Correct Answers 2024
LASER
Light amplification by the stimulated emission of radiation
Light consist of many wave lengths
Laser consist of just one
The FDA approved lasers for permanent hair reduction
In. 1997
When was the Ruby crystal laser invented
In 1960
The Ruby crystal uses what wavelength
694 nm
In 1960 the ruby crystal was invented and used for
Dermatology and ophthalmology
ELECTROMAGNETIC SPECTRUM of RADIATION
Visible and invisible light
The light we see belongs to what spectrum
ELECTROMAGNETIC SPECTRUM of RADIATION
The spectrum of light is arranged by its frequency of its waves
Longest, lowest waves to shortest highest waves. Radio waves are longest and
gamma waves are shortest
Wavelength
Is the measurement between the distance of two consecutive peaks in a wave ( peak
or troughs )
Short wave length
High frequency
High intensity
High melanin absorption
Long wave length
Low frequency
Low intensity
Low melanin absorption
Ruby laser
694nm
Alexandrite
755nm
Diode
800nm , 810nm
Nd Yag
1064nm
Ruby and alexandrite
Short wave length
High frequency
High intensity
Nd Yag
, Long wavelength
Low frequency
Low intensity
Nanometers
Nm
How a Wavelength is measured
Infrared
Lasers are in this wavelength
Radio wave have the longest wavelength in the spectrum
Radio waves
Infrared light ( IR )
Is invisible and thermal
Infrared energy
Felt as heat on the skin and can be captured in thermal imaging
Longest wavelength visible light
Red
Shortest wavelength viable light
Violet
Some laser hair removal devices are in the red light and some are in the near
infrared part of the electromagnetic spectrum
Ultraviolet light
Highly energetic with shorter wavelengths than visible light
UVA rays
95% of UV radiation that reaches the earth
UVA rays
Penetrate the skin more deeply and are dominate tanning rays. Cause photo aging
and skin cancer
UVB rays
Cause skin burns and effect the epidermis. Also cause cancer and photo aging
UVC RAYS
Rays are absorbed by the ozone layer and don't reach the earth
Gamma rays
Have the shortest most powerful wavelength and the most energetic form of light
Gamma rays can kill living cells
Used in medicine to kill cancerous cells
Laser light
Is coherent
Monochromatic
Collimated
IPL Light
Is polychromatic
Scattered and
Non collimated
Construction of a laser
1. Flash lamp, pump source
2. Crystal, laser medium
3. Optical resonators , highly reflective mirror and a partially reflective mirror
YAG
Yttrium aluminum garnet
Coherent energy