Which factor does NOT affect the depth of penetration in laser treatments?

The depth of penetration in laser treatments is influenced by several factors, including the power of the laser, the wavelength of the light being emitted, and the spot size of the laser beam. However, the color of the skin does not affect the depth of penetration itself but rather the absorption characteristics of the laser light.

The skin color influences how much light is absorbed or reflected by the skin. Darker skin contains more melanin, which can absorb certain wavelengths of light more efficiently, potentially leading to more superficial effects. However, the actual depth the laser light penetrates into the tissue is largely determined by its wavelength characteristics, the energy output (power), and the area that is being treated (spot size). Thus, while skin color can impact treatment outcomes due to absorption rates, it does not directly impact how deeply the laser can penetrate into the tissue.