Page 264 - Chapter 3 - Laser/IPL Hair Removal

Pulse Duration
Pulsed Laser Q-Switch
Radiant Exposure
Radiation
Retinal Hazard Region
Ruby
Selective Absorption
Selective Photothermo- lysis
Specular Reflection
Spot Size
Stimulated Emission
Thermal Relaxation Time
Transmission
The pulse duration is simply the length of the pulse of light (measured in milliseconds or nanoseconds in many aesthetic/medical systems). It is also called the pulsewidth or pulse length. See more here...
Laser which delivers energy in the form of a single or train of pulses.
A Q-switch is an optical device designed to force the laser energy within a pumping chamber to be released in a fraction of the normal emission time, typically nanoseconds.
The total energy per unit area incident upon a given surface. It is used to express exposure to pulsed laser radiation in units of J/cm2. It is commonly referred to as ‘Energy Density’ or ‘Fluence’ in many skin-laser centres.
In the context of optics, electromagnetic energy is released; the process of releasing electromagnetic energy.
Optical radiation with wavelengths between around 400 and 1400 nm, where the principal hazard is usually to the retina.
The first laser type; a crystal of sapphire (aluminium oxide) containing trace amounts of chromium oxide.
Selective absorption is the process by which the melanin in hair absorbs red light preferentially in the skin. Other skin constituents do not absorb this light as much and hence are not affected by the light.
The process by which tissue is heated following selective absorption of incident light energy. This technique allows target tissues to be destroyed without damaging the surrounding tissues.
A mirror-like reflection.
The mathematical measurement of the radius of the laser beam. From this the spot’s area can be calculated and, hence, the energy or power densities. See more here...
When an atom, ion or molecule capable of lasing is excited to a higher energy level by an electric charge or other means, it will spontaneously emit a photon as it decays to the normal ground state. If that photon passes near another atom of the same energy, the second atom will be stimulated to emit a photon.
The time to dissipate the heat absorbed by a target chromophore during a laser pulse to 50% (or 1/e) of its peak temperature. See more here...
Passage of electromagnetic radiation through a medium.
Chapter 3 – Fundamentals of Laser/IPL Hair Removal 2nd Edition
________________________________________________________________________ 264 Chapter 3, Ed. 2.0 Laser/IPL Hair Removal
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