Abstract: Methods and apparatus for treating melasma and/or related hyperpigmentation disorders of a patient are disclosed. The treatment includes delivering laser pulses onto a body of the patient, wherein the delivering laser pulses includes two or more of the following steps: i) delivering laser pulses p1 onto the body, wherein each pulse of the laser pulses p1 is configured to have a diameter of at least 100 ?m and a duration of at most 1 ?s; 2) delivering laser pulses p2 onto the body, wherein each pulse of the laser pulses p2 is configured to have a diameter of at least 100 ?m and a duration of more than 1 ?s; 3) delivering laser pulses p3 onto the body, wherein each pulse of the laser pulses p3 is configured to comprise a plurality of microbeams, each microbeam having a diameter below 1 mm.

Abstract: A laser system includes a first laser source with a laser resonator for generating a first pulsed laser beam. The resonator has a back mirror, an outcoupling mirror and an active lasing medium in between. The system includes a second laser source for generating a second pulsed laser beam and an optical block. The optical block includes a coupling polarizer and a first polarization rotator. The optical block is movable back and forth between an active position and a passive position. In its active position the optical block is located between the outcoupling mirror and the active lasing medium such that the coupling polarizer couples the second beam into the laser resonator of the first laser source while the first rotator is positioned between the outcoupling mirror and the coupling polarizer. In the active position of the optical block a second polarization rotator is between it and the back mirror.

Abstract: A laser system includes a first laser source with a laser resonator for generating a first pulsed laser beam. The resonator has a back mirror, an outcoupling mirror and an active lasing medium in between. The system includes a second laser source for generating a second pulsed laser beam and an optical block. The optical block includes a coupling polarizer and a first polarization rotator. The optical block is movable back and forth between an active position and a passive position. In its active position the optical block is located between the outcoupling mirror and the active lasing medium such that the coupling polarizer couples the second beam into the laser resonator of the first laser source while the first rotator is positioned between the outcoupling mirror and the coupling polarizer. In the active position of the optical block a second polarization rotator is between it and the back mirror.

Abstract: In a method for operating a laser system in a Q-switched mode, the laser system provided with a laser resonator with a laser medium and an electro-optical modulator, wherein the electro-optical modulator has an EOM crystal, wherein the EOM crystal has a characteristic ringing time (t0) when subjected to acoustic ringing, the EOM crystal is driven by modulator voltage pulses (pm) having a modulator voltage pulse duration (tml). A train of at least two subsequent laser pulses (pl) is generated. The modulator voltage pulse duration (tml) is selected to be at least approximately equal to the characteristic ringing time (t0) of the EOM crystal multiplied by an integer factor.

Abstract: In a method for operating a laser system in a Q-switched mode, the laser system provided with a laser resonator with a laser medium and an electro-optical modulator, wherein the electro-optical modulator has an EOM crystal, wherein the EOM crystal has a characteristic ringing time (t0) when subjected to acoustic ringing, the EOM crystal is driven by modulator voltage pulses (pm) having a modulator voltage pulse duration (tml). A train of at least two subsequent laser pulses (pl) is generated. The modulator voltage pulse duration (tml)is selected to be at least approximately equal to the characteristic ringing time (t0) of the EOM crystal multiplied by an integer factor.