Page 29 - Lasers and IPLs in Medical/Aesthetic Applications v1.2
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Chapter 1 – Fundamentals of Medical/Aesthetic Lasers and IPLs v1.2
Lasers are used in many applications today. There are literally thousands of different types of lasers in existence. It’s now virtually impossible to keep up with the advances in the technology and the creation of new lasers (unless you are ‘special’!!).
 When we both started working in this field in the 1980’s it was relatively easy to learn about the medical lasers used around the world. There weren’t that many, to be honest! However, due to the explosion of devices and applications, there are now so many that we have never heard of. That makes it much more difficult to figure out which laser is best for which application. Hopefully, this book will assist you in understanding a little bit more about them.
What makes a laser, a ‘laser’?
● Lasers are a purely man-made construct. There are no known sources of laser light in the universe other than here on Earth. The light from a laser is unique in that it simultaneously possesses three particular properties that are not found in ‘ordinary’ light:
Monochromaticity Divergence Coherence
● All lasers emit a beam of light with only one colour. This is known as monochromaticity – single colour. In other words, the beam has a single wavelength (with a small ‘spread’).
● This colour/wavelength is determined by the laser medium. You may remember from above (‘Spontaneous Emission’) that the light emitted from a laser is entirely due to the electron orbital energies in the laser medium’s atoms.
● This explains why lasers can only emit a single wavelength – unless you change the medium inside it!
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Chapter 1 LEVEL A Fundamentals of Lasers/IPLs
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