A laser system includes: A. a solid-state laser apparatus configured to output a pulse laser beam having light intensity distribution in a Gaussian shape that is rotationally symmetric about an optical path axis; B. an amplifier including a pair of discharge electrodes and configured to amplify the pulse laser beam in a discharge space between the pair of discharge electrodes; and C. a conversion optical system configured to convert the light intensity distribution of the pulse laser beam output from the amplifier into a top hat shape in each of a discharge direction of the pair of discharge electrodes and a direction orthogonal to the discharge direction.

Method and systems are disclosed for generating amplified output laser pulses with individually predefined pulse energies at individually predefined times at an output by providing a pulse sequence of input laser pulses having the same pulse energy and the same temporal pulse interval smaller than the temporal pulse interval between two adjacent output laser pulses, selecting the input laser pulses that arrive at the output at or about the predefined times, amplifying the selected input laser pulses with an optical amplifier, wherein at least one sacrificial laser pulse is inserted into the pulse sequence of the selected input laser pulses before the subsequent one of the two successive input laser pulses to be amplified, and reducing the pulse energies of the amplified input laser pulses to predefined pulse energies by time-controlled partial decoupling depending on their pulse intervals from the corresponding immediately preceding amplified input or sacrificial laser pulse.

A method for generating output laser pulses from input laser pulses includes causing the input laser pulses to temporally successively pass through an optical component with temperature-dependent power efficiency. The optical component is heated by the passing of the input laser pulses. The input laser pulses emerge from the optical component as output laser pulses. The method further includes calculating a current temperature or a current temperature difference of the optical component, or a temperature-dependent current parameter based on all preceding input laser pulses or output laser pulses that have contributed to the heating of the optical component, and setting a power of a current input laser pulse based on the calculated current temperature, or the calculated current temperature difference, or the calculated current parameter, so that an associated output laser pulse has a pulse energy that deviates from a predefined pulse energy by less than 5%.

Disclosed is a laser system including a source, for generating a source signal, and an optical amplifier system. The laser system includes a pulse selection or variation device configured to select or vary the source signal so as to form a main signal composed of one or more light pulses. The main signal is temporally variable in terms of rhythm and/or amplitude. The laser system is configured to inject the main signal and a secondary signal into the optical amplifier system. The secondary signal is varied on the basis of the temporal variation in terms of rhythm and/or amplitude of the main signal so as to stabilize the power stored in the optical amplifier system in a time-dependent manner, and the laser system is configured to spatially separate the amplified main signal from the amplified secondary signal.

An optical device may include a package having a first port for receiving signal light, a source for providing pump light, a combiner for combining the signal light and the pump light into combined light, a second port for sending the combined light, a third port for receiving amplified light, and a free-space optical system for filtering amplified signal light from the amplified light, and a fourth port for sending the amplified signal light. The free-space optical system may include beam shaping optics that enlarge a beam size of the amplified light prior to the filtering.

A laser device includes at least one amplification unit configured to amplify laser light emitted from a laser oscillator, and an amplification control unit configured to control the amplification unit. The amplification unit includes an incident-side optical adjustment unit including a wavefront adjustment unit configured to adjust a wavefront of the laser light and a first direction adjustment unit configured to adjust an optical axis thereof, an amplifier configured to amplify the laser light, an emission-side optical adjustment unit including a second direction adjustment unit configured to adjust an optical axis of the laser light, and a measurement unit configured to measure the laser light and acquire information on at least one of an optical axis, a wavefront and energy of the laser light. The amplification control unit controls the incident-side optical adjustment unit and/or the emission-side optical adjustment unit, based on a measurement result of the measurement unit.

Methods and laser systems are disclosed for generating amplified output laser pulses with individually specified pulse energies and/or pulse shapes at individually specified time points at an output by providing a first pulse sequence of input laser pulses with a same pulse energy and a same temporal pulse distance smaller than a temporal pulse distance between adjacent output laser pulses, selecting input laser pulses arriving at the output at or close to the specified time points to form a second pulse sequence of input laser pulses, coupling at least one sacrificial laser pulse (energy balance or temporal balance) into the second pulse sequence, amplifying the second pulse sequence of input laser pulses with the sacrificial laser pulse, and coupling out the amplified sacrificial laser pulse from the amplified second pulse sequence upstream of the output to obtain the amplified output laser pulses.

An apparatus includes an optical amplifier configured to receive an input optical signal and generate an amplified output optical signal. The optical amplifier includes multiple amplifier stages including at least a first amplifier stage and a second amplifier stage. The apparatus also includes a gain clamp configured to accumulate optical power from the first amplifier stage after an optical power level of the input optical signal drops and provide a first portion of the accumulated optical power to the first amplifier stage to clamp a gain applied by the first amplifier stage. The gain clamp is also configured to provide a second portion of the accumulated optical power to the second amplifier stage to adjust a gain applied by the second amplifier stage. The second amplifier stage is configured to amplify the second portion of the accumulated optical power.

Method and systems are disclosed for generating amplified output laser pulses with individually predefined pulse energies at individually predefined times at an output by providing a pulse sequence of input laser pulses having the same pulse energy and the same temporal pulse interval smaller than the temporal pulse interval between two adjacent output laser pulses, selecting the input laser pulses that arrive at the output at or about the predefined times, amplifying the selected input laser pulses with an optical amplifier, wherein at least one sacrificial laser pulse is inserted into the pulse sequence of the selected input laser pulses before the subsequent one of the two successive input laser pulses to be amplified, and reducing the pulse energies of the amplified input laser pulses to predefined pulse energies by time-controlled partial decoupling depending on their pulse intervals from the corresponding immediately preceding amplified input or sacrificial laser pulse.

A laser system includes: A. a solid-state laser apparatus configured to output a pulse laser beam having light intensity distribution in a Gaussian shape that is rotationally symmetric about an optical path axis; B. an amplifier including a pair of discharge electrodes and configured to amplify the pulse laser beam in a discharge space between the pair of discharge electrodes; and C. a conversion optical system configured to convert the light intensity distribution of the pulse laser beam output from the amplifier into a top hat shape in each of a discharge direction of the pair of discharge electrodes and a direction orthogonal to the discharge direction.