A beam shutter for a laser beam includes a main body, a magnetic field sensor, a holding arm having release and closure positions, a reflecting optical unit and a permanent magnet producing a magnetic field having reduced strength upon heating above a limit temperature. The magnet is closer to the sensor in the closure than the release position. A controller deactivates a laser light source at reduced magnetic field measured by the sensor, when passing a predefined strength and/or gradient magnetic field threshold. A laser arrangement includes a laser light source and beam shutter. The laser beam strikes the reflecting unit in the closure position. An operating method includes bringing the holding arm into closure position, operating the laser light source, measuring magnetic field strength and/or gradient using the sensor, deactivating the laser light source when the magnetic field drops and passes the predefined magnetic field threshold.

A fractional handpiece and systems thereof for skin treatment include a passively Q-switched laser assembly operatively connected to a pump laser source to receive a pump laser beam having a first wavelength and a beam splitting assembly operable to split a solid beam emitted by the passively Q-switched laser assembly and form an array of micro-beams across a segment of skin. The passively Q-switched laser assembly generates a high power sub-nanosecond pulsed laser beam having a second wavelength.

An optical system for increasing contrast of pulsed laser radiation includes a first polarization setting optical unit for setting an elliptical polarization state of the pulsed laser radiation, and a multipass cell having at least two opposing mirrors. The pulsed laser radiation passes the multipass cell with formation of a plurality of intermediate focus zones. The multipass cell is filled with a gas having an optical nonlinearity that causes an intensity-dependent rotation of an alignment of the elliptical polarization state of the pulsed laser radiation, such that the multipass cell outputs beam portions having differently aligned elliptical polarization states on account of the intensity-dependent rotation. The optical system further includes an optical beam splitting system for splitting the beam portions having differently aligned elliptical polarization states.

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. Various embodiments of an optical system for directing light for optical measurements such laser-induced fluorescence and spectroscopic analysis are disclosed. In some embodiments, the optical system includes a thermally conductive housing and a thermoelectric controller, a plurality of optical fibers, and one or more optical elements to direct light emitted by the optical fibers to illuminate a flow cell. The housing is configured to attach to a flow cell.

An extended optical pulse stretcher is provided that combines confocal pulse stretchers in combination to produce, for example, 4 reflections, 4 reflections, 12 reflections, and 12 reflections per optical circuit configuration. The inclusion of the combination of different mirror separations and delay path lengths can result in very long pulse stretching, long optical delays, and minimal efficiency losses. Also, in the extended optical pulse stretcher, at least a beam splitter can be positioned relative to the center of curvature of the mirrors to “flatten” each of the circuits to enable the beam to propagate in the same plane (e.g., parallel to the floor). Also, the curvatures and sizes of the individual mirrors can be designed to position the beam splitter closer to one of the banks of mirrors to allow the optical pulse stretchers to properly fit in an allocated location in a laser system.

The present invention provides a fiber laser system, comprising: a master laser cavity for generating a master laser beam; a beam splitter for splitting the master laser beam into a first beam for generating a first color pulsed laser beam and a second beam for generating a second color pulsed laser beam; and a synchronization component configured to synchronize the first color pulsed laser beam and a second color pulsed laser beam based on coherent wavelength generation.

A laser apparatus according to an aspect of the present disclosure includes a laser oscillator that outputs pulsed laser light, a deformable mirror including a deformer that deforms a reflective surface, a first processor that drives the deformer during the period for which the reflective surface reflects the pulsed laser light, a homogenizer that homogenizes the pulsed laser light reflected off the deformable mirror, and a spectrum measuring instrument that measures the spectrum of the pulsed laser light homogenized by the homogenizer.

A laser apparatus according to an aspect of the present disclosure includes a master oscillator configured to emit a laser beam, an amplifier including an optical resonator and configured to amplify the laser beam emitted by the master oscillator in the optical resonator, and a phase shift structure disposed on an optical path between the master oscillator and the amplifier at a position closer to the amplifier than a middle point of the optical path. The phase shift structure includes a plurality of cells having different phase shift amounts for the laser beam. The cells have a disposition interval of 80 μm to 275 μm inclusive.

Systems and methods are described that relate to a scanning laser system configured to emit laser light and an interlock circuit communicatively coupled to the scanning laser system. The interlock circuit may carry out certain operations. The operations include, as the scanning laser system emits laser light into one or more regions of an environment around the scanning laser system, determining a respective predicted dosage amount for each region based on the emitted laser light. The operations further include detecting an interlock condition. The interlock condition includes a predicted dosage amount for at least one region being greater than a threshold dose. In response to detecting the interlock condition, the operations include controlling the scanning laser system to reduce a subsequent dosage amount in the at least one region.

Methods and devices are described for performing an all-phase measurement of an ultra-fast laser pulse having a spectral range of greater than one octave. The ultra-fast laser pulse may be split into a first beam comprising a fundamental light with a wavelength λ.sub.0 and a second beam comprising a light with a wavelength 2λ.sub.0. The light with the wavelength 2λ.sub.0 may be frequency doubled to a light with a wavelength λ.sub.0 to generate an interference with the fundamental light. Fourier transform may be performed on an interference spectrum of the interference, and a relative envelope delay (RED) between the fundamental light and the frequency doubled light and a carrier envelope phase (CEP) may be acquired based on a result of the Fourier transform.