"Picosecond lasers are q-switched lasers that have a pulse of picoseconds, which is much faster than a nanosecond. That is really the significance. They are more expensive machines (often double the price of a nanosecond q-switch laser) but often only use one wavelength. Only having one wavelength means it is effective for only one tattoo colour and will mean you will again spend more money trying to get a half decent tattoo removal.
Picosecond systems are vastly underpowered compared to nanosecond systems. This forces practitioners to use smaller laser spot sizes when fluence (energy dispersion) levels need to be increased. No picosecond system gives practitioners the flexibility to effectively treat the full spectrum of tattoo colours and patient skin types. A study comparing tattoo fading responses from picosecond and nanosecond lasers found that “the qualitative nature of the ink changes were no different between that of tattoos treated with the two types of lasers.”
Producing picosecond lasers with high pulse energy have proven to be both difficult and prohibitively expensive. Because of these difficulties, the picosecond systems that have made it to market have not delivered on their marketing promises and are plagued with reliability issues." Renude Laser Clinic, Syndey
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