In contrast to mechanical cutting, which utilizes cutting tools and power-driven equipment, and waterjet cutting, which utilizes pressurized water and abrasive material, laser cutting employs a laser cutting machine to produce cuts, engravings, and markings. While laser cutting machines vary from model to model and application to application, the typical setup includes a laser resonator assembly, mirrors. And a laser cutting head which contains a laser focusing lens, a pressurized gas assembly, and a nozzle. The basic laser cutting process includes the following stages:

• beam generation
• beam focusing
• localized heating and melting
• material ejection
• beam movement

Each stage is integral to the laser cutting process and, when properly executed, producing a precise cut.

Beam Generation

The term “laser” comes from the acronym LASER or Light Amplification by Stimulated Emission of Radiation. Essentially, this acronym summarizes the basic principles of laser generation—stimulation and amplification. Along with these principles, the laser resonator employs the processes of spontaneous emission and stimulated emission to produce a high-intensity beam of light that is both spatially and spectrally coherent (i.e., a laser beam).

• Spontaneous emission:

  The laser resonator contains an active laser medium (e.g., CO₂, Nd:YAG, etc.). An external energy source can stimulat the electrons, for example, a flash lamp or electrical arc. As the medium receives and absorbs energy, its atoms experience a process known as spontaneous emission. During this process, energy absorbed by an atom causes the atom’s electrons to briefly jump to a higher energy level and then return to their ground state. Upon the electrons’ return to their ground state, the atom emits a photon of light.

• Stimulated Emission:

  The photons that are produced by spontaneous emission travel within the medium, which is contained in a cavity of the laser resonator between two mirrors. One mirror is reflective to keep photons traveling within the medium. So they continue to propagate stimulated emissions, and the other mirror is partially transmissive to allow some photons to escape. Stimulated emission is the process in which a photon stimulates an atom that is already at a higher energy level. This interaction forces the stimulated atom to drop to its ground state by emitting a second photon of the same fixed wavelength or coherent with the incident photon.

The process of one photon propagating the emission of another photon amplifies the strength and intensity of the light beam. Thus the stimulated emission of light photons (i.e., a type of electromagnetic radiation) causes the amplification of light; in other words, light amplification by stimulated emission of radiation. Improperly aligned photons within the resonator pass through the partially transmissive mirror without being reflected into the medium, generating the initial laser beam. Once generated, the beam enters the laser cutting head and is directed by mirrors into the focusing lens.

https://www.xtlaser.com/product-item/plate-fiber-laser-cutting-machine-h/

E Series