An optical oscillator according to an embodiment includes a first reflecting portion that transmits light having a first wavelength and reflects light having a second wavelength different from the first wavelength, a second reflecting portion that forms an unstable resonator together with the first reflecting portion and reflect light having the second wavelength, a laser medium that is disposed between the first reflecting portion and the second reflecting portion and emits light having the second wavelength due to incidence of light having the first wavelength, and a saturable absorption portion disposed on a side opposite to the first reflecting portion when viewed from the laser medium in the one direction, the first reflecting portion includes an incidence surface on which light having the first wavelength is incident, on a side opposite to the laser medium, a size of the second reflecting portion is smaller than a size of the first reflecting portion when viewed in the one direction, at least a part of a surface of the saturable absorption body on the side opposite to the laser medium includes a curved region curved toward the laser medium side, and the second reflecting portion is a dielectric multilayer film provided in the curved region.

A fiber coupled modular laser system comprises a laser oscillator, at least one fiber pre-amplifier, and at least one free space solid state power amplifier. The output of the laser oscillator is fiber coupled with the input of the at least one fiber pre-amplifier or the at least one free space solid state power amplifier. The output or the input of the at least one fiber pre-amplifier is fiber coupled with the input or the output of the at least one free space solid state power amplifier.

A MOPA laser system that includes a seed laser configured to output pulsed laser light, an amplifier configured to receive and amplify the pulsed laser light emitted by the seed laser; and a pump laser configured to deliver a pump laser beam to both the seed laser and the amplifier.

The laser cavity is of the unstable type and is provided with a passive Q-switch, the passive Q-switch comprising a saturable absorber that has an absorption gradient, so that the absorption profile of the saturable absorber is inhomogeneous over the cross section of the beam travelling in the laser cavity.

The laser cavity is of the unstable type and is provided with a passive Q-switch, the passive Q-switch comprising a saturable absorber that has an absorption gradient, so that the absorption profile of the saturable absorber is inhomogeneous over the cross section of the beam travelling in the laser cavity.

In a Q-switched solid-state laser having a resonator (3, 30) in the form of a linear resonator or a ring resonator having an active laser material (1) and at least one first and one second mirror (4, 5) and a resonator length (a) of less than 50 mm, preferably less than 25 mm, in the case of the configuration as a linear resonator and of less than 100 mm, preferably less than 50 mm, in the case of the configuration as a ring resonator, at least substantially only one longitudinal mode oscillates in the resonator (3). The resonator (3, 30) is in the form of an unstable resonator, with one of the mirrors (4, 5) being a gradient mirror.

In a Q-switched solid-state laser having a resonator (3, 30) in the form of a linear resonator or a ring resonator having an active laser material (1) and at least one first and one second mirror (4, 5) and a resonator length (a) of less than 50 mm, preferably less than 25 mm, in the case of the configuration as a linear resonator and of less than 100 mm, preferably less than 50 mm, in the case of the configuration as a ring resonator, at least substantially only one longitudinal mode oscillates in the resonator (3). The resonator (3, 30) is in the form of an unstable resonator, with one of the mirrors (4, 5) being a gradient mirror.

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.

A passive Q switching laser device according to an embodiment of the present technology includes: a passive Q switching laser; a signal source; a modulation unit; and a power source unit. The passive Q switching laser includes an excitation light source that emits excitation light, and a resonator that is excited by the excitation light to emit oscillation light. The signal source outputs a drive signal for driving the excitation light source. The modulation unit modulates, on the basis of emission timing at which the oscillation light is emitted from the passive Q switching laser, the drive signal output from the signal source. The power source unit drives, on the basis of the drive signal modulated by the modulation unit, the excitation light source to emit the excitation light.

A passive Q switching laser device according to an embodiment of the present technology includes: a passive Q switching laser; a signal source; a modulation unit; and a power source unit. The passive Q switching laser includes an excitation light source that emits excitation light, and a resonator that is excited by the excitation light to emit oscillation light. The signal source outputs a drive signal for driving the excitation light source. The modulation unit modulates, on the basis of emission timing at which the oscillation light is emitted from the passive Q switching laser, the drive signal output from the signal source. The power source unit drives, on the basis of the drive signal modulated by the modulation unit, the excitation light source to emit the excitation light.