Abstract: Lasers capable of lasing at at least two wavelengths are provided having a lasing medium which is capable of lasing at a first wavelength and at a second wavelength. An output coupler is positioned along a longitudinal axis at a first end of the lasing medium and a first mirror, movable beam block shutter and second mirror are positioned sequentially along the longitudinal axis of the lasing medium at a second end of the lasing medium. The first mirror is highly reflective at a first wavelength, and the second mirror is highly reflective at a second wavelength while being transparent at the first wavelength. The beam block shutter is movable between a first position along the longitudinal axis of the lasing medium and between the first and second mirrors and a second position away from the longitudinal axis of the lasing medium.

Abstract: A long pulse alexandrite laser hair removal system is disclosed using light pulses of greater than 1 msec and fluences between 10 and 50 J/cm2. The use of an alexandrite laser allows good penetration while still achieving an acceptable combination of hemoglobin and melanin absorption. The use an index-matching application on the skin sections to be treated is also described. This substance will be absorbed into the epidermal layer to provide better coupling of the laser light into the skin. Also, and most advantageously, it will reduce reflections at the epidermal-dermal junction, which can lead to the damage of the skin. Also a topical thermal or photochromic indicator is suggested since skin irradiation in the near-infrared generally does not produce any characteristic skin color change as is found when using pulsed dye lasers, for example.

Abstract: A long pulse alexandrite laser hair removal system is disclosed using light pulses of greater than 1 msec and fluences between 10 and 50 J/cm.sup.2. The use of an alexandrite laser allows good penetration while still achieving an acceptable combination of hemoglobin and melanin absorption. The use an index-matching application on the skin sections to be treated is also described. This substance will be absorbed into the epidermal layer to provide better coupling of the laser light into the skin. Also, and most advantageously, it will reduce reflections at the epidermal-dermal junction, which can lead to the damage of the skin. Also a topical thermal or photochromic indicator is suggested since skin irradiation in the near-infrared generally does not produce any characteristic skin color change as is found when using pulsed dye lasers, for example.

Abstract: A long pulse alexandrite laser hair removal system is disclosed using light pulses of greater than 1 msec and fluences between 10 and 50 J/cm.sup.2. The use of an alexandrite laser allows good penetration while still achieving an acceptable combination of hemoglobin and melanin absorption. The use an index-matching application on the skin sections to be treated is also described. This substance will be absorbed into the epidermal layer to provide better coupling of the laser light into the skin. Also, and most advantageously, it will reduce reflections at the epidermal-dermal junction, which can lead to the damage of the skin. Also a topical thermal or photochromic indicator is suggested since skin irradiation in the near-infrared generally does not produce any characteristic skin color change as is found when using pulsed dye lasers, for example.

Abstract: A method or apparatus for controlling the output pulse of a Q-switched laser. The intensity of laser light within the resonator of a Q-switch laser is sensed. A reference pulse related to a desired laser output pulse shape is compared with the sensed intensity. A variation signal corresponding to differences between the sensed light intensity and the reference pulse is fed to a Pockels cell or Q-switch within the resonator. The Q-switch responds to the variation signal by altering the resonator laser light polarization to maintain the Q-switch laser's output pulse in the desired shape. The reference pulse may be dynamically altered to change the shape of the output pulse.