Abstract: A fiber laser and an optical device for controlling polarization and outputting single polarized light are provided in a simple structure. The fiber laser includes a solid-state laser fiber (3) doped with a rare earth element, a pump light source (1) for exciting the solid-state laser fiber, a reflective element (2) having wavelength dependency, and a wavelength conversion element (4) arranged at the output side of the solid-state laser fiber away from the reflective element at a specified distance along the solid-state laser fiber, in which an end face of the wavelength conversion element (4) is inclined to an optical axis.

Abstract: A method and circuit is disclosed for a laser system wherein the power of the laser signal is kept at a constant near optimum value and a portion of an frequency doubled output signal is monitored and detected so that noise within the frequency doubled output signal can be minimized. A feedback signal is used to dither the temperature of a frequency doubled crystal so as to minimize the noise in the frequency doubled output signal.

Abstract: This invention relates to a wavelength tunable light source, comprising a main resonator, having a first and a second mirrored end, defining an effective cavity length, i.e. an optical beam path length of a resonant mode of the cavity, an optical gain element, having a first and a second opposing end surface, said second surface being positioned within said main resonator, a mirror element constituting said second mirrored end, and a dispersive focusing resonator element, being positioned along a beam path between said second end surface and said mirror element, whereby said effective cavity length of said main resonator is arranged to be varied.

Abstract: A method of operating a laser projection system is provided. The projection system comprises an external cavity laser, an optical intensity monitor, laser projection optics, and a controller. The external cavity laser comprises a laser diode, an intra-cavity wavelength conversion device, and a wavelength selective element. According to the method, the position of the wavelength selective element is adjusted relative to an optical axis Z of the external cavity laser to optimize output intensity. Specifically, the position of the wavelength selective element is adjusted by (i) tilting the wavelength selective element about its wavelength selective axis Y to reflect a wavelength of interest along an optimum path in an XZ plane of the external laser cavity and (ii) tipping the wavelength selective element about its wavelength insensitive axis X to reflect the wavelength of interest along an optimum path in a YZ plane of the external laser cavity. Additional embodiments are disclosed and claimed.

Abstract: A wavelength conversion element includes a second harmonic wave generating element provided with an entrance surface and an emission surface, a function of converting an incident fundamental wave into a second harmonic wave with a different wavelength and emitting the second harmonic wave, and a cyclic polarization inversion structure configured so as to be able to match a phase of the second harmonic wave in a pseudo manner, and a first wavelength dispersive optical element disposed on the entrance surface side of the second harmonic wave generating element, having a first diffraction surface for diffracting an incident light beam with a diffraction angle increasing in accordance with a wavelength of an incident light beam to disperse the incident light beam by the wavelength of the incident light beam, and for emitting the light beam dispersed in the first diffraction surface towards the second harmonic wave generating element.

Abstract: A laser generator includes a generation means for pumping by a pumping light source (7) a pumping medium (3) to generate a fundamental-wave laser beam, an output sensor (6) for measuring average output power or pulse energy of the fundamental-wave laser beam, a wavelength-conversion element (5), arranged on an optical path for the fundamental-wave laser beam, for converting the fundamental-wave laser beam into its higher-harmonic-wave laser beam, and a controller (9) for memorizing a determination value set to a value lower than a breakage threshold for average output power or pulse energy of the laser beam converted by the wavelength-conversion element (5), and for, when the measurement value becomes not lower than the determination value, controlling the output power of the fundamental-wave laser beam to be a value lower than the breakage threshold; thereby, the beam intensity through the wavelength-conversion element (5) never exceeds the breakage threshold, and thus breakage of the wavelength-conversion e

Abstract: The present invention concerns a laser light source device capable of multiwavelength oscillation. This laser light source device is provided with a laser light source; a laser cavity including a fiber, a first fiber grating provided at a side of the fiber toward the laser light source and having a plurality of reflection peaks, and a second fiber grating provided at a light emission end of the fiber and having a plurality of reflection peaks; a wavelength converter for converting a fundamental wave emitted from the laser cavity into a harmonic wave; a reflection wavelength varying unit capable of shifting the reflection wavelengths of the reflection peaks of the second fiber grating; and a controller for controlling phase matching conditions of the wavelength converter. Intervals between adjacent reflection peaks of the first fiber grating are different from those between adjacent reflection peaks of the second fiber grating.

Abstract: A method and apparatus for modulating a particular light source used for laser display are provided. The apparatus includes a digital modulator digitally modulating light output from a semiconductor laser to a frequency higher than a repetition frequency required for laser image display; and a pixel brightness adjustor inserting at least one high-speed pulse into a period of the modulated output light, which is required for a single pixel, and adjusting a brightness of the pixel by adjusting the number of the inserted high-speed pulses.

Abstract: A light source device includes a semiconductor laser, and a drive circuit supplying the semiconductor laser with a pulsed drive current, and in the semiconductor laser, a laser emitting element and a free wheel diode are formed on the same substrate, and a cathode of the free wheel diode is connected to a current input terminal of the laser emitting element, and an anode of the free wheel diode is connected to a current output terminal of the laser emitting element.

Abstract: A wavelength converter comprising an arsenic sulfide (As—S) chalcogenide glass fiber coupled to an optical parametric oscillator (OPO) crystal and a laser system using an OPO crystal coupled to an As—S fiber are provided. The OPO receives pump laser radiation from a pump laser and emits laser radiation at a wavelength that is longer than the pump laser radiation. The laser radiation that is emitted from the OPO is input into the As—S fiber, which in turn converts the input wavelength from the OPO to a desired wavelength, for example, a wavelength beyond about 4.4 ?m. In an exemplary embodiment, the OPO comprises a periodically poled lithium niobate (PPLN) crystal. The As—S fiber can include any suitable type of optical fiber, such as a conventional core clad fiber, a photonic crystal fiber, or a microstructured fiber.

Abstract: A laser device includes: an amplifying medium (1, 7) adapted to generate a fundamental wavelength laser beam (13); a birefringent non-linear medium (3, 20, 20) for doubling the fundamental wavelength laser beam to generate a harmonic wavelength laser beam (14); a polarizing medium (1b, 5, 6, 2, 8, 9, 16, 20) for selecting a fundamental wavelength laser beam polarization, the polarizing medium being such that the fundamental wave at its output remains parallel to the fundamental wave at its input. The invention is characterized in that the polarizing medium (1b, 5, 6, 2, 8, 9, 16, 20) has an output side (2b) perpendicular to the fundamental wave exiting the polarizing medium. The amplifying medium, the birefringent non-linear medium are mutually integral so as to constitute a monolithic resonant cavity.

Abstract: A wavelength converter comprising an arsenic sulfide (As—S) chalcogenide glass fiber coupled to an optical parametric oscillator (OPO) crystal and a laser system using an OPO crystal coupled to an As—S fiber are provided. The OPO receives pump laser radiation from a pump laser and emits laser radiation at a wavelength that is longer than the pump laser radiation. The laser radiation that is emitted from the OPO is input into the As—S fiber, which in turn converts the input wavelength from the OPO to a desired wavelength, for example, a wavelength beyond about 4.4 ?m. In an exemplary embodiment, the OPO comprises a periodically poled lithium niobate (PPLN) crystal. The As—S fiber can include any suitable type of optical fiber, such as a conventional core clad fiber, a photonic crystal fiber, or a microstructured fiber.

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 light source device includes: a laser light source emitting a laser beam of a prescribed wavelength; a nonlinear optical element, disposed facing a light emergence surface of the laser light sources which converts an emission wavelength of the laser beam emitted from the laser light source and causes the laser beam to emerge; a volume phase grating, disposed facing an emergence surface of the laser beam of the converted wavelength converted by the nonlinear optical element, which has formed in an interior thereof a Bragg grating structure which selectively reflects a laser beam of an emission wavelength; and a first dielectric multilayer, provided on a light emergence surface of the volume phase gratings which transmits the laser beam of the converted wavelength and reflects the laser beam of the emission wavelength.

Abstract: It is aimed to suppress a local increase of an energy density per unit time in a nonlinear crystal. A fundamental wave emitted from a fundamental wave laser light source is condensed by a condenser lens and incident on a nonlinear crystal 11 having a poled structure. By displacing a focus position of a fundamental wave 50 by means of a scanning mirror 21, a local increase of the energy density per unit time in the nonlinear crystal 11 is suppressed.

Abstract: The invention provides a laser system (100) wherein the output may be selected from two or more different wavelengths of output laser light. The system (100) comprises a laser capable of having at least two different wavelengths of laser light resonating in the cavity (105) simultaneously. One of the frequencies is generated by a Raman crystal (135) which shifts the frequency of light generated by the lasing medium (125). A tunable non-linear medium (140), such as LBO, is provided in the cavity for selectively frequency converting at least one of the at least two different wavelengths of laser light. The conversion may be SHG, SFG or DFG for example. A tuner (145) is provided to tune the non-linear medium to select the particular wavelength to convert. Temperature tuning or angle tuning of the non-linear medium can be used. A Q switch (130) may also be provided in the cavity.

Abstract: A laser device, includes: a fundamental wave generating portion configured to generate a plurality of fundamental waves having wavelengths which are different from each other in at least one set thereof, the fundamental wave generating portion having a semiconductor laser having a plurality of luminous points, and a Bragg reflection structure; and a nonlinear optical element in which a poling structure adapted to pseudophase matching for the wavelengths of the plurality of fundamental waves emitted from the fundamental wave generating portion, respectively, is formed variatively along a propagating direction of the plurality of fundamental waves.

Abstract: Techniques for generating terahertz (THz) radiation are provided in which each nonlinear crystal in an array of such crystals is coupled to one or more corresponding waveguides such that any THz radiation generated in any single crystal is coupled into that crystal's THz waveguide structure. After the THz radiation is generated in the crystals and coupled into the waveguides, the individual THz signals may be coherently combined to form a single THz signal (non-coherent configurations are provided as well). Crystal-waveguide arrays embodying the techniques can be used to implement efficient, robust, and compact THz sources suitable for applications such as security screening, medical imaging, quality control and process monitoring in manufacturing operations, and package and container inspection.

Abstract: The present invention coherent multiple-stage optical rectification terahertz wave generator discloses the generation of single-cycle terahertz radiation with two-stage optical rectification in GaSe crystals. By adjusting the time delay between the pump pulses employed to excite the two stages, the terahertz radiation from the second GaSe crystal can constructively superpose with the seeding terahertz field from the first stage. The high mutual coherence between the two terahertz radiation fields is ensured with the coherent optical rectification process and can be further used to synthesize a desired spectral profile of output coherent THz radiation. The technique is also useful for generating high amplitude single-cycle terahertz pulses, not limited by the pulse walk-off effect from group velocity mismatch in the nonlinear optical crystal used.

Abstract: Particular embodiments of the present invention relate generally to methods of controlling an optical package comprising a semiconductor laser, a spectral filter, and a wavelength conversion device. The spectral filter and the wavelength conversion device collectively define a wavelength transfer function comprising a transmission bandwidth component attributable to the spectral filter and a conversion bandwidth component attributable to the wavelength conversion device. The transmission bandwidth component of the wavelength transfer function is less than one free spectral range of the semiconductor laser. The method comprises directing the native laser output through the spectral filter and the wavelength conversion device and tuning the semiconductor laser to modulate the intensity of a wavelength-converted laser output of the optical package by shifting the native wavelength spectrum by less than one free spectral range of the semiconductor laser. Additional embodiments are disclosed and claimed.

Abstract: Fiber lasers for producing Band I wavelengths include a laser cavity having an optical fiber with specific parameters in length and thickness and doping concentration, and having high reflectivities. Examples show the feasibility of producing such fiber lasers. Fiber lasers for producing Band IV wavelengths include a depolarized laser oscillator, at least one amplifier and a polarizer. Depolarized laser oscillator is an inherently depolarized CW laser, or a depolarized laser diode, which is depolarized by a depolarizer. Additional fiber lasers in accordance with embodiments of the present invention include a double clad active optical fiber having a pump power entry point for sending pump energy through the active optical fiber in a first direction, and a loop portion at a second end of the fiber for sending pump energy through the active optical fiber in a second direction which is opposite to the first direction.

Abstract: A wavelength converting laser device includes a laser diode producing laser light and including an optical resonator having a pair of facing reflectors, including a reflecting surface having a shape reducing loss in the optical resonator, with regard to a specific horizontal transverse mode of laser light as compared to the loss in the optical resonator for other horizontal transverse modes, and a wavelength converter for converting the laser light into harmonic light.

Abstract: It is an object to enable control according to an optimum temperature condition for a wavelength conversion device.

Abstract: Semiconductor electrooptic medium shows behavior different from a medium based on quantum confined Stark Effect. A preferred embodiment has a type-II heterojunction, selected such, that, in zero electric field, an electron and a hole are localized on the opposite sides of the heterojunction having a negligible or very small overlap of the wave functions, and correspondingly, a zero or a very small exciton oscillator strength. Applying an electric field results in squeezing of the wave functions to the heterojunction which strongly increases the overlap of the electron and the hole wave functions, resulting in a strong increase of the exciton oscillator strength. Another embodiment of the novel electrooptic medium includes a heterojunction between a layer and a superlattice, wherein an electron and a hole in the zero electric field are localized on the opposite sides of the heterojunction, the latter being effectively a type-II heterojunction.

Abstract: A laser light generating apparatus includes a laser light source, a phase-modulator, a signal generating unit configured to generate a modulation signal applied to the phase-modulator, a first external resonator, a second external resonator disposed at the stage succeeding the first external resonator, nonlinear optical elements each provided in the external resonators configured to implement wavelength conversion, an optical path length varying unit for varying the optical path length of each of the external resonators, and a control circuit having a negative feedback arrangement configured to obtain error signals for each of the external resonators, and configured to control the optical path length varying unit using the error signals according to FM sideband method. In the laser light generating apparatus, the external resonators are each held simultaneously in a resonance state by setting the frequency of the modulation signal and by controlling the optical path length of each of the external resonators.

Abstract: Various embodiments include modelocked fiber laser resonators that may be coupled with optical amplifiers. An isolator may separate the laser resonator from the amplifier, although certain embodiments exclude such an isolator. A reflective optical element on one end of the resonator having a relatively low reflectivity may be employed to couple light from the laser resonator to the amplifier. Enhanced pulse-width control may be provided with concatenated sections of both polarization-maintaining and non-polarization-maintaining fibers. Apodized fiber Bragg gratings and integrated fiber polarizers may be also be included in the laser cavity to assist in linearly polarizing the output of the cavity. Very short pulses with a large optical bandwidth may be obtained by matching the dispersion value of the fiber Bragg grating to the inverse of the dispersion of the intra-cavity fiber. Frequency comb sources may be constructed from such modelocked fiber oscillators.

Abstract: A laser light source device includes a laser light source that emits a laser beam as a fundamental wave and an optical wavelength conversion element that converts the fundamental wave into a second harmonic. An optical lens system including a first surface having positive power and a second surface having negative power is arranged between the laser light source and the optical wavelength conversion element. The first surface and the second surface are arranged in order from the laser light source side.

Abstract: A laser light source having a semiconductor laser (102) for outputting pump light, and a laser resonator wherein a solid laser crystal (104) and a non-linear optical crystal (103) are connected by optical contact and a reflection coat (106) and a reflection coat (105) are on the opposed facets of the respective crystals. GdVO4 is the solid laser crystal (104) while LiNbO3 is the non-linear optical crystal (103), and the crystal axis of the solid laser crystal (104) is inclined with respect to the z axis of the non-linear optical crystal (103) within the z-x plane of the non-linear optical crystal (103). The thermal expansion coefficients of the solid laser crystal and of the non-linear optical crystal can be approximated to each other, thereby preventing separation of the bonded laser crystal and non-linear optical crystal due to different thermal expansion coefficients when heat is generated during laser oscillation, which stops laser oscillation.

Abstract: A parametric device having a non-linear material (4) for generating an idler wave and a signal wave (16) in response to a pump wave (14), the pump, idler and signal waves being non-collinear, the device having a cavity (10, 11) resonant at the pump wavelength and means for varying the angle between the propagation directions of the pump and idler waves.

Abstract: Methods and devices for providing a multiwavelength laser which may be used for multicasting and other optical communications uses. The present invention provides a quantum dot based multiwavelength laser with a monolithic gain block. The Fabry-Perot gain block has both upper and lower InP cladding layers. The laser system has a middle quantum dot layer with multiple stacked layers of InAs quantum dots embedded in InGaAsP. When provided with a CW injection current, the laser system produces an output spectra with equally spaced multiple emission peaks. With an input optical data signal applied to the laser system, the laser system duplicates the data in the input signal across multiple different wavelengths.

Abstract: A wavelength conversion laser apparatus including: a laser light source emitting primary wavelength light; a non-linear optical crystal including: a light waveguide region having a first refractivity, the light waveguide region receiving the primary wavelength light to output as secondary wavelength light; and a clad region adjacent to the light waveguide region, the clad region having a second refractivity lower than the first refractivity, wherein at least the light waveguide region has a periodically domain-inverted structure formed such that a domain-inverted period varies in a direction perpendicular to an incident axis of the primary wavelength light; and a mover moving the non-linear optical crystal to change the domain-inverted period on a path where the primary wavelength light incident on the light waveguide region passes.

Abstract: Methods of controlling semiconductor lasers are provided where the semiconductor laser generates a wavelength-modulated output beam ?MOD that is directed towards the input face of a wavelength conversion device. The intensity of a wavelength-converted output ?CONV of the device is monitored as the output beam of the laser is modulated and as the position of the modulated output beam ?MOD on the input face of the wavelength conversion device is varied. A maximum value of the monitored intensity is correlated with optimum coordinates representing the position of the modulated output beam ?MOD on the input face of the wavelength conversion device. The optical package is operated in the data projection mode by directing an intensity-modulated laser beam from the semiconductor laser to the wavelength conversion device using the optimum positional coordinates. Additional embodiments are disclosed and claimed. Laser controllers and projections systems are also provided.

Abstract: A compact optically-pumped solid-state laser designed for efficient nonlinear intracavity frequency conversion into desired wavelengths using periodically poled nonlinear crystals. These crystals contain dopants such as MgO or ZnO and/or have a specified degree of stoichiometry that ensures high reliability. The laser includes a solid-state gain media chip, such as Nd:YVO4, which also provides polarization control of the laser; and a periodically poled nonlinear crystal chip such as PPMgOLN or PPZnOLT for efficient frequency doubling of the fundamental infrared laser beam into the visible wavelength range. The described designs are especially advantageous for obtaining low-cost green and blue laser sources.

Abstract: A laser apparatus in which the elimination of separate optical components to provide intra-cavity polarization and compensation for thermally induced birefringence, and their associated losses, results in an improvement in efficiency and reduction in complexity over prior art designs.

Abstract: According to the present invention, a laser light source comprises plural semiconductor lasers (2), a solid laser (4), a non-linear material (3) as a wavelength conversion element, a reflection coat (5) formed on one facet of the solid laser, and a reflection coat (6) formed on one facet of the non-linear material (3), and the solid laser and the wavelength conversion element are disposed between the both reflection coats to constitute a laser resonator, and plural pump parts (8) in the solid laser (4) which are pumped by the plural semiconductor lasers are separated from each other by 300 ?m or more. Thereby, interference between transverse modes of laser oscillation is avoided, thereby providing a high-power, stable, and compact solid laser light source with which a stable high output power can be obtained.

Abstract: Laser apparatus is disclosed in which fundamental-wavelength optical pulses delivered from a mode-locked laser resonator at a pulse-repetition frequency (PRF) are converted to harmonic-wavelength pulses in an optical delay loop. One example is disclosed in which the harmonic-wavelength pulses are delivered directly from the delay loop. Another example is disclosed in which the harmonic-wavelength pulses are divided by the delay loop into a number of temporally spaced-apart replicas thereof, and the delay loop delivers bursts of replicas of different one of the harmonic wavelength pulses at a burst-repetition frequency equal to or a multiple of the PRF of the resonator.

Abstract: A system and method for optical frequency conversion having asymmetric output include a coherent light apparatus. The coherent light apparatus includes a coherent light source that produces a first coherent light, a frequency converter optically coupled to the coherent light source, and a coupling optic optically coupled between the coherent light source and the frequency converter. The frequency converter converts the first coherent light to a second coherent light at a second frequency and includes an asymmetric frequency converter (AFC) that nonlinearly converts the first coherent light to the second coherent light with the frequency conversion being more efficient in a first direction than in a second direction. A resonant cavity formed about the AFC circulates the first coherent light and transmits the second coherent light propagating in the first direction.

Abstract: A light emitting device including a waveguide having an electrically pumped gain region, a saturable absorber, a nonlinear crystal, an inclined mirror, and a light-concentrating structure. Light pulses emitted from the gain region are reflected by the inclined minor and focused by the light-concentrating structure into the nonlinear crystal in order to generate frequency-converted light pulses. The gain region, the saturable absorber, the light-concentrating structure and the inclined minor are implemented on or in a common substrate. The resulting structure is stable and compact, and allows on-wafer testing of produced emitters. The folded structure allows easy alignment of the nonlinear crystal.

Abstract: A Thulium laser (15) is used to directly drive a ZnGeP2 optical parametric oscillator (30) with a nominal 2 ?m output to generate the 3-5 micron wavelengths. In one embodiment, the ZGP OPO is configured as a linear resonator and in another embodiment the ZGP OPO is configured as a ring resonator. The ring resonator prevents optical feedback to the Thulium laser (15) and eliminates the need for an optical isolator (24). Moreover, the Thulium laser pump (15) is implemented as a Tm:YAlO3 laser in which YAlO is the host for the Thulium YAlO is particularly beneficial as it is a mechanically hard optical material allowing high thermal loading without fracture as well as natural birefringence that can minimize thermal birefringence losses. A longer wavelength transition at 1.99 microns is selected to minimize nonlinear crystal loss. More particularly, a high power, high efficiency Tm:YAlO3 laser repetitively Q-switched at 10 kHz is used to drive a ZnGeP2 OPO.

Abstract: The present invention concerns a laser light source device capable of multiwavelength oscillation. This laser light source device is provided with a laser light source; a laser cavity including a fiber, a first fiber grating provided at a side of the fiber toward the laser light source and having a plurality of reflection peaks, and a second fiber grating provided at a light emission end of the fiber and having a plurality of reflection peaks: a wavelength converter for converting a fundamental wave emitted from the laser cavity into a harmonic wave; a reflection wavelength varying unit capable of shifting the reflection wavelengths of the reflection peaks of the second fiber grating; and a controller for controlling phase matching conditions of the wavelength converter. Intervals between adjacent reflection peaks of the first fiber grating are different from those between adjacent reflection peaks of the second fiber grating.

Abstract: A fiber laser system includes a predominately single spatial mode, linearly polarized master oscillator providing a set of optical pulses and a polarization-maintaining optical isolator optically coupled to the master oscillator. The fiber laser system also includes a fiber amplifier optically coupled to the optical isolator and including a power amplifier comprising a double clad gain fiber, one or more pump lasers, and a pump coupler. The fiber laser system further includes a pulse compression stage optically coupled to the fiber amplifier. The pulse compression stage includes a volume holographic phase grating. Moreover, the fiber laser system includes a nonlinear frequency conversion stage optically coupled to the pulse compression stage.

Abstract: A device for generating light pulses includes a seed laser source for generating input light pulses. An optical pre-amplifier having variable gain receives the input light pulses from the seed laser source. An optical power amplifier receives the light pulses from the optical pre-amplifier and amplifies and compresses the received light pulses. The light pulses are compressed in the optical power amplifier in such a manner that the pulse duration of the output light pulses of the optical power amplifier is tunable via adjusting the gain of the optical pre-amplifier. Wavelength-tunable light pulses are obtained by supplying the output light pulses of the optical power amplifier to a highly non-linear optical fiber.

Abstract: A wavelength conversion module according to the present invention includes an external resonator, a semiconductor laser module and a wavelength conversion device for converting a wavelength of light output from the semiconductor laser module into a shorter wavelength. This wavelength conversion device includes at least one of a nonlinear crystal for generating SFG (Sum-frequency Generation) light and a nonlinear crystal for generating SHG (Second Harmonic Generation) light. Each of the SFG generating element and the SHG generating element of the wavelength conversion device may have a periodically-poled ridge-waveguide structure or a periodically-poled proton-exchanged-waveguide structure.

Abstract: A light source device includes: a light source unit configured to emit light; a wavelength conversion element configured to convert the wavelength of light emitted from the light source unit; a light source housing configured to accommodate at least the light source unit and the wavelength conversion element; and a temperature control unit configured to control temperature of the wavelength conversion element. The temperature control unit is disposed outside the light source housing.

Abstract: In an internal OPO, a substrate comprising a thin film lies along an axis and a first mirror reflects first wavelength light. A gain medium lases and polarizes light entering therein and a Q-switch attenuates and transmits first wavelength light. An HR/HT mirror passes first wavelength light and reflects a second wavelength light, and an OPO rod converts a portion of the first wavelength light into second wavelength light. An output coupler (OC) reflects first wavelength light and passes a portion of second wavelength light, the first wavelength reflecting between the first mirror, the OC and through the gain medium and the Q-switch. The second wavelength light reflects between the HR/HT mirror and OC and through the OPO rod. The invention applies to external OPO as well. The thin film reflects the light towards the gain medium, permitting a lower power lightsource and increasing the efficiency of the gain medium.

Abstract: Particular embodiments of the present invention relate generally to altering the effective conversion efficiency curve of an optical package employing a semiconductor laser and an SHG crystal or other type of wavelength conversion device. For example, according to one embodiment of the present invention, a method of controlling an optical package is provided where the optical package is tuned such that ascending portions of a transmission curve representing a spectral filter are aligned with descending portions of a conversion efficiency curve representing a wavelength conversion device. With the filter and wavelength conversion device so aligned, the optical package is further tuned such that the wavelength of the fundamental laser signal lies within a wavelength range corresponding to aligned portions of the ascending and descending portions of the transmission and conversion efficiency curves. Additional embodiments are disclosed and claimed.

Abstract: According to one embodiment of the present invention, an optical package comprises one or more semiconductor lasers coupled to a wavelength conversion device with adaptive optics. The optical package also comprises a package controller programmed to operate the semiconductor laser and the adaptive optics based on modulated feedback control signals supplied to the wavelength selective section of the semiconductor laser and the adaptive optics. The wavelength control signal supplied to the wavelength selective section of the semiconductor laser may be adjusted based on the modulated wavelength feedback control signal such that the response parameter of the wavelength conversion device is optimized. Similarly, the position control signals supplied to the adaptive optics may be adjusted based on the modulated feedback position control signals such that the response parameter of the wavelength conversion device is optimized.

Abstract: A method is given for aligning an optical package comprising a laser, a wavelength conversion device, at least one adjustable optical component, and at least one actuator. The adjustable optical component may be moved to a command position by applying a pulse width modulated signal to the actuator. The command position represents an optimized alignment of the laser and wavelength conversion device. The actual position of the adjustable may be measured by measuring an output of a position measuring circuit, which may measure the voltage amplitude of an oscillation in a resonator tank circuit during an “off” period of the pulse-width modulated signal. The resonator tank circuit may comprise a capacitive element electrically coupled to the electrically conductive coil. The pulse-width modulated signal may then be adjusted to compensate for any difference in the actual position and the command position of the adjustable optical component. Additional embodiments are disclosed and claimed.

Abstract: A wavelength-agile laser transmitter apparatus and method are provided. The apparatus comprises a pump laser that is configured to output a pump beam at a first (pump) wavelength and an optical parametric oscillator. The optical parametric oscillator comprises a cavity that contains several optical components including a non-linear optical medium, a first, second and third optical elements, and a narrow linewidth filter. The non-linear optical medium is configured to convert light at the first wavelength to light at a second (signal) wavelength and a third (idler) wavelength that are each longer than the first wavelength. Light at the second and third wavelengths is allowed to partially resonate in the optical parametric oscillator, and the output beam of the apparatus corresponds to light at the third wavelength.

Abstract: High-power, diode-pumped solid state (DPSS) pulsed lasers are preferred for applications such as micromachining, via drilling of integrated circuits, and ultraviolet (UV) conversion. Nd:YVO4 (vanadate) lasers are good candidates for high power applications because they feature a high energy absorption coefficient over a wide bandwidth of pumping wavelengths. However, vanadate has poor thermo-mechanical properties, in that the material is stiff and fractures easily when thermally stressed. By optimizing laser parameters and selecting pumping wavelengths and doping a concentration of the gain medium to control the absorption coefficient less than 2 cm?1 such as the pumping wavelength between about 910 nm and about 920 nm, a doped vanadate laser may be enhanced to produce as much as 100 W of output power without fracturing the crystal material, while delivering a 40% reduction in thermal lensing.