How does a laser work?

How does a laser work - Basics

In the following video, we will roughly show you the operating principle and the structure of a laser.

The term "Laser"

LASER is an acronym and stands for "Light Amplification by Stimulated Emission of Radiation". In simple terms: Light particles (photons) excited with current emit energy in the form of light. This light is bundled into a beam. Thus, the laser beam is formed.

Technical structure of a laser

Laser technology basics

All lasers consist of three components:

An external pump source
The active laser medium
The resonator

The pump source guides external energy to the laser.

The active laser medium is located on the inside of the laser. Depending on the design, the laser medium can consist of a gas mixture (CO₂ laser), of a crystal body (YAG laser) or glass fibers (fiber laser). When energy is fed to the laser medium through the pump, it emits energy in the form of radiation.

The active laser medium is located between two mirrors, the "resonator". One of these mirrors is a one-way mirror. The radiation of the active laser medium is amplified in the resonator. At the same time, only a certain radiation can leave the resonator through the one-way mirror. This bundled radiation is the laser radiation.

Properties of a laser beam: monochromatic and high coherence

Laser radiation has three fundamental properties:

Monochromatic. This means that the radiation consists of only one wavelength.
High coherence and thereby phase coincidence.
The waves of the laser are approximately parallel due to the coherence.

Due to these properties, the laser light is used in many areas of modern material processing. The intensity is preserved for a long time due to the coherence and can be bundled even further through lenses. The laser beam impinges on the material surface, is absorbed and thus heats the material. Due to this generation of heat, the material can be removed or completely evaporated. It is thus possible to engrave, to mark or to cut a plurality of materials.

You want to learn more about how Trotec laser machines work?

Our laser experts are happy to answer your questions about our products and laser processing. They will help you discover all the possibilities of laser engraving, cutting and marking. Additionally we invite you to see our lasers and applications at one of our demonstration facilities.

Further information regarding laser engraving, cutting and marking

Because individual requirements require individual advice.
We’ll advise you free of charge.