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Classification and Types of Sensors
FIGURE 2.109 Solid laser with optical pumping source. 117
the atoms, ions, or molecules of the active medium, their energy is
transferred and excitation occurs. The atoms, ions, and electrons
within the active medium are called plasma.
Figure 2.110 is a schematic drawing of a gas laser system with
electrical excitation. The gas mixture is held in a gas plasma tube and
the power supply is connected to the ends of the plasma tube. When
the power supply is turned on, electron movement within the tube is
from the negative to the positive terminal.
2.12.2.2.3 Chemical Excitation Chemical excitation is used in a num-
ber of lasers. When certain chemicals are mixed, energy is released as
chemical bonds are made or broken. This energy can be used as a
pumping source. It is most commonly used in hydrogen-fluoride
lasers, which are extremely high-powered devices used primarily in
FIGURE 2.110 Gas laser with electrical excitation.
