With the popularity of laser cutting machine, it is no longer a special technology for today's society. However, the rapid development of laser cutting technology in recent years, especially the continuous improvement of power, has promoted the upgrading of laser cutting machines. Whether it is cutting technology, pipe nesting technology, or pipe cutting technology, there have been changes to varying degrees. Fiber laser cutting machine is a very popular equipment with high processing efficiency. Compared with traditional processing equipment, it can produce and cut materials in large quantities. Today, with the rapid development of the industry, it is very reused by the company.

A conventional laser of fiber laser cutting machine includes three parts: working material, pump source and optical resonator.

Working material is the material basis of laser, the core part of laser, and the material system used to realize particle number inversion and generate stimulated radiation. There are usually two ways to classify working substances: one is to classify working substances according to their existing forms, which can be divided into gas, solid, liquid and semiconductor; The other is to analyze the energy level structure applicable to the process of generating laser according to the rate equation theory, which can be divided into three-level system and four level system.

In the gas laser, the particles that generate the laser of the fiber laser cutter are gas molecules or atoms. In the solid laser, the crystal or glass doped with a small amount of transition metal ions or rare earth ions is the working material, and the doped ions are the working particles. After the number of particles is inverted by external energy pumping, stimulated radiation can be generated. The crystal and glass are the matrix materials.

The working substance of liquid laser is liquid, and the common one is dye laser. Its working substance is a solution composed of dye dissolved in solvent, dye molecules are working particles, and solvent is equivalent to matrix. The working material of semiconductor lasers is semiconductors. Although semiconductors are solids, the formation mechanism of particle number inversion of semiconductor lasers is fundamentally different from that of ordinary solid-state lasers, so they are generally not classified into one category.

The pump source is a device that provides energy for particle number inversion. According to the energy forms used during excitation, the pumping modes include discharge excitation, optical excitation, thermal energy excitation, chemical energy excitation, etc.

Gas discharge excitation is a commonly used excitation method for gas lasers. Its excitation mechanism is that under high voltage, gas molecules ionize and conduct electricity. At the same time, gas molecules (or atoms and ions) collide with electrons accelerated by the electric field, absorb the energy of electrons, and then jump to the high energy level, forming a particle number inversion; In addition, the high-speed electrons generated by the electron gun can also be used to pump the working material and make it transition to the high-energy level, which is called electron beam excitation; Semiconductor lasers are pumped by injection current, which is called injection pumping.

Optical excitation is to use light to irradiate the working material, and the working material of the fiber laser cutting machine will generate particle number inversion after absorbing light energy. The light source for light excitation can be a high-efficiency and high-intensity light-emitting lamp, solar energy or laser. Solid and liquid lasers are commonly excited by light.

Thermal energy excitation is to increase the number of gas particles on the high-energy level by high-temperature heating, and then suddenly reduce the gas temperature. Because the thermal relaxation time of high and low energy levels is different, the relaxation time of low-energy level is short, and the relaxation time of high-energy level is long, so as to realize the inversion of the number of particles between high and low energy levels.

Chemical energy excitation uses the chemical energy released in the chemical reaction process to pump particles to the upper energy level and establish particle number inversion. Unlike the aforementioned discharge excitation, optical excitation and thermal excitation, chemical excitation requires external energy when working. Therefore, in some special places lacking power supply, chemical lasers can give play to their advantages of fiber laser cutter.

Optical resonator optical resonator (optical resonator for short) is the external condition for generating laser, and is an important part of laser. The simplest optical resonator is composed of two mirrors coated with high reflectivity materials placed properly on both ends of the activation medium. With the characteristics of high directivity, high monochromaticity, high coherence and high brightness, the fiber laser cutting machine is inseparable from the optical resonator.

The optical resonator has dual functions of positive feedback and mode selection. The so-called positive feedback, that is, the initial light intensity travels back and forth between the mirrors, is equivalent to increasing the length of the active medium, and finally a certain size of light intensity can be guaranteed. The so-called mode selection is to control the characteristics of the oscillating beam in the cavity, so that the oscillation of the fiber laser cutter established in the cavity is limited to a few intrinsic modes determined by the cavity, so as to increase the number of photons in a single mode and obtain strong coherent light with good monochromaticity and directivity.

Laser is an electromagnetic wave. The optical resonator of the laser constrains the electromagnetic wave in a limited range of space. According to Maxwell's electromagnetic field theory, there can only be a series of split eigenstates of the electric progressive wave in a certain range of space. These eigenstates are the modes of the optical resonator. The laser mode is also the distinguishable eigenstates of the electric burst in the optical cavity, which is determined by the structure of the cavity.

To sum up, the laser of the fiber laser cutting machine is basically composed of three parts: the working material, the pump source and the optical resonator. These three parts have their own roles and cooperate with each other to promote the work of the laser cutting machine.

About HGTECH: HGTECH is the pioneer and leader of laser industrial application in China, and the authoritative provider of global laser processing solutions. We have comprehensively arranged laser intelligent equipment, measurement and automation production lines, and smart factory construction to provide overall solutions for intelligent manufacturing.