Abstract: An optical apparatus, comprising a semiconductor substrate, a dielectric layer located on the semiconductor substrate, wherein a membrane portion of the dielectric layer is located over a cavity in a surface of the semiconductor substrate, a resistive heater located on the membrane portion, the resistive heater being controllable by a current applied to the resistive heater and an etalon optical filter located on the resistive heater and over the cavity, an optical passband of the etalon optical filter being wavelength tunable by the resistive heater. A method of manufacturing the optical apparatus is also disclosed.

Abstract: A vacuum fluctuation quantum random number generator chip includes a heat sink substrate, a laser fixed to a first end of the heat sink substrate, at least two photoelectric detectors fixed to a second end of the heat sink substrate, and a beam splitter fixed to the heat sink substrate and located between the laser and the at least two photoelectric detectors. Light of the laser propagates through the beam splitter. The at least two photoelectric detectors are respectively positioned at optical path outlets of the beam splitter.

Abstract: A system includes at least one controller configured to determine an optical phase modulation pattern for suppression of stimulated Brillouin scattering (SBS) in a combined beam that emerges off a diffractive grating in a spectral beam combining (SBC) system and maximization of an output power of the combined beam. The system also includes multiple master oscillators configured to generate multiple beams in the SBC system. The system also includes multiple phase modulators configured to phase modulate the multiple beams according to the determined optical phase modulation pattern. The system also includes multiple fiber amplifier chains configured to receive the phase modulated beams and output the beams from the master oscillators to multiple delivery fibers for subsequent combining into the combined beam at the diffractive grating.

Abstract: A distributed reflector (DR) laser may include a distributed feedback (DFB) region and a distributed Bragg reflector (DBR). The DFB region may have a length in a range from 30 micrometers (?m) to 100 ?m and may include a DFB grating with a first kappa in a range from 100 cm?1 to 150 cm?1. The DBR region may be coupled end to end with the DFB region and may have a length in a range from 30-300 ?m. The DBR region may include a DBR grating with a second kappa in a range from 150 cm?1 to 200 cm?1. The DR laser may additionally include a lasing mode and a p-p resonance frequency. The lasing mode may be at a long wavelength side of a peak of a DBR reflection profile of the DBR region. The p-p resonance frequency may be less than or equal to 70 GHz.

Abstract: Provided is an apparatus for acquiring object information, the apparatus including: first and second laser output unit outputting first and second pulsed laser; a laser controlling unit configured to control each laser output unit; a first or second detecting unit configured to detect an emission timing of laser and output a first or second detection signal; a probe configured to receive an acoustic wave from an object being irradiated with the laser; and a signal processing unit configured to acquire specific information of the object, based on the acoustic wave. The laser controlling unit controls output of at least one of the laser output units so as to decrease a time difference between subsequent first and second pulsed lasers to be output.

Abstract: A distributed reflector (DR) laser may include a distributed feedback (DFB) region and a distributed Bragg reflector (DBR). The DFB region may have a length in a range from 30 micrometers (?m) to 100 ?m and may include a DFB grating with a first kappa in a range from 100 cm?1 to 150 cm?1. The DBR region may be coupled end to end with the DFB region and may have a length in a range from 30-300 ?m. The DBR region may include a DBR grating with a second kappa in a range from 150 cm?1 to 200 cm?1. The DR laser may additionally include a lasing mode and a p-p resonance frequency. The lasing mode may be at a long wavelength side of a peak of a DBR reflection profile of the DBR region. The p-p resonance frequency may be less than or equal to 70 GHz.

Abstract: A nanosecond pulser is disclosed. In some embodiments, the nanosecond pulser may include one or more switch circuits including one or more solid state switches, a transformer, and an output. In some embodiments, the transformer may include a first transformer core, a first primary winding wound at least partially around a portion of the first transformer core, and a secondary winding wound at least partially around a portion of the first transformer core. In some embodiments, each of the one or more switch circuits are coupled with at least a portion of the first primary winding. In some embodiments, the output may be electrically coupled with the secondary winding and outputs electrical pulses having a peak voltage greater than about 1 kilovolt and a rise time of less than 150 nanoseconds or less than 50 nanoseconds.

Abstract: A light-emitting diode is provided. The light-emitting diode includes a first semiconductor structure having an upper surface and a lower surface; a second semiconductor layer disposed adjacent to the upper surface; a third semiconductor layer disposed adjacent to the lower surface; two light-emitting layers disposed between the upper surface and the second semiconductor layer and disposed between the lower surface and the third semiconductor layer, respectively; a first electrode disposed over the second semiconductor layer; and a second electrode disposed over the third semiconductor layer.

Abstract: The present invention provides a burst-laser generator using an optical resonator which produces high pulse-strength of burst-laser in order to conduct laser Compton scattering, comprising: a self-oscillation amplifying optical loop-path and an external optical resonator to burst-amplify laser, wherein, laser supplied by an exciting laser source is self-oscillation amplified with the self-oscillation amplifying optical loop-path and further burst-amplified with the external optical resonator.

Abstract: A quantum interference device includes: gaseous alkali metal atoms; and a light source for causing a resonant light pair having different frequencies that keep a frequency difference equivalent to an energy difference between two ground states of the alkali metal atoms, the quantum interference device causing the alkali metal atoms and the resonant light pair to interact each other to cause an electromagnetically induced transparency phenomenon (EIT), wherein there are a plurality of the resonant light pairs, and center frequencies of the respective resonant light pairs are different from one another.

Abstract: The present invention uses a laser apparatus capable of selecting a wavelength of light to be outputted from a plurality of wavelengths, including: a branching unit which is formed of a polarizer and is configured to branch an optical path formed in a resonator including a reflecting unit having a plurality of fixed reflecting planes and an output mirror, into a plurality of optical paths, thereby forming a common optical path having an end defined by the output mirror and a plurality of optical path branches each having an end defined by any one of the reflecting planes; a laser medium disposed in the common optical path; and a selecting unit configured to select, from the plurality of optical path branches, an optical path branch which corresponds to a wavelength of light to be outputted.

Abstract: A method to tune an emission wavelength of a laser diode (LD) finely is disclosed. The method first controls a temperature of the etalon filter in T1 or T2, where the transmittance of the etalon filter becomes 40 to 50%, assuming a height between the peak and the bottom of the periodic transmittance to be 100%, at the grid wavelength ?1 or ?2, respectively. Then, the temperature of the LD is adjusted such that the intensity of light emitted from the LD and transmitted through the etalon filter becomes 40 to 50%.

Abstract: A terahertz light generation device 1 comprises a resonator structure 12 for intensifying incident light and outputting the intensified light and laser oscillation units 10, 11 for feeding the incident light into the resonator structure 12. The incident light comprises first and second incident light components having polarization states different from each other and frequencies different from each other. The laser oscillation units 10, 11 feed the resonator structure 12 with the first and second incident light components at an angle inclined from a principal surface in the resonator structure 12. The resonator structure 12 outputs light having a frequency corresponding to the difference between the respective frequencies of the first and second incident light components.

Abstract: A method for generation of electromagnetic radiation has the following method steps: generation of electromagnetic radiation at a useful frequency, division of the electromagnetic radiation into a useful beam and a secondary beam, frequency shift of the electromagnetic radiation of the secondary beam, control of the useful frequency as determined by a manipulated variable, wherein the manipulated variable is derived from the frequency-shifted radiation of the secondary beam.

Abstract: A microlaser system includes an optical source, a microlaser, an actuator switch, and a photovoltaic power source. The microlaser, which includes a control element, is optically pumped by at least a portion of light emitted by the optical source. The actuator switch is configured to be activated by a triggering event. Furthermore, the photovoltaic power source is coupled in a series connection with the actuator switch and the control element, the series connection configured to connect the photovoltaic power source to the control element of the microlaser when the actuator switch is activated by the triggering event.

Abstract: A circuit is provided for generating a modulated laser diode control signal from a laser diode control signal, the circuit having an RF modulator for modulating the laser diode control signal with a modulation signal; the circuit having adjustment means for adjusting the RF modulator; the adjustment means being configured or configurable as a function of at least one laser diode operating information item. Furthermore, a laser diode receptacle is described as having such a circuit, a projector, particularly an image projector having such a laser diode receptacle, an image projector having such a laser diode receptacle and a laser diode, as well as a method for adjusting an RF modulator of such a circuit and a method for producing such a laser diode receptacle.

Abstract: The invention concerns an oscillator generating a wave composed of a frequency of on the order of terahertz from a beat of two optical waves generated by a dual-frequency optical source. The oscillator includes a modulator the transfer function of which is non-linear for generating harmonics with a frequency of less than one terahertz for each of the optical waves generated by the dual-frequency optical source, an optical detector able to detect at least one harmonic for each of the optical waves generated by the dual-frequency optical source and transforming the harmonics detected into an electrical signal, a phase comparator for comparing the electrical signal with a reference electrical signal, and a module for controlling at least one element of the dual-frequency optical source with a signal obtained from the signal resulting from the comparison.

Abstract: An OPO is disclosed capable of rapid frequency tuning by non-mechanical means. The OPO includes a resonant cavity including one or more non-linear crystals in an optical path thereof. A pump laser pulse is transmitted into the resonant cavity simultaneously with a seed beam having a desired wavelength. The output beam from the resonant cavity has the same center wavelength as the seed beam. The wavelength of the seed beam may be modulated at a frequency larger than the pulse rate of the pump laser or larger than the inverse of the pulse duration. The OPO disclosed may be used to perform DIAL analysis wherein intra-pulse modulation of an output beam is used to obtain measurements of absorption at multiple frequencies for each pulse of a pump beam.

Abstract: Opto-electronic oscillator (OEO) devices include an optical resonator filter to block the strong laser light at the laser carrier frequency from entering the optical resonator filter and to select one of the weak modulation sidebands, which is in resonance with the optical resonator filter, to be coupled into the optical resonator filter. The laser light at the laser carrier frequency and other modulation sidebands bypass the optical resonator filter to reach a fast photodetector. The laser light in the selected modulation sideband in the optical resonator filter is then coupled out to mix with the laser light at the laser carrier frequency and other modulation sidebands at the fast photodetector to produce the detector output as the input to the electrical part of the opto-electronic loop to produce the OEO oscillation.

Abstract: In the field of the production of very high frequencies, for example from 1 gigahertz to several terahertz, by beating the frequencies of two laser beams together, a device includes a resonant optical cavity having very stable dimensions receiving the beams, with for each beam, an interrogation device of the resonant cavity supplying an electrical signal representing the difference in frequency between the light frequency of the beam and a resonance frequency of the resonant cavity. The frequency of each beam is servo controlled to minimize the frequency difference observed. The laser beams are produced by a dual-frequency laser producing two beams of different frequencies and orthogonal polarizations. A polarization separator is used for separate servo control of the beams according to polarization, and a polarizer is placed behind a main output of the resonant cavity producing an electromagnetic beam mixing the two polarizations and amplitude-modulated at the beat frequency.

Abstract: One embodiment is directed towards a stabilized laser including a laser to produce light at a frequency and a resonator coupled to the laser such that the light from the laser circulates therethrough. The laser also includes Pound-Drever-Hall (PDH) feedback electronics configured to adjust the frequency of the light from the laser to reduce phase noise in response to light sensed at the reflection port of the resonator and transmission port feedback electronics configured to adjust the frequency of the light from the laser toward resonance of the resonator at the transmission port in response to the light sensed at the transmission port of the resonator, wherein the transmission port feedback electronics adjust the frequency at a rate at least ten times slower than the PDH feedback electronics.

Abstract: Laser emission device with integrated light modulator comprising: a multilayer waveguide comprising, on a support layer, a first guiding layer, a first doped layer, a second guiding layer of light amplifying material, and a biasing second doped layer opposite the first doped layer, the waveguide comprising a laser amplification section (50), a light modulation section (52) comprising an extraction zone for radiating the light, a transition section (51) inserted between the laser amplification section and the light modulation section, a positive first electrode for injecting a pumping current into the laser amplification section, a positive second electrode for injecting a modulation signal into the modulation section, a negative third electrode, and a reference fourth electrode, the second doped layer comprising an electrical insulation situated in the transition section to form a resistive channel.

Abstract: A method for generation of electromagnetic radiation has the following method steps: generation of electromagnetic radiation at a useful frequency, division of the electromagnetic radiation into a useful beam and a secondary beam, frequency shift of the electromagnetic radiation of the secondary beam, control of the useful frequency as determined by a manipulated variable, wherein the manipulated variable is derived from the frequency-shifted radiation of the secondary beam.

Abstract: A system and method for controllably chirping electromagnetic radiation from a radiation source includes an optical cavity arrangement. The optical cavity arrangement enables electromagnetic radiation to be produced with a substantially linear chirp rate and a configurable period. By selectively injecting electromagnetic radiation into the optical cavity, the electromagnetic radiation may be produced with a single resonant mode that is frequency shifted at the substantially linear chirp rate. Producing the electromagnetic radiation with a single resonant mode may increase the coherence length of the electromagnetic radiation, which may be advantageous when the electromagnetic radiation is implemented in various applications. For example, the electromagnetic radiation produced by the optical cavity arrangement may enhance a range, speed, accuracy, and/or other aspects of a laser radar system.

Abstract: The present disclosure describes semiconductor external cavity laser with wide bandwidth frequency modulation capabilities. The laser is preferably packaged in a standard form-factor package, such as a 14-pin butterfly package. The front end of the cavity comprises an integrated planar circuit (e.g., silica-on-silicon planar lightwave circuit with Bragg gratings), and the “back facet” of the laser is implemented as a high-reflection (HR) coated LiNbO3 phase tuning section in the double pass configuration. AC-voltage signal applied to the electrodes of phase tuning section modulates a refractive index of the propagating TE-polarization mode of external cavity and produces frequency modulation. Such frequency modulation is not associated with any thermal behavior of the gain element included in the external cavity laser, and has a negligible phase delay over a wide bandwidth.

Abstract: Embodiments of the present invention use an external cavity laser source with dual input terminals, such as bias current for a gain section, and a voltage signal for a modulator section. An aspect of the present invention provides an ultra-low frequency noise external cavity frequency modulated (FM) semiconductor laser source frequency stabilized by a dual electronic feedback circuitry applied to semiconductor gain section and a modulation section. A further aspect of the present invention provides an optical frequency discriminator based on homodyne phase demodulation using an unbalanced Michelson interferometer with fiber optics delay and a symmetrical 3×3 optical coupler.

Abstract: Disclosed are systems and methods to extract information about the size and shape of an object by observing variations of the radiation pattern caused by illuminating the object with coherent radiation sources and changing the wavelengths of the source. Sensing and image-reconstruction systems and methods are described for recovering the image of an object utilizing projected and transparent reference points and radiation sources such as tunable lasers. Sensing and image-reconstruction systems and methods are also described for rapid sensing of such radiation patterns. A computational system and method is also described for sensing and reconstructing the image from its autocorrelation. This computational approach uses the fact that the autocorrelation is the weighted sum of shifted copies of an image, where the shifts are obtained by sequentially placing each individual scattering cell of the object at the origin of the autocorrelation space.

Abstract: Signal generating systems and methods are described. One signal generation system includes first and second lasers configured to generate first and second laser beams having respective frequencies wherein a difference in the respective frequencies corresponds to an output frequency, a photodetector configured to produce a signal at the output frequency, and first and second electro-optic modulators configured to respectively electro-optically modulate the first and second laser beams using the signal to produce respective first and second modulated optical signals, each of the first and second modulated optical signals having a respective sideband corresponding to the frequency of the other one of the first and second laser beams. The first laser is seeded with the respective sideband of the second modulated optical signal and the second laser is seeded with the respective sideband of the first modulated optical signal to phase-lock the first and second laser beams to each other.

Abstract: An RF power-supply for driving a carbon dioxide CO2 gas-discharge laser includes a plurality of power-oscillators phase-locked to a common reference oscillator. Outputs of the phase-locked power-oscillators are combined by a power combiner for delivery, via an impedance matching network, to discharge-electrodes of the laser. In one example the powers are analog power-oscillators. In another example, the power-oscillators are digital power-oscillators.

Abstract: An Optical Parametric Oscillator (OPO) capable of rapid or broadband frequency tuning by non-mechanical or mechanical means includes a resonant cavity with one or more non-linear crystals in an optical path thereof. The non-linear crystals may be driven by actuators. A pump laser pulse is transmitted into the resonant cavity with one or more seed beams having a desired wavelength. The output beam from the resonant cavity may have the same center wavelength as the one or more seed beams which may be modulated at a frequency larger than that of the pump laser, or the inverse of the pulse duration. The OPO may be used in Light Detection And Ranging (LIDAR) or Differential Absorption LIDAR (DIAL) analysis by intra-pulse modulation of output to measure absorption at multiple frequencies for each pulse of a pump beam. Sum Frequency Generator configurations may be suitable for narrow and broadband UV generation.

Abstract: A high-efficiency laser diode is provided. Since a ?/4 phase-shifted distributed feedback (DFB) laser diode has a great coupling coefficient, mode stability is poor due to spatial hole burning when multiplication of the coupling coefficient by length of a resonator is equal to or greater than 2. In the inventive concept, a region capable of controlling spatial hole burning is inserted into a semiconductor laser diode structure. Thus, an ultrahigh-speed pulse laser diode having a repetition rate in the band ranging from 100 GHz to 300 GHz is obtained. In addition, a single-mode laser diode with improved energy use efficiency is implemented by changing the configuration of a laser diode.

Abstract: The present invention relates to method for spectrally equalized frequency comb generation. In order to carry this method, the following steps are followed: seed laser or lasers are modulated to acquire frequency chirp necessary to enable temporal compression and an increase in peak optical intensity necessary for an efficient nonlinear optical mixing process to occur; the compressed waveform is reshaped by nonlinear-transfer optical element and subsequently used to generate frequency comb in nonlinear waveguide. Ultimately, at the conclusion of these steps, a frequency comb is generated with substantially flat optical spectrum, while retaining variability with respect to the frequency pitch, high coherency and substantially wide spectral band of coverage.

Abstract: A tunable laser, including: a laser resonant cavity; a laser gain medium; an intra-cavity collimating lens; an acousto-optic tunable filter; a device exciting sound waves in an acousto-optic crystal; a radio frequency signal source providing radio frequency energy for the energy transducer and adjusting the oscillation wavelength of the laser resonant cavity by changing radio signal frequency; an optical phase modulator disposed between the intra-cavity collimating lens and the acousto-optic crystal; an optical etalon disposed between the optical phase modulator and the laser gain medium; a wavelength locker disposed at one of zero-order diffraction optical paths of intra-cavity light; a pigtailed collimator coupling laser output light to an optical fiber; a pumping source exciting the laser gain medium; a phase modulator driver for driving the optical phase modulator; and a signal control processing circuit.

Abstract: The invention relates to vertical cavity lasers (VCL) incorporating a reflectivity-modulated grating mirror (1) for modulating the laser output. A cavity is formed by a bottom mirror (4), an active region (3), and an outcoupling top grating mirror (1) formed by a periodic refractive index grating region in a layer structure comprising a p- and a n-doped semiconductor layer with an electrooptic material layer (12) arranged there between. The grating region comprises a grating structure formed by periodic perforations to change the refractive index periodically in directions normal to the oscillation axis. A modulated voltage (91) is applied in reverse bias between the n- and p-doped layers to modulate the refractive index of the electrooptic material layer (12) and thereby the reflectivity spectrum of the grating mirror (1).

Abstract: Compact optical frequency sources are described. The comb source may include an intra-cavity optical element having a multi-material integrated structure with an electrically controllable active region. The active region may comprise a thin film. By way of example, the thin film and an insulating dielectric material disposed between two electrodes can provide for rapid loss modulation. In some embodiments the thin film may comprise graphene. In various embodiments of a frequency comb laser, rapid modulation of the CEO frequency can be implemented via electric modulation of the transmission or reflection loss of an additional optical element, which can be the saturable absorber itself. In another embodiment, the thin film can also be used as a saturable absorber in order to facilitate passive modelocking. In some implementations the optical element may be formed on a cleaved or polished end of an optical fiber.

Abstract: This invention relates to opto-electronic systems using semiconductor lasers driven by optical phase-locked loops that control the laser's optical phase and frequency. Feedback control provides a means for precise, wideband control of optical frequency and phase, augmented further by four wave mixing stages and digitally stitched independent optical waveforms for enhanced tunability.

Abstract: Method for calibrating and tuning a part wise monotonically, continuously tunable semiconductor laser having a phase section and a first Bragg reflector section, through which sections a phase current and a first reflector current, respectively, are applied, which laser is not actively cooled, includes a) a calibration step, including obtaining at least two tuning lines along which tuning lines all combinations of phase and Bragg currents are stable operating points, identifying at least one reference stable operating point along a first one of the identified tuning lines at which operating point the laser emits light at a certain reference frequency, and storing at least one reference stable operating point; and b) a subsequent tuning step, during which the output frequency of the laser in relation to the reference frequency is controlled to a desired output frequency by translating the operating point of the laser along the first tuning line.

Abstract: An ultraviolet laser device equips a laser beam output unit that includes first, second and third amplifiers that output first through third infrared laser beams, and first through third optical systems into which the first through third infrared laser beams through which the first through third infrared laser beams are propagated. A wavelength conversion unit includes a fourth optical system into which the combined first through third laser beams are incident through which they are propagated. The first optical system wavelength converts and generates the first infrared laser beam to a predetermined harmonic wave as the first laser beam, the fourth optical system includes a first wavelength conversion element that generates an earlier stage ultraviolet laser beam between the predetermined harmonic wave and the second laser beam, and the second wavelength conversion element generates an ultraviolet laser beam between the earlier stage ultraviolet laser beam and the third laser beam.

Abstract: A light source device is provided with a coherent light source for emitting the coherent light, and a pattern changer for changing an interference pattern of the coherent light on a surface of the illumination object. The pattern changer includes a photorefractive crystal which is arranged between the coherent light source and the illumination object and on an optical path of the coherent light and exhibits a photorefractive effect, and a changer for changing at least one of a light intensity distribution, a polarization direction, a wavelength and an intensity of coherent light incident on the photorefractive crystal. The illumination object is illuminated with the coherent light.

Abstract: Various exemplary embodiments relate to an optical isolator in an integrated optical circuit including: a first optical modulator configured to provide a first periodic phase modulation on an input optical signal; a second optical modulator configured to provide a second periodic phase modulation on the modulated optical signal; and an optical waveguide having a length L connecting the first optical modulator to the second optical modulator; wherein the phase difference between the first and second periodic phase modulation is ?/2, and wherein the length L of the optical waveguide causes a phase delay of ?/2 on an optical signal traversing the optical waveguide.

Abstract: The invention relates to a method for generating coherent-phase light having a predefinable frequency value (?Soll), comprising the steps of generating working light with a working frequency (?SL), generating a frequency comb (10), which is a light field that consists of equidistant coherent-phase spectral lines, selecting a comb line (having the index m) from the frequency comb (10) having a frequency (?m), generating a frequency shift (??) of the frequency comb (10) and/or the working frequency (?SL) by means of time-dependent phase settings (?S(t)) modulo a multiple of 2?, in particular of 2?, and phase-coupling the possibly frequency-shifted fields of the working light (?SL) and the one possibly frequency-shifted frequency comb line (?m), so that the frequencies thereof are rigidly phase-coupled via the frequency shift (??), and working light having the desired frequency (?Soll) is obtained.

Abstract: A device and a method enabling the enhancing of the modulation efficiency of lasers by matching the modulation frequency and the FSR of the laser. This is optionally achieved by eliminating the internal cavity of a laser diode (103) placed in an external cavity and matching the FSR of the external cavity to the modulation frequency. The modulation index is enhanced to and beyond the point of complete carrier suppression even at high modulation frequency and high beam intensities. The external cavity comprises a grating (107), the cavity length being adjusted with a PZT (108) and a translation stage (109). The laser diode (103) is driven by a bias current (110) from a driver (115) and a modulation current (111) from a modulation driver (116).

Abstract: The invention relates to a precision optical frequency tunable laser. The laser includes: a laser gain medium, an intracavity collimating lens, an active optical phase modulator, a tunable acousto-optic filter and an intracavity total reflection mirror all arranged sequentially in a laser cavity, and the tunable laser further includes an active polarization rotator, a polarization beam splitter, two etalons, a temperature control system attached to the etalons, two total reflection mirrors, a radio frequency signal source, a laser pumping source, an active optical phase modulator drive source, an active polarization rotator drive source and a laser drive control circuit. Through the temperature control system attached to the etalons, stable laser output and the precision optical frequency tuning less than 1 GHz within a wide spectrum range can be realized, thereby greatly reducing the bandwidth requirements in achieving narrowband filtering for the tunable acousto-optic filter.

Abstract: A bias circuit of an electro-absorption modulated laser and a calibration method thereof are provided. The bias circuit includes a drive circuit and a direct current bias voltage circuit. The drive circuit is used for providing a forward bias voltage to a laser diode in the electro-absorption modulated laser to generate laser. The direct current bias voltage circuit is connected to a cathode of an electro-absorption modulator in the electro-absorption modulated laser, and provides a positive direct current bias voltage to the cathode to enable the reverse bias voltage of the electro-absorption modulator to fall within the range of modulation. When the reverse bias voltage falls within the range of modulation, the electro-absorption modulator utilizes the laser generated by the laser diode as optical carrier wave, modulates the optical carrier wave with the modulation voltage, and outputs a modulated optical signal.

Abstract: The invention relates to a method for generating coherent-phase light having a predefinable frequency value (?Soll), comprising the steps of generating working light with a working frequency (?SL), generating a frequency comb (10), which is a light field that consists of equidistant coherent-phase spectral lines, selecting a comb line (having the index m) from the frequency comb (10) having a frequency (?m), generating a frequency shift (??) of the frequency comb (10) and/or the working frequency (?SL) by means of time-dependent phase settings (?S(t)) modulo a multiple of 2?, in particular of 2?, and phase-coupling the possibly frequency-shifted fields of the working light (?SL) and the one possibly frequency-shifted frequency comb line (?m), so that the frequencies thereof are rigidly phase-coupled via the frequency shift (??), and working light having the desired frequency (?Soll) is obtained.

Abstract: A light source apparatus includes an optical resonator formed by an optical amplification medium and an optical switch. The optical switch includes a saturable absorber and changes its transmittance or reflectance when receiving an optical pulse emitted from a light irradiation source which includes a wavelength-tunable light source. The light source apparatus emits amplified light from the optical resonator in correspondence with the center wavelength of the optical pulse from the wavelength-tunable light source. The relationship between a length L and an effective refractive index n of the optical resonator and a repetition frequency f of the optical pulse satisfies a condition L<c/(nf), and a relationship between the length L and a recovery time ? in which the changed transmittance or reflectance of the optical switch recovers satisfies a condition ?>(nL)/c.

Abstract: A wavelength-tunable light source apparatus includes a first light source apparatus and a second light source apparatus. The first light source apparatus is capable of changing an oscillation wavelength and includes a resonator. The resonator includes an optical amplification medium for amplifying light and a waveguide having wavelength distribution. The second light source apparatus is connected to the waveguide and configured to introduce pulsed light as modulation light to the first light source apparatus. The oscillation wavelength is controlled by active mode locking employing cross-gain modulation using the modulation light. The pulse width of the modulation light has a duration shorter than a duration of a half period of a driving signal for generating the modulation light.

Abstract: A low white frequency noise tunable semiconductor laser source is presented. The laser source includes a single-mode semiconductor laser assembly which generates a laser beam having a tunable frequency over a spectral range of interest. An optical filter is provided in the path of the laser beam. The optical filter has multiple spectral features distributed over the entire spectral range of interest. Each spectral feature has a narrow spectral range. A locking mechanism is further provided and is controllable for locking a spectral alignment between the frequency of the laser beam and any selected one of the spectral features of the optical filter.

Abstract: An optoelectronic swept-frequency semiconductor laser coupled to a microfabricated optical biomolecular sensor with integrated resonator and waveguide and methods related thereto are described. Biomolecular sensors with optical resonator microfabricated with integrated waveguide operation can be in a microfluidic flow cell.

Abstract: Signal generating systems and methods are described. One signal generation system includes first and second lasers configured to generate first and second laser beams having respective frequencies wherein a difference in the respective frequencies corresponds to an output frequency, a photodetector configured to produce a signal at the output frequency, and first and second electro-optic modulators configured to respectively electro-optically modulate the first and second laser beams using the signal to produce respective first and second modulated optical signals, each of the first and second modulated optical signals having a respective sideband corresponding to the frequency of the other one of the first and second laser beams. The first laser is seeded with the respective sideband of the second modulated optical signal and the second laser is seeded with the respective sideband of the first modulated optical signal to phase-lock the first and second laser beams to each other.