Abstract: A load such as an LED and a constant-current source are connected in series with each other between the node of a dc-dc conversion type power supply circuit providing an output voltage and the ground. The constant-current source provides a constant current Io, the magnitude of which can be adjusted. The power supply circuit controls the output voltage such that the voltage drop across the constant-current source serving as a detection voltage becomes equal to a reference voltage. Thus, the load current can be varied within a predetermined range while avoiding the power loss due to an increase in the load current, thereby always permitting efficient operation of the load.

Abstract: A current output of a drive signal, modulated between two current settings, is applied to a laser diode, e.g. VCSEL. The settings are selected such that laser diode's power output meets the average power and peak power limits of the eye safety standards. The drive signal having a duty cycle toggling between the two settings. The duty cycle is selected such that the average and peak power limits are met for the given upper current setting. The drive circuit may include an analog modulator or digital analog converter (DAC) for maintaining the lower and upper current settings. When the drive circuit is implemented as an integrated circuit, the DAC may be incorporated into the IC. The sensitivity of the DAC is selected to maintain the desired lower and upper current settings.

Abstract: A plurality of discharge sections are formed in an optical resonance space and are provided with electrodes that are mutually different in for example shape, size and construction. Laser medium gas flows through a circulatory passage passing through a fan and heat exchangers. Mutually different modes can be obtained when discharge is produced independently in the discharge sections. When discharge is produced in both of the discharge sections, the various intermediate modes can be obtained, in accordance with the distribution of power supplied from power sources for discharge excitation that are independently operated.

Abstract: A laser diode driving circuit includes two chip capacitors disposed in the vicinity of one side portion of an IC along which a high voltage power supply terminal, a low voltage power supply terminal and a driving signal output terminal are disposed. One end portion of each of the chip capacitors is connected to the high voltage power supply terminal and the other end portion of each of the chip capacitors is connected to the low voltage power supply terminal. The chip capacitors are adapted for serving to reduce a ripple component superposed on a power supply voltage when a switching element is operated. The chip capacitors are disposed so that the distance between itself and the high voltage power supply terminal, the low voltage power supply terminal and the driving signal output terminal is equal to or shorter than 10 mm.

Abstract: Methods and systems and apparatuses for reducing power consumption, in an environment including a laser driver that drives a laser diode, are provided. The voltage drop across a laser diode, driven by a laser driver, is monitored. This enables a supply voltage, used to power the laser driver, to be appropriately adjusted, based at least in part on the monitored voltage drop. For example, the supply voltage is increased when the monitored voltage drop across the laser diode increases, and decreased when the monitored voltage drop across the laser diode decreases.

Abstract: The invention is directed to an arrangement for generating pulsed currents for gas discharge pumped radiation sources, particularly with high repetition rates and high current strengths for generating plasma emitting EUV radiation.

Abstract: A simply structured apparatus according to the present invention corrects an overdrive power level. A main controller allows an overdrive power generator to set an overdrive power current to zero, allows a base power controller to control a base power current with the target value of a base power monitor level set to a desired overdrive power level. When the base power monitor level has reached the target value, the main controller allows said overdrive power generator to increase the overdrive power current until a base power control signal monitored by a base power control signal monitor reaches a value corresponding to a desired base power level.

Abstract: An optical module includes a housing, a Peltier device, a semiconductor light-generating device, an optical waveguide, and a power supply circuit device. The housing has first and second power supply terminals. The Peltier device is provided in the housing. The semiconductor light-generating device is provided on the Peltier device. The optical waveguide is optically coupled to the semiconductor light-generating device. The power supply circuit device is provided in the housing and connected to the semiconductor light-generating device. The semiconductor light-generating device and Peltier device are connected in series between the first and second power supply terminals. In the light-generating module, current flows in one of the semiconductor light-generating device and the Peltier device, and then the current flows in the other of the semiconductor light-generating device and the Peltier device.

Abstract: A laser diode driving device of the present invention can appropriately shorten the rising time and the falling time of a laser diode drive current in a range from a small current region to a large current region. In synchronization with the addition of an original input current from an input constant current source to the laser diode drive current amplifier, a differentiated current is added to the input current through a differentiation circuit and a pull-in type V-I conversion circuit, whereby the rising of a laser diode drive current is made abrupt. Furthermore, by increasing a gate potential of an input PchMOS transistor constituting the laser diode drive current amplifier by a differentiation circuit and a push-out type V-I conversion circuit in synchronization with the disconnection of an input current, the falling of a laser diode drive current is made abrupt.

Abstract: Method and arrangement are disclosed for a power distribution network for distributing power to VCSELS on an optoelectronic chip that maintains a constant bias voltage to the VCSELs. More particularly, the power distribution network includes an H-tree network for directing a power signal. The H-tree network includes a primary input for receiving the power signal and at least one level, with terminal nodes coupled to the last level, and each level includes a plurality of segments. Each segment of a respective level is equal in length and the total number of segments from the primary input to each terminal node is the same. Since the distance from the primary input to each terminal node is equal, greater bias voltage uniformity is provided to the terminal nodes. A similar distribution network is used for the ground connection.

Abstract: A semiconductor laser driving circuit drives a plurality of semiconductor laser devices having different objective operating voltages, and has a power source for generating power voltages for the semiconductor laser devices, a power voltage changeover means for changeover from one of the power voltages to another, a current amplification section for supplying a driving current to the semiconductor laser device with the power voltage so that the semiconductor laser device comes to have its respective objective operating voltage.

Abstract: A method and circuit for measuring the optical modulation amplitude in the operating region of a laser diode is described. The method utilises two measurements of OMA, each measurement being related to the slope in a specific portion of the operating region of the power/current characteristic curve of the laser diode. By combining the two measurement values, the invention provides a 1 measurement for OMA in the operating region of the laser diode that allows for the presence of a non-linear response in the region.

Abstract: A method for controlling a modulation current and a bias current of a laser driver includes generating a differential signal that has a voltage offset, for setting the modulation current, over a pair of differential inputs from a pre-driver circuit to a laser driver circuit. A voltage is generated for setting the bias current over a bias/monitor pin from the pre-driver circuit to the laser driver circuit. The voltage offset is sensed at the laser driver circuit and the modulation current is set based on the voltage offset. The voltage is sensed at the laser driver circuit and the bias current is set based on the voltage. A photo current is delivered over the bias/monitor pin from the laser driver circuit to the pre-driver circuit wherein no interaction occurs between the photo current and the voltage. The voltage is then modified based on the photo current.

Abstract: The present invention provides a laser machining apparatus in a simple structure which can properly carry out laser machining by irradiating a laser beam easily at a predetermined energy density to a machining-target site in a predetermined range, and in addition, which can be downsized and can be kept with easy maintenance and has enhanced durability. The apparatus includes: a semiconductor stack 1 comprising a plurality of semiconductor laser elements; and a controller for controlling emission of the laser beam emitted from each of the semiconductor laser elements. The semiconductor stack 1 is divided into a plurality of blocks B11, B12, B13, B14 in correspondence with the machining-target site of a work piece. The controller controls the irradiation of the laser beam from each of the blocks B11, B12, B13, B14 to be changeable in terms of time.

Abstract: Driver circuits of the present invention provide current to drive laser diodes. The output current of the driver circuit includes a data signal and a low frequency tone signal. The low frequency tone signal is within the bandwidth of a power control feedback loop. The tone signal introduces low frequency noise into the output signal of the driver circuit. The low frequency noise causes jitter at the zero crossing points of the driver circuit output signal. A laser driver circuit of the present invention provides a compensation current to a laser diode. The compensation current is out of phase with the tone signal. The compensation current eliminates the low frequency noise in the output signal of the laser driver circuit.

Abstract: A method of controlling a tuneable laser that has been characterized with respect to one or more suitable laser operation points. Each operation point is determined by the manner in which the different laser sections are controlled, in order to operate the laser at a predetermined operation point. The voltage across the different laser section is determined for different operation points when controlling the laser, and the voltages across the different laser sections are held constant when the laser is in operation to maintain a predetermined operation point.

Abstract: A laser driver for laser sensing system having two lasers on a single PCB, thermo-electric temperature control, rapid activation, and pulse power and duration safety tables embedded in the microprocessor controller.

Abstract: A laser system includes a series coupled laser diode pair, first and second current regulators, and a power supply. The first current regulator controls current supplied to the laser diode pair. The second current regulator selectively diverts a portion of the supplied current away from a first laser diode of the laser diode pair. The power supply adaptively adjusts a level of a supply voltage applied across the series coupled laser diode pair.

Abstract: In a gas laser device, a compensation time according to electric charges accumulated in a charging capacitor is calculated and, when the compensation time lapsed from a time when an outer trigger was input, a compensation trigger is output to a semiconductor switch to electrically connect the charging capacitor and a first-stage capacitor, whereby a time between the input of the outer trigger and the occurrence of light emission across discharge electrodes becomes constant in each pulse and a semiconductor substrate can be exposed to light with higher accuracy even when any components of a pulse power source are affected by a temperature change.

Abstract: A high-speed laser driver for signal noise on the electrical analysis point. The driver includes a power supply, for providing a test voltage in the system; a pulse generator, for providing a test frequency in a noise testing of the system; a regulable test IC with different signal pads capable of regulable testing signal noise with the test frequency from the pulse generator and the test voltage from the power supply in a plurality of built-in specific structures, under the basis of an assigned current standard; and a digital detection device with a display, for displaying and recording the result of the regulable test.

Abstract: A long pulse power system for gas discharge lasers. The system includes a sustainer capacitor for accepting a charge from a high voltage pulse power source. A peaking capacitor with a capacitance value of less than half the sustainer capacitance provides the high voltage for the laser discharge.

Abstract: A laser driver circuit includes a pair of transistors having base electrodes respectively coupled to a differential input signal. The respective collector electrodes are coupled to a first power supply rail and the respective emitter electrodes are coupled to a laser diode via respective impedances and to respective controllable current sources to provide an average modulation voltage at the more positive of the emitter electrodes. By having the transistors in an emitter follower configuration, rather than the usual collector open collector configuration, the problem of mismatch between the output impedance of the transistors and the input impedance of the laser diode is reduced.

Abstract: A molecular fluorine laser system includes a discharge tube filled with a gas mixture including molecular fluorine and at least one buffer gas and having a total pressure of less than substantially 2500 mbar, multiple electrodes within the discharge tube, a pulsed discharge circuit connected to the electrodes for energizing the gas mixture, a line-selection optic for selecting one of multiple closely-spaced lines around 157 nm emitted from the discharge tube, and a laser resonator including the line-selection optic and the discharge tube for generating a beam of laser pulses having a wavelength around 157 nm at a bandwidth of less than 0.6 pm.

Abstract: The present invention provides an excimer laser capable of producing a high quality pulsed laser beam at pulse rates of about 4,000 Hz at pulse energies of about 5 mJ or greater. A preferred embodiment is an ArF excimer laser specifically designed as a light source for integrated circuit lithography. An improved wavemeter with special software monitors output beam parameters and controls a very fast PZT driven tuning mirror and the pulse power charging voltage to maintain wavelength and pulse energy within desired limits. In a preferred embodiment two fan motors drive a single tangential fan which provides sufficient gas flow to clear discharge debris from the discharge region during the approximately 0.25 milliseconds between pulses.

Abstract: A driving control circuit for a light-emitting device. The circuit generates a high-speed modulated current to drive the light-emitting device. The circuit includes an adjustable gain circuit, a current output circuit, and a level control circuit. The adjustable gain circuit receives a digital signal and generates an output voltage controlled by a first control signal and a second control signal. The current output circuit includes a first transistor. A gate of the first transistor is coupled to the adjustable gain circuit, which adjusts a range of the gate voltage to generate the high-speed modulated current, and the level control circuit sets the voltages of the first control signal and the second control signal.

Abstract: A F2-laser includes a discharge chamber filled with a gas mixture including molecular fluorine for generating a spectral emission in a wavelength range between 157 nm and 158 nm including a primary line and a secondary line, multiple electrodes coupled with a power supply circuit for producing a pulsed discharge to energize the molecular fluorine, a resonator including the discharge chamber and an interferometric device for generating a laser beam having a bandwidth of less than 1 pm, and a wavelength monitor coupled in a feedback loop with a processor for monitoring a spectral distribution of the laser beam. The processor controls an interferometric spectrum of the interferometric device based on the monitored spectral distribution such that sidebands within the spectral distribution are substantially minimized.

Abstract: An optical transmitter of a subscriber optical interface and an optical receiver of a laser transceiver node can be designed to a frequency of data that is formatted according to a predetermined network protocol, that is encoded with a predetermined coding scheme, and that is transmitted according to a predetermined data transmit timing scheme. The frequency of data is an occupied frequency of a protocol when the data comprises a maximum number of like bits permitted by the protocol. An optical transmitter and optical receiver can be designed to a lowest occupied frequency of data that is encoded with 8B/10B encoding, and that is propagated upstream according to time division multiple access (TDMA). In this way, upstream optical communications can be maximized for speed.

Abstract: A saturable reactor is in a conductive state or has a magnetic switching function depending on the direction of the current flowing through it. Also provided is a power source apparatus for pulse laser utilizing the satiable reactor.

Abstract: A laser system includes a series coupled laser diode pair, first and second current regulators, and a power supply. The first current regulator controls current supplied to the laser diode pair. The second current regulator selectively diverts a portion of the supplied current away from a first laser diode of the laser diode pair. The power supply adaptively adjusts a level of a supply voltage applied across the series coupled laser diode pair.

Abstract: A solid-state laser comprises an excitation light source having a semiconductor laser array, a plurality of chopper circuits arranged between a direct-current power supply and an output terminal of the semiconductor laser array and connected in parallel with each other, for applying resultant power of the chopper circuits to the semiconductor laser array, a current controller for controlling the plurality of chopper circuits to modulate the resultant power at time resolution ranging from 1 &mgr;s to 100 &mgr;s, a solid-laser medium excited by a laser beam emitted from the semiconductor laser array, and a pair of mirrors for resonating a laser beam generated by exciting the solid-state medium.

Abstract: A charging and discharging circuit for a pulse laser which enables the pulse laser to increase an oscillation frequency.

Abstract: An emission timing control apparatus for a pulsed laser including a magnetic pulse compression circuit having a switching section for carrying out a switching operation to connect and disconnect a charging power source to and from the magnetic pulse compression circuit. The pulsed laser executes pulsed laser oscillation at a prescribed repetition frequency by turning on the switching section with a pulse oscillation synchronizing signal having the prescribed repetition frequency received from a semiconductor exposure apparatus, in which the emission timing control apparatus includes a reference delay time setting section for setting a prescribed reference delay time, and delay section for delaying a pulse oscillation synchronizing signal received from the semiconductor exposure apparatus by the time difference &tgr; calculated in the delay time calculating section and outputting to the switching section.

Abstract: A peaking capacitor layout in which a discharge energy is not lowered even when peaking capacitors are decreased in their capacitance, increased in their number and disposed in a plurality of rows. The discharge energy is uniformly distributed to obtain a stable laser power. A peaking capacitor group in a first row formed of a plurality of peaking capacitors and a peaking capacitor group in a second row formed of a plurality of peaking capacitors are disposed in a plurality of rows (two rows) in a direction in which a length of a loop changes. The capacitance of the peaking capacitors forming the second row having a long loop is adjusted to be smaller than that of the peaking capacitors forming the first row having a short loop. And, the capacitance of the peaking capacitors in the first and second rows are adjusted so that the distribution of the capacitance of the peaking capacitors becomes uniform along the longitudinal direction of the discharge electrodes.

Abstract: A tunable injection seeded very narrow band F2 lithography laser. The laser combines modular design features of prior art long life releasable lithography lasers with special F2 line narrowing and tuning techniques applied to a seed beam operated in a first gain medium which beam is used to stimulate narrow band lasing in a second gain medium to produce a very narrow band laser beam useful for integrated circuit lithography.

Abstract: A semiconductor laser excitation solid state laser apparatus is provided which can generate a stable and highly efficient laser beam of high power. The laser apparatus includes a solid state laser element 2 containing an active medium, a semiconductor laser 1 for optically exciting the semiconductor laser 1, a power supply 8 for supplying electric power to the semiconductor laser 1, and an optical resonator 9, 10 for taking out a laser beam from the optically excited solid state laser element 2. When the semiconductor laser 1 is pulse-operated to pulse-excite the solid state laser element 2, current supplied to the semiconductor laser 1 is changed within one pulse.

Abstract: A simmer circuit 18 comprises a power supply unit 54 for the supply of a simmer current Is to an excitation lamp 22 and a control unit 56 for the control of the current value of the simmer current Is. In the control unit 56, a current detection signal Vs from a current sensor, e.g., a Hall CT 70 attached to the power supply unit 54 is fed via a buffer amplifier 72 for impedance conversion to a non-inversion input terminal of an operational amplifier 82 for signal amplification. The amplification factor &mgr; of the operational amplifier 82 differs depending on which one is selected from three switches 84, 86 and 88. A CPU 38 selects the switch 84 when switching the simmer current Is to 0.3 A for “low speed zone”, selects the switch 86 when switching to 2 A for “medium speed zone” and switches 88 when switching to 5 A for “high speed zone”.

Abstract: A reliable, modular, production quality F2 excimer laser capable of producing, at repetition rates in the range of 1,000 to 2,000 Hz or greater, laser pulses with pulse energies greater than 10 mJ with a full width half, maximum bandwidth of about 1 pm or less at wavelength in the range of 157 nm. Laser gas concentrations are disclosed for reducing unwasted infrared emissions from the laser. Also disclosed are UV energy detectors which are substantially insensitive to infrared light. Preferred embodiments of the present invention can be operated in the range of 1000 to 4000 Hz with pulse energies in the range of 10 to 5 mJ with power outputs in the range of 10 to 40 watts. Using this laser as an illumination source, stepper or scanner equipment can produce integrated circuit resolution of 0.1 &mgr;m or less. Replaceable modules include a laser chamber and a modular pulse power system.

Abstract: An input signal is supplied to an adder circuit via a gain control amplifier and integrating amplifier and output signals of the gain control amplifier and the integrating circuit are added together by the adder circuit. An output signal of the adder circuit is supplied to a driving current generating circuit. The driving current generating circuit is constituted by first and second transistors whose bases and emitter are commonly connected. An externally attached resistor monitors a driving current flowing in the collector of the transistor constructing the driving current generating circuit and feeds back the current to the gain control amplifier. Therefore, the current control operation of high precision can be attained by use of a part of the driving current.

Abstract: A power system for a laser source comprises a plurality of semiconductor lasers or at least one laser array with plurality of independently, electrically addressable emitters. A power supply is independently connected to each of the laser emitters. A fuse device is associated with each of the laser emitters so that an electrical short of any one emitter of a laser will not cause a short to or change the power supplied to other emitters of the laser source.

Abstract: A power supply is provided for use in a laser system including a gas ion laser tube which requires a filament voltage provided by an output section of the power supply. The filament voltage provided should not exceed a maximum AC filament voltage specified for the laser tube. The power supply is configured to receive AC utility power using one of at least first and second AC utility power sources having different first and second intended fixed magnitudes and which utility sources vary in amplitude from the intended fixed magnitudes over corresponding first and second source voltage ranges. The power supply is configured to include a power control arrangement which automatically controls the output section to generate an auto-ranging AC filament voltage from either of the first and second utility sources to be supplied as the filament voltage.

Abstract: A laser diode system comprising a voltage source, an inductor connected to the output of the voltage source, an integrator circuit connected in series with the inductor, and a laser diode. The integrator circuit filters out noise from the voltage source, and includes a first resistor, an amplifier, a second resistor, and first and second capacitors. The second capacitor has one lead connected to the input lead of the inductors and the other lead attached to the input of the first resistor. The output lead of the first resistor is connected to the negative input lead of the amplifier, and to the input lead of the first capacitor. The positive input lead of amplifier OP is connected to the output of the inductor (and the anode of the laser diode). The outputs of amplifier and the first capacitor are connected to the input of the second resistor, which has an output connected to the anode of the laser diode. The cathode of laser diode is tied to circuit common.

Abstract: A burst mode optical transmitter circuit comprises a semiconductor laser, a photodiode for monitoring the light output from the semiconductor laser, a current-voltage converting circuit for converting the current detected by the photodiode into a voltage, an APC amplifier, a holding circuit for holding, as a current control signal, the output signal from the APC amplifier, a driving circuit for supplying a driving current to the semiconductor laser according the current control signal from the holding circuit and the the data input in the burst mode, and a data interruption detecting circuit for detecting an interrupt period of the data input to the driving circuit to reset the holding circuit, in which the current control signal held in the hold circuit is reset by the reset signal, whereby a stable burst optical transmission can be performed stably with a simple construction.

Abstract: The present invention provides a reliable modular production quality excimer laser capable of producing 10 mJ laser pulses in the range of 1000 Hz to 2000 Hz or greater. Replaceable modules include a laser chamber; a pulse power system comprised of three modules; an optical resonator comprised of a line narrowing module and an output coupler module; a wavemeter module, an electrical control module, a cooling water module and a gas control module. Important improvements have been provided in the pulse power unit to produce faster rise time and improved pulse energy control. These improvements include an increased capacity high voltage power supply with a voltage bleed-down circuit for precise voltage trimming, an improved communication module that generates a high voltage pulse from the capacitors charged by the high voltage power supply and amplifies the pulse voltage 23 times with a very fast voltage transformer having a secondary winding consisting of a single four-segment stainless steel rod.