KaVo KEY Laser III 1243, Technician'S Instructions

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Technician's instructions KEY Laser III 1243
1 Overview of functions
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1.1 Physical basics
Optical pumping
If the laser medium is exposed to high intensity light, higher energy levels can be
populated by means of absorption. This process is referred to as optical pumping.
The light source used for the KEY Laser is a high-intensity xenon flashlamp.
However, since only wavelengths with the exact energy differential between two
levels contribute to pumping the laser medium, it is very important that you choose
the correct flashlamp (a xenon one for the Er:YAG laser) and flashlamp operating
mode.
Under optimal conditions, the flashlamp should only emit light at the frequency best
suited to pumping the laser medium (Er:YAG) up to the higher energy level.
Since the laser transition uses only a part of the excitation energy, the laser wave‐
length generated (Er:YAG: 2.94 µm) is greater than the optimal pumping wavelength
(approx. 780 nm to 840 nm for Er:YAG).
Figure I shows the theoretical curve of the light energy emitted by the flashlamp in
a specific operating mode as a function of wavelength.
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2
Picture 1
① Relative light energy ② Wavelength (nm)
Figure II shows the theoretical curve of the absorption coefficient of the Er:YAG laser
medium as a function of wavelength.
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2
Picture II
② Wavelength (nm) ③ Absorption coefficient
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