Successful laser tattoo removal depends on four important factors:  1.Penetration: The laser light must go deep into the skin to reach the tattoo pigment.  2.Absorption: The color of the laser light must be more highly absorbed by the tattoo pigment than the surrounding skin. Different tattoo pigments therefore require different laser colors.  3.Duration: The laser pulse must be very quick (nanoseconds to picoseconds) so that the tattoo pigment is heated to fragmentation temperature before its heat can dissipate to the surrounding skin and cause burns or scarring. 4.Intensity: Each laser pulse must deliver enough energy to fragment the pigment. If not, no removal will take place.