Abstract: An optical assembly (OSA) that installs a semiconductor optical device mounted on a thermo-electric controller (TEC) is disclosed. The TEC in the upper plate thereof is mechanically connected to the housing, or to the block stiffly fixed to the housing by a bridge made of stiff material. The bridge preferably extends along the optical axis to show enhanced durability against the impact caused by an external ferrule abutting against the receptacle of the OSA.

Abstract: An optical transmitter is disclosed having a temperature stabilization system for an optical filter for maintaining constant the frequency response of the filter. The filter is mounted within a housing having a substantially higher thermal conductivity. The housing may include a copper-tungsten alloy and extend along the optical axis of the filter. The housing is in thermal contact with a thermo-electric cooler (TEC) and a temperature sensor. The TEC and temperature sensor are electrically coupled to a controller which adjusts the temperature of the TEC according to the output of the temperature sensor.

Abstract: A method for controlling wavelengths of a multi-path laser is provided. The method includes: obtaining a difference between an actual output wavelength and a target output wavelength of each laser (S601); obtaining a corrected control amount of a temperature controller of each laser by decoupling calculation according to the difference (S602); and determining a die temperature of each laser according to the corrected control amount of the temperature controller (S603). A system for controlling wavelengths of a multi-path laser includes a multi-path laser (10), a difference module (12), a decoupling module (14), and a temperature control module (16).

Abstract: A digital image projector includes a light assembly configured to project light along a light path from at least one laser array light source, the projected light having an overlapping far field illumination in a far field illumination portion of the light path; a temporally varying optical phase shifting device configured to be in the light path; an optical integrator configured to be in the light path; a spatial light modulator located downstream of the temporally varying optical phase shifting device and the optical integrator in the light path, the spatial light modulator configured to be located in the far field illumination portion of the light path; and projection optics located downstream of the spatial light modulator in the light path, the projection optics configured to direct substantially speckle free light from the spatial light modulator toward a display surface.

Abstract: Provided is a semiconductor laser chip improved more in heat dissipation performance. This semiconductor laser chip includes a substrate, which has a front surface and a rear surface, nitride semiconductor layers, which are formed on the front surface of the substrate, an optical waveguide (ridge portion), which is formed in the nitride semiconductor layers, an n-side electrode, which is formed on the rear surface of the substrate, and notched portions, which are formed in regions that include the substrate to run along the optical waveguide (ridge portion). The notched portions have notched surfaces on which a metal layer connected to the n-side electrode is formed.

Abstract: Various embodiments of a multi-laser system are disclosed. In some embodiments, the multi-laser system includes a plurality of lasers, a plurality of laser beams, a beam positioning system, a thermally stable enclosure, and a temperature controller. The thermally stable enclosure is substantially made of a material with high thermal conductivity such as at least 5 W/(m K). The thermally stable enclosure can help maintain alignment of the laser beams to a target object over a range of ambient temperatures.

Abstract: A laser diode package includes a laser diode, a cooler, and a metallization layer. The laser diode is used for converting electrical energy to optical energy. The cooler receives and routes a coolant from a cooling source via internal channels. The cooler includes a plurality of ceramic sheets and a highly thermally-conductive sheet. The ceramic sheets are fused together and the thermally-conductive sheet is attached to a top ceramic sheet of the plurality of ceramic sheets. The metallization layer has at least a portion on the thermally-conductive sheet. The portion is electrically coupled to the laser diode for conducting the electrical energy to the laser diode.

Abstract: An apparatus comprising a laser transmitter having a first side and a second side, a filter coupled to the first side, a detector coupled to the second side, and a temperature controller coupled to the laser transmitter and the detector. Also disclosed is an apparatus comprising at least one processor configured to implement a method comprising receiving a photocurrent of a backward light from a laser, determining a wavelength shift offset between a wavelength of the output light and a filter transmission peak, and adjusting a temperature of the laser to substantially reduce the wavelength shift and align the wavelength of the output light with the filter transmission peak.

Abstract: An integrated, low profile, high power laser light emission device is disclosed. The integrated laser light emission device provides uniform heat dissipation, as well as uniform pumping of the laser gain medium without the need for a pumping cavity. The laser system includes a pump diode array that can be mounted directly to a laser gain medium without intervening correcting optics hardware. Heat generated by the laser light emission device is cooled by a single cooling system. In the laser device, a pump diode array is preferably a Vertical-Cavity Surface-Emitting Laser (VCSEL) array. VCSEL arrays are mounted on the laser gain crystal by a metal cavity frame or metal stilts. The slightly elevated mounting of the VCSEL's enables increased cooling and maximizing the quantity of VCSEL's on the laser gain medium in order to achieve highly efficient and high power laser light output.

Abstract: A laser diode array having a plurality of diode bars bonded by a hard solder to expansion matched spacers and mounted on a gas or liquid cooled heatsink. The spacers are formed of a material such as copper/diamond composite material having a thermal expansion that closely matches that of the laser bars.

Abstract: A compact mid-IR laser device utilizes a quantum cascade laser to provide mid-IR frequencies suitable for use in molecular detection by signature absorption spectra. The compact nature of the device is obtained owing to an efficient heat transfer structure, the use of a small diameter aspheric lens and a monolithic assembly structure to hold the optical elements in a fixed position relative to one another. The compact housing size may be approximately 20 cm×20 cm×20 cm or less. Efficient heat transfer is achieved using a thermoelectric cooler TEC combined with a high thermal conductivity heat spreader onto which the quantum cascade laser is thermally coupled. The heat spreader not only serves to dissipate heat and conduct same to the TEC, but also serves as an optical platform to secure the optical elements within the housing in a fixed relationship relative on one another.

Abstract: A high power source of electro-magnetic radiation having a multi-purpose housing is disclosed. The multi-purpose housing includes an interior filled with a material forming at least a light source and further comprising a reflector which can envelope a laser rod surrounded by light sources for providing light excitation to the laser rod. A material defining outer surfaces of the light sources extends out to and defines outer surfaces of the reflector. A high-reflectivity coating is disposed over an outer surface of the reflector, as is a protective coating. Also disposed over an outer surface of the reflector can be an optional heat sink, with cooling being performed by an optional arrangement of forced-air traveling over the heat sink. The light sources may be light source pumps, and the high-reflectivity coating may be formed to envelop the reflector.

Abstract: A laser arrangement has at least one laser diode apparatus with a side surface which laterally limits the laser diode apparatus. The laser arrangement has a plurality of active regions arranged laterally side by side and configured to generate radiation. The laser diode apparatus is arranged on a mount. The distance between the side surface and an edge which laterally limits the mount on the part of the side surface is shorter than the distance between the side surface and the active region closest to the side surface. Additionally or alternatively, the distance between the side surface and the edge is shorter than one of the distances between two adjacent active regions of the laser diode apparatus.

Abstract: A light source mode alignment device and method and a passive optical network system are provided. The device includes a laser and a temperature control unit connected to each other and further includes a signal processing unit. The laser converts an incident light into a current signal. The current signal is amplified and converted into a voltage signal via a transimpedance amplifier. Together with a modulation signal generated by the signal processing unit, the voltage signal adjusts a bias voltage of the temperature control unit.

Abstract: Electrophotographic print system, comprising a photosensitive medium, and a laser array being provided with a plurality of laser diodes arranged to emit light onto the photosensitive medium for varying an electrical potential on a surface of the photosensitive medium, and a plurality of heat dissipation diodes, each heat dissipation diode being arranged in proximity to a corresponding laser diode, wherein each laser diode and the corresponding heat dissipation diode are coupled to a common drive circuit and are arranged in opposite current flow directions with respect to each other, so that in use the current flows either through the laser diode or through the heat dissipation diode depending on the current flow direction in the drive circuit.

Abstract: An optoelectronic device includes a header having a plurality of pins extending therethrough, a thermo-electric cooling device mounted adjacent to a side of the header and an optoelectronic assembly mounted on the thermo-electric cooling device. The optoelectronic assembly includes a light emitting device operable to emit an optical signal in response to an electric signal received by at least one of the plurality of pins, and a lens assembly operable to receive at least some of the light emitted by the light emitting device, the lens assembly having a lens. A cap substantially encloses the thermo-electric cooling device and the optoelectronic assembly. The cap has a window operable to transmit light emitted by the optoelectronic assembly. The lens is the only optical component in the lens assembly.

Abstract: A monolithic pumped laser cavity design is disclosed. Elements of the laser cavity, such as gain material, Q-switch, reflector, and outcoupler, are contact bonded together with a thermally conductive epoxy. The assembly is then operatively coupled to a heat sink (e.g., by mechanical or chemical means). The assembly is potted in thermally conductive potting material. The stacked elements or a subset thereof may be bonded to heat sink mounts and/or face cooling layers. In this fashion, various elements can be easily assembled and bonded together to provide the desired combination of laser energy, pulse width, and repetition frequency. The thermally conductive potting material provides structural integrity, as well as thermal management by extracting heat from the encased assembly to the heat sink. The optional heat sink mounts and face cooling operate to further extract heat and reduce thermal loading. Outcoupling to fiber may also be provided.

Abstract: A highly portable, high-powered infrared laser source is produced by intermittent operation of a quantum cascade laser power regulated to a predetermined operating range that permits passive cooling. The regulation process may boost battery voltage allowing the use of more compact, low-voltage batteries.

Abstract: A method and apparatus for controlling a wavelength tuning of an optical source in an optical communication system. An operating temperature of an optical source is controlled and monitored to shorten a wavelength tuning time of the optical source generated in an optical source generator. When the current operating temperature reaches a final target temperature, an operating current is supplied to the optical source generator, and transmission of the operating current to the optical source generator is controlled and monitored. When the operating current reaches a final operating current, the wavelength tuning of the optical source is terminated. The operating temperature is adjusted by distinguishing between a smaller amount of temperature change and a larger amount of temperature change to prevent oscillation at the point of reaching the final target temperature, thereby minimizing the time taken for the output wavelength tuning.

Abstract: 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.

Abstract: A laser module includes a semiconductor laser, an output optical system provided on an optical output side of the semiconductor laser, a temperature detecting element that detects a temperature of the output optical system; and an output controller that calculates a drive current to set an optical output intensity of the laser module at a desired value on the basis of temperature information obtained by the temperature detecting element, and outputs the drive current to the semiconductor laser.

Abstract: Various embodiments of a multi-laser system are disclosed. In some embodiments, the multi-laser system includes a plurality of lasers, a plurality of laser beams, a beam positioning system, beam focusing optics, a thermally stable enclosure and a temperature controller. The thermally stable enclosure is configured to thermally and mechanically couple to a flow cell. The thermally stable enclosure substantially comprises a material with high thermal conductivity. The thermally stable enclosure can have a relatively small volume.

Abstract: A high power laser source comprises at least a bar of laser diodes with a first coefficient of thermal expansion (CTEbar), a submount onto which said laser bar is affixed with a second coefficient of thermal expansion (CTEsub), and a cooler onto which said submount is affixed with a third coefficient of thermal expansion (CTEcool). The submount/cooling assembly exhibits an effective fourth coefficient of expansion (CTEeff). According to the invention, mechanical stress exerted to the laser bar improves reliability and optical performance. To effect this, CTEeff must differ from CTEbar, CTEeff?CTEbar. Preferably, CTEeff should differ by a predetermined amount from CTEbar. The difference is achieved in two ways: either by selecting CTEsub>CTEbar and CTEsub?CTEcool, or by selecting CTEsub<CTEbar and CTEsub<CTEcool. Thereby, all coefficients must be selected such that CTEeff differs from CTEbar: CTEeff?CTEbar, preferably by a percentage of 5% or by a predetermined amount of +/?3-4×10?7K?1.

Abstract: A semiconductor laser system includes a diode laser tile. The diode laser tile includes a mounting fixture having a first side and a second side opposing the first side and an array of semiconductor laser pumps coupled to the first side of the mounting fixture. The semiconductor laser system also includes an electrical pulse generator thermally coupled to the diode bar and a cooling member thermally coupled to the diode bar and the electrical pulse generator.

Abstract: A system for controlling optical-power stability of emitting laser diodes (204), the laser diodes exhibiting temperature changes at the laser diode junctions (312), the temperature changes are predicted according to the laser diodes duty cycle. The system includes, a laser diodes arranged to emit light on a target (14); a data stream analyzer (408) configured to receive incoming data stream (324) analyze the data and produce an image data occurrence factor of larger than zero values (424) representing the data in the incoming data stream (324); and an optical power stabilizer (412) configured to control current intensity (428) applied on a laser diode according to the image data occurrence factor (424).

Abstract: An optical transmission control circuit includes: an analog input section which receives optical transmission states as an analog values; an A/D conversion section which converts the analog values into digital values; a value storage section which stores maximum value of the digital values provided by the A/D conversion section; an output register which outputs a value to a host apparatus; and a control section which controls the maximum value storage section to store the maximum value of the digital values therein and controls the output register to output the maximum value to the host apparatus.

Abstract: A semiconductor laser beam device, comprising a stem type package having a base part and a heat sink part, wherein the heat sink part is cylindrically formed so as to be concentric to the base part, a groove is formed along the axial direction of the heat sink part, and a semiconductor laser beam element is disposed at the bottom part of the inner wall surfaces of the groove whereby the radiating capability of the semiconductor laser beam device can be increased by increasing the volume of the heat sink part, and the element can be protected by the groove.

Abstract: According to one embodiment, the present application includes a tunable laser configured in a small package. The tunable laser includes a housing with a volume formed by exterior walls. An electrical input interface is positioned at the first end of the housing and configured to receive an information-containing electrical signal. An optical output interface is positioned at the second end of the housing and configured to transmit a continuous wave optical beam. A tunable semiconductor laser is positioned in the interior space and operable to emit a laser beam having a selectable wavelength. A focusing lens assembly is positioned in the interior space along an optical path of the laser beam to operatively couple the laser beam to the optical output interface.

Abstract: The present invention relates to a semiconductor laser apparatus having a structure for preventing the corrosion of a refrigerant flow path in a heat sink and for cooling a semiconductor laser array stably over a long period of time. The semiconductor laser apparatus comprises a semiconductor laser stack in which a plurality of semiconductor laser units are stacked, a refrigerant supplier, a piping for connecting these components, and a refrigerant flowing through these components. The refrigerant supplier supplies the refrigerant to the semiconductor laser stack. The refrigerant is comprised of fluorocarbon. Each of the semiconductor laser units is constituted by a pair of a semiconductor laser array and a heat sink. The heat sink has a refrigerant flow path.

Abstract: A laser module (1) with at least two laser units (3) are adjusted such that the emitted beams of the laser units (3) converge. The laser units (3) exhibit cooling channels (5) that are provided with a cooling medium. At least one of the laser units has a curved adjustment surface (10) which his mounted to a facing mounting surface (9) of a mounting unit (2) such that a cooling channel opening in the adjustment surface (9) is located opposite an additional cooling channel opening in the mounting surface (10).

Abstract: Alerts, such as laser driver current alarms, are triggered in an optoelectronic device based on dynamic digital diagnostics, such as operating temperature. Optoelectronic devices may execute microcode structured to represent a formulaic relation between a first parameter (e.g., temperature) and an indicator value for a second parameter (e.g., laser driver current). The microcode may further be structured to cause the optoelectronic device to access the first parameter, calculate an indicator value for the second parameter based on the accessed first parameter using the formulaic relation, access the second parameter, and compare the indicator value with the second parameter to determine whether to trigger an alert. If the second parameter exceeds the indicator value, the alert may be triggered, and may be indicative of potentially imminent optoelectronic device failure.

Abstract: In a semiconductor device where a semiconductor element having an asymmetric temperature distribution during an operation is mounted, inner leads on the right and left ends have asymmetric lengths, so that the right and left regions of a semiconductor element mounting part have different sizes. The semiconductor element is mounted so as to have a high-temperature region side in a wide region of the mounting part, and the inner leads are wire bonded at the center to the wide region of the mounting part. It is thus possible to provide a small semiconductor device in which a long semiconductor element is mounted with heat dissipation.

Abstract: A compact mid-IR laser device utilizes a quantum cascade laser to provide mid-IR frequencies suitable for use in molecular detection by signature absorption spectra. The compact nature of the device is obtained owing to an efficient heat transfer structure, the use of a small diameter aspheric lens and a monolithic assembly structure to hold the optical elements in a fixed position relative to one another. The compact housing size may be approximately 20 cm×20 cm×20 cm or less. Efficient heat transfer is achieved using a thermoelectric cooler TEC combined with a high thermal conductivity heat spreader onto which the quantum cascade laser is thermally coupled. The heat spreader not only serves to dissipate heat and conduct same to the TEC, but also serves as an optical platform to secure the optical elements within the housing in a fixed relationship relative on one another.

Abstract: The light sources according to the present invention include a laser oscillator including a semiconductor laser, a drive circuit for the semiconductor laser, an ACC circuit, an APC circuit, and a switch, and a starting drive current storage device, and is controlled in such a manner that the driving current at the start of the laser driving be always constant, and after the start of the lighting, it is switched to the APC operation to carry out the power control of the laser light output.

Abstract: Current may be passed through an n-doped semiconductor region, a recessed metal semiconductor alloy portion, and a p-doped semiconductor region so that the diffusion of majority charge carriers in the doped semiconductor regions transfers heat from or into the semiconductor waveguide through Peltier-Seebeck effect. Further, a temperature control device may be configured to include a metal semiconductor alloy region located in proximity to an optoelectronic device, a first semiconductor region having a p-type doping, and a second semiconductor region having an n-type doping. The temperature of the optoelectronic device may thus be controlled to stabilize the performance of the optoelectronic device.

Abstract: The controller 170 controls the output power of the semiconductor laser device 100a depending on the temperature of the semiconductor laser device 100a acquired by the temperature sensor 130. The controller 170 references the correspondence table 510 when the sensor temperature Ts is obtained, obtains the output power PWs corresponding to the sensor temperature Ts, and controls the power supply driving circuit 150a so that the output power per unit time of the semiconductor laser device 100a will be the output power PWs. Thus increase in temperature of the semiconductor laser device is able to be prevented through reducing the output power by controlling the amount of power supplied to the semiconductor laser device.

Abstract: The present invention relates to an external-cavity laser module comprising a thermoelectric cooler (TEC) including an upper carrier plate having an upper surface, said TEC being configured to stabilize the temperature of the upper surface at a substantially constant temperature. The laser module further comprises a laser assembly mounted on an optical bench, which is in thermal coupling with said upper surface, said laser assembly comprising a gain medium for emitting an optical beam into the external cavity and an end mirror.

Abstract: In the present invention, the extremely complicated setting and control and an extremely expensive optical component (wavelength locker) are not required, and optical output wavelength and optical output power can simply be set and controlled at a moderate price. At least one value for determining a dependence of the optical output wavelength on drive current and device temperature and at least one value for determining a dependence of the optical output power on drive current and device temperature in a light emitting device constituting first means 1 for emitting light are stored in fourth means 4.

Abstract: Provided is a multiple distributed feedback laser device. The laser device includes an active layer, a first diffraction grating, and a second diffraction grating. The substrate includes a first distributed feedback region, a modulation region, and a second distributed feedback region. The first diffraction grating is coupled to the active layer in the first distributed feedback region. The second diffraction grating is coupled to the active layer in the second distributed feedback region. In addition, the laser device includes a first micro heater and a second micro heater. The first micro heater supplies heat to the first diffraction grating. The second micro heater supplies heat to the second diffraction grating. The first micro heater and the second micro heater are controlled independently from each other.

Abstract: A laser diode array is formed on a heat sink having an insulating layer in which a plurality of grooves is formed through the ceramic layer and to or into the heat sink. A laser diode stack is soldered to the ceramic layer.

Abstract: A laser diode package (10) according to the present invention is tolerant of short-circuit and open-circuit failures. The laser diode package (10) includes a laser diode bar (12), a forward-biased diode (14), a heat sink (18), and a lid (16) which may have fusible links (86). The laser diode bar (12) and the forward-biased diode (14) are electrically connected in parallel between the heat sink (18) and the lid (16). The emitting region of the laser diode bar (12) is aligned to emit radiation away from the forward-biased diode (14). Several packages can be stacked together to form a laser diode array (42). The forward-biased diode (14) allows current to pass through it when an open-circuit failure has occurred in the corresponding laser diode bar (12), thus preventing an open-circuit failure from completely disabling the array (42).

Abstract: A VCSEL with undoped top mirror. The VCSEL is formed from an epitaxial structure deposited on a substrate. A doped bottom mirror is formed on the substrate. An active layer that includes quantum wells is formed on the bottom mirror. A periodically doped conduction layer is formed on the active layer. The periodically doped conduction layer is heavily doped at locations where the optical energy is at a minimum when the VCSEL is in operation. A current aperture is used between the conduction layer and the active region. An undoped top mirror is formed on the heavily doped conduction layer.

Abstract: There is provided a light-emitting module which suppresses wavelength drift. A light-emitting module according to the invention includes a stem and a cap fixed to the upper surface of the stem. A thermo-electric cooler is mounted on the stem and a base is mounted on the thermo-electric cooler. A laser diode is mounted on one side of the base. A thermistor that measures the temperature of the laser diode is mounted on another side. The other side includes an overhung portion that blocks radiant heat transmitting from the cap toward the thermistor.

Abstract: An optical output controller includes a wavelength conversion device operable to change the wavelength of pumped laser light; a heating/cooling unit operable to control the temperature of the wavelength conversion device; a temperature detector which detects the temperature of the wavelength conversion device; a temperature controller operable to control the heating/cooling unit such that the detected temperature corresponds to a target temperature; an optical output detector operable to detect the optical output from the wavelength conversion device; an optical-output maximization controller operable to determine a temperature at which the optical output is maximized according to the optical output detected by the optical output detector and from the detected temperature detected by the temperature detector and, further, outputs the temperature difference between the determined temperature and the detected temperature; and an adder which adds the temperature difference outputted from the optical-output maxim

Abstract: A heat spreader structure includes a high power laser with an epi side and an emitting facet. A vapor chamber includes a housing defining an inner vapor cavity and a wick positioned in the vapor cavity to define an evaporation area on one side of the cavity, a condensation area on an opposite side of the cavity, and fluid communication between the condensation area and the evaporation area. A space defined between the evaporation area and the condensation area. The wick includes a porous powder sintered to inner surfaces of the sealed cavity to hold the porous powder in position. The epi side of the laser is coupled to the one side of the vapor chamber and heat removal mechanism is coupled to the opposite side of the cavity.

Abstract: The laser device (22) is formed by a stack of laser diodes (4) arranged on plates (6) formed of a material that is electrically conductive and a good heat conductor. In order to obtain a high level of heat evacuation efficiency towards the cooling body (10) and to prevent electric short-circuiting problems, each plate has at the bottom end (24) thereof, an electrically insulating layer deposited on the surface thereof prior to being fixed to the cooling body by a securing material (26) that is preferably a good heat conductor, formed in particular by a braze layer. According to the invention, the insulating layer covers the end face of each plate and also goes up along the lateral faces of the latter over a certain height. The securing material is arranged under the end of the plate and also partially covers the insulating layer along the lateral faces of the plate.

Abstract: An extremely versatile diode laser assembly is provided, the assembly comprised of a plurality of diode laser subassemblies mounted to a stepped cooling block. The stepped cooling block allows the fabrication of a close packed and compact assembly in which individual diode laser subassembly output beams do not interfere with one another.

Abstract: An optical communications circuit has a communications light signal source and a heat pump coupled to cool the signal source. A controller monitors a current and a temperature of the signal source, and regulates the temperature. The controller updates a heat pump control limit parameter for the heat pump, based on the monitored current. Other embodiments are also described and claimed.

Abstract: A light source and the method for operating the same are disclosed. The light source includes first and second lasers, and first and second wavelength control assemblies. The lasers emit first and second light beams, respectively, at wavelengths that are determined by first and second wavelength control signals. First and second beam splitters split the first and second light beams, respectively, to create first and second sampling light beams. The first and second wavelength control assemblies receive sampling light beams and generate the first and second wavelength control signals such that the wavelengths of the first and second light beams differ by no more than a predetermined amount. The first and second wavelength control assemblies each include an absorption cell having a gas that has an optical absorption that varies with the wavelength of the first and second sampling light beams at wavelengths around the output wavelength of the light source.

Abstract: A method is disclosed for varying a pulse repetition rate of a passively q-switched laser while maintaining other characteristics of the laser radiation. The laser is optically pumped with a sequence of pump pulses which includes alterations between non-zero power levels and is characterized by two adjustable parameters. By simultaneously changing the adjustable parameters, the pulse repetition rate of the laser can be changed while maintaining the laser pulse energy, divergence of the pulsed laser radiation, and optical spectrum of the pulsed laser radiation at constant levels. In one embodiment, the sequence of pump pulses includes pump power offset which magnitude and/or duration is adjusted when the laser repetition rate is changed.