With the development and progress of laser technology, laser treatment of tattoos is also increasingly mature, the treatment results are also gradually progress. However, there are still some factors that the current existing laser technology is still unable to solve. If the prosperous progress of modern laser technology, is a beautiful dance of artistic sense, then the existence of certain objective factors, such as shackles, shackling the “dancer. This is now introduced for you one by one: 1, the nature of tattooing and time. Professional tattoos are more difficult to completely remove than non-professional tattoos; the longer the tattoo, the easier to go. 2, the color of the tattoo. Compared to blue-black tattoos, red, yellow and green tattoos are more difficult to remove. 3, the composition of the pigment particles. The complex composition of the pigment on the laser response is not the same, it is difficult to choose the type of laser and energy density, often requiring multiple treatments with a variety of lasers. 4, the pigment particles in the dermis, the number and thickness of the accumulation. The greater the density of tattoo pigment particles, the thicker the more difficult to treat. 5, the pigment particles of different sizes. Some pigment particles are larger, the laser is difficult to completely crush, macrophages are difficult to engulf them, in general, because professional tattoo pigment particles are larger and contain organic metal dyes placed in the depths, and amateur tattoos with a carbon matrix of ink particles are smaller, and thus more difficult to remove professional tattoos. 6, the depth of the pigment particles present. Location is deeper, the laser treatment is difficult to reach the appropriate level, most need multiple treatments. 7, the treatment parameters of the laser. As mentioned earlier, which has the greatest impact is the laser wavelength, pulse width, energy density, only choose the appropriate laser to play a good treatment effect.