Principles of Laser Processing

What is Laser

Laser is light amplified by absorbing radiant energy. Laser radiation is generated by a laser source, and high-density energy excites crystal rods (solid-state lasers) or special gas mixtures 
(gas lasers) to generate laser radiation. This energy is provided in the form of light (flash lamp or diode laser) or electric discharge (equivalent to fluorescent lamp). A crystal rod or 
laser-activated gas is located between the two mirrors to form a laser resonant cavity to guide the laser to a specific direction and amplify the optical signal in this way. The laser passes 
through the transparent mirror in a certain proportion and is used for material processing.
Solid-State-Laser-Structure

Principles of Laser Processing
All lasers contain the following three components:

Pump source
Stimulated medium
Resonant cavity
The pump source supplies energy from an external source to the laser.

The excited medium is located inside the laser. Depending on the design of the laser structure, the laser medium may be a gas mixture (CO2 laser), crystal rod (YAG solid laser) or glass fiber 
(fiber laser). When the laser medium is supplied with energy from an external pump source, it is excited to generate energy radiation.

The excited medium is located in the middle of the two mirrors at both ends of the resonant cavity. One of the mirrors is a one-way lens (half mirror). The energy radiation generated by the
excited medium is amplified in the resonant cavity. At the same time, there is only one specific The radiation can pass through the one-way lens to form a beam of radiation, which is the 
laser.
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Laser has three main characteristics:
Uniformity: laser radiation contains only one specific wavelength of light
Coherence: the same phase
Parallelism: The light in the laser beam is highly parallel
The laser light is highly parallel before passing through the focusing lens. Within the focal length of the laser beam, extremely high energy intensity is generated, which can be used to melt or evaporate materials. In addition, the use of appropriate optical elements (lenses) can guide and reflect laser light, and there will be no loss even at long distances. The positioning system (laser pointer) or galvanometer scanner is used as a mobile system. Since the laser beam will not be passivated, this is a universal, wear-free tool.

Post time: Jun-15-2021