Picosecond laser apparatus and methods for its operation and use

摘要

Apparatuses and methods are disclosed for applying laser energy having desired pulse characteristics, including a sufficiently short duration and/or a sufficiently high energy for the photomechanical treatment of skin pigmentations and pigmented lesions, both naturally-occurring (e.g., birthmarks), as well as artificial (e.g., tattoos). The laser energy may be generated with an apparatus having a resonator with the capability of switching between a modelocked pulse operating mode and an amplification operating mode. The operating modes are carried out through the application of a time-dependent bias voltage, having waveforms as described herein, to an electro-optical device (e.g., a Pockels cell) positioned along the optical axis of the resonator.

主权项

1. A method for treating a skin pigmentation, the method comprising generating pulsed laser energy by
a) reflecting laser energy generated by a lasing medium between a first mirror at one end of a resonator and a second mirror at the opposite end of said resonator and through a polarizer and one or additional electro-optical devices within said resonator and generating a modelocked pulse within the resonator by applying a periodic voltage waveform to the one or additional electro-optical devices; and (b) then amplifying the modelocked pulse by applying to said one or additional electro-optical devices a first constant voltage and maintaining an effective reflectivity of the second mirror at substantially 100%; and (c) then extracting the amplified modelocked pulse from the resonator, and exposing pigmented skin of a patient to the pulsed laser energy.