Abstract: A semiconductor light emitting device includes a microstrip substrate with a single-ended transmission line on a top surface, wherein the single-ended transmission line extends from a first end portion to a second end portion, the microstrip substrate has a ground plane on a bottom surface, and the ground plane is opposed and bonded to the conductive pattern. The single-ended transmission line includes a first section and a second section, wherein the second section extends from the first section and includes the second end portion. The second section is lower in characteristic impedance than the first section. A load circuit that includes the wire, the optical modulator, and the termination resistor is electrically connected between the second end portion and the conductive pattern. The load circuit is equal to or lower in the characteristic impedance than the second section.

Abstract: An image reading apparatus includes a cover, a reading device including a light source and a sensor, and a control device including circuitry. The circuitry acquires first data with the light source turned off, acquires second data with the light source turned on, calculates a first evaluation value for each of plural locations of the first data, calculates a second evaluation value for each of plural locations of the second data, determines an open or closed state of the cover based on the first evaluation value and the second evaluation value, determines that the cover is open when at least one of a determination result based on the first evaluation value or a determination result based on the second evaluation value indicates the open state of the cover, and determines that the cover is closed when the two determination results both indicate the closed state of the cover.

Abstract: A method for adjusting a laser beam includes, following passage of the laser beam through a beam-shaping device, measuring, via a detector of a detector device, a beam profile of the laser beam. The method further includes determining a beam quality property of the laser beam based on the measured beam profile and altering an adjustable optical unit for modifying at least one property of the laser beam prior to the entry into the beam-shaping device. For adjusting the laser beam, the adjustable optical unit is altered based on the determined beam quality property.

Abstract: The present invention is intended to reduce variations in oscillation wavenumber of a semiconductor laser element due to the influence of circumferential temperatures. The invention includes a semiconductor laser semiconductor laser element, a temperature control part to control a temperature of the semiconductor laser element, a temperature sensor to detect a temperature of the temperature control part, and a temperature control device to control a supply signal to the temperature control part so that a detected temperature obtained from the temperature sensor reaches a predetermined target temperature. The temperature control device changes a target temperature for the temperature control part depending on a supply signal to the temperature control part.

Abstract: A control system includes a field-programmable gate array (FPGA), a digital-to-analog conversion (DAC) circuit, an external TEC driver, and a pump chip. The field-programmable gate array (FPGA) includes a pump driver and a thermoelectric-cooler (TEC) controller. The digital-to-analog conversion (DAC) circuit is coupled to the FPGA. The external TEC driver is external to the FPGA and coupled to the FPGA. The pump chip includes a pump and a TEC and is coupled to the DAC circuit and the external TEC driver.

Abstract: Provided is a thermoelectric cooler built-in stem, including a first stem member on a top face of which a temperature controlled target device such as an optical module or the like is mounted, a second stem member which opposes to the first stem member each other, and a thermoelectric cooler being sandwiched between the first stem member and the second stem member, for controlling the temperature controlled target device, whereby a space between the first stem member and the second stem member is filled by an insulating resin whose thermal conductivity is low.

Abstract: The present invention is the sub-carrier modulated terahertz radar that modulates a main-carrier signal in the terahertz frequency band, which is generated from a resonant tunneling diode (RTD), by a sub-carrier signal in a gigahertz frequency band whose frequency varies periodically, irradiates a frequency-modulated irradiation light to a target, detects and demodulates a reflected light from the target, mixes a demodulated signal with the sub-carrier signal, performs a Fourier transform on a mixed signal, and measures a distance from an irradiation position to the target by using a Fourier-transformed frequency signal.

Abstract: Described herein are methods for developing and maintaining pulses that are produced from compact resonant cavities using one or more Q-switches and maintaining the output parameters of these pulses created during repetitive pulsed operation. The deterministic control of the evolution of a Q-switched laser pulse is complicated due to dynamic laser cavity feedback effects and unpredictable environmental inputs. Laser pulse shape control in a compact laser cavity (e.g., length/speed of light <˜1 ns) is especially difficult because closed loop control becomes impossible due to causality. Because various issues cause laser output of these compact resonator cavities to drift over time, described herein are further methods for automatically maintaining those output parameters.

Abstract: An optical subassembly includes an eyelet including a first through-hole penetrating from a first surface through a second surface; a first lead terminal, which is to be inserted into the first through-hole, and is configured to transmit an electric signal; a dielectric material, which is filled in a space between the first through-hole and the first lead terminal; a device mounting substrate, on which an optical device is to be mounted, and which includes a first conductor pattern configured to transmit the electric signal to the optical device; a metal block having mounted thereon the device mounting substrate; a temperature regulator placed between the metal block and the eyelet; a relay substrate including a second conductor pattern, which is configured to transmit the electric signal to the optical device; a seat, which protrudes from the first surface in a direction extended from the first through-hole, and has a third surface mounting the relay substrate; and a spacer interposed between the third surfa

Abstract: An arrangement monitors an optical element. The arrangement includes: a light source configured to emit radiation onto a surface of the optical element; a detector configured to detect the radiation that has been at least partially reflected at the surface of the optical element; and a holder for the optical element, in which the light source and the detector are integrated. The holder has a cooling region through which a cooling liquid is configured to flow, the cooling region being in contact with the optical element. The holder has a reservoir, through which a beam path between the light source and the detector extends. The reservoir is configured to receive the cooling liquid leaking out at the optical element in case of a leakage.

Abstract: A laser diode module is described herein. In accordance with a first exemplary embodiment, the laser diode module includes a first semiconductor die including at least one electronic switch, and a second semiconductor die including at least one laser diode. The second semiconductor die is bonded on the first semiconductor die using a chip-on-chip connecting technology to provide electrical connection between the electronic switch and the laser diode.

Abstract: Embodiments of the disclosure pertain to an optical transmitter comprising a laser configured to generate an optical signal from a single-ended electrical signal, a housing or (sub)assembly containing the laser, a driver configured to generate the single-ended electrical signal, a direct current (DC) return path, and an alternating current (AC) return path. The laser has a DC power pin, and the DC power has a DC component and an AC component. The driver has a first impedance at a first output through which the single-ended electrical signal passes. The housing or (sub)assembly has a second impedance matching the first impedance. The DC return path comprises an inductor and is configured to carry or conduct the DC component of the DC power from the laser (e.g., to an input pin on the driver). The AC return path is configured to carry or conduct the AC component of the DC power from the laser. Methods of using and manufacturing the same are also disclosed.

Abstract: A semiconductor laser chip-on-carrier (CoC) device comprising: a semiconductor laser component comprising an electric laser terminal; a driver circuit for producing on an electric driver terminal an alternating current electric driving signal; and an electric signal conductor electrically connecting the driver terminal to the laser terminal, wherein the electric signal conductor comprises: a first printed trace which is not arranged on the semiconductor laser component and which comprises a first trace elongated section and a first trace downstream terminal section; and a first wire bond, connecting the first trace downstream terminal section to the laser terminal, and wherein the first trace elongated section is adapted to the semiconductor laser component such that the first trace elongated section and an internal capacitance of the semiconductor is laser component together correspond to an impedance which is at the most 20% from an output impedance of an output terminal of the driver circuit.

Abstract: The present disclosure provides a laser device, where the laser device comprises a substrate, a seed laser disposed on the substrate, and a radiofrequency coil. Two connection ends of the radiofrequency coil are connected with corresponding pin ends of the seed laser, respectively.

Abstract: Driver laser systems for EUV radiation producing apparatuses are disclosed that include a beam source for producing laser radiation propagating in a first direction, an amplifier arrangement comprising at least one optical amplifier for amplifying the laser radiation propagating in the first direction, and at least one optical isolator. The optical isolator includes a chamber filled with a gas, through which chamber the laser radiation propagating in the first direction passes, and a plasma generating device configured for the pulsed ignition of a plasma in the gas of the chamber to suppress passage of laser radiation propagating in a second direction, opposite to the first direction, through the chamber. EUV radiation producing apparatuses that include such driver laser systems are also disclosed.

Abstract: The invention relates to an assembly comprising an electric component. The component has an electric part, a control circuit, and a capacitor. At least two lead frames are provided which are embedded into a housing. The part, the control circuit, and the capacitor are arranged on the lead frames, and the control circuit is designed to charge the capacitor and to supply the part with current from the capacitor in a clocked manner. The component has two contacts, and the component is arranged on a support. The support has an electrically conductive layer and the two contacts are connected to the layer in an electrically conductive manner. At least one first part of one lead frame is arranged at a greater distance from the electrically conductive layer than the second lead frame.

Abstract: Methods, devices and systems are described for enabling a series-connected, single chip vertical-cavity surface-emitting laser (VCSEL) array. In one aspect, the single chip includes one or more non-conductive regions one the conductive layer to produce a plurality of electrically separate conductive regions. Each electrically separate region may have a plurality of VCSEL elements, including an anode region and a cathode region connected in series. The chip is connected to a sub-mount with a metallization pattern, which connects each electrically separate region on the conductive layer in series. In one aspect, the metallization pattern connects the anode region of a first electrically separate region to the cathode region of a second electrically separate region. The metallization pattern may also comprise cuts that maintain electrical separation between the anode and cathode regions on each conductive layer region, and that align with the etched regions.

Abstract: Inductor cooling systems and methods are disclosed. A vehicle inductor cooling system may include an inductor assembly, a flange extending around a periphery of the inductor assembly, and a sealing wall having an outer periphery and a sealing surface forming a seal with the flange. A bottom surface may extend from the outer periphery and a cavity may be defined by the outer periphery, the bottom surface, and the inductor assembly. A coolant inlet may be configured to provide coolant to the cavity. The inductor assembly may include at least one conductive coil wrapped around a core. A bottom portion, optionally only the bottom portion, of the coil may be disposed within the cavity and configured to be directly contacted and cooled by the coolant (e.g., ATF).

Abstract: An optical modulator with FPC and optical transmission device using the same are provided. This optical modulator includes a flexible printed circuit which electrically connects the optical modulator to a circuit board. The flexible printed circuit has a substantially quadrilateral shape. A pad is formed on the flexible printed circuit along one side of the substantially quadrilateral shape so as to be electrically connected to the circuit board. In order to release the mechanical stress applied onto the side or the end portion of the flexible printed circuit and/or to prevent propagation of distortion generated in the side or the end portion, the flexible printed circuit has: a cutout or a notch provided in a direction from a part of at least one side toward the inside of the flexible printed circuit; and/or a curved portion connecting at least two adjacent sides.

Abstract: A laser apparatus includes a light source configured to output excitation light, an optical resonator in which laser medium is excited by the excitation light, the optical resonator being configured to output laser beam, a temperature regulator configured to adjust temperature of the light source to a standard temperature, an optical detector configured to detect output power of the laser beam, and a controller configured to change the standard temperature based on the detected output power of the laser beam.

Abstract: An optical module includes: a wiring substrate that has a wiring pattern including a connecting portion and is arranged on an optical subassembly so as to be electrically connected thereto; and a flexible insulating layer formed between the optical subassembly and the wiring substrate. The optical subassembly includes: a conductive stem that has a surface opposed to the wiring substrate, the conductive stem being shaped so that the surface has a through hole opened therein and being connected to a reference potential; and a signal lead for transmitting a signal, the signal lead passing through the through hole while being electrically insulated from the conductive stem. The signal lead passes through the flexible insulating layer to be joined to the connecting portion. The flexible insulating layer is in contact with the connecting portion, the signal lead, and the surface of the conductive stem.

Abstract: A quantum cascade laser includes a laser structure including laser waveguide structures and a first terrace region; first electrodes; pad electrodes; and wiring metal conductors. The laser structure includes first, second and third regions arranged in a direction of a first axis. The third region is disposed between the first and second regions. The first region has a first end facet disposed at a boundary between the first and third regions. The first end facet extends in a direction intersecting with the first axis. The second region has a second end facet disposed at a boundary between the second and third regions. The second region includes the laser structure. The pad electrodes are disposed on the first terrace region. The first electrodes are disposed on the laser waveguide structures. Each of the pad electrodes is connected to one of the first electrodes through one of the wiring metal conductors.

Abstract: An exemplary bridging inter-connector establishes electrical connections between conductors on a PCB and aligned conductors on a first board mounted to the PCB. A flexible non-conductive sheet covers at least a portion of these conductors. Separated conductive strips on the sheet that are dimensioned to align with and engage at least a portion of both the aligned conductors. A thin film of a bonding agent is disposed on the separated conductive strips and located to engage at least a portion of both aligned conductors to form a conductive connection.

Abstract: An intra-cavity doubled OPS-laser has a laser-resonator including a birefringent filter (BRF) for coarse wavelength-selection, and an optically nonlinear (ONL) crystal arranged for type-II frequency-doubling and fine wavelength-selection. Laser-radiation circulates in the laser-resonator at one of a range of fundamental wavelengths dependent on the resonator length. The ONL crystal has a transmission peak-wavelength dependent on the crystal temperature. Reflection of circulating radiation from the BRF is monitored. The reflection is at a minimum when the ONL crystal transmission-peak wavelength is at the circulating radiation wavelength. The temperature of the ONL crystal is selectively varied to maintain the monitored reflection at about a minimum.

Abstract: An optical module includes: a wiring substrate that has a wiring pattern including a connecting portion and is arranged on an optical subassembly so as to be electrically connected thereto; and a flexible insulating layer formed between the optical subassembly and the wiring substrate. The optical subassembly includes: a conductive stem that has a surface opposed to the wiring substrate, the conductive stem being shaped so that the surface has a through hole opened therein and being connected to a reference potential; and a signal lead for transmitting a signal, the signal lead passing through the through hole while being electrically insulated from the conductive stem. The signal lead passes through the flexible insulating layer to be joined to the connecting portion. The flexible insulating layer is in contact with the connecting portion, the signal lead, and the surface of the conductive stem.

Abstract: Systems, and apparatus for adding reflection based pre-emphasis to a laser driver. In one aspect, a device includes a load (e.g. a laser) having a load impedance, a first end of a transmission line connected to the load, and a reflective impedance element connected to a second end of the transmission line. The reflective impedance element has a given impedance value that differs from the transmission line's characteristic impedance, and the characteristic impedance differs from the load impedance. This mismatch causes reflections between the reflective impedance element and the load. The reflections between the reflective impedance element and the load combine with an incident signal at the load to create a target signal having a target spectral shape.

Abstract: Systems, devices, and methods for hybrid anti-clipping in optical links in hybrid fiber-coaxial (HFC) networks are disclosed. A hybrid anti-clipping circuit can be included in both the uplink and downlink paths of the HFC network to avoid driving the laser in the optical link above a clipping threshold. The anti-clipping circuit can compare the average, or RMS, input power level and the power envelope of a RF input signal to a clipping threshold associated with the particular laser module being used. If the average power is above the clipping threshold, then the input signal can be attenuated proportionally to avoid clipping. If peaks in the power envelope are above the clipping threshold, then the bias current of the laser module can be adjusted to avoid clipping. Accordingly, the modes of anti-clipping circuit operation include applying attenuation to the input signal and/or adjusting the laser module bias current.

Abstract: Disclosed herein is a laser driving circuit, including: a plurality of laser driving video current generation circuits configured to generate a plurality of kinds of laser driving current for driving a plurality of laser light sources configured to emit laser light having wavelengths different from each other based on an inputted video signal; a high frequency superposition section configured to superpose a high frequency signal having a frequency higher than a frequency band of the video signal on the laser driving current generated by the laser driving video current generation circuits; and a waveform correction section configured to correct a waveform of the high frequency signal.

Abstract: A pulse light source includes: a master laser that outputs a master laser light pulse whose repetition frequency is controlled to a predetermined value; a slave laser that outputs a slave laser light pulse; a phase comparator that detects a phase difference between an electric signal having a frequency of the predetermined value, and an electric signal based on a light intensity of the slave laser light pulse; a loop filter; an adder that adds a repetition frequency control signal having a certain repetition cycle, to an output from the loop filter; and a phase comparator that measures a pulse phase difference which is a phase difference between the master laser light pulse and the slave laser light pulse. A magnitude of the repetition frequency control signal is controlled such that the measured pulse phase difference matches with a target value of the pulse phase difference.

Abstract: Disclosed herein is a laser driving circuit, including: a plurality of laser driving video current generation circuits configured to generate a plurality of kinds of laser driving current for driving a plurality of laser light sources configured to emit laser light having wavelengths different from each other based on an inputted video signal; a high frequency superposition section configured to superpose a high frequency signal having a frequency higher than a frequency band of the video signal on the laser driving current generated by the laser driving video current generation circuits; and a waveform correction section configured to correct a waveform of the high frequency signal.

Abstract: A wiring is located on a multilayer ceramic substrate. A ceramic block is located on the multilayer ceramic substrate. Electronic parts, including a semiconductor laser, are located on a surface of the ceramic block. A wiring located on the surface of the ceramic block connects some of the electronic parts to the wiring. A metallic cap with a glass window is located on the multilayer ceramic substrate. This metallic cap covers the ceramic block and the electronic parts, including the semiconductor laser.

Abstract: The laser mount arrangement can have a laser bar and a driver positioned adjacent to one another and secured against a connection face of a heat sink base. The heat sink base is connected to and forms a first electrical connection between the laser bar and the driver. A second electrical connection is also provided between the laser bar and the driver opposite the heat sink base, which can be in the form of a flexible metal sheet with a narrow upward fold. This arrangement can provide a low inductance path for the current.

Abstract: A temperature-compensated laser driving circuit for driving a laser component is provided. The temperature-compensated laser driving circuit includes: a temperature compensation circuit, configured to generate a second current based on a first current and a temperature-independent current; and a modulation current generating circuit, configured to generate a modulation current based on the second current, and calibrate optical power output of the laser component based on the modulation current. The first current is proportional to the absolute temperature. The second current and the first current have a slope relative to the absolute temperature respectively, and the slope of the second current relative to the absolute temperature is larger than of the slope of the first current relative to the absolute temperature.

Abstract: A laser driver circuit having a differential circuit and an output circuit includes a control circuit receiving a regulated supply voltage that also supplies the differential circuit as an input signal. The control circuit generates a feedback voltage across a first resistor to cause a first current to flow in the first resistor having a current value equal or proportional to the modulation current value. The laser driver circuit includes an operational amplifier receiving the feedback voltage and a reference voltage indicative of a desired modulation current value and to generate the regulated supply voltage. The control circuit and the operational amplifier form a feedback control loop to adjust the regulated supply voltage to regulate the feedback voltage to be equal to the reference voltage, thereby regulating the modulation current value to the desired modulation current value.

Abstract: A method for testing a tunable wavelength laser device, which can suppress any error of light transmission characteristics of an etalon, and a tunable wavelength laser device are provided. The method for testing a tunable wavelength laser device is a method for testing a tunable wavelength laser device including a tunable wavelength laser and a wavelength sensing unit having an etalon. The testing method includes a fast step of measuring a free spectral range interval of the etalon, a second step of acquiring a driving condition by tuning a wavelength to a target value provided between a top and a bottom of the free spectral range interval, and a third step of storing the driving condition in a memory.

Abstract: A circuit system includes: a first optoelectronic semiconductor component situated with an n-conductive surface facing an electrically conductive support surface and connected to the support surface in an electrically conductive manner; and a second optoelectronic semiconductor component situated with a p-conductive surface facing the support surface and connected to the support surface in an electrically conductive manner.

Abstract: A semiconductor laser driving circuit supplies a drive current to a semiconductor laser diode connected to an output terminal based on an input signal inputted thereto through an input terminal, thereby controlling the semiconductor laser diode. The semiconductor laser driving circuit includes a first supply portion supplying a bias current, and a first supply signal having a frequency component whose frequency is equal to or lower than a first frequency of the input signal, and a second supply portion supplying a second supply signal having a frequency component whose frequency is higher than a second frequency of the input signal.

Abstract: A laser diode (LD) driver to suppress the excess emission of an LD is disclosed. The LD driver has the shunt configuration with a driving transistor connected in parallel to the LD to shunt the bias current provided to the LD. The driver further provides a protection circuit to divide the bias current when the bias current is active but the driving transistor is turned off at an instant of the power on and off of the LD driver.

Abstract: Systems and methods are provided to efficiently manage power in a laser a driver of an optical network unit (ONU) of a passive optical network (PON). Using information from an allocation map, the expected next allocated schedule for a transmission can be determined. The driver can be efficiently powered down and powered up based on the time remaining between the end of the current burst and the beginning of the next expected burst so that power is not wasted while the laser has no data to transmit.

Abstract: A laser assembly and a method for manufacturing the same are provided according to embodiments of the present disclosure. The laser assembly (900) may comprise a first plate (903) having first projections (918, 928); a printed circuit board assembly (902) including a printed circuit board (912) having first openings (913, 915) and a laser module (100) thereon, and a second plate (901) having second projections (917, 927). The printed circuit board assembly (902) can be retained between the first plate (903) and the second plate (901) by the first projections (918, 928) and the second projections (917, 927). The laser assembly may further comprises a first pad (930) provided between the laser module (100) and the first plate (903) and/or a second pad (920) provided between the laser module (100) and the second plate (901).

Abstract: A fiber laser apparatus in which pump light is introduced into an optical fiber to generate laser light includes a detecting section that detects signal light leaking out from a core of the optical fiber as leakage signal light, a determining section that determines that, in a case where there is a decrease in an intensity of the leakage signal light detected in the detecting section, a failure of the fiber has occurred, and a stopping section that stops, in a case where the determining section has determined that a failure of the fiber has occurred, the introduction of the pump light into the optical fiber. The detecting section detects the leakage signal light leaking out of a High Reflectivity FBG that is provided on a side opposite to an output side of the laser light.

Abstract: Embodiments for driving a laser diode includes generating a bias current having a duty cycle that is less than 100%. The current level of the bias current is insufficient to turn on the laser diode. A drive current is generated and combined with the bias current to turn on the laser diode almost instantly.

Abstract: Systems and methods for performing semiconductor laser annealing using dual loop control are disclosed. The first control loop operates at a first frequency and controls the output of the laser and controls the 1/f laser noise. The second control loop also controls the amount of output power in the laser and operates at second frequency lower than the first frequency. The second control loop measures the thermal emission of the wafer over an area the size of one or more die so that within-die emissivity variations are average out when determining the measured annealing temperature. The measured annealing temperature and an annealing temperature set point are used to generate the control signal for the second control loop.

Abstract: An apparatus of automatic power control for burst mode laser transmitter and method are provided. In one implementation a method includes: generating an output current with a modulation pattern determined by a transmit data and a transmit enable signal, and a modulation level determined by a first control code and a second control code, wherein a light signal is generated in response to the output current; generating a first decision based on a comparison between a photodiode current and the first reference current, a second decision based on a comparison between the photodiode current and the second reference current, wherein the photodiode current is generated in accordance to the light signal; and generating the first control code and the second control code in response to the first decision and the second decision.

Abstract: An improved laser module for a tunable diode laser spectroscopy analyzer. The improvement is a programmable non-volatile memory device (such as an EEPROM device) attached to the module. In addition, an improved method for updating the laser parameters for a tunable diode laser analyzer when a new laser module is installed in the analyzer. The improvement is the step of reading the parameters from a programmable non-volatile memory device (such as an EEPROM device) attached to the module.

Abstract: The present invention provides a laser apparatus capable of improving a scan speed and achieving a scan rate equal to or more than 1 MHz, and an optical tomographic imaging apparatus using the laser apparatus as a light source. The laser apparatus includes a ring resonator, the ring resonator having a structure in which a first modulator, a normal dispersion region, a second modulator and an anomalous dispersion region are arranged in this order, and in this arrangement, a gain medium is included, and being configured so that modulation with respect to the second modulator can be caused to be phase modulation by periodically superimposing phase modulation on modulation with respect to the first modulator.

Abstract: Provided is a method for controlling a laser oscillator. Such a laser oscillator is applicable to a laser processing machine and includes a plurality of oscillator modules each adapted to be driven to oscillate a laser beam. Also, such a laser oscillator is configured to collect laser beams oscillated by driven modules for output. The method includes determining the number of modules to be driven, of the plurality of oscillator modules.

Abstract: A laser chip package structure includes a printed circuit board (PCB), a flexible circuit board, a laser chip and a number of electronic elements. The PCB includes a supporting surface. The flexible circuit board is positioned on the supporting surface and electrically connected to the PCB. The laser chip is positioned on the flexible circuit board and electrically connected to the flexible circuit board. The laser chip is configured to emit a laser beam. The electronic elements are positioned on the flexible circuit board and electrically connected to the flexible circuit board.

Abstract: A compact CO2 slab-laser is contained in a fluid cooled housing having three compartments. One compartment houses discharge electrodes and a laser resonator. Another compartment houses a radio-frequency power supply (RFPS) assembled on a fluid-cooled chill plate and an impedance-matching network. The remaining compartment houses beam-conditioning optics including a spatial filter. The housing and RFPS chill-plate are on a common coolant-fluid circuit having a single input and a single output. The spatial filter is optionally fluid-coolable on the common coolant fluid circuit.

Abstract: An extreme ultraviolet light source apparatus, in which a target material is irradiated with a laser beam from a laser apparatus and the target material is turned into plasma, thereby emitting extreme ultraviolet light, may include a burst control unit configured to control irradiation of the target material is irradiated with the laser beam outputted successively in pulses from the laser apparatus when the extreme ultraviolet light is emitted successively in pulses. The target material is prevented from being turned into plasma by the laser beam while the laser beam is outputted successively in pulses from the laser apparatus when the successive pulsed emission is paused.