Tattoo is in order to decorate or beautify the body, in the skin with exogenous insoluble pigment particles and the formation of permanent artificial pigment spots. Tattoo in the face as a tattoo eyebrows, eyeliner and lip tattoo, in the trunk and extremities is called tattoo, they are cosmetic tattoo. In addition to color changes in the skin, can be completely normal, no conscious symptoms, but also can leave varying degrees of scar tissue. Tattooing can cause various types of complications: induce scarring, keloid, foreign body reaction to the tattoo pigment, photosensitivity, allergic reactions, etc.. If sterilization is not strict, it can also cause the transmission of certain diseases (such as tuberculosis, syphilis, leprosy, etc.). Q-switched Nd:YAG, ruby and emerald lasers are currently available for the treatment of tattoos. Q-switched technology can generate 1X109W (gigawatt) of energy in a very short period of time (1-50ns), which can produce instantaneous (ns-level) tissue heat of up to 300 degrees, resulting in rapid thermal expansion of the tissue, thus causing the target tissue to be crushed into very small particles, and this rapid thermal expansion This rapid thermal expansion results in a shock wave process on the tissue called the photoacoustic effect. These small particles are then removed by the body’s phagocytes. The effect of laser tattoo removal with a variety of factors, such as occupational tattoos are generally deep levels, pigment content, deep color, containing a variety of colors, complex composition, treatment requires 8-12 times, colored tattoos are not easy to completely remove. Amateur tattoo level more superficial and most of the carbon pigments, light color, easy to cure, generally 4-6 times. Generally speaking, shallow tattoos, a treatment that can receive significant results, and even completely fade, but for the color and site are deeper tattoos, a treatment is difficult to completely eliminate, usually requires multiple treatments. The treatment effect of tattoo has a great relationship with the nature of the pigment, in general, the pigment used in tattoo is finer, the composition is purer, the treatment effect is more significant, most of them can be significantly faded or completely faded after one treatment, and the more complex tattoo can also be faded after several treatments. Tattoo treatment results vary according to its color, the same color tattoo may contain completely different pigments, with different laser absorption characteristics. In addition some cosmetic tattoos, such as white, light pink, brown or brown, some are mixed colors, containing iron and titanium ions of the dye, the laser action, will change to blue-black, the mechanism may be Fe2O3 changed to feO, then the tattoo color may be deepened, and is permanent. If you want to treat, you must do a trial treatment in the local, such as black, and then further to see if it can become light again, sure to do the full area of treatment again. Q-switched Nd:YAG laser machine can be issued 1064nm and 532nm two wavelengths of laser, the former for the treatment of black tattoos, the latter is used for red tattoos, this long-wave laser for dark-skinned patients is safer and more effective treatment, generally does not leave a scar. However, many complex and professional tattoos themselves that have damage to the skin, tattoo removal in the skin will be left with traces, such as skin texture or color changes, or even the formation of superficial scarring. Traumatic tattoo foreign particles are not only coarse, complex composition, and deposited in all layers of the skin, treatment is much more difficult than tattooing, usually difficult to completely remove, more need for multiple treatments, the treatment is difficult to grasp the depth, easily lead to scar formation. Avoid sun exposure and apply sunscreen after tattoo treatment.