Lasers remove tattoos by breaking up the pigment colors with a high-intensity light beam. Black tattoo pigment absorbs all laser wavelengths, making it the easiest color to treat. Other colors can only be treated by selected lasers based upon the pigment color.
The number of treatments you will need will depend on the age, size, and color(s) of your tattoo. The color of your skin, as well as how deep the tattoo pigment goes, will also affect the removal technique.