LaserStar iWeld 900 Series, Operation & Maintenance Manual

Page: 9 / 172

LaserStar
®
Workstation Operation & Maintenance Manual 900 Series Ver. 991.6 November 2019
9
BACKGROUND
The word “laser” stands for “light amplification by stimulated emission of radiation.”
Lasers are possible because of the way the light interacts with electrons. Electrons
are atomic particles that exist at specific energy levels. These energy levels are
unique and are different for every atom or molecule. The energy levels can be
compared to orbits or rings around the sun or nucleus. Electrons in outer rings are
at higher energy levels than those in the inner rings. A flash of light
Figure 1
can
bump electrons to higher energy levels by the injection of energy. When an
electron drops from an outer ring to an inner ring or level, the excess of energy is
given off as light. The wavelength or the color emitted is related to the amount of
energy released. Depending on the particular lasing medium or material, specific
wavelengths are emitted.
Figure 1
The propagation of light through space can be described in terms of a traveling
wave motion. The wave is composed of a combination of mutually perpendicular
electric and magnetic fields; therefore, the direction of propagation of the wave is
at right angles to both field directions.
Figure 2
shows an
electromagnetic wave.