peak reflection wavelength is reflected from the wavelength…

Off-peak optical pumping of yttrium orthovanadate

Granted: April 10, 2007
Patent Number: 7203214
A laser includes an Nd:YVO4 crystal end-pumped with diode-laser light having a wavelength at which the absorption coefficient for Nd:YVO4 is less than about 0.35 (35%) of the absorption coefficient at 808 nm.

Systems and methods for forming a laser beam having a flat top

Granted: April 3, 2007
Patent Number: 7199330
Multiple laser beams, each having a shape such as a Gaussian profile, can be incoherently combined to obtain a shaped, flat top laser beam. The combined laser beams can provide power levels necessary for material processing applications such as annealing, drilling, and cutting, while minimizing the amount of unused power. The lasers can be positioned in an array in order to shape the flat top beam, and can be staggered in position where necessary to give each output beam an equal beam…

Optical vibration imager

Granted: March 20, 2007
Patent Number: 7193720
A remote sensor capable of imaging vibrations at many simultaneous points using high-speed imaging cameras is disclosed. The preferred embodiment operates in heterodyne detection mode using a single camera to capture signals to recover multi-pixel vibrations. One alternative embodiment employs two cameras and homodyne optical I/Q detection. A second alternative embodiment uses a single camera and temporally phase shifted local oscillator to also carry out homodyne optical I/Q detection.…

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…