Abstract: A laser light source according to the present invention includes a laser element that outputs a fundamental wave; a wavelength conversion element into which the fundamental wave is input and that converts at least a part of the fundamental wave input therein to a converted wave having a wavelength shorter than the wavelength of the fundamental wave; a waveguide that attenuates a component of the fundamental wave included in an output wave from the wavelength conversion element; and a diffraction grating that is formed on the waveguide and feeds back the fundamental wave output from the wavelength conversion element to lock the wavelength or the frequency of the fundamental wave output from the laser element. The diffraction grating is formed at a position determined taking into account an amount by which the fundamental wave is attenuated in the waveguide.

Abstract: A laser processing apparatus including a laser oscillator, a laser processing machine, and a control part controlling the laser oscillator and the laser processing machine. The control part includes a preparatory operation part controlling the laser processing machine so as to start a preparatory operation for the laser processing if a preparatory operation command is output and, a mode switching part switching an operating mode of the laser oscillator between a standard standby mode before carrying out the laser processing and an energy saving mode with less consumed power than the standard standby mode, and the mode switching part controls the discharge tube voltage so as to switch the operating mode to the energy saving mode before the preparatory operation command is output and to start a switching operation of the operating mode from the energy saving mode to the standard standby mode when the preparatory operation command is output.

Abstract: An apparatus and method that reduces laser speckle by using stimulated Raman scattering in an optical fiber. The fiber core diameter and length are selected to achieve a desired output color. An adjustable despeckler is formed by combining two optical fibers in parallel and adjusting the amount of light in each path.

Abstract: A surface emitting laser diode comprises a substrate, a lower reflector formed over the substrate, an active layer formed over the lower reflector, an upper reflector formed over the active layer, a current restrict structure including a current confinement region surrounded by insulation region. The current restrict structure is disposed in an upper reflector or between an active layer and the upper reflector, and an upper electrode formed over the upper reflector includes an aperture which corresponds to an emission region from which light is emitted in a first direction perpendicular to a surface of a substrate. The emission region and the current restrict structure including the current confinement region are selectively configured to obtain high single transverse mode, stabilized polarization direction, isotropic beam cross section and small divergence angle, while allowing the device to be manufactured with high yield rate.

Abstract: A system includes a modulatable source and matched modal filter. The modulatable source is associated with a plurality of source modes to provide a generated signal. The matched modal filter is coupled to the modulatable source to receive the generated signal. Filter modes are to match the source modes. The matched modal filter is coupleable to a link fiber to provide a signal to the link fiber. The filter modes are to match a subset of link fiber modes to couple the plurality of filter modes to the link fiber.

Abstract: A method for quasi-synchronous tuning of laser wavelength or frequency of grating external-cavity laser and a corresponding laser are provided. A grating or mirror is rotated around a quasi-synchronous tuning point (Pq) to achieve the quasi-synchronous tuning of frequency selections by grating and resonance cavity, wherein, on the xOy coordinate plane, from the perspective of actual physical space of the laser, the rotation center Pq(xq, yq) satisfying the quasi-synchronous tuning condition can be considered as being extended from the rotation center P0(x0, y0) under the conventional synchronous tuning condition to the region enclosed by two parabolas near P0. According to the present disclosure, approximately-synchronous tuning of laser is achieved with simple and flexible designs.

Abstract: An apparatus comprising: a processor for determining if a laser is operating in a single-mode state and for determining the degree to which one of one or more tunable parameters for the laser must be adjusted so that laser operates in a single-mode state if not operating in a single-mode state, wherein the one or more tunable parameters include the following parameters: the laser current and the wavelength of the output light. The apparatus may include a laser and/or a holographic storage medium. Also provided is a method for determining if a laser is operating in a single-mode state and for determining the degree to which one of one or more tunable parameters for the laser must be adjusted so that laser operates in a single-mode state if not operating in a single-mode state.

Abstract: An enhancement cavity includes a plurality of focusing mirrors, at least one of which defines a central aperture having a diameter greater than 1 mm. The mirrors are configured to form an optical pathway for closed reflection and transmission of the optical pulse within the enhancement cavity. Ring-shaped optical pulses having a peak intensity at a radius greater than 0.5 mm from a central axis are directed into the enhancement cavity. Accordingly, the peak intensity of the optical pulse is distributed so as to circumscribe the central apertures in the apertured mirrors, and the mirrors are structured to focus the pulse about the aperture toward a central spot area where the pulse is focused to a high intensity.

Abstract: A driver circuit configured to generate a drive signal for an optical source comprises an overshoot controller that provides an amount of overshoot for a given logic state of the drive signal as a function of a duration of at least one previous logic state of the drive signal. The drive signal may alternate between a first logic state associated with a first operating mode of the optical source and a second logic state associated with a second operating mode of the optical source. The overshoot controller may be configured to provide amounts of overshoot for respective instances of the first logic state that are proportional to the durations of their respective immediately preceding second logic states. The driver circuit may be implemented in a heat-assisted magnetic recording system in which the optical source alternates between on and off states associated with respective magnetic write and magnetic read modes.

Abstract: A laser resonator is provided that includes a cavity bounded by an end mirror and output coupler, and one or more gain media between the end mirror and output coupler. The laser resonator also includes a modal corrector mirror between the end mirror and output coupler. The modal corrector mirror includes a controllable-profile faceplate including an optically-treated front surface, and an array of static actuators. Each static actuator includes an adjustable element, and a compliant mechanism located between the adjustable element and faceplate. The adjustable element is configured to exert a selectable, localized push-pull force on the faceplate via the compliant mechanism, and the compliant mechanism is configured to scale the respective force.

Abstract: The method of the invention is intended for manufacturing a laser diode with improved light-emitting characteristics. The method consists of providing certain components of a laser diode such as a wide-aperture lasing medium that has an active emitting layer with a first end and a second end, a DPH-mode reorganizer that contains a core and a plurality of nanogrooves made in the core and arranged in a pattern that accomplishes a given function and locally changes the refractive index of the core. The method further includes the steps of forming a semitransparent mirror on the second end of the active lasing medium and aligning the first end of the active emitting layer with the core of the DPH-mode reorganizer, thus forming a resonator of the laser diode. In the resonator, the light applied from the laser-active medium bounces back and forth between the DPH-mode reorganizer and the partially reflecting mirror, thereby enhancing stimulated emission.

Abstract: The invention relates to a laser light source for generating narrow-band laser radiation with high coherence, comprising a laser diode (1), which forms an internal resonator (4), and an external resonator (7) coupled to the internal resonator (4). The object of the invention is to improve a laser source of the kind such that it generates narrow-band and coherent laser radiation with high output power and at the same time with high long-term stability. Furthermore, the laser light source is to be produced in a cost-effective manner. The object is achieved by the invention in that the laser diode (1) runs in an operating mode in which multimode laser radiation is generated, comprising a plurality of spectrally neighboring resonance modes (9) of the external resonator (7). The resonance modes are selected by adapting the spectral characteristics of the external (7) and internal (4) resonators.

Abstract: The invention relates to a laser source with an external cavity generating a useful laser beam (Fu), that comprises at least one laser diode DL (10) mounted in an extended optical cavity (30, 82) defined between two reflecting surfaces (92, 48) forming an optical path for a laser beam Fd generated by the laser diode DL, a mode selection filter (44, 86) in the optical path of the cavity for selecting a resonance mode from a range of resonance modes of the laser beam in the cavity.

Abstract: Provided is a vertical cavity surface emitting laser that includes a plurality of laminated semiconductor layers including an active layer and that oscillates at a wavelength ?1, wherein a resonator is formed by upper and lower multilayer reflecting mirrors has a structure that generates a longitudinal multimode, and the first active layer is arranged at a position shifted from a standing wave loop of the first longitudinal mode. According to the vertical cavity surface emitting laser capable of suppressing oscillation of the second longitudinal mode with a large gain and capable of single longitudinal mode oscillation based on the first longitudinal mode, the longitudinal mode spacing is narrowed by increasing the length of the resonator for single transverse mode oscillation at a high output, and the single longitudinal mode oscillation is possible even if longitudinal multimode oscillation occurs.

Abstract: To make it possible to use a type I nonlinear optical crystal or a quasi phase matching element as a third harmonic generation crystal there is provided a semiconductor laser, a solid state laser medium that outputs a fundamental wave, a second harmonic generation crystal that outputs a second harmonic wave from the fundamental wave, and a third harmonic generation crystal that outputs a third harmonic wave from the fundamental wave and the second harmonic wave. A quasi phase matching elements is utilized as the second harmonic generation crystal. It is possible to use a type I nonlinear optical crystal or a quasi phase matching element as the third harmonic generation crystal.

Abstract: Methods and apparatus for improved single-mode selection in a quantum cascade laser. In one example, a distributed feedback grating incorporates both index-coupling and loss-coupling components. The loss-coupling component facilitates selection of one mode from two possible emission modes by periodically incorporating a thin layer of “lossy” semiconductor material on top of the active region to introduce a sufficiently large loss difference between the two modes. The lossy layer is doped to a level sufficient to induce considerable free-carrier absorption losses for one of the two modes while allowing sufficient gain for the other of the two modes. In alternative implementations, the highly-doped layer may be replaced by other low-dimensional structures such as quantum wells, quantum wires, and quantum dots with significant engineered intraband absorption to selectively increase the free-carrier absorption losses for one of multiple possible modes so as to facilitate single-mode operation.

Abstract: Devices and techniques for locking a laser in frequency by locking a reference laser to a reference frequency and an optical interferometer to the reference laser and by locking the laser to a selected frequency produced by the optical interferometer.

Abstract: A laser includes a pump source that provides pump energy at a first wavelength and a laser cavity. The laser cavity includes a laser gain medium that receives the pump energy from the pump source and creates gain at a second wavelength different from the first wavelength, and a mode stripping portion coupled to the laser gain medium. The mode stripping portion causes the laser cavity to have a low Fresnel number so as to allow only the lowest-order fiber mode to resonate in the laser cavity. Higher-order fiber modes are discriminated against so as to generate a laser output having a substantially diffraction limited beam in a single transverse mode at the second wavelength.

Abstract: A laser apparatus comprises an amplifier including at least one of a MOPA and a MOPO each of which amplifies a single-longitudinal or multiple-longitudinal mode laser light, an amplifiable agent of the amplifier being a molecular gas, a master oscillator constructed from a semiconductor laser being able to oscillate a single-longitudinal or multiple-longitudinal mode laser light of which wavelength is within one or more amplification lines of the amplifier; and a controller executing a wave shape control adjusting a pulse shape and/or a pulse output timing of a single-longitudinal or multiple-longitudinal mode laser light outputted from the master oscillator.

Abstract: Laser diode mode techniques are described. In one or more implementations, one or more laser diodes of a computing device are caused to operate below a lasing threshold to illuminate at least part of a physical surroundings of the computing device. One or more images of the illuminated physical surroundings are captured by a camera of the computing device and one or more inputs are recognized from the captured one or more images for interaction with a user interface displayed by the computing device.

Abstract: A laser (100) for outputting laser radiation includes a lasing material (110) in a resonant cavity (20) adapted for supporting a given lasing mode of oscillation. The laser (100) furthermore has at least one laser mirror (124) including a transparent portion for transmitting only a part of a beam of the laser (100) substantially smaller than the dimension of the beam of the laser (100) and the laser (100) includes a mode switching device (120) adapted to induce a change in the transmitted part of the beam, for altering the given lasing mode. A corresponding laser mirror (124), controller and a method for controlling a laser (100) also are described.

Abstract: An apparatus comprising: a processor for determining if a laser is operating in a single-mode state and for determining the degree to which one of one or more tunable parameters for the laser must be adjusted so that laser operates in a single-mode state if not operating in a single-mode state, wherein the one or more tunable parameters include the following parameters: the laser current and the wavelength of the output light. The apparatus may include a laser and/or a holographic storage medium. Also provided is a method for determining if a laser is operating in a single-mode state and for determining the degree to which one of one or more tunable parameters for the laser must be adjusted so that laser operates in a single-mode state if not operating in a single-mode state.

Abstract: Laser light wavelength control is provided by periodically predicting a next position of a light controlling prism using a model of the prism's motion characteristics. The prediction is then updated if a measurement of laser output wavelength is obtained. However, because the predictions are made without waiting for a measurement, they can be made more frequently than the laser firing repetition rate and the prism can be repositioned at discrete points in time which can occur more frequently than the laser firing events. This also reduces performance degradation which may be caused by being one pulse behind a laser measurement and the resultant laser control signal being applied.

Abstract: A tunable laser device (1) comprises integrally formed first and second ridge waveguides (5, 6). A longitudinally extending ridge (12) defines first and second light guiding regions (19, 20) of the first and second waveguides (5, 6) A plurality of first and second slots (27, 28) extending laterally in the ridge (12) adjacent the first and second waveguides (5, 6), produce first and second mirror loss spectra of the respective first and second waveguides (5, 6) with minimum peak values at respective first and second wavelength values. The spacing between the second slots (28) is different to that between the first slots (27) so that with one exception the minimum peak values of the first and second mirror loss spectrum occur at different wavelength values. The first and second waveguides (5, 6) are independently pumped with variable currents to selectively vary the common wavelength at which the minimum peak values of the first and second mirror loss spectra occur to produce Vernier tuning of the device.

Abstract: Provided is a fiber laser including a mode filter for selectively attenuating, among modes included in laser light propagating through a multi-mode fiber, any mode other than a radially polarized mode. Among the modes included in the laser light propagating through the multi-mode fiber, the fiber laser causes the radially polarized mode to resonate, so as to emit radially polarized laser light. The mode filter includes a long-period fiber grating obtained by writing, to a multi-mode fiber capable of guiding the radially polarized mode, a grating for selectively attenuating any waveguide mode other than the radially polarized mode.

Abstract: A wavelength tunable system including a laser having a lasing cavity and an external cavity, the cavities having a common optical axis; a reflective grating fixed in the external cavity; a collimating lens between the lasing cavity and the reflective grating; and an adjustable reflective mirror defining one end of the external cavity and optically coupled to the fixed reflective grating, the adjustable reflective mirror pivots about the fixed reflective grating, and a method of use as defined herein.

Abstract: A laser light source comprises a semiconductor laser adapted for pulsed operation, a partially transmitting wavelength selective light reflector. The semiconductor laser comprises a front facet and a back facet. The front facet and the back facet define an internal laser cavity. The internal laser cavity comprises a laser active medium. The partially transmitting wavelength selective light reflector has a peak reflectivity within a gain bandwidth of said laser active medium. The wavelength selective light reflector and the back facet define an external laser cavity. A roundtrip time of light in the external laser cavity is about 20 nanoseconds or less. A full width half maximum bandwidth of the wavelength selective light reflector is adapted to accommodate at least 12 longitudinal modes of the internal laser cavity and at least 250 longitudinal modes of the external laser cavity.

Abstract: A single-mode, etched facet distributed Bragg reflector laser includes an AlGaInAs/InP laser cavity, a front mirror stack with multiple Fabry-Perot elements, a rear DBR reflector, and a rear detector. The front mirror stack elements and the rear reflector elements include input and output etched facets, and the laser cavity is an etched ridge cavity, all formed from an epitaxial wafer by a two-step lithography and CAIBE process.

Abstract: A pulsed light generator of the invention includes: an excitation light source; a fiber grating into which excitation light from the excitation light source enters; a rare-earth doped optical fiber optically coupled with the fiber grating, in which a rare-earth element is doped into a core, serving as an optical transmitting section; an optical switch including a deflection element for causing a Q-switching operation; a first optical fiber that causes light from the rare-earth doped optical fiber to enter into the optical switch; and a second optical fiber for waveguiding pulsed light output from the optical switch. One surface side of the optical switch, into which light enters, is subjected to anti-reflection treatment with a reflectance with respect to a wavelength of the pulsed light output from the optical switch being 0.1% or less.

Abstract: A mode-locked laser employs a coupled-polarization scheme for efficient longitudinal pumping by reshaped laser diode bars. One or more dielectric polarizers are configured to reflect a pumping wavelength having a first polarization and to reflect a lasing wavelength having a second polarization. An asymmetric cavity provides relatively large beam spot sizes in gain medium to permit efficient coupling to a volume pumped by a laser diode bar. The cavity can include a collimation region with a controlled beam spot size for insertion of a saturable absorber and dispersion components. Beam spot size is selected to provide stable mode locking based on Kerr lensing. Pulse durations of less than 100 fs can be achieved in Yb:KGW.

Abstract: A pulsed laser for machining, has a mode switch, e.g. Q-switch device (15, 30, 40), in a resonant optical cavity (20) capable of supporting a given lasing mode, e.g. a transverse mode of oscillation when lasing action is started, arranged to induce, e.g. temporarily, a localized change, e.g. loss, in the cavity. The latter alters the given lasing mode, e.g. causes the oscillation to hop to a higher transverse mode temporarily, which on its hand may be extinguished by an aperture limiting diaphragm (5) or equivalent and subsequently reduce the induced loss temporarily, to return the oscillation to the given transverse mode and output the laser pulse. A modulator can be used for inducing the temporary loss for a first transverse lasing mode and extinguishing the higher transverse mode with a diaphragm. The induced loss can be over a localized area much smaller than the dimensions of a beam of the laser, so that a miniaturized modulator can be used. In this way pulsed operation may be achieved.

Abstract: Techniques and devices based on optical resonators made of nonlinear optical materials and nonlinear wave mixing to generate RF or microwave oscillations and optical comb signals.

Abstract: The light-enhancing system of the invention comprises a laser diode in which a fully reflecting mirror and/or a partially reflecting mirror of the laser diode is made in the form of digital planar holography (DPH) incorporating a mode-reorganization function that decreases divergence and improves brightness of the output beam of the system by suppressing high-order modes and gaining low-order modes, or mode. The holographic elements are made in the form of rectangular grooves that can be manufactured as binary features reproduced by methods of nanolithography or nanoimprinting.

Abstract: Methods and apparatus for improved single-mode selection in a quantum cascade laser. In one example, a distributed feedback grating incorporates both index-coupling and loss-coupling components. The loss-coupling component facilitates selection of one mode from two possible emission modes by periodically incorporating a thin layer of “lossy” semiconductor material on top of the active region to introduce a sufficiently large loss difference between the two modes. The lossy layer is doped to a level sufficient to induce considerable free-carrier absorption losses for one of the two modes while allowing sufficient gain for the other of the two modes. In alternative implementations, the highly-doped layer may be replaced by other low-dimensional structures such as quantum wells, quantum wires, and quantum dots with significant engineered intraband absorption to selectively increase the free-carrier absorption losses for one of multiple possible modes so as to facilitate single-mode operation.

Abstract: A high power single mode fiber laser system is configured with an active fiber including coextending multimode core (MM) and cladding around the MM core. The MM core is doped with one or more ions selected from rare earth and transitional metals and has a bottleneck cross in accordance with one aspect of the disclosure. The bottleneck cross-section includes a relatively small uniformly dimensioned input end region, a frustoconical region and a relatively large uniformly dimensioned amplifying region. The refractive step index of the MM core is configured with a central dip shaped and dimensioned along the input region so as not to disturb a Gaussian field profile of fundamental mode, gradually transform the Gaussian field profile into the ring profile of the fundamental mode and support the latter along the amplifying region.

Abstract: There is provided a solid-state laser device including: a resonator; a solid-state laser medium disposed in the resonator; an excitation section that irradiates an excitation beam into the solid-state laser medium; a mode selector that controls transverse modes of oscillating light in the resonator; and a movement section that moves the mode selector along the resonator optical axis direction.

Abstract: Diode lasers type of devices with good coupling between field distribution and gain are disclosed. A single element has a flat field distribution that couples with the uniform current injection in a contact region. A multi element array having almost flat field distribution in each element and almost equal amplitude for the field intensity in all elements is provided. Injection by multiple contacts couples well with the overall field distribution. Also, the lasers are stable against filament formation and mode switching.

Abstract: Provided is a resonator of a hybrid laser diode. The resonator includes: a substrate including a semiconductor layer where a hybrid waveguide, a multi-mode waveguide, and a single mode waveguide are connected in series; a compound semiconductor waveguide, provided on the hybrid waveguide of the semiconductor layer, having a tapered coupling structure at one end of the compound semiconductor waveguide, the tapered coupling structure overlapping the multi-mode waveguide partially; and a reflection part provided on one end of the single mode waveguide. The multi-mode waveguide has a narrower width than the hybrid waveguide and the single mode waveguide has a narrower width than the multi-mode waveguide.

Abstract: A planar laser gain medium and laser system. The novel laser gain medium includes an active core having a high aspect ratio cross-section with a fast-axis dimension and a slow-axis dimension, signal claddings adapted to form reflective boundaries at fast-axis boundaries of the core, and a material adapted to minimize reflections at slow-axis boundaries of the core. In an illustrative embodiment, the laser gain medium is an optical fiber. The core and claddings form a waveguide adapted to control modes propagating in the fast-axis direction. When the laser gain medium is employed as a laser oscillator, a high reflectivity mirror and an outcoupler are positioned at opposite ends of the core to form a laser resonator adapted to control modes in the slow-axis direction.

Abstract: A laser cavity structure is disclosed which pertains to laser resonator geometries possessing circular symmetry, such as in the case of disk or spherical lasers. The disclosed invention utilizes a very-high finesse Bragg reflector (VHF-BR) thin film reflectors of many layer pairs of very small refractive index difference, the VHF-BR deposited on a surface of revolution, thereby forming an optical cavity. These dielectric reflectors are disposed in such a way as to allow selection of preferred low order modes and suppression of parasitic modes while allowing a high cavity Q factor for preferred modes. The invention disclosed, in its preferred embodiments, is seen as particularly useful in applications requiring high efficiency in the production and coupling of coherent radiation. This is accomplished in a cavity design that is relatively compact and economical.

Abstract: The present invention relates to a light source apparatus having a structure to enable a short pulse optical output with high pulse energy or a high pulse peak equivalent to that of a Q switch laser light source. The light source apparatus comprises a seed light source, a pre-stage optical amplifier, a subsequent-stage optical amplifier, and a control section. After the pulse light outputted from the seed light source is amplified by the pre-stage optical amplifier, the pulse light is amplified further by the subsequent-stage optical amplifier. In the subsequent-stage optical amplifier, a ring-type resonator is constituted by an optical coupler, an optical coupler, an optical amplification waveguide, an optical isolator, an optical coupler, an optical waveguide, a lens, a Q switch, a lens, and an optical waveguide that are disposed sequentially on the propagation path of the pulse light.

Abstract: A surface emitting semiconductor laser includes a substrate, a lower reflective mirror formed on the substrate, an active layer formed on the lower reflective mirror, an upper reflective mirror formed on the active layer, an optical mode controlling layer formed between the lower reflective mirror and the upper reflective mirror, and a current confining layer formed between the lower reflective mirror and the upper reflective mirror. The active layer emits light. The upper reflective mirror forms a resonator between the lower reflective mirror and the upper reflective mirror. In the optical mode controlling layer, an opening is formed for selectively absorbing or reflecting off light that is emitted in the active layer. The optical mode controlling layer optically controls mode of laser light. The current confining layer confines current that is applied during driving.

Abstract: Methods and apparatus for broad tuning of single wavelength quantum cascade lasers and the use of light output from such lasers for highly sensitive detection of trace gases such as nitrogen dioxide, acetylene, and vapors of explosives such as trinitrotoluene (TNT) and triacetone triperoxide (TATP) and TATP's precursors including acetone and hydrogen peroxide. These methods and apparatus are also suitable for high sensitivity, high selectivity detection of other chemical compounds including chemical warfare agents and toxic industrial chemicals. A quantum cascade laser (QCL) system that better achieves single mode, continuous, mode-hop free tuning for use in L-PAS (laser photoacoustic spectroscopy) by independently coordinating gain chip current, diffraction grating angle and external cavity length is described. An all mechanical method that achieves similar performance is also described. Additionally, methods for improving the sensor performance by critical selection of wavelengths are presented.

Abstract: Systems and methods of generating a tunable laser beam are disclosed. An example method includes: generating coherent optical beams from a plurality of semiconductor optical amplifiers (SOAs); combining the coherent optical beams into a combined coherent optical beam; and tuning the combined beam to a selected frequency range to output a coherent optical beam having only the selected frequency range. In some embodiments, the SOAs are arranged in parallel within a resonant cavity, and each coherent optical beam has a different center wavelength that overlaps in bandwidth with another one of the coherent optical beams.

Abstract: A planar laser gain medium and laser system. The novel laser gain medium includes an active core having a high aspect ratio cross-section with a fast-axis dimension and a slow-axis dimension, signal claddings adapted to form reflective boundaries at fast-axis boundaries of the core, and a material adapted to minimize reflections at slow-axis boundaries of the core. In an illustrative embodiment, the laser gain medium is an optical fiber. The core and claddings form a waveguide adapted to control modes propagating in the fast-axis direction. When the laser gain medium is employed as a laser oscillator, a high reflectivity mirror and an outcoupler are positioned at opposite ends of the core to form a laser resonator adapted to control modes in the slow-axis direction.

Abstract: A laser comprising: a resonator cavity defined by at least two reflectors, wherein the at least two reflectors are highly reflective at a plurality of fundamental wavelengths; a laser medium disposed in the resonator cavity capable of generating plurality of fundamental wavelengths; an optical pump source for energizing the laser medium, thereby causing laser light at the plurality of fundamental wavelengths to resonate in the resonator cavity simultaneously; and a nonlinear material located in said resonator cavity capable of simultaneously converting each of the plurality of wavelengths of laser light to generate converted laser light having a plurality of converted wavelengths, said converted wavelengths being derived from but different to the fundamental wavelengths; wherein the non-linear material is at least partially phase matched to nonlinearly convert the frequencies of each of the fundamental wavelengths simultaneously such that a plurality of converted wavelengths are able to be simultaneously gene

Abstract: A laser light source 1 is provided with an output mirror 11, a laser medium 12, a light beam diameter adjuster 13, an aperture 14, a reflection mirror 15, a drive unit 21, and a control unit 22, and outputs laser oscillation light 31 from the output mirror 11 to the outside. The laser resonator is configured so that the reflection mirror 15 and the output mirror 11 are disposed so as to be opposed to each other with the laser medium 12 placed therebetween. The reflection mirror 15 is configured such that it gives amplitude or phase variations to respective positions in the section of a light beam when the light is reflected, and the reflection mirror presents a amplitude or phase variation distribution in accordance with control from the outside, and determines the transverse mode of the laser oscillation light 31 based on the amplitude or phase variation distribution. Thus, a laser light source capable of easily controlling the transverse mode of the laser oscillation light can be realized.

Abstract: The invention relates to a laser source with an external cavity generating a useful laser beam (Fu), that comprises at least one laser diode DL (10) mounted in an extended optical cavity (30, 82) defined between two reflecting surfaces (92, 48) forming an optical path for a laser beam Fd generated by the laser diode DL, a mode selection filter (44, 86) in the optical path of the cavity for selecting a resonance mode from a range of resonance modes of the laser beam in the cavity.

Abstract: Provided is a device capable of oscillating a plurality of oscillation modes within a laser medium for obtaining a fundamental wave output which is easy in output scaling and high in luminance, thereby enabling a second harmonic conversion which is high in efficiency. The device includes: a laser medium (5) that is planar, has a waveguide structure in a thickness direction of a cross-section that is perpendicular to an optical axis (6), and has a cyclic lens effect in a direction perpendicular to the optical axis (6) and the thickness direction; a clad (4) that is bonded onto one surface of the laser medium (5); and heat sink (3) that is bonded onto one surface side of the laser medium (5) through the clad (4), and in the device, a laser oscillation includes a laser oscillation that oscillates in a waveguide mode of the laser medium (5), and a laser oscillation that oscillates in a plurality of resonator modes that are generated by a cyclic lens effect of the laser medium (5).

Abstract: Key technologies have been developed in realizing single longitudinal mode CW operation with a regular standing-wave cavity for intracavity frequency doubling and intracavity frequency conversions, so as to produce all solid-state, true cw devices with operation over wide spectral ranges including green, blue and UV. In one method laser arrangement, a beam expander (23 or 41) is applied to render a large mode waist and an improved beam divergence so as to greatly reduce the insertion losses for intracavity optical elements (17, 18 or 44). In another method laser arrangement, when spatial hole burning interference effect is minimized by using a pump head (12) with a thin gain zone (2) in contact with an end cavity mirror, then a low resolving-power spectral filter with low loss can be utilized.