A system includes: an optical source including a plurality of optical oscillators; a spectral analysis apparatus; and a controller. Each optical oscillator is configured to produce a light beam. The controller is configured to: determine, based on data from the spectral analysis apparatus, whether the spectral property of the light beam of one of the optical oscillators is different than the spectral property of the light beam of at least another of the plurality of optical oscillators. If the spectral property of the light beam of the first one of the optical oscillators is different than the spectral property of the light beam of another of the optical oscillators, the controller is configured to adjust the spectral property of the light beam of the first one of the optical oscillators or of the light beam of at least one other of the optical oscillators.

Light amplification devices using coupled multi-core optical fibers have a figure of merit that temporally varies, which makes it difficult to perform performance evaluation and to build a light transmission system using the same. Accordingly, a light amplification device of the present invention comprises: a band control means that controls the wavelength band of a light carrier to generate a band control light; and a band control light amplification means that has a plurality of light amplification media through which the band control light propagates, wherein the band control light amplification means amplifies the band control light in a coupled state in which the light propagating through the plurality of light amplification media induces a crosstalk and wherein the band control means controls the wavelength band such that the band control light having propagated through the plurality of light amplification media has a reduced coherence.

An ultraviolet laser apparatus includes: a semiconductor laser that emits an excitation laser light; a fiber laser medium to which the excitation laser light enters from the semiconductor laser and that causes laser oscillation; and an external resonator that: converts a wavelength of a laser light oscillated in the fiber laser medium, and outputs an ultraviolet region continuous wave of at least 0.1W.

A control method for a line narrowed gas laser apparatus is a control method for a line narrowed gas laser apparatus configured to emit a pulse laser beam including a first wavelength component and a second wavelength component. The apparatus includes a laser chamber including a pair of electrodes, an optical resonator including an adjustment mechanism configured to adjust a parameter of an energy ratio of the first and second wavelength components, and a processor in which relation data indicating a relation of the parameter of the energy ratio with a control parameter of the adjustment mechanism is stored. The control method includes receiving a command value of the parameter of the energy ratio from an external device, and acquiring, based on the relation data, a value of the control parameter corresponding to the command value and controlling the adjustment mechanism based on the value of the control parameter.

A control method of a line narrowing gas laser device includes receiving a command of either a single-wavelength mode command or a multi-wavelength mode command from an external apparatus, and controlling the line narrowing gas laser device to generate pulse laser light in accordance with the command.

A narrowed-line gas laser apparatus includes a laser chamber that accommodates a pair of electrodes disposed so as to face each other, an output coupling mirror, and a line narrowing apparatus that forms an optical resonator along with the output coupling mirror, the line narrowing apparatus including an optical system having a first region and a second region on which a first portion and a second portion of a light beam that exits out of the laser chamber are incident, the first and second portions passing through different positions in a direction in which the pair of electrodes face each other, the optical system being configured to suppress an increase in the distance between the optical path axis of the first portion and the optical path axis of the second portion.

A medical laser system for outputting laser pulses includes at least one laser cavity configured to generate at least one laser pulse, a rotating mirror configured to receive and reflect the at least one laser pulse, a beam splitter configured to receive and reflect a portion of the at least one laser pulse received from the rotating mirror, an energy-sensing device configured to detect the portion of the at least one laser pulse, an energy measurement assembly configured to generate a feedback signal based on the portion of the at least one laser pulse detected by the energy-sensing device, and a controller configured to generate an electronic control pulse based on the feedback signal received from the energy measurement assembly to generate at least one adjusted laser pulse.

An exposure system according to an aspect of the present disclosure includes a laser apparatus emitting a pulse laser beam, an illumination optical system guiding the pulse laser beam to a reticle, a reticle stage moving the reticle, and a processor controlling emission of the pulse laser beam and movement of the reticle. The exposure system performs scanning exposure of a semiconductor substrate by irradiating the reticle with the pulse laser beam. The reticle has first and second regions. The processor instructs the laser apparatus about, based on proximity effect characteristics corresponding to the first and second regions, a value of a control parameter of the pulse laser beam corresponding to each region so that the laser apparatus emits the pulse laser beam with which a difference of the proximity effect characteristic of each region from a reference proximity effect characteristic is in an allowable range.

A medical laser system for outputting laser pulses includes at least one laser cavity configured to generate at least one laser pulse, a rotating mirror configured to receive and reflect the at least one laser pulse, a beam splitter configured to receive and reflect a portion of the at least one laser pulse received from the rotating mirror, an energy-sensing device configured to detect the portion of the at least one laser pulse, an energy measurement assembly configured to generate a measurement signal based on the portion of the at least one laser pulse detected by the energy-sensing device, and a controller. The controller may include a calibration module. The calibration module may be configured to generate at least one categorized calibration table, determine calibration parameters, interpolate the calibration parameters, and cause the at least one laser cavity to generate at least one calibrated laser pulse.

A medical laser system for outputting laser pulses includes at least one laser cavity, a rotating mirror, a user interface, and a controller. The controller is configured to receive at least one laser parameter associated with a laser pulse output by the system. The controller is configured to determine an average power level of the laser pulse based on the at least one laser parameter associated with the laser pulse. The controller is configured to determine a pulse width modulation (PWM) control signal based on at least one laser parameter. The controller is configured to generate the laser pulse based on the average power level and the PWM control signal, the laser pulse comprising at least one of a first shape, a second shape, or a third shape. Each of the first shape, the second shape, and the third shape of the laser pulse includes different pulse widths.