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Retinal Hazard Region
Selective Absorption
Selective Photothermo- lysis
Specular Reflection
Spot Size
Stimulated Emission
Standard Operating Procedures (SOP)
Thermal Relaxation Time
Transmission Tunable Laser
Ultraviolet Radiation (UV)
Visible Radiation (light)
The wavelength region between 400 and 1400 nm where the tissue damage hazard is greatest on the human retina. Note that most humans can see in the range 380 to around 780 nm, so the wavelengths above 780 nm can damage the retina, even though they are invisible to us.
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. See ‘Diffuse Reflection’ above.
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.
A set of formal, written administrative procedures to be followed when performing specific tasks.
The time to dissipate the heat absorbed by a target chromophore during a laser pulse to 50% (or 1/e) of its peak temperature. The TRT of blood vessels is a cornerstone in the development of the theory of ‘Selective Photothermolysis’. See more here...
Passage of electromagnetic radiation through a medium.
A laser system that can be "tuned" to emit laser light over a continuous range of wavelengths or frequencies.
Electromagnetic radiation with wavelengths between soft X rays and visible violet light, often broken down into UV-A (315-400 nm), UV-B (280-315 nm) and UV-C (100-280 nm).
Electromagnetic radiation which can be detected by the human eye. It is commonly used to describe wavelengths which lie in the range between 380 nm and 780 nm. The peak of the human spectral
Chapter 1 – Fundamentals of Medical/Aesthetic Lasers and IPLs v1.2
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Chapter 1 LEVEL A Fundamentals of Lasers/IPLs
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