The epidermis is also known as the outer layer of the skin, and is a thin layer found directly above the dermis. Acting as a barrier between the environment and the body’s internal makings, the epidermis is made of flat cells that block the sun or any harmful UV rays. The epidermis also controls the amount of sweat produced to regulate the body’s temperature. This is why the skin will change colors when it’s reacting to the sun, certain chemical compounds, burns, scratches, and other skin damage. The epidermis is proactively working to protect the body by producing melanin, which controls the pigment, or color, of the skin.
Older lasers used for laser tattoo removal would harm the epidermis, as they produced shorter wavelengths that, in addition to targeting the pigment found in tattoo ink, would also target and remove the pigment found in skin. This was especially a problem for those with tanned or darker skin tones, making such individuals less likely candidates for laser tattoo removal treatments. If they chose to move forward with treatment, they would be more likely to experience hypopigmentation, or the discoloration of the skin.
Now, medical lasers used by most licensed laser technicians produce longer wavelengths. This allows lasers to penetrate the epidermis without damaging the skin, as longer wavelengths will only target pigment found in the dermis layers of the skin.