Class / Patent application number | Description | Number of patent applications / Date published |
372380070 | Controlling current or voltage to laser | 30 |
20080198884 | Constant-current drive circuit - A voltage supplied from a power supply is boosted by a boosting circuit unit to generate a direct-current voltage, and the pulse-shape direct-current voltage is applied to LED while a constant-voltage control unit controls the direct-current voltage. The operation of LED is controlled by a control unit and a PWM unit. When the current is passed through LED, the constant-voltage control unit obtains information on the current passed through LED from a potential difference between both ends of a resistor, and on-and-off control of the voltage applied to LED from the boosting circuit unit is performed at a high frequency based on the information. Therefore, the voltage applied to LED can be controlled to keep the current passed through LED constant. | 08-21-2008 |
20080291957 | WAVELENGTH TUNABLE LASER APPARATUS AND WAVELENGTH CONTROL METHOD - Included are: a gain chip having a gain unit and a phase control region; a current supply for causing a positive current to flow to the phase control region; a voltage supply for applying a bias voltage to the phase control region; and a control unit for selectively driving the current supply or the voltage supply depending on a direction of the wavelength shift. The control unit drives the current supply when a laser wavelength is to be shifted to a shorter wavelength side from a wavelength with the current supply and the voltage supply being turned off, and drives the voltage supply when the laser wavelength is to be shifted to a longer wavelength side from a wavelength with the current supply and the voltage supply being turned off. | 11-27-2008 |
20090207871 | LASER OSCILLATOR APPARATUS AND POWER SUPPLY APPARATUS THEREFOR, AND CONTROL METHOD THEREFOR - A laser output power command determination value from a controller ( | 08-20-2009 |
20090213886 | CONTROL METHOD OF DISTRIBUTED BRAGG REFLECTION SEMICONDUCTOR LASER, AND IMAGE PROJECTING APPARATUS - A DBR semiconductor laser is controlled in an image projecting apparatus, which includes the DBR laser having a phase and DBR region, a light wavelength converting device for converting fundamental-wave light emitted from the DBR laser into second harmonic wave light, an optical deflector for scanning the second harmonic wave in a one or two-dimensional manner, and a modulating portion for modulating the DBR laser. Coefficient calculating and wavelength adjusting steps are performed within a non-drawing time. The coefficient calculating step calculates at least one coefficient in a relationship between a DBR current to be injected into the DBR region and a phase current to be injected into the phase region for continuously shifting the wavelength of the fundamental-wave light. The wavelength adjusting step changes DBR current injected into the DBR region and phase current injected into the phase region based on the relationship. | 08-27-2009 |
20090323745 | SEMICONDUCTOR LASER DRIVING CIRCUIT, LIGHT EMITTING DEVICE, AND DISK DRIVE - A semiconductor laser driving circuit has a circuit protection function at low temperature and includes a voltage current converter that converts an input voltage Vin, which is determined according to a desired light brightness of the semiconductor laser to be driven, into a current. A current limiter limits an output current of the voltage current converter to a specified current value or less. An output amplifier amplifies the output current of the voltage current converter and supplies the amplified current as a drive current to the semiconductor laser. A temperature detection circuit detects a low temperature state and, in the low temperature state, decreases the specified current value of the current limiter. | 12-31-2009 |
20100061414 | OPTICAL SEMICONDUCTOR DEVICE AND DRIVING METHOD THEREOF - Objects are achieved by an optical semiconductor device comprising: a structure | 03-11-2010 |
20100098123 | METHOD AND APPARATUS FOR LASER CONTROL IN A TWO CHAMBER GAS DISCHARGE LASER - A laser control system contains an oscillator gas chamber and an amplifier gas chamber. A first voltage input is operatively connected to deliver electrical pulses to a first pair of electrodes within the oscillator gas chamber and a second pair of electrodes within the amplifier gas chamber. An output of the gas chambers is an energy dose calculated by a trapezoidal window. A control circuit connects to the first voltage input for modifying the first voltage input. A feedback control loop communicates an output of the gas chambers to the control circuit for modifying the first voltage input. | 04-22-2010 |
20100098124 | METHOD AND APPARATUS FOR LASER CONTROL IN A TWO CHAMBER GAS DISCHARGE LASER - A laser control system contains an oscillator gas chamber and an amplifier gas chamber. A first voltage input is operatively connected to deliver electrical pulses to a first pair of electrodes within the oscillator gas chamber and a second pair of electrodes within the amplifier gas chamber. An output of the gas chambers is an energy dose calculated by a trapezoidal window. A control circuit connects to the first voltage input for modifying the first voltage input. A feedback control loop communicates an output of the gas chambers to the control circuit for modifying the first voltage input. | 04-22-2010 |
20100111123 | DRIVER CIRCUIT OF LIGHT-EMITTING ELEMENT - A driver circuit is provided which comprises a series-connected unit having a light-emitting element and a current limiting inductor directly connected to the light-emitting element, a regenerative diode which is connected in parallel to the series-connected unit and which regenerates energy stored in the current limiting inductor, a transistor which controls a current flowing through the light-emitting element and the current limiting inductor, and a controller which controls an operation of the transistor, wherein the controller controls the transistor according to a voltage value of a power supply applied to the light-emitting element. | 05-06-2010 |
20100166031 | LASER DIODE DRIVER ARCHITECTURES - Laser diode driver architectures are disclosed. Some example current drivers are described, including a current channel to provide an output current. The current channel includes a current mirror with emitter degeneration, a startup transistor coupled to the current mirror to generate a DC bias on the current mirror, a beta helper circuit coupled to the current mirror and the startup transistor, to maintain the DC bias on the current mirror, and a cutoff transistor coupled to an emitter terminal of a current mirror transistor and to a reference voltage, to selectively couple the emitter terminal to the reference voltage to conduct the pre-determined output current. The example current drivers also include an output stage coupled to the output of the current mirror and to an output device, wherein the output stage provides a current gain in response to the cutoff transistor coupling the emitter terminal to the reference voltage. | 07-01-2010 |
20110058581 | Measuring station for measuring vehicles - A measuring station for measuring vehicles has at least one laser source, which emits laser radiation ( | 03-10-2011 |
20110085575 | DIGITAL PULSE-WIDTH-MODULATION CONTROL OF A RADIO FREQUENCY POWER SUPPLY FOR PULSED LASER - 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. | 04-14-2011 |
20110085576 | SMART LINEAR PULSED LASER DIODE DRIVER, AND METHOD - 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. | 04-14-2011 |
20110122906 | HIGH PRECISION WAVELENGTH MEASUREMENT AND CONTROL OF A TUNABLE LASER - A tunable laser wavelength measurement system includes an interferometric wavelength tracking system that uses a combination of interferometric and wavelength reference measurements to directly measure the laser output wavelength, The measurement exhibits the following desirable error signal characteristics: directional information, continuity, low latency, absolute information, high accuracy, high precision, and little or no drift, A tunable laser wavelength control system additionally incorporates electronics to compare the measured laser wavelength to a desired wavelength or wavelength function, and to generate a feedback control signal to control the wavelength of the laser output based on the comparison. In one non-limiting example implementation, the desired wavelength function is repetitive. The difference between the desired wavelength function and the interferometrically-measured wavelength function is taken, and a successive approximation technique is employed to calculate and adjust a repetitive controlling signal to obtain the desired wavelength function. | 05-26-2011 |
20110228803 | VCSEL WITH INTEGRAL RESISTIVE REGION - In one embodiment, a VCSEL includes a plurality of semiconductor layers, an insulative region, a resistive region, and a remainder region. The semiconductor layers include a lower mirror, an active region, and an upper mirror. The active region is disposed over the lower mirror and includes a first lasing region. The upper mirror is disposed over the active region. The insulative region and the resistive region are integrally formed in the semiconductor layers. The remainder region includes the semiconductor layers except for the insulative region and the resistive region integrally formed in the semiconductor layers. The insulative region is disposed between the resistive region and the remainder region. | 09-22-2011 |
20110243168 | GAS LASER OSCILLATOR HAVING FUNCTION FOR JUDGING DISCHAGE INITIATION - A gas laser oscillator capable of initiating discharge, without applying excess voltage to a discharge tube, and correctly and rapidly judging the initiation of discharge. The oscillator has a laser power commanding part adapted to generate a laser power command including a pulse superimposed on a forefront of each step, a voltage applying part adapted to apply a voltage to a discharge tube based on the laser power command, a discharge tube voltage detecting part adapted to detect the discharge tube voltage, a discharge tube voltage monitoring part adapted to monitor the discharge tube voltage, and a discharge initiation judging part adapted to judge that the discharge is initiated when the difference, between a change rate of the monitored voltage and a change rate of the discharge tube voltage predetermined based on data obtained while the discharge is normally carried out, is smaller than a predetermined threshold. | 10-06-2011 |
20120002691 | SYSTEM AND METHOD FOR PROVIDING A SAFETY MECHANISM FOR A LASER-EMITTING DEVICE - This invention generally relates to systems and methods for providing a safety mechanism for a laser-emitting device, and more specifically, to providing a safety mechanism for a portable laser-emitting illumination device. A lock interface is provided that allows that user to input a unlock code to activate or deactivate the device. | 01-05-2012 |
20120189028 | Apparatus and Method for Driving Multiple Lasers - A laser device includes a plurality of lasers that includes a first laser and a second laser. The laser device further includes a drive circuit configured to apply a pulsed current to the first laser at a first phase. The drive circuit is further configured to apply the pulsed current to the second laser at a second phase. The first phase and the second phase are different. A total voltage provided to the plurality of lasers during a period between the first and second phases is substantially smaller than a sum of individual voltages provided to the plurality of lasers, respectively, during a pulse period of the pulsed current. | 07-26-2012 |
20120201261 | SYSTEM AND METHOD TO REGULATE HIGH CURRENT RADIATION SOURCES - Disclosed is a high current radiation system. The system includes a high current radiation source to generate radiation and an analog circuit to generate, based, at least in part, on an input signal representative of the present current level delivered to the high current radiation source and a user-controlled input representative of a desired current level, an output signal to control a current level to be delivered to the high current radiation source. The system further includes a current driver to control the current delivered to the high current radiation source based, at least in part, on the output signal of the analog circuit. | 08-09-2012 |
20120224598 | Polarity Independent Laser Monitor Diode Current Sensing Circuit For Optical Modules - 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. | 09-06-2012 |
20130051416 | APPARATUS AND METHOD FOR BALANCING COMBINED RF POWER- SUPPLIES FOR DRIVING A CO2 GAS-DISCHARGE LASER - Radio-frequency (RF) power supply apparatus for supplying RF power to discharge electrodes of a gas-discharge laser includes a plurality of amplifier modules each having an RF output. A power combining arrangement is provided for combining the amplifier module RF-outputs into a single combined RF-output connected to the discharge electrodes. A DC power supply is connectable to or disconnectable from each of the transistor amplifier modules, separately, to allow current drawn by any of the amplifier modules to be monitored by a single current sensor. | 02-28-2013 |
20130148680 | Circuit and Method for Limiting Current to Prevent Roll-Over in Laser Diodes - The present disclosure relates to an optical power monitoring circuit including an automatic power control (APC) loop and a microcontroller unit (MCU), and a method for monitoring the same. The APC loop comprises a laser diode (LD) and a feedback loop to maintain a laser optical power. The MCU is configured to (i) monitor a bias current using a current sense circuit, (ii) monitor a rate of change of the bias current with time, and (iii) adjust a target power of the APC loop. By monitoring the bias current and the rate of change, and comparing them against thresholds, the target power can be adjusted by the MCU, to prevent roll-over in the laser diode, damage to the laser, and/or a hard failure in the data links that use the laser. | 06-13-2013 |
20130308669 | LASER DIODE DRIVER CIRCUIT - A laser diode drive circuit includes a laser diode (LD), a modulation-current differential drive circuit, a bias-current differential drive circuit, a first inductance connected between an anode of the LD and a positive power source, a second inductance connected between a cathode of the LD and a negative-phase output terminal of the bias-current differential drive circuit, a first resistor connected to a connection point of the anode of the LD and the first inductance and connected to a negative-phase output terminal of the modulation-current differential drive circuit, and a second resistor connected to a connection point of the cathode of the LD and the second inductance and connected to a positive-phase output terminal of the modulation-current differential drive circuit, and a positive-phase output terminal of the bias-current differential drive circuit is connected to the connection point. | 11-21-2013 |
20130315272 | REGENERATIVE AMPLIFIER, LASER APPARATUS, AND EXTREME ULTRAVIOLET LIGHT GENERATION SYSTEM - A regenerative amplifier according to one aspect of this disclosure is used in combination with a laser device, and the regenerative amplifier may include: a pair of resonator mirrors constituting an optical resonator; a slab amplifier provided between the pair of the resonator mirrors for amplifying a laser beam with a predetermined wavelength outputted from the laser device; and an optical system disposed to configure a multipass optical path along which the laser beam is reciprocated inside the slab amplifier, the optical system transferring an optical image of the laser beam at a first position as an optical image of the laser beam at a second position. | 11-28-2013 |
20150146752 | LIGHT EMITTING DEVICE AND IMAGE DISPLAY APPARATUS - A light emitting device includes: a light emitting element; and a temperature variable resistive element which is connected to the light emitting element in parallel and is provided so that heat of the light emitting element can be conducted, wherein the temperature variable resistive element has a characteristic in which a resistance value decreases as a temperature increases. | 05-28-2015 |
20150146753 | LIGHT EMITTING DEVICE AND IMAGE DISPLAY APPARATUS - A light emitting device includes: a light emitting element; and a light variable resistive element which is connected to the light emitting element in parallel and is provided at a position which is irradiated with light emitted from the light emitting element, wherein the light variable resistive element has a characteristic in which a resistance value decreases as an amount of irradiation light increases. | 05-28-2015 |
20150146754 | Control Apparatus for Driving a Laser Diode - A control apparatus for driving a laser diode comprises an output connection for connecting the laser diode, a regulation device for generating an output signal, a detector device which is designed to determine a regulation variable when the regulation device provides the output signal and the laser diode is connected to the output connection. The control apparatus furthermore comprises a computer device for providing a control signal for the regulation device, wherein the computer device provides the control signal independently of the regulation variable. The regulation device is designed in such a way that it generates a level for the output signal depending on the control signal and the determined regulation variable. | 05-28-2015 |
20160129513 | LASER APPARATUS WITH CAPACITOR DISPOSED IN VICINITY OF LASER DIODE - A laser assembly is disclosed. The laser assembly includes a carrier for mounting a semiconductor laser diode (LD) and a capacitor thereon. The carrier provides, in a top surface thereof, a metal pattern having a die area for mounting the LD through a brazing material, a mounting area, and an auxiliary area for absorbing a surplus brazing material. The capacitor is mounted on the mounting area closer to the LD through another brazing material. | 05-12-2016 |
20160149376 | CURRENT DRIVER FOR DIODE LASER SYSTEM - An architecture for current driver circuitry for diode laser systems is contemplated whereby the circuitry is both modular and minimally complex with respect to the number of components and connections. | 05-26-2016 |
20190148905 | GAS LASER DEVICE | 05-16-2019 |