Fiber lasers have a wide range of applications, including laser fiber communication, laser space remote communication, industrial shipbuilding, automobile manufacturing, laser engraving, laser marking, laser cutting, printing rollers, metal and non-metal drilling / cutting / welding (brazing, quenching, cladding and deep welding), military defense security, medical instruments and equipment, large-scale infrastructure, as the pump source of other lasers, and so on.
Because the working medium of fiber laser is in the form of fiber, its characteristics are affected by the transconductance of fiber. The pump light entering the fiber generally has multiple modes, while the signal photoelectric may have multiple modes. Different pump modes have different effects on different signal modes, which makes the analysis of fiber lasers and amplifiers more complex. In many cases, it is difficult to obtain analytical solutions, and numerical calculations have to be used. The doping distribution in the fiber also has a great impact on the fiber laser. In order to make the medium have gain characteristics, the working ions (i.e. impurities) are doped into the fiber. Generally, the working ions are evenly distributed in the core, but the distribution of different modes of pump light in the fiber is uneven. Therefore, in order to improve the pump efficiency, we should try to make the ion distribution coincide with the pump energy distribution. When analyzing the fiber laser, in addition to the general principle of the laser discussed above, we should also consider its own characteristics, introduce different models and adopt special analysis methods to achieve the best analysis results. Fiber laser cutting machine
Like traditional solid-state and gas lasers, fiber lasers are also composed of three basic elements: pump source, gain medium and resonator. The pump source generally adopts high-power semiconductor laser, and the gain medium is rare earth doped fiber or ordinary nonlinear fiber. The resonator can be composed of various linear resonators by optical feedback elements such as fiber grating, or various ring resonators by couplers. The pump light is coupled into the gain fiber through an appropriate optical system. After absorbing the pump light, the gain fiber forms particle number inversion or nonlinear gain and generates spontaneous emission. After the spontaneous emission light is subjected to the mode selection of excitation amplification and resonator, a stable laser output is finally formed.