Abstract: In a shifting algorithm for an optically nonlinear crystal arranged to frequency-convert beam of radiation, the location of one or more defects in the crystal is recorded as an exclusion zone. The location of the beam is stepped incrementally over a surface around a closed or open loop path in increments less than a beam dimension. The path is arranged such that the beam does not enter the exclusion zone.

Abstract: A device comprising a conversion channel including: a first end configured to accept ambient electromagnetic radiation, the ambient electromagnetic radiation having an initial frequency, a second end configured to allow the ambient electromagnetic radiation to exit, and at least two opposing walls connecting the first end and the second end, wherein the at least two opposing walls include one or more crystals, the at least two opposing walls being separated by at least one-half of a wave length; wherein when the ambient electromagnetic radiation interacts with the one or more crystals of the at least two opposing side walls, the initial frequency of the ambient electromagnetic radiation being repeatedly increased to an optimal frequency is provided. Furthermore, an associated method is also provided.

Abstract: A method and system for converting one frequency into another include a MOPA configuration radiating a light at a first frequency which is coupled into a frequency conversion unit. Further included are a control unit operative to monitor the other frequency and a pump unit operative to vary its output power provided that the monitored frequency does not substantially match a reference value stored in the control unit. The output power of the pump unit varies while the master oscillator scans its cavity in search for the desired resonant frequency.

Abstract: An optical package is provided comprising a laser diode and a wavelength conversion device. The laser diode and the wavelength conversion device define an external laser cavity and the wavelength conversion device is tilted relative to the output face of the laser diode to define a tilt angle ? that is less than approximately 85°. The input face of the wavelength conversion device comprises a pair of tapered facets and a microlens. The pair of tapered facets and the microlens are defined on the input face such that they share respective portions of the facial waveguide region on the input face, with the tapered facets occupying peripheral portions of the facial waveguide region on the input face and the microlens occupying an interior portion of the facial waveguide region on the input face. Each of the pair of tapered facets define a facet angle ? within the facial waveguide region that is less than the facet angle ? and is greater than approximately 45°. Additional embodiments are disclosed and claimed.

Abstract: Adhesive-free bond non-linear optical (NLO) components, devices and systems including one or more engineered quasi non-critical phase matched or contra-phase matched NLO crystal doublets. Such systems and devices advantageously increase the efficiency of NLO frequency conversion and improve beam quality. Devices are applicable to any uniaxial and biaxial NLO crystals in a wide range of wavelengths, e.g., from far ultraviolet to visible to far infrared. Devices employing engineered AFB NLO components according to certain embodiments include any conventional frequency converting architectures. Systems and methods are also provided to unambiguously determine and correct walk-off for any arbitrary uniaxial and biaxial crystal orientation.

Abstract: A nonlinear optical device is provided. More specifically, a wavelength conversion device package with less optical loss stabilizes optical alignment under an external environmental change, for example, in a temperature variation by providing a temperature regulating block and a temperature sensor to an optical oscillator and a wavelength modulator and fixing a flexible optical transmitter to the optical oscillator and the wavelength modulator. The wavelength conversion device package includes an optical oscillator comprising a light source for emitting a light; a flexible optical transmitter for transferring the light emitted from the optical oscillator to a wavelength modulator; and the wavelength modulator for receiving the light from the optical transmitter and radiating a wavelength-modulated light.

Abstract: Disclosed herein is an optically locked photon echo apparatus and method, which can solve the problem of limited echo efficiency and can overcome constraints on the conventional storage time being limited to the spin dephasing time. The optically locked photon echo apparatus of the present invention includes a nonlinear optical medium and an optical pulse generation unit. The nonlinear optical medium is provided with three energy levels |1>, |2>, and |3>, and is configured to receive optical pulses from an optical pulse generation unit and generate output light (E) which satisfies a phase matching condition. The optical pulse generation unit is configured to generate five or more optical pulses which resonate between the energy levels of the optical medium.

Abstract: A device for increasing the spectral bandwidth of optical pulses, comprises a hollow fiber waveguide, optical components for focusing the beam into the hollow fiber waveguide and for re-collimating the beam at the exit of the hollow fiber waveguide, the hollow fiber waveguide being contained in an air-tight chamber filled with a gas at a given pressure; the length of the hollow fiber is such that, for a given input pulse energy and gas pressure, the energy contained in a fundamental propagation mode of the optical pulses that has minimum propagation losses exhibits substantially periodic oscillations over the full length of the hollow fiber waveguide and reaches a local maximum at the output end of the said hollow fiber waveguide.

Abstract: Disclosed is a color adjusting arrangement comprising: i) a first wavelength converting material arranged to receive ambient light and capable of converting ambient light of a first wavelength range into light of a second wavelength range, and/or reflecting ambient light of said second wavelength range, said second wavelength range being part of the visible light spectrum; and ii) a complementary wavelength converting material arranged to receive ambient light and capable of converting part of said ambient light into light of a complementary wavelength range, which is complementary to said second wavelength range, and arranged to allow mixing of light of said second wavelength range and said complementary wavelength range; such that light of said second wavelength range that is emitted and/or reflected by said first wavelength converting material and light of said complementary wavelength range is mixed when leaving the color adjusting arrangement towards a viewing position, the light leaving the color adjust

Abstract: This invention is directed to a new class of nonlinear optical device (NLO). For this purpose, in one aspect of this invention, a nonlinear optical device including a first nonlinear optical grating is presented. According to one version of the invention, the first nonlinear optical grating comprises a plurality of adjacent nonlinear optical units arranged in series. Each NLO unit has a single crystal segment and a polycrystalline segment. The single crystal segment is composed of a nonlinear optical crystal material and has its length adapted to provide the nonlinear optical effect. The polycrystalline segments are adapted in length to compensate the phase mismatch among the waves that occur in the single crystal segment.

Abstract: An electrical device for the utilization of electromagnetic energy, the device comprising a substrate and an aligned array of electromagnetic energy responsive nanotubes supported by and extending through the substrate, which nanotubes are arranged to respond to electromagnetic energy.

Abstract: An enhanced wavelength-converting structure is disclosed. The enhanced wavelength-converting structure includes a substrate, a wavelength-converting layer arranged next to the substrate, and a wavelength-selective reflecting layer arranged next to the wavelength-converting layer. The wavelength-converting layer converts the first light into the second light. A part of the second light radiating backward to the light source is further reflected toward the substrate by the wavelength-selective reflecting layer to form the enhanced second light by combining with another part of the second light radiating toward the substrate.

Abstract: A thermally switched optical downconverting (TSOD) filter is a self-regulating device including a downconverter that converts incoming light at a variety of wavelengths into longer-wavelength radiation and then directs it using one or more bandblock filters in either the inward or outward direction, depending on the temperature of the device. This control over the flow of radiant energy occurs independently of the thermal conductivity or insulating properties of the device and may or may not preserve the image and color properties of incoming visible light. The TSOD filter is energy-efficient as it can be used to regulate the internal temperature and illumination of buildings, vehicles, and other structures without the need for an external power supply or operator signals. The TSOD filter has unique aesthetic and optical properties not found in traditional windows, skylights, stained glass, light fixtures, glass blocks, bricks, or walls.

Abstract: There is provides a wavelength conversion apparatus for converting a wavelength of input signal light and for outputting output signal light of the converted wavelength. The apparatus includes a first and a second nonlinear mediums. The first nonlinear medium receives a first input light and outputs a first output light having a wavelength which is longer than that of the first input light, the wavelength being dependent on optical power of the first input light. The second nonlinear medium receives a second input light and a light output by a light source and outputs a second output light having a wavelength dependent on the wavelengths of the second input light and the light. The first output light is input as the second input light to the second nonlinear medium or the second output light is input as the first input light to the first nonlinear medium.

Abstract: A wavelength conversion laser device includes a laser light source which emits a laser beam, two reflective surfaces which reflect therefrom a laser beam, a wavelength converter provided between the two reflective surfaces, which converts a laser beam into a wavelength-converted laser beam, and condensing optics which condense the laser beams to be injected between the two reflective surfaces, wherein at least one of the two reflective surfaces has a curvature for reflecting a laser beam to be re-injected into the wavelength converter between the two reflective surfaces repeatedly while forming multi paths of laser beams injected into the wavelength converter at different incident angles, and the condensing optics are arranged to disperse beam waists of the laser beams in the wavelength converter, which reciprocate between the two reflective surfaces.

Abstract: In one embodiment a system and method for harvesting optical energy employ an optical energy harvesting fiber including a core having active elements that absorb light at one wavelength of range of wavelengths and emit light at one or more different wavelengths, a guiding structure that guides the emitted light along a length of the fiber, and a cladding that surrounds the core.

Abstract: A new deep blue extended super continuum light source is provided wherein said super continuum at least extends to a low wavelength border ?low low below 480 nm comprising a pump source which operates at a at least one wavelength ?pump and produces pump pulses of a duration (full width half maximum) longer than 0.1 picoseconds with a repetition rate higher than 1 MHz, and a peak power ?peak, and a micro-structured optical transmission medium having at least one wavelength of zero dispersion ?zero, and for the parameters for said pump source exhibiting a second order dispersion parameter ?2, and a non-linear parameter ? arranged so that the optical transmission medium exhibits a modulation instability gain extending to wavelengths above a wavelength ?high?1300 nm and a phase match between ?1ow and a wavelength ?match??high, wherein the pump is adapted to provide energy within the region of anomalous dispersion of the transmission medium.

Abstract: In a blue extended super continuum light source, when pulses of partly coherent monochromatic “pump” radiation of essentially constant amplitude are propagating through a microstructure fiber medium within a region of anomalous dispersion of the medium, then, provided the medium has a finite nonlinear coefficient of the index of refraction, the pump pulse is subject to a modulation instability. This results in formation of a train of narrow pulses with Tera Hertz repetition rate. Phase match between red shifted Raman solitons generated by the pump pulse and energy shed by the pump pulse at all frequencies with a group velocity below the pump pulse group velocity may lead to the formation of Cherenkov radiation. The solitons may seed Cherenkov radiation at different wavelengths depending on the actual fiber parameters. This allows extension of generated super continuum light beyond the four wave mixing limit when applying picosecond or nanosecond pump pulses.

Abstract: A system for adaptive laser scanning correction includes a laser scanner coupled to a controller. The controller develops control signals for the laser scanner for a directed scan pattern that is modified to compensate for a characteristic scan-pattern distortion introduced by the laser scanner. The laser scanner responds to the control signals to provide an actual scan pattern approaching a target scan-pattern shape. The system may be useful for ophthalmologic laser surgery and other applications requiring precise control over scan pattern shape and a high scanning speed.

Abstract: The present invention relates to a light source apparatus that has a base structure capable of generating SC light and further having a structure that enables the shaping of the spectral waveform of the SC light, power adjustment of the SC light, or adjustment of the frequency of repetition of the pulse train that contains the SC light. For example, a light source apparatus that enables shaping of spectral waveforms comprises a seed light source that emits seed light which is a pulse train or continuous light; an optical fiber that generates SC light from the seed light, and spectrum shaping means for completely or partially changing the spectral waveform of the SC light. The shaping of the spectral waveform changes the maximum power of the seed light by changing the optical coupling efficiency of the seed light source and optical fiber, for example, thereby suitably deforms the spectrum of the SC light.

Abstract: A method of inducing a periodic variation of nonlinearity value in a sample of ferroelectric material comprises arranging a pair of electrodes on opposite faces of the sample, one electrode defining a desired pattern of nonlinearity variation, applying a pre-bias voltage across the sample for a predetermined time using the electrodes, the pre-bias voltage being less than the coercive field of the ferroelectric material; and after the predetermined time, applying a current-controlled poling voltage across the sample using the electrodes, to produce domain inversion in the sample according to the desired pattern of nonlinearity variation. The pre-bias voltage may be 75% of the coercive field or more, and applied for a pre-determined time between 1 and 100 seconds.

Abstract: Particular embodiments of the present disclosure bring an SHG crystal, or other type of wavelength conversion device, into close proximity with a laser source to eliminate the need for coupling optics, reduce the number of package components, and reduce package volume. According to one embodiment of the present disclosure, an optical package is provided comprising a laser source and a wavelength conversion device. The laser source is positioned such that the output face of the laser source is proximity-coupled to a waveguide portion of the input face of the wavelength conversion device. The input face of the wavelength conversion device comprises an ?-cut facet and ?-cut facet. The ?-cut facet of the input face is oriented at a horizontal angle ?, relative to the waveguide of the wavelength conversion device to permit proximity coupling of the output face of the laser source and the input face of the wavelength conversion device.

Abstract: The invention relates to an optical wavelength conversion device adapted to receive at least one first pump beam (?1) as an input and emitting a different wavelength output beam (?S), which includes: an optical cavity (CE); an optically non-linear medium (CNL) placed inside the optical cavity; and a control system (BA1) for controlling said optical cavity having the wavelength of the first pump beam; said control system being adapted to receive, as an input, a first signal (S1) representing the power stored in the cavity having said first wavelength and a second signal (S2) representing the power of the output beam. The invention also relates to a coherent light source comprising such a device and one or two pump laser sources (L1, L2).

Abstract: A wavelength conversion laser light source includes: an element temperature switching section that switches a temperature of the wavelength conversion element according to a harmonic wave output value as set in an output setting device, and the element temperature switching section for switching a temperature of a wavelength conversion element according to a harmonic wave output level as set in the output setting device, wherein the element temperature switch section includes an element temperature holding section that holds the wavelength conversion element at the temperature as switched by the element temperature switching section.

Abstract: A nonlinear harmonic generation system is provided. The nonlinear harmonic generation system includes a waveguide channel receives and propagates electromagnetic signals. A resonant cavity is coupled to the waveguide channel. The resonant cavity structure includes a plurality of resonant modes into which electromagnetic energy is coupled during the operation of the system. One of the resonant modes includes a resonant frequency that changes during operation of the system to reach either an input-signal frequency or a harmonic frequency for a majority of the time in which harmonic generation is occurring. Both reflected and harmonic fields are emitted back into the waveguide channel so as to allow efficient harmonic generation at a specified critical input power.

Abstract: A wavelength conversion laser light source 100 has: a laser light source configured to generate fundamental wave laser light; and a wavelength conversion element 101 provided with a periodic polarization reversal structure configured to convert the fundamental wave laser light which is incident onto the periodic polarization reversal structure into different laser light in wavelength wherein the wavelength conversion element includes different polarization reversal regions in period; and a polarization reversal axis 102 of at least one of the polarization reversal regions is inclined with respect to an incident optical path of the fundamental wave laser light on the wavelength conversion element.

Abstract: A method of optical communication includes generating an amplified optical signal from at least a portion of a first optical signal having a first carrier wavelength, ?1. The amplified optical signal is applied to Brillouin media to stimulate generation of a Brillouin effect signal at a wavelength ?2. The Brillouin effect signal is modulated to produce a second optical signal having a second carrier wavelength, ?2. In one embodiment, the first optical signal is a downstream optical signal and the second optical signal is an upstream optical signal of a passive optical network.

Abstract: A nonlinear optical crystal having a chemical formula of YiLajAlkB16O48, where 2.8?i?3.2, 0.8?j?1.2, i and j sum to about four, and k is about 12 is provided. The nonlinear optical crystal is useful for nonlinear optical applications including frequency conversion. Nonlinear optical crystals in a specific embodiment are characterized by UV blocking materials (e.g., some transition metals and lanthanides) at concentrations of less than 1,000 parts per million, providing high transmittance over portions of the UV spectrum (e.g., 175-360 nm).

Abstract: The present invention relates to a frequency shifter in an optical path containing a pulsed laser source, and it is characterized in that it comprises at least one frequency shifter (12, 13) containing an optical propagation medium, the optical path length of which is modified according to the desired frequency shift during at least one pulse among n consecutive pulses from the laser, where n?1.

Abstract: A device for reducing time distortion generated in light pulses by an optical frequency converter including at least one nonlinear optical component (4) having a nonlinear optical susceptibility ? of about 2 or 3, the converter being capable of receiving at least one incident pulse light beam (2), the incident light pulses having a duration ?t0, an optical frequency ?0±??0 and an intensity I0(t), and of generating, by frequency conversion, at least one output pulse beam (3), the output light pulses having a duration ?t1, an optical frequency ?1±??1 different from ?0±??0, and an intensity I1(t). The time distortion-reducing device includes a pre-compensation linear time filter (5) provided on the path of the incident beam (2), and capable of reducing the intensity time distortions generated in the frequency-converted output light pulses to at least one pre-compensation intensity Icomp.

Abstract: A terahertz wave generating apparatus 2 includes an excitation light source 10, a transmission-type diffraction grating 32, a variable imaging optical system 61, and a nonlinear optical crystal 70. The transmission-type diffraction grating 32 inputs pulsed excitation light output from the excitation light source 10, and diffracts and outputs the pulsed excitation light. In the transmission-type diffraction grating 32, its orientation is variable with a straight central axis, that is parallel to the grooves and passing through an incident position of a principal ray of the pulsed excitation light. The variable imaging optical system 61 is configured to input the pulsed excitation light diffracted to be output by the transmission-type diffraction grating 32, to form an image of the pulsed excitation light by the transmission-type diffraction grating 32, and its imaging magnification is variable.

Abstract: A light emitting apparatus has a radiation source for emitting short wavelength radiation. A down conversion material receives and down converts at least some of the short wavelength radiation emitted by the radiation source and back transfers a portion of the received and down converted radiation. An optic device adjacent the down conversion material at least partially surrounds the radiation source. The optic device is configured to extract at least some of the back transferred radiation. A sealant substantially seals a space between the radiation source and the optic device.

Abstract: An optical phase lock loop (OPLL) system is disclosed that includes a master external cavity laser (ECL), and a substantially identical slave ECL. The master and slave ECLs are fabricated using a planar semiconductor device with waveguide-integrated planar Bragg gratings (PBG). Both the master and slave ECLs have a narrow linewidth and a low frequency-noise. Each of the ECLs has their own controller-modulator circuits for thermal tuning or electrical tuning via direct modulation. A laser-select-logic (LSL) module receives and processes a filtered phase error signal from a loop filter coupled to an electronic PLL device, and directs the processed phase error signal to one or both of the master and slave controller-modulators according to a logical determination of a required mode of operation of the OPLL system in order to achieve a stable and identical phase performance of the master and the slave ECLs.

Abstract: A fluoroberyllium borate non-linear optical single crystal is represented by a molecular formula of MBe2BO3F2, wherein M is Rb or Cs. The crystal can be grown by the flux method comprising the steps of mixing a fluoroberyllium borate compound and a flux in proportion, heating the mixture up to 750-800° C., keeping at this temperature and then cooling it to the temperature of 2-10° C. above the saturating point to obtain a fluoroberyllium borate solution at high temperature; putting the seed crystal fixed on the end of a crystal hanging bar into the fluoroberyllium borate solution at high temperature, rotating the crystal hanging bar, cooling the melt solution to its saturating point, then cooling it again slowly, pulling the obtained crystal out of the solution surface, cooling it to room temperature, then obtaining the present fluoroberyllium borate non-linear optical crystal.

Abstract: In accordance with the present invention, a bulk optic material (for example, silica) is processed to form a spatially microstructured element, such as a photonic bandgap (PBG) structure. An ultra-short laser pulse source is used as an input signal that is applied to the bulk optic PBG structure to generate an enhanced continuum output. The PBG structure may comprise any type of one-, two- or three-dimensional grating structure, where the selected structure will dictate the type(s) of enhancement(s) that are present in the generated continuum—generally in the form of a broadened continuum and/or the inclusion of one or peaks in the continuum. The use of a relatively small-dimensioned bulk material allows for the continuum to be generated without the need for any type of optical confinement (waveguide). In one embodiment, the bulk PBG structure may be is subjected to one or more additional processes (such as UV exposure, electromagnetic field application, etc.

Abstract: A device for extending the lifetime of a frequency-converting non-linear optical system (19) subjected to the radiation of an intense laser beam includes two plates (2, 3) with flat and parallel surfaces angled on the beam and elements for transverse rotation of the plates (2, 3) suitable for changing the angle of inclination of the first plate in an angular range (i20±?i2) to move the incident beam relative to the optical system (19), while minimising the amplitude of movement of the output beam (37, 47) on the angular inclination range (i20±?i2) of the first plate. The application of the device in a non-linear optical source including one or more non-linear crystals (1, 16) is also described.

Abstract: A wavelength conversion element is provided with a substrate including a nonlinear optical single crystal having a periodically poled structure, wherein a visible light transmittance of the substrate is 85% or higher when ultraviolet light is irradiated to the substrate. Further, a laser light having an average output of 1 W or more is outputted by shortening a wavelength of inputted laser light having a wavelength of 640 nm to 2000 nm. By improving visible light transmission characteristics when the ultraviolet light is irradiated in this way, a breakdown of crystal can be prevented and a stabilization of output characteristics at high output can be realized. As a result, an absorption of green light induced by ultraviolet light can also be suppressed and a saturation of output and the breakdown of crystal can be avoided.

Abstract: A wavelength conversion laser is provided with a pair of fundamental wave reflecting surfaces for reflecting a fundamental wave to define a plurality of fundamental wave paths passing a wavelength conversion element at different angles, and a control unit for controlling wavelength conversion efficiencies so that the wavelength conversion efficiency on a specific one of the plurality of fundamental wave paths extending in different directions between the pair of fundamental wave reflecting surfaces is highest.

Abstract: Methods and systems are described using a non-linear optical system comprising a laser and a light delivery system comprising a single mode fiber, a mode converter, and a high order mode fiber, wherein the light delivery system that receives light from the source and provides a structured free-space beam having an embedded Gaussian beam. The light delivery system functions to illuminate a region of a sample and generate a non-linear response in a spatial region smaller than that associated with a Gaussian beam having a width comparable to the width of the embedded Gaussian beam. In another aspect, the light delivery system illuminates a region of a sample and generates a non-linear emission of radiation, is depicted. A further aspect of this embodiment includes an imaging assembly for detecting the non-linear emission and using a signal derived from the detected emission to generate a microscopic image of the sample.

Abstract: A method and apparatus for receiving a digital signal having a plurality of significant bits of resolution. The apparatus includes a mode locked laser comprising a single output. The apparatus also includes a beam divider operable to receive the single output. The apparatus also includes a plurality of optical modulators operable to communicate with said beam divider and operable to receive a respective plurality of signals corresponding to a plurality of significant bits of resolution. Optionally, the apparatus also includes a source operable to output a digital waveform with the plurality of signals corresponding to the plurality of significant bits of resolution of the digital waveform, the plurality of signals operable to drive the plurality of optical modulators.

Abstract: A device for generating or receiving electromagnetic radiation in a frequency range from 10 GHz to 100 THz is provided. The device includes a housing and a wave guide fiber leading into the housing. The wave guide fiber is adapted for guiding pulsed laser light with a first central wavelength. Within the housing, a terahertz converter is provided for generating or receiving the electromagnetic radiation in the terahertz range. The device also includes a frequency converter for converting the light exiting from the wave guide fiber to a second central wavelength being arranged between the end of the wave guide fiber and the terahertz converter in such a way that the terahertz converter is impinged by the frequency converted light.

Abstract: The invention relates to an optical converter system for LEDs, preferably for so-called (W)LEDs, and a method for producing the named optical converter system. The modular-type optical converter system comprises an inorganic converter for converting the radiation emitted from the LED, an inorganic optical component, preferably comprising glass, which is disposed downstream relative to the converter in the direction of emission of the LED, wherein the converter and the first optical component are adjacent to one another and joined at least in sections. The optical converter system possesses a temperature resistance, which lies above that of the system known in the prior art. Also, the preferred components of the system are substantially resistant to UV and to chemicals.

Abstract: A method and apparatus for generating and transmitting high energy optical pulses are described. Distributed temperature sensors usually use Raman scattering in optical fibers as the means to determine the temperature. Here, light from a laser source is sent down a fiber and the small amount of light that is scattered back towards the source is analysed. As the fiber length increases, the resolutions of the temperature and loss measurements become poorer. This is because losses in an optical fiber attenuate the signal. An obvious solution to this problem is to launch more light into the fiber to compensate for the losses but stimulated Raman scattering limits how much light may be launched. The present invention solves this problem by using a pulse conversion method to maximize the resultant pulse energy while the power is kept below SRS threshold.

Abstract: An optical wavelength conversion element includes: a wavelength conversion waveguide that has a periodic polarization reversal structure having alternately and cyclically formed domains of which polarization directions are inverted, that guides light as a fundamental wave corresponding to the periodic polarization reversal structure, and performs a wavelength conversion of the guided fundamental wave; a first clad that is made of a dielectric having a refractive index lower than that of the wavelength conversion waveguide and is provided in contact with the domains; a second clad that is made of a dielectric having a refractive index lower than that of the wavelength conversion waveguide and is provided in contact with the domains such that the second clad is opposed to the first clad film; a first conducting unit that electrically connects the domains in parallel via the first clad; and a second conducting unit that electrically connects the domains in parallel via the second clad.

Abstract: Provided is a terahertz wave apparatus. The terahertz wave apparatus includes: a wavelength-fixed laser emitting a first laser light having a fixed first wavelength; a wavelength-swept laser emitting a second laser light having a tunable second wavelength; a coupler coupling the first laser light with the second laser light; and a generator converting a mixed light emitted from the coupler into a terahertz wave, wherein a frequency of the terahertz wave is continuously tunable.

Abstract: Affords a wavelength converter manufacturing method and a wavelength converter whereby the transmissivity can be improved. A method of manufacturing a wavelength converter (10a) is provided with the following steps. At first, crystal is grown. Then a first crystal (11) and a second crystal (12) are formed by sectioning the crystal into two or more in such a way that the domains are the reverse of each other. The first and second crystals (11) and (12) are then interlocked in such a way that a domain inversion structure in which the polar directions of the first and second crystals (11) and (12) periodically reverse along an optical waveguide (13) is formed, and the domain inversion structure satisfies quasi-phase-matching conditions for an incoming beam (101).

Abstract: It is an object of the present invention to provide an apparatus that can obtain a multiplied harmonic signal fast and with ease, and the method using the apparatus. The object is attained by the method for obtaining a multiple harmonic signal comprises, suppressing a different parity optical signal having parity different from fundamental optical signals; suppressing residual optical signals using an optical filter after suppressing the different parity optical signal; and obtaining the frequency difference component using the fundamental optical signals, and the device realizing the method.

Abstract: A wavelength conversion unit includes a wavelength conversion member that transmits a part of incident excitation light and converts a part of the excitation light into wavelength-converted light having a wavelength different from a wavelength of the excitation light to emit the wavelength-converted light. The excitation light has an intensity distribution in which an intensity is maximum at the center and decreases as getting apart from the center. A thickness of the wavelength conversion member at a portion into which light at the center of the intensity distribution of the excitation light enters is larger than those at any other portions.

Abstract: The invention relates to a frequency changing device comprising a laser having a waveguide and a nonlinear optical medium which changes the frequency of the light generated by the laser. It is provided that the waveguide of the laser at least adjacent to the exit facet of the laser runs at an angle with respect to the perpendicular to the exit facet, that the exit facet of the laser and the entrance facet of the nonlinear optical medium are arranged parallel to one another, and that the exit facet of the laser and the entrance facet of the nonlinear optical medium are oriented with respect to one another in such a way that the condition of Snell's law is met, i.e., nlaser sin(?laser)=nnonlinear optical medium sin(?nonlinear optical medium).

Abstract: The present invention relates to a light source apparatus that has a base structure capable of generating SC light and further having a structure that enables the shaping of the spectral waveform of the SC light, power adjustment of the SC light, or adjustment of the frequency of repetition of the pulse train that contains the SC light. For example, a light source apparatus that enables shaping of spectral waveforms comprises a seed light source that emits seed light which is a pulse train or continuous light; an optical fiber that generates SC light from the seed light, and spectrum shaping means for completely or partially changing the spectral waveform of the SC light. The shaping of the spectral waveform changes the maximum power of the seed light by changing the optical coupling efficiency of the seed light source and optical fiber, for example, thereby suitably deforms the spectrum of the SC light.