Abstract: In a soliton mode-locked solid-state laser apparatus having a resonator which includes therein a solid-state laser medium, a saturable absorption mirror, and a negative group velocity dispersion element, the solid-state laser medium and saturable absorption mirror are disposed in close proximity to each other at a distance not greater than twice a Rayleigh length. Then, the absorption modulation depth ?R of the the saturable absorption mirror is set to a value not less than 0.4%, and the absolute value |D| (D<0) of a total intracavity dispersion amount D when light having a predetermined wavelength makes one round trip in the resonator, which is represented by the following relational expression, is set within a pulse bandwidth in which operation modes other than a fundamental period soliton pulse can be suppressed by the saturable absorption mirror. ? P = 1.

Abstract: A VCSEL includes a substrate having a partially removed portion; a metal-assisted DBR having a metal layer and a first mirror stack, wherein the metal layer is located at the partially removed portion of the substrate; an active region having a plurality of quantum wells over the metal-assisted DBR; and a second mirror stack over the active region, wherein a number of alternating layers of the first mirror stack is substantially smaller than a number typically required for a VCSEL without the integrated metal reflector. Such a metal-assisted DBR is especially useful for a long-wavelength VCSEL on a InP substrate or a red-color VCSEL on a GaAs substrate.

Abstract: A laser source (10) for emitting a set of sequential, different wavelength output beams (12) includes a gain medium (16), a feedback assembly (26) and a control system (30). The gain medium (16) includes a first facet (16A), and the gain medium (16) generates a beam (12A) that exits the first facet (16A). The feedback assembly (26) includes a feedback device (40) and a device mover (42). The feedback device (40) is positioned in the path of the beam (12A) that exits the first facet (16A) and the feedback device (40) redirects at least a portion of the beam (12A) back to the gain medium (16). The device mover (42) continuously adjusts an angle of incidence (?) of the beam (12A) on the feedback device (40). The control system (30) selectively directs pulses of power to the gain medium (16) as the device mover (42) is continuously adjusting the angle of incidence (?) of the beam (12A).

Abstract: A normally opaque waveguide interacting with a drop-filter cavity can be switched to a transparent state when the drop filter is also coupled to a dipole. This dipole induced transparency may be obtained even when the vacuum Rabi frequency of the dipole is much less than the cavity decay rate. The condition for transparency is a large Purcell factor. Dipole induced transparency can be used in quantum repeaters for long distance quantum communication.

Abstract: Various embodiments of the present invention are directed to compact, sub-wavelength optical resonators. In one aspect, an optical resonator comprises two approximately parallel reflective structures positioned and configured to form a resonant cavity. The resonator also includes a fishnet structure disposed within the cavity and oriented approximately parallel to the reflective structures. The resonant cavity is configured with a cavity length that can support resonance with electromagnetic radiation having a fundamental wavelength that is more than twice the cavity length.

Abstract: In accordance with the present invention, a compact laser system with nearly continuous wavelength scanning is presented. In some embodiments, the compact laser system can be scanned over a broad range. In some embodiments, the compact laser system can be scanned at high scan rates. In some embodiments, the compact laser system can have a variable coherence length. In particular, embodiments with wavelength scanning over 140 nm with continuously variable scan rates of up to about 1 nm/?s, and discrete increase in scan rates up to about 10 nm/?s, and variable coherence lengths of from 1 mm to about 30 mm can be achieved.

Abstract: An active layer (18) is formed over a semiconductor substrate having a pair of facets (15A, 15B) mutually facing opposite directions. An upper cladding layer (19) is formed on the active layer, having a refractive index lower than that of the active layer. A diffraction grating (25) is disposed in the upper cladding layer on both sides of a distributed feedback region in a waveguide region (22), the waveguide region extending from one facet to the other of the semiconductor substrate. End regions (22B) are defined at both ends of the waveguide region and the distributed feedback region (22A) is disposed between the end regions. Low refractive index regions (26) are disposed in the upper cladding layer on both sides of each of the end regions of the waveguide region, the low refractive index regions having a refractive index lower than that of the upper cladding layer.

Abstract: A vertical cavity surface emitting laser includes an active layer between a first reflector and a second reflector and at least either the first reflector or the second reflector includes a two-dimensional photonic crystal. The two-dimensional photonic crystal has a structure 106 showing an ununiform effective refractive index distribution in the plane of the reflector to realize both a high reflectivity and transverse mode control at the same time.

Abstract: An active area includes a photonic-crystal optical waveguide formed by periodically arranging a plurality of holes in a primary plane direction of an active-area core layer in an active-area growth portion. A passive area includes a passive optical waveguide formed in a passive-area growth portion. An effective refractive index of a growth structure of the active-area growth portion is larger than an effective refractive index of a growth structure of the passive-area growth portion, and an active layer has a gain at a zero group-velocity point positioned on a high-frequency side of a dispersion curve of the photonic-crystal optical waveguide.

Abstract: The present invention relates to a laser transmitter capable of being configured to transmit one of a plurality of wavelengths. Specifically, the laser transmitter may be reconfigured using the resonance passbands of a tunable microresonator coupled with a fixed grating.

Abstract: The hologram recording technology expected to realize ultrahigh-density information recording is one of the post Blu-ray Disc technology. When we think about developing a drive based on this technology and suitable for consumer electronics, it is considered most desirable from the viewpoint of upward compatibility to solve the problem of the BD-compatibility. The problem in sharing the laser light source between the hologram recording device and the current optical disc device, however, is that the hologram recording requires a high-coherent, single-mode light beam, while the current optical discs requires a low-coherent, multi-mode light beam. In point of the coherence of the light source, the above two cases require the light beams of the characteristics opposite to each other, and this presents an important task.

Abstract: Unidirectionality of lasers is enhanced by forming one or more etched gaps (78, 80) in the laser cavity. The gaps may be provided in any segment of a laser, such as any leg of a ring laser, or in one leg (62) of a V-shaped laser (60). A Brewster angle facet at the distal end of a photonic device coupled to the laser reduces back-reflection into the laser cavity. A distributed Bragg reflector is used at the output of a laser to enhance the side-mode suppression ratio of the laser.

Abstract: The invention relates to an article comprising a length of an optical fiber and a package, the optical fiber comprising a fiber Bragg grating dispersed over a FBG-section of the length of the optical fiber, the package comprising a carrier with a carrier surface for supporting at least a supported part of the optical fiber including the FBG-section. The invention further relates to an apparatus comprising the article, to its use and to a method of manufacturing such an article. The object of the present invention is to seek to provide an optimized (e.g. elongate) package having a relatively low sensitivity to mechanical vibrations from the environment. This is achieved by providing that the carrier surface for supporting the optical fiber comprising a fiber Bragg grating is convex in a longitudinal direction of the optical fiber during use of the article.

Abstract: A laser is disclosed, which is suitable for efficient generation of continuous-wave laser light having a wavelength of about 400 nm or less. The short-wavelength light is generated by first frequency-doubling a fundamental wave, and then sum-frequency mixing the frequency-doubled wave and the fundamental wave. The non-linear interactions are effected by means of quasi-phasematching structures inside a resonant cavity where the fundamental wave is circulating. The sum-frequency mixing is effected using second or higher order quasi-phasematching, which allows for wider domains to be inverted for the quasi-phasematching structure compared to first order quasi-phasematching. Preferably, the sum-frequency mixing is effected using periodically poled stoichiometric lithium tantalate (PPSLT) for second or third order quasi-phasematching.

Abstract: A beam coupler assembly for a fiber laser is disclosed. The assembly includes a housing having a sidewall with an interior surface, an exterior surface, a first end and a second end. A first seal extending from the interior surface of the tubular housing and dividing the housing into a first section and a second section is also provided. The first section and second section are environmentally isolated from one another. However, the first seal is substantially optically neutral. An input collimator unit received within the first end of the sidewall of the housing and into the first section and is releasably coupled thereto. An output collimator unit received within the second end of the sidewall of the housing and into the second section and is also releasably coupled thereto.

Abstract: For increasing the power emitted by surface emitting lasers and for improving the spatial coherence of the laser beam, emitted in particular by disk lasers, microchip lasers and VCSELs having a relatively wide emitting area, the invention proposes to select a low order transverse cavity mode by means of a mirror structure (12) of high reflectivity, and of high angular selectivity. The mirror structure comprises a multilayer (14) receiving the optical beam (24) and a resonant grating mirror (16) following the multilayer and arranged for highly reflecting the optical beam in a narrow angular range at each side of a determined incidence angle.

Abstract: The invention relates to laser system with a laser source and an articulated arm. The articulated arm has an optical arrangement for guiding a laser beam from the laser source along an optical path in the articulated arm to a target location. Within the optical path at least one crossing area (focus or focal point) of the laser beam is provided. The optical arrangement has at least one optical cell with an input window and an output window for passing the laser beam therethrough, wherein the crossing area is positioned within the optical cell. The optical cell has a gas fill with an energy threshold for ionization that is increased in comparison to that of ambient air.

Abstract: An unstable optical resonator for an optically active medium comprising a spherical back mirror and a spherical outcoupling mirror is proposed, and an outcoupling which is asymmetrical in relation to the optical axis takes place therein.

Abstract: A surface-emitting extended cavity laser with intracavity frequency conversion is provided with at least one surface-emitting laser element (1) with multiple layers to obtain laser light at a fundamental frequency, reflector means, spaced from the laser element (1) to form an external cavity (12), a frequency conversion device (3), arranged within the external cavity (12) to generate light at a second frequency and tuneable optical band-pass filter means, arranged within the external cavity (12) and detector means, where said optical band-pass filter means are tuneable upon a signal, which is obtained by the detector means to enable a frequency control at the fundamental frequency.

Abstract: A vertical cavity surface-emitting laser (VCSEL) is disclosed. The VCSEL includes a layer that at least partially defines an optical cavity having an optical axis. The VCSEL further includes a resonant reflector layer extending across at least part of the optical cavity. The resonant reflector layer has a refractive index that does not abruptly change laterally across the optical cavity. The refractive index of the resonant reflector layer includes contributions from a first material having a first refractive index and a second material having a second refractive index. At least one of the first material and the second material includes a polymer.

Abstract: Laser diodes (120) emit laser beams along a vertical YZ plane at different distances from the YZ plane. The beams are collimated in their fast and slow axes, and are redirected by turning mirrors (162) to form a beam stack (130C) traveling along the XZ plane. The beam stack is turned by about 90°, then converged by a focusing lens (174) into an optical fiber (180). A compact assembly is thus provided. Each laser diode (120.i), its collimating optics (154.i, 158.i, i=1,2, . . . ) and its turning mirror (162.i) are rigidly attached to a flat, heat-spreading surface (144.i) and thus remain aligned with each other in thermal cycling.

Abstract: A laser assembly is suitable for coupling laser light into at least one optical fiber. The laser assembly contains a plurality of laser light sources disposed spaced from a light entrance surface of the at least one optical fiber. The laser light sources are divided into at least one group of first laser light sources and at least one group of second laser light sources. An aperture is provided and is suitable for spatially confining the laser light emitted during operation of the laser light sources before being coupled into the at least one optical fiber. A coupling device is provided and is suitable for coupling the laser light during operation of the first and second laser light sources before it enters into the at least one optical fiber.

Abstract: A laser source (10) for generating a continuously wavelength tunable light (12) includes a gain media (16), an optical output coupler (36F), a cavity collimator (38A), a diffraction grating (30), a grating beam (54), and a beam attacher (56). The diffraction grating (30) is spaced apart from the cavity collimator (38A) and the grating (30) cooperates with the optical output coupler (36F) to define an external cavity (32). The grating (30) includes a grating face surface (42A) that is in a grating plane (42B). The beam attacher (56) retains the grating beam (54) and allows the grating beam (54) and the grating (30) to effectively pivot about a pivot axis (33) that is located approximately at an intersection of a pivot plane (50) and the grating plane (42B).

Abstract: In a solid-state laser amplifier including at least two laser-active media in a common laser radiation field, the laser-active media do not form a hard aperture for the laser radiation field. Each of the laser-active media define a plane that is penetrated by the laser radiation field. The laser amplifier includes at least one focusing optical element disposed in the laser radiation field between two adjacent laser-active media. A focal length and a distance of the focusing optical element from the planes of the two adjacent laser-active media are selected such that the planes of the laser-active media are approximately mapped onto each other by a near-field far-field transformation.

Abstract: Double Bragg grating scanner receivers (DBS) and methods thereof based on spinning high-efficiency transmitting or reflecting holograms in photo-thermo-refractive (PTRG) glass provides unlimited field of view while incident angle for all components do not exceed approximately 45 degrees. The devices and methods are highly tolerable to high power laser radiation and has no restriction for the use in any laser systems working in visible and near IR spectral regions. Rate of scanning by DBS is higher compared to known mechanical scanners because the use of thin glass plates with recorded holograms and spinning instead of rocking. The components described herein are holographic optical devices (reflecting and transmitting volume gratings) for visible and near IR spectral regions with absolute diffraction efficiency exceeding approximately 95% and high thermal, optical and mechanical stability.

Abstract: A semiconductor device includes a substrate, a semiconductor layer formed on the substrate, and an optically functional portion formed by using at least a portion of the semiconductor layer. The optically functional portion performs light emission or light reception. The semiconductor device further includes a first driving electrode that is electrically connected to a semiconductor layer on a surface of the optically functional portion, and the first driving electrode drives the optically functional portion. The semiconductor device further includes an encapsulating electrode that is formed on the semiconductor layer to surround periphery of the optically functional portion, and electrically connected to the first driving electrode.

Abstract: A mode-locked laser device includes a Fabry-Perot resonator, a mode-locking element disposed within the resonator, a solid-state laser medium disposed within the resonator, and exciting means for applying excitation light to the solid-state laser medium. The opposite ends of the resonator, the mode-locking element and the solid-state laser medium are disposed to provide an average beam diameter of lasing light of not more than 150 ?m on the mode-locking element and an average beam diameter of the lasing light of not more than 200 ?m within the solid-state laser medium.

Abstract: This invention relates to semiconductor laser apparatus with a structure for reducing the divergence angle of output light and for narrowing the spectral width. The semiconductor laser apparatus has at least a semiconductor laser array, a collimator lens, a path rotator, and an optical element with a reflecting function. The collimator lens collimates a plurality of laser beams from the semiconductor laser array, in a predetermined direction. The path rotator outputs each beam collimated in the predetermined direction, with a predetermined divergence angle in the predetermined direction in a state in which a transverse section of the beam is rotated by about 90°. The optical element is arranged at a position where at least a part of each beam from the path rotator arrives, and constitutes at least a part of an external resonator. This optical element reflects a part of each beam from the path rotator to return the reflected part of each beam to the active layer in the semiconductor laser array.

Abstract: A surface light emitting semiconductor laser element, comprises a substrate, a lower reflector including a semiconductor multi-layer disposed on the substrate, an active layer disposed on the lower reflector, an upper reflector including a semiconductor multi-layer disposed on the active layer, a compound semiconductor layer having a first opening for exposing the upper reflector and extending over the upper reflector, and a metal film having a second opening for exposing the upper reflector disposed inside of the first opening and extending over the compound semiconductor layer, wherein the metal film and the compound semiconductor layer constitute a complex refractive index distribution structure where a complex refractive index is changed from the center of the second opening towards the outside. A method of emitting laser light in a single-peak transverse mode is also provided.

Abstract: A high power laser processing system is disclosed that includes a laser source and at least one optical element. The laser source provides a high power laser illumination of a first wavelength. The optical element includes a substrate that is substantially transparent to the first wavelength illumination, at least one highly reflective coating on a first side of the substrate, and at least one anti-reflective coating on a second side of the substrate.

Abstract: The present invention provides a nitride semiconductor laser element, comprising: a nitride semiconductor structure having a first nitride semiconductor layer, a second nitride semiconductor layer, and an active layer provided between the first and second nitride semiconductor layers; a cavity end face provided to the nitride semiconductor structure; and a protective film having a hexagonal crystal structure, and having a first region provided on a first crystal surface of the nitride semiconductor structure in the cavity end face and a second region provided on a second crystal surface in the surface of at least one of the first and second nitride semiconductor layer, the first and second regions of the protective film are oriented in the same axial direction as that of the respective first and second crystal surfaces.

Abstract: Vertical cavity surface emitting lasers are disclosed, one example of which includes a substrate upon which a lower mirror layer is formed. An active region and upper mirror layer are disposed, in that order, on the lower mirror layer. In particular, the upper mirror layer includes a plurality of DBR layers formed on the active region. The upper mirror layer additionally includes a photonic crystal formed on the plurality of DBR layers and having a periodic structure that contributes to the definition of a central defect. As a consequence of this structure, the photonic crystal has a reflectivity that is wavelength dependent, and the central defect enables the VCSEL to propagate a single mode.

Abstract: An improvement in a method of controlling lasing in a semiconductor laser fabricated in a photonic crystal laser having a plurality of holes into which a birefringent material with low refractive losses and low optical loses with controllable spatial refractive index orientation has been infiltrated comprises the step of rotating the molecular orientation or changing the physical orientation of the birefringent material infiltrated into the holes of the photonic crystal laser to switch cavity modes. The liquid crystal is aligned by use of an alignable photo addressable polymer layer adjacent to the liquid crystal. The cavity modes are optically switched within the laser without any requirement of external energy to maintain the lasing state of the laser, which allows its use as a memory element.

Abstract: A semiconductor laser device with the energy density increased at the focal point and a LD pumped solid-state laser device configured of the particular semiconductor laser device are provided. A stack array laser element for radiating a two-dimensional array of laser beams includes a plurality of parallel laser beam columns each aligned in the form of dotted lines. In front of the stack array laser element, each laser beam column collimated by being refracted in the direction substantially perpendicular to the direction of the dotted line is received, and radiated by turning at right angles to the direction of the laser beams from each emitter or emitter group. In this way, the laser beams are converted into a plurality of substantially ladder-shaped parallel laser beam columns. These parallel laser beam columns are compressed to form parallel laser beam columns in alignment. Each compressed one of parallel laser beam columns is turned at right angles and radiated.

Abstract: Provided is a fiber ring laser capable of obtaining a back-up laser light and standard light having a wavelength continuously tuned in a single mode with equal spacing of 12.5 GHz, 25 GHz, 50 GHz or 100 GHz recommended by ITU-T Recommendation G. 692 & G. 694.1 in a C-band and an L-band using a fiber tunable etalon filter, an air gap etalon filter and a saturable absorber in an optical fiber laser resonator having a serial ring shape using a C-band optical amplifier and an L-band optical amplifier. The fiber ring laser can generate laser light having a wavelength tuned by more than 70 nm, excellent output power flatness and a source spontaneous emission ratio of more than 70 dB in 361 channels with equal spacing of 25 GHz by applying a bias voltage to a voltage-operated piezoelectric element of a tunable etalon filter. A single longitudinal mode operation of the fiber ring laser can be obtained by using a saturable absorber serving as a narrow-bandwidth filter.

Abstract: A photon pair generating device capable of further increasing generation efficiency of a correlation photon pair is provided, the photon pair generating device generating the correlation photon pair by a hyper-parametric scattering. A quantum well is provided in a resonator. An incident light radiated from a light source to the resonator resonates therein and becomes a particular resonator mode. The generation efficiency of the correlation photon pair by the hyper-parametric scattering in the quantum well is enhanced by disposing the quantum well in a position where electric field strength of the light becomes higher by this resonator mode.

Abstract: A gas discharge laser system bandwidth control mechanism and method of operation for controlling bandwidth in a laser output light pulse generated in the gas discharge laser system is disclosed which may comprise a bandwidth controller which may comprise an active bandwidth adjustment mechanism; a controller actively controlling the active bandwidth adjustment mechanism utilizing an algorithm implementing bandwidth thermal transient correction based upon a model of the impact of laser system operation on the wavefront of the laser light pulse being generated and line narrowed in the laser system as it is incident on the bandwidth adjustment mechanism. The controller algorithm may comprises a function of the power deposition history in at least a portion of an optical train of the gas discharge laser system, e.g., a linear function, e.g., a combination of a plurality of decay functions each comprising a respective decay time constant and a respective coefficient.

Abstract: A normally opaque waveguide interacting with a drop-filter cavity can be switched to a transparent state when the drop filter is also coupled to a dipole. This dipole induced transparency may be obtained even when the vacuum Rabi frequency of the dipole is much less than the cavity decay rate. The condition for transparency is a large Purcell factor. Dipole induced transparency can be used in quantum repeaters for long distance quantum communication.

Abstract: The present invention includes a laser amplifier and a method of making the same. The laser amplifier of the present invention includes a gain medium layer having a first index of refraction, and a coupling layer optically coupled to the gain medium. In the various embodiments described herein, the coupling layer can have a second index of refraction less than the first index of refraction. The laser amplifier described herein can also include an evanescent layer disposed between the gain medium and the coupling layer. The evanescent layer can have a third index of refraction less than the second index of refraction. The laser amplifier provides high power, efficient laser resonance through frustrated total internal reflection and total internal reflection while simultaneously providing for the minimization of waste heat in the gain medium layer.

Abstract: Surface emitting laser arrays with intra-cavity harmonic generation are coupled to an optical system that extracts harmonic light in both directions from an intra-cavity nonlinear optical material in such a way that the focusing properties of the light beams are matched.

Abstract: A semiconductor laser device includes a semiconductor laser body including a resonator and having a front end face and a rear end face facing each other, the resonator being located between the front end face and the rear end face. The front end face emits principal laser light. A reflectance control film is disposed on the front end face or the rear end face of the semiconductor laser body and is made up of either an aluminum oxide film or a five-layer film including the aluminum oxide film disposed such that it is the layer in the five-layer film farthest from the front end face or the rear end face. A silicon oxide film is disposed on the aluminum oxide film of the reflectance control film and has a thickness of 20 nm or less.

Abstract: An optical resonator has an internal cavity with an output coupler, an end mirror, and one or more active mirror amplifiers (AMAs) that are arranged in a manner to form a laser radiation propagation path within the cavity which substantially has the form of a star polygon trajectory.

Abstract: A Distributed Bragg Reflector (DBR) that has relatively low light absorption, relatively low electrical resistance, and/or relatively good thermal conductivity. The DBR may include a first mirror layer and a second mirror layer, with an interface therebetween. A step transition is provided in the aluminum concentration and in the doping concentration at or near the interface between the first mirror layer and the second mirror layer. To reduce optical absorption, the interface between the first and second mirror layers may be positioned at or near a null in the optical electric field within the DBR. A graded junction may also be provided. The graded junction may be more lightly doped, have a graded aluminum concentration, and may be placed at or near a peak in the optical electric field.

Abstract: Systems, configurations and methods of using an ultrafast, self-starting, mode-locked laser are provided. The systems, devices and methods of using stable, self-starting mode-locked lasers, can be compact, use fewer optical elements and have energies sufficient for most micro-processing and micro-structuring applications. The large spectral bandwidth of ultra-short (femtosecond) laser pulses can be used in laser sensing applications, micro-machining, time-resolved experiments, where short-lived transient species can be observed in biological or chemical reactions. Terahertz radiation can be generated using ultrashort pulses and used for imaging applications.

Abstract: The subject of the invention is a laser comprising a semiconductor active medium with a population inversion lifetime ?c and a resonant cavity with a lifetime of the photons in the cavity ?p. The cavity includes means for being longitudinally monomode and means so that ?p>?c, such as for example a very long cavity, so as to obtain a laser with a very low intrinsic noise.

Abstract: An external-cavity laser light source apparatus includes a plurality of laser light emission modules, each including a first mirror, a second mirror reflecting fundamental wave light toward the first mirror, a lasing medium emitting the fundamental wave light, a wavelength converter performing wavelength conversion on incident fundamental wave light to produce first converted light and non-converted light. A third mirror reflects second converted light to produce reflected, converted light, the second converted light being wavelength-converted light produced when the non-converted light is reflected off the second mirror and incident again on the wavelength converter. The plurality of modules are disposed so that the first converted light beams exit the modules in the same direction and the reflected, converted light beams exiting the modules approach each other. A deflector may deflect the reflected, converted light beams exiting from the modules in the same exit direction as the first converted light.

Abstract: A distributed feedback semiconductor laser may have (1) a controlled complex-coupling coefficient which is not affected by grating etching depth variation, and (2) facet power asymmetry with no facet reflection which eliminates a random effect of facet grating phase. The device comprises a multiple-quantum-well active region, and a complex-coupled grating formed by periodically etching grooves through a part of the active region. The semiconductor materials for a barrier layer where the groove etching is to be stopped, a regrown layer in the etched groove, and a laser cladding layer, are chosen all the same, so as to form an active grating entirely buried in the same material, providing a complex-coupling coefficient which is defined independently of the etching depth. Facet power symmetry may also be provided by composing the laser cavity of two sections (“front” and “back” sections) having different (“front” and “back”) Bragg wavelengths.

Abstract: A laser chamber is provided that increases power, initiation, and discharge efficiency over single chamber lasers by providing a multi-fold laser chamber, protrusions, discharge segmentation and inversion techniques.

Abstract: An optical configuration to illuminate an etalon in a laser wavemeter with a minimum level of light intensity. The system includes optical components to direct a portion of the laser output beam representing the entire cross section of the beam, through an etalon positioned in an etalon housing and onto a photodetector. A first lens condenses the size of the beam sample, and a second lens re-collimates the beam which then passes into the etalon housing, ensuring that all of the spatial components of the beam are adequately sampled. A diffractive diffusing element is incorporated into the optical path. In a preferred embodiment, the diffractive diffusing element is placed within the etalon housing between said plano-concave lens and the etalon. In another preferred embodiment, the diffusing element is located up stream but outside the housing in the optical path.

Abstract: Continuously tunable and precisely wavelength-switchable fiber lasers combine fiber Bragg gratings and the transmissive filtering properties of high finesse fiber Fabry-Perot filters. This laser arrangement adapts to multiple wavelength ranges based on the selections of fiber Bragg grating and gain medium and their arrangement to create a wavelength-modulatable and simultaneously rapidly wavelength-switchable narrow linewidth all-fiber laser design. This laser arrangement further results in narrow-linewidth outputs with fast switching speeds between the selected wavelengths.