How do lasers work on the skin?
Laser light has four properties that distinguishes it from other light sources (like sunlight or the light from an intense pulsed light (IPL) device).
1. Coherence - all the light waves are in step with each other
2. Directionality - all the light waves travel parallel to each other
3. Monochromatic - the light waves in a laser beam are of the same wavelength
4. High intensity - laser light waves can carry a lot of energy
These properties allow the laser to precisely target specific molecules in the skin, delivering higher amounts of energy to that target than other light based treatments. In contrast, IPL devices shine a bright incoherent light consisting of a much broader range of wavelengths. However, IPL still has many useful applications in cosmetic medicine.
Laser light interacts with skin in specific ways.
The diagram below identifies the three major forms of interaction (2, 3 and 4) by which laser can treat various skin conditions in cosmetic medicine.