Page 122 - An Introduction to Laser Tattoo Removal
P. 122

Chapter 2 – Fundamentals of Laser Tattoo Removal v1.0
Depth of Penetration of Light in the Skin
It is useful to know how far light energy penetrates into the skin. This depends on a number of factors including the wavelength and the spot diameter.
Effect of Wavelength
● The penetration depth is the depth within the skin which the light can reach. This is mostly determined by the wavelength of that light and the properties of the tissue.
● In the visible part of the spectrum the penetration depth increases from the blue end to the red end – in other words, blue light is absorbed near the top of the skin while red light can penetrate all the way down to the fatty layer beneath the dermis. Click HERE for a video of this process.
          Epidermis 0.1 mm
Dermis 2 - 3 mm
Subcutis
  Figure 63: Different wavelengths of light penetrate to different depths. Blue light does not go far into the dermis, while red and near infrared penetrates much deeper.
Light from the near IR (infra-red) will also penetrate deeply into the skin. In particular, the light from the Nd:YAG laser (with a wavelength of 1064 nm) can also reach the fatty tissue layer.
________________________________________________________________________ 122
Chapter 2 LEVEL A Laser Tattoo Removal
© The Laser-IPL Guys, 2021





















































































   120   121   122   123   124