Laser physics deals with the fundamentals of laser science which includes the theory and practice of lasers. This area of study is primarily concerned with quantum electronics, laser construction, and optical cavity design. A significant understanding of lasers and light sources is required for their optimal use. A basic understanding of laser physics is also mandatory to carry out efficient laser treatment.
LIGHT AND WAVELENGTHS
Light – is the electromagnetic radiation of any wavelength. (light is composed of tiny particles (photons) traveling in a wave-like manner.
Electromagnetic Radiation (EMR) – is the form of energy exhibiting wave-like behavior that has both electric and magnetic field components, perpendicular to each other and perpendicular to the direction of energy propagation.
ELECTROMAGNETIC SPECTRUM OF RADIATION
Electromagnetic spectrum can be defined as forms of energy that travel through space in waves consisting of both electric and magnetic properties. It includes the entire range of light that we can see and the radiation that is invisible to our eyes.
LIGHT-BASED TECHNIQUES FOR HAIR REDUCTION
- Laser and light-based techniques rely on the absorption of melanin in the hair shaft using wavelengths ranging from red, visible light, to near-infrared light.
- These wavelengths range from approximately 700nm – 1100nm in the Electromagnetic Spectrum.
- The light is absorbed by the melanin in the hair causing thermal damage to the hair follicles.
ELECTROMAGNETIC RADIATION
All electromagnetic radiation consists of photons which are individual quantum packets of energy. In this course, we will mainly focus on the part of the electromagnetic spectrum specific to the use of laser for hair removal. This includes visible light and part of near-infrared radiation.
TYPE OF RADIATION |
WAVELENGTH |
Ultraviolet |
100 nm – 400 nm |
Visible light |
400 nm – 750 nm |
Near-Infrared |
750 nm – 3000 nm |
Far Infrared | 3000 nm – 1 mm |