Abstract: An RF powered CO2 gas-discharge laser includes discharge electrodes and a lasing gas mixture between the electrode. The lasing gas mixture is ionized when the RF power is applied to the electrodes and laser action is initiated when the RF power has been applied for a duration sufficient to ignite a discharge in the lasing gas mixture. The gas mixture is pre-ionized by periodically applying the RF power to the electrodes for a predetermined period during which ignition of a discharge is not expected to occur. RF power reflected back from the electrodes is monitored. If the monitored power falls below a predetermined level indicative of the imminent onset of laser action before the predetermined duration has elapsed, application of the RF power to the electrodes is terminated to prevent the laser action from occurring.

Abstract: Disclosed are systems and methods for improving wavelength control in tunable laser sources. Embodiments of the systems and methods include delivering a fraction of the light output from the laser to an optical filter subsystem. The optical filter subsystem is capable of outputting at least one filter response signal, and comprises 2 complementary optical etalon filters with nominally identical free spectral ranges but offset by nominally one third of the free spectral range. The filter response signal is processed in a control unit which executes a control algorithm to generate a tuning signal that is used to control the wavelength of the laser.

Abstract: A pulse width modulation method for controlling the output power of a pulsed gas discharge laser powered by a pulsed RF power supply comprises delivering a train of digital pulses to the RF power supply. Each pulse in the train has an incrementally variable duration. The power supply is arranged to deliver a train of RF pulses corresponding in number and duration to the train of digital pulses received. The average power in the RF-pulse train can be varied by incrementally varying the duration of one or more of the digital pulses in the digital pulse train. The train of RF pulses is used to power a gas discharge laser. The gas discharge laser outputs a pulse train corresponding to the RF pulse train.

Abstract: Techniques and devices based on optical resonators made of nonlinear optical materials and nonlinear wave mixing to generate optical combs that are stabilized relative to an atomic reference.

Abstract: A method to control an LD (laser diode) is disclosed. The method compares the operating temperature of the LD with a transition temperature. When the former temperature exceeds the latter, the modulation current is set based on the bias current, which is independently determined by the APC loop. On the other hand, the operating temperature is less than the transition temperature; the modulation current is determined by the operating temperature.

Abstract: The invention relates to a laser amplification system for generating retrievable laser pulses having at least one laser source, in particular with a pulse selector arranged downstream thereof for the targeted selection of amplifiable laser pulses, a laser medium for amplifying laser pulses generated by the laser source and a loss modulator, wherein the loss modulator is arranged and connected such that said modulator modulates the amplification of the laser pulses by the laser medium by loss generation so that the retrievable laser pulses are provided with a predefined pulse time and/or pulse energy. Before an amplification process for one of the laser pulses, the current amplification of the laser medium is determined and the loss generation is controlled by the loss modulator depending on the current amplification of the laser medium.

Abstract: A laser bias control and monitoring circuit receives a monitor diode current on an input node and generate a bias current for a laser diode on an output node where the monitor diode current flows into (positive polarity) or out of (negative polarity) the input node. The laser bias control and monitoring circuit includes a polarity independent current sensing circuit configured to receive the monitor diode current in either positive or negative polarity and to generate a normalized output current having a magnitude proportional to a magnitude of the monitor diode current. In this manner, the laser bias control and monitoring circuit can be used with laser diode and monitor diode combination in either the common anode or the common cathode configuration, or with the monitor diode current being provided from the anode or cathode of the monitor diode. No reprogramming or reconfiguration of the circuit is required.

Abstract: A control system for improving and stabilizing Fourier domain mode locking (FDML) operation. The control system may also provide regulation of FDML operational parameters such as filter tuning, laser gain, polarization, polarization chromaticity, elliptical polarization retardance, and/or dispersion. The control system may be located internal to or external from the FDML laser cavity.

Abstract: A laser diode write driver is described.

Abstract: A digital-to-analog (DA) converter includes: an analog output section that generates an output current corresponding to a value of a digital signal in response to a bias voltage and outputs an analog signal which is obtained from the output current by current-to-voltage conversion; a current source; a current control section that converts a current from the current source to a voltage signal and outputs the voltage signal as the bias voltage; and a sample and hold circuit section that samples and holds the bias voltage from the current control section and supplies the held bias voltage to the analog output section.

Abstract: Laser light wavelength control is provided by periodically predicting a next position of a light controlling prism using a model of the prism's motion characteristics. The prediction is then updated if a measurement of laser output wavelength is obtained. However, because the predictions are made without waiting for a measurement, they can be made more frequently than the laser firing repetition rate and the prism can be repositioned at discrete points in time which can occur more frequently than the laser firing events. This also reduces performance degradation which may be caused by being one pulse behind a laser measurement and the resultant laser control signal being applied.

Abstract: A automatic power control loop comprises a photo diode used for sensing a light intensity of a laser diode to generate a feedback current, a switch selector used for selecting one among a plurality of predetermined currents according to a control signal generated by a controller, a transducer used for transferring a current different between the feedback current and the selected predetermined current into a load voltage, a comparator used for comparing the load voltage with a reference voltage to generate a comparison signal, a counter used for counting a count value according to the comparison signal and the control signal, and a laser diode driver used for generating a corresponding bias current in response to the count value to drive the laser diode. Thereby, the bias current will be adjusted within an allowable range, so that the light source of the laser diode can maintain a constant light intensity.

Abstract: A multi-beam laser light-intensity control circuit includes laser diodes; a light-receiving element for receiving a laser beam emitted from each laser diode and outputting a current corresponding to the light intensity of the received laser beam; and an automatic power control circuit for automatically controlling output power of each laser diode based on the current output from the light-receiving element.

Abstract: The present patent application provides a low power consumption pump driving circuit including a laser cooling chip, a PMOS transistor, a NMOS transistor, a LC filter circuit, a laser, and a voltage sampling circuit. The pulse width modulating signal generated by the laser cooling chip and the control terminal of the PMOS transistor are connected to the gate of the PMOS transistor. The source of the PMOS transistor is connected to a power supply. The drain of the PMOS transistor is connected to the LC filter circuit. The other terminal of the LC filter circuit is connected to the anode of the laser. The cathode of the laser is connected to the drain of the NMOS transistor. The source of the NMOS transistor is connected to the ground. One terminal of the voltage sampling circuit is connected to the laser. The other terminal of the voltage sampling circuit is connected to the laser cooling chip.

Abstract: The present invention comprises, in various embodiments, systems and methods for shutting down a laser system in an intelligent and flexible manner. An intelligent laser interlock system includes both hardwired components, and intelligent components configured to execute computing instructions. The hardwired components and the intelligent components are configured to shutdown the laser system to one or more alternative shutdown states in response to one or more interlock signals.

Abstract: A feedback control module for stabilizing a carrier-envelope phase of an output of a laser oscillator system comprises a first photodetector, a second photodetector, a phase stabilizer, an optical modulator, and a thermal control element. The first photodetector may generate a first feedback signal corresponding to a first portion of a laser beam from an oscillator. The second photodetector may generate a second feedback signal corresponding to a second portion of the laser beam filtered by a low-pass filter. The phase stabilizer may divide the frequency of the first feedback signal by a factor and generate an error signal corresponding to the difference between the frequency-divided first feedback signal and the second feedback signal. The optical modulator may modulate the laser beam within the oscillator corresponding to the error signal. The thermal control unit may change the temperature of the oscillator corresponding to a signal operable to control the optical modulator.

Abstract: An optical scanning apparatus includes a light source configured to emit a plurality of laser beams from a plurality of light emitting parts, a beam shaping unit configured to shape the laser beams emitted from the light source, a detection unit provided outside the light source and configured to detect an amount of a laser beam that is not shaped by the beam shaping unit in the laser beams emitted from the light source in an area outside the beam shaping unit, and a light amount control unit configured to control amounts of the laser beams emitted from the light source based on a detection result detected by the detection unit. The detection unit includes a plurality of light-sensitive elements. The light amount control unit controls the light amounts of the laser beams emitted from the light source based on detection results of the light-sensitive elements.

Abstract: Particular embodiments of the present invention relate generally to semiconductor lasers and laser projections systems and, more particularly, to schemes for controlling semiconductor lasers. According to one embodiment of the present invention, a laser having a gain section, a phase section and a wavelength selective section is configured for optical emission of encoded data. The optical emission is shifted across a plurality of laser cavity modes by applying a quasi-periodic phase shifting signal I/V? to the phase section of the semiconductor laser. The amplitude of the quasi-periodic signal transitions periodically between a maximum drive level and a minimum drive level at a frequency that varies randomly over time.

Abstract: A semiconductor laser driving device that drives a semiconductor laser with a driving current output from a driving current output terminal is disclosed. The semiconductor laser driving device includes a driving current monitoring terminal configured to output a driving current monitoring current having a value of 1/? of the driving current; a current-voltage conversion resistor connected to the driving current monitoring terminal and configured to convert the driving current monitoring current having the value of 1/? of the driving current into a corresponding driving current monitoring voltage; and a detector configured to generate a reference voltage and detect whether the corresponding driving current monitoring voltage has reached the reference voltage.

Abstract: A laser emission device comprises a plurality of laser elements, a plurality of laser driving power supplies, optical elements which uniformize the laser light amount distributions of laser lights, plural light-receiving elements, a measurement unit which measures at least the relations between the operation current values of the laser elements and the output power values of the laser lights with respect to the operation current values, and the control unit operates the laser driving power supplies according to the operation current values and the output power values so as to make the light output powers of the laser elements different from each other.

Abstract: In a pulsed laser diode driver an energy storage capacitor is continuously being charged to a supply voltage Vr. When a pulse is initiated, energy stored in the capacitor is delivered to the laser diode load. The capacitor voltage Vd at the end of a pulse is used to control Vr to ensure that Vd is maintained above a minimum voltage Vm required to ensure operation of a current control device (such as FET) just above saturation. Test pulses (such as with attenuated currents or reduced pulsewidth) may be fired to determine an initial optimum value for Vr. After a test pulse, a slightly high estimate for Vr may be used and may be iterated (incremented) down to an optimum value Vm during a firing burst. A digital processor may be used to calculate and store data to optimize the performance. Various embodiments are disclosed.

Abstract: A light source device including a semiconductor light emitting element and a control section for controlling the semiconductor light emitting element in accordance with an input value. The control section includes a supply section that supplies the semiconductor light emitting element with a drive current based on the input value and an estimated threshold current of the semiconductor light emitting element, and an estimation section that obtains the estimation of the threshold current using the drive current and the amount of light detected to be emitted from the semiconductor light emitting element.

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: A method of estimating an injection power of seed light injected into an injection-seeded transmitter. A back face monitoring (BFM) response of the injection-seeded transmitter is determined, and data representative of the BFM response stored in a memory. During run-time, a controller of the injection-seeded transmitter, detects a temperature of the injection-seeded transmitter and an instantaneous BFM current. BFM response data is obtained from the memory based on the detected temperature, and the seed light injection power estimated based on the obtained data and the detected instantaneous BFM current.

Abstract: A transistor outline (TO) package includes a housing having a window and a substrate. Circuitry is coupled to the substrate within the housing. The circuitry comprises a laser diode and memory configured to store information related to the TO package. Electrical connectors are coupled to the substrate at the opposite side to the circuitry. At least one of the electrical connectors is electrically connected to the memory. A disclosed method includes assembling a TO package, testing the TO package, storing results of the testing in memory, and making the information stored in the memory, including the results of the testing, available to a device external to the TO package. The TO package includes a laser diode and memory configured to store information related to the TO package.

Abstract: A light output control device for laser light sources for respective RGB colors includes, for each of RGB, three sets, each including: a semiconductor laser for one of the colors; light output detection unit for detecting a light output from the semiconductor laser; light output adjustment unit for updating a light output target value; light output control unit for controlling the semiconductor laser based on the updated light output target value; and division unit for dividing the light output by an output from the light output adjustment unit to obtain a ratio of the rising of the light output, and includes rising determination unit for determining, based on results obtained by the respective division unit, a semiconductor laser with a slowest rising and outputs light output adjustment values for the respective colors. The light output adjustment unit update their respective light output target values based on the light output adjustment values.

Abstract: A method is provided to calibrate a monitor photodiode that measures the optical output power generated by an optoelectronic transceiver module that includes a burst mode laser diode. The method includes disabling the power control loop that controls an average optical output power generated by the laser diode during a laser burst. A series of logic zero signals is applied to a data input of the transceiver module and the logic zero level of the optical signal generated by the burst mode laser diode while applying the series of logic zero signals is measured. The logic zero bias level applied to the laser diode is adjusted until the measured logic zero level of the optical signal reaches a first desired value. While maintaining the optical signal at the first desired value, a first value of a current generated by the monitor photodiode in response to optical energy received from a back facet of the laser diode is stored.

Abstract: A feedback control module for stabilizing a carrier-envelope phase of an output of a laser oscillator system comprises a first photodetector, a second photodetector, a phase stabilizer, an optical modulator, and a thermal control element. The first photodetector may generate a first feedback signal corresponding to a first portion of a laser beam from an oscillator. The second photodetector may generate a second feedback signal corresponding to a second portion of the laser beam filtered by a low-pass filter. The phase stabilizer may divide the frequency of the first feedback signal by a factor and generate an error signal corresponding to the difference between the frequency-divided first feedback signal and the second feedback signal. The optical modulator may modulate the laser beam within the oscillator corresponding to the error signal. The thermal control unit may change the temperature of the oscillator corresponding to a signal operable to control the optical modulator.

Abstract: A automatic power control loop comprises a photo diode used for sensing a light intensity of a laser diode to generate a feedback current, a switch selector used for selecting one among a plurality of predetermined currents according to a control signal generated by a controller, a transducer used for transferring a current different between the feedback current and the selected predetermined current into a load voltage, a comparator used for comparing the load voltage with a reference voltage to generate a comparison signal, a counter used for counting a count value according to the comparison signal and the control signal, and a laser diode driver used for generating a corresponding bias current in response to the count value to drive the laser diode. Thereby, the bias current will be adjusted within an allowable range, so that the light source of the laser diode can maintain a constant light intensity.

Abstract: Embodiments of the present disclosure provide systems, devices, and methods for photodetection. For example, briefly described, in one embodiment among others, a sensor comprises an array of photodetectors, wherein the reflectance of each of the photodectors is a function of the number of photons incident on the respective photodetector; and an electrical insulator positioned between one of the photodetectors and another one of the photodetectors to reduce diffusion of electrons therebetween.

Abstract: A driver circuit for a semiconductor laser diode (LD) is disclosed, in which the driver circuit drives the LD in the differential mode and lowers the power consumption thereof. The driver circuit includes a differential unit to provide the modulation current to the LD, a voltage converter to provide a positive power supply to the differential unit, a detector to detect the common mode voltage of the differential outputs of the unit, and a comparing unit to control the voltage converter dynamically such that the output common mode voltage is set in a preset reference level.

Abstract: An assembly (10) that generates a laser beam (12) includes a voltage source (14), a gain medium (24A), a closed loop current regulator (22), and a controller (18). The gain medium (24A) generates the laser beam (12) when medium current flows through the gain medium (24A). The current regulator (22) regulates the medium current that flows through gain medium (24A) from the voltage source (14) independent of a voltage of the voltage source (14). The controller (18) directs a command input (20) to the current regulator (22) that is used to control the current regulator (22).

Abstract: A method and apparatus are disclosed for controlling bandwidth in a multi-portion laser system comprising a first line narrowed oscillator laser system portion providing a line narrowed seed pulse to an amplifier laser system portion, may comprise utilizing a timing difference curve defining a relationship between a first laser system operating parameter other than bandwidth and the timing difference and also a desired point on the curve defining a desired timing difference, wherein each unique operating point on the curve corresponds to a respective bandwidth value; determining an actual offset from the timing difference at the desired point on the curve to an actual operating point on the curve; determining an error between the actual offset and a desired offset corresponding to a desired bandwidth; modifying the firing differential timing to remove the error between the actual offset and the desired offset.

Abstract: According to aspects of an embodiment of the disclosed subject matter, a line narrowed high average power high pulse repetition laser micro-photolithography light source bandwidth control method and apparatus are disclosed which may comprise a bandwidth metrology module measuring the bandwidth of a laser output light pulse beam pulse produced by the light source and providing a bandwidth measurement; a bandwidth error signal generator receiving the bandwidth measurement and a bandwidth setpoint and providing a bandwidth error signal; an active bandwidth controller providing a fine bandwidth correction actuator signal and a coarse bandwidth correction actuator signal responsive to the bandwidth error. The fine bandwidth correction actuator and the coarse bandwidth correction actuator each may induce a respective modification of the light source behavior that reduces bandwidth error. The coarse and fine bandwidth correction actuators each may comprise a plurality of bandwidth correction actuators.

Abstract: One embodiment of the invention includes an optical system. The optical system includes an optical cavity comprising a plurality of reflectors. The optical system also includes optics configured to provide a first optical signal and a second optical signal into respective inputs of the optical cavity to be substantially concurrently resonated within the optical cavity. The first and second optical signals can have distinct wavelengths.

Abstract: A laser control method includes the steps of: using a laser control circuit which includes a constant current circuit that maintains a constant current flowing through a semiconductor laser element, and which includes an adder and a multiplier connected to a stage preceding the constant current circuit, and using detection means for calibration for detecting an applied laser output; calculating, on the basis of a detection signal output from the detection means, a reference bias value and a reference gain value for obtaining a specified laser output with respect to a specified input to the multiplier; inputting the reference bias value and the reference gain value to the adder and the multiplier, respectively; and controlling the applied laser output from the semiconductor laser element by performing calibration.

Abstract: The present invention relates to a method of measuring backward light, which is constructed for checking, prior to laser processing, backward light that propagates backward through an isolator included in a laser processing apparatus. The present invention also relates to a laser processing method and the like. A laser processing apparatus has an optical head provided with a laser light source part, light guide, and isolator. The optical head has an emitting optical system, irradiation optical system, and light collecting optical system. The method of measuring backward light uses a photodetector to detect, from reference light introduced from a measurement light source into the optical head, the power of an optical component that has passed through the isolator, while changing the position of the measurement light source.

Abstract: A semiconductor laser module includes a semiconductor laser section, a light selecting section, and an optical converting section. The semiconductor laser section includes a semiconductor laser substrate, a plurality of semiconductor laser elements mounted on the semiconductor laser substrate, and a first temperature adjusting element for adjusting temperature of the semiconductor laser elements. The light selecting section includes a light selecting element substrate and a light selecting element mounted on the light selecting element substrate and optically connected to the semiconductor laser elements, which selects laser light output from at least one of the semiconductor laser elements.

Abstract: To provide a semiconductor optical device which can restrain laser characteristics from being deteriorated by excitation in a substrate mode and can reduce the number of manufacturing steps. A semiconductor optical device comprises a first DBR layer, provided on a semiconductor substrate, having first and second semiconductor layers stacked alternately, a first cladding layer, an active layer, and a second cladding layer. The semiconductor substrate has a bandgap higher than that of the active layer. The first DBR layer is transparent to light having an emission wavelength, while the first and second semiconductor layers have respective refractive indices different from each other. Since the first DBR layer is thus provided between the semiconductor substrate and first cladding layer, the guided light reaching the lower end of the first cladding layer, if any, is reflected by the first DBR layer, whereby light can be restrained from leaking to the semiconductor substrate.

Abstract: The object is to measure the carrier envelope offset frequency of a mode-locked laser.

Abstract: An optical head includes a plurality of unit regions repeatedly arrayed in one direction. Each region is constituted by a light-emitting element which is driven by a current to emit light, a control transistor which is connected in parallel with the light-emitting element, and which receives gray-scale data that specifies a high gray-scale level for the light-emitting element so as to be turned off and which receives gray-scale data that specifies a low gray-scale level for the light-emitting element so as to be turned on, and a driving transistor which is connected in series with the light-emitting element to generate a current. In each of the plurality of unit regions, a thermal resistance between the light-emitting element formed in the unit region and the control transistor formed in the unit region is smaller than a thermal resistance between the light-emitting element and a control transistor formed in a unit region adjacent to the unit region.

Abstract: The invention provides a laser light detection circuit that prevents a peak output occurring when the circuit switches between the operation stop mode and the operation mode so as to prevent the breakdown or malfunction of the next-connected circuit. A laser light detection circuit has a differential amplifier that amplifies and outputs a signal corresponding to the intensity of laser light, a drive transistor having a base to which the output of the differential amplifier is applied, a second constant-current source connected to the emitter of the drive transistor, an output transistor having a base connected to the emitter of the drive transistor, a bypass transistor connected between the emitter of the drive transistor and the ground, and a control circuit. The control circuit forms a bypass current route from the second constant-current source to the ground through the bypass transistor by turning on the bypass transistor when the circuit switches from the operation stop mode to the operation mode.

Abstract: An optical transceiver module configured for longwave optical transmission is disclosed. Significantly, the transceiver module utilizes components formerly used only for shortwave optical transmission, thereby reducing new component production and device complexity. In one embodiment, the transceiver module includes a transmitter optical subassembly including a laser capable of producing an optical signal. A consolidated laser driver/post amplifier including a first bias current source provides a bias current to the laser for producing the optical signal. A means for amplifying the bias current provided to the laser by the first bias current source is also included as a separate component from the laser driver/post amplifier. The means for amplifying in one embodiment is a field-effect transistor that is operably connected to the laser driver/post amplifier and configured to provide an additional bias current to the laser diode such that sufficient lasing operation of the laser is realized.

Abstract: An optical transmitter is disclosed in which the wavelength deviation occurred at the turning on from the disabled state to the enabled state by the negating of the Tx_Disable command is suppressed. The optical transmitter includes a semiconductor laser diode (LD) and an automatic temperature controller (ATC) circuit to drive the thermo-electric cooler (TEC). When the transmitter receives the Tx_Disable to start up the operation of the LD, a pulsed signal is generated in synchronizing with the transition of the Tx_Disable signal to momentarily enhance the cooling capacity of the TEC in order to compensate the increase of the temperature of the LD by the self heating, which prevents the output wavelength of the transmitter from deviating.

Abstract: The output voltage of a cathode drive-type semiconductor laser driving circuit is set to a minimum, power consumption by a driving circuit portion is suppressed, and the heat that is generated by the optical head or the optical disc device is reduced. In addition to a conventional configuration, the semiconductor laser driving circuit of the invention measures the cathode voltage (Vout) of a semiconductor laser (1) and controls the anode voltage (Vld) such that the cathode voltage (Vout) becomes a predetermined level, and by doing so sets the output voltage of the semiconductor laser driving circuit to a predetermined level in order to curtail power consumption by the driving circuit and minimize the rise in temperature of the optical head or the optical disc device.

Abstract: A laser light source experiencing an EOL condition, which might otherwise cause an unscheduled shutdown, is instead operated in a diminished capacity in one or more predetermined or calculated increments. Operating in such diminished capacity continues until the laser system can undergo appropriate maintenance either during a regularly scheduled shutdown or a newly scheduled shutdown. In the meantime, the diminished capacity of the laser system is accommodated by the utilization tool, as appropriate.

Abstract: A semiconductor laser driver includes a light detection circuit to detect a quantity of light as a detected light emission intensity and output the detected light emission intensity to the control circuit, and a control circuit to control a light emission intensity for the semiconductor laser based on the detected light emission intensity and on a predetermined light emission intensity setting value. The light detection circuit includes a photoelectric conversion element to convert the quantity of light emitted from the semiconductor laser into an electrical current and output the converted electrical current, a current magnification setting circuit to amplify the electrical current output from the photoelectric conversion element to a predetermined amplified current at one of multiple different predetermined magnifications, a detection resistor to convert the amplified current output from the current magnification setting circuit into a voltage and output the voltage as the detected light emission intensity.

Abstract: A laser system is proposed that is configured to provide a pseudo-CW signal at room temperature. The system utilizes an array of pulsed lasers that are controlled (in terms of turning “on” and “off”) to provide, in combination, a quasi-CW output signal. The activation of each individual laser is controlled to turn “on” and “off” in a predefined sequence, where at least one laser is “on” at any given point in time. Thus, by combining the outputs from the plurality of pulsed lasers onto a single output signal path, the resultant output signal from the system will be a pseudo-CW signal (the amount of “ripple” present in the signal controlled by factors such as the number of individual lasers in the plurality of lasers, the duty cycle of each individual laser, etc.). The duty cycle of the individual lasers can be controlled to provide a high power output signal (higher duty cycle), or provide a high wall-plug efficiency of the system (lower duty cycle).

Abstract: The present patent application provides a low power consumption pump driving circuit including a laser cooling chip, a PMOS transistor, a NMOS transistor, a LC filter circuit, a laser, and a voltage sampling circuit. The pulse width modulating signal generated by the laser cooling chip and the control terminal of the PMOS transistor are connected to the gate of the PMOS transistor. The source of the PMOS transistor is connected to a power supply. The drain of the PMOS transistor is connected to the LC filter circuit. The other terminal of the LC filter circuit is connected to the anode of the laser. The cathode of the laser is connected to the drain of the NMOS transistor. The source of the NMOS transistor is connected to the ground. One terminal of the voltage sampling circuit is connected to the laser. The other terminal of the voltage sampling circuit is connected to the laser cooling chip.

Abstract: A laser driver circuit comprising an amplifier device with a plurality of switchable subamplifiers, which can be or are connected to an output for connection of a laser, ith an analog switching device for switching of analog input signals, a plurality of analog inputs for the analog input signals, a plurality of control inputs for receiving digital control signals, wherein each switchable subamplifier has a switching device for switching the amplification by one of the digital control signals, a digital switching device connected to an input of each switching device for the selectable connection of the input of the switching device of each switchable subamplifier to a control input. Whereby each switchable subamplifier has an analog input, which is connected to the analog switching device for the selectable switching of an analog input signal to the analog input.