How Many Types of Fiber Laser Generators?

 

fiber laser generator refers to lasers that use rare-earth element-doped glass fibers as gain media. The fiber laser generator generally uses fiber gratings as resonators and semiconductor lasers as pump sources. And the pump light is coupled to the gain fiber from the beam combiner. Then it is reflected multiple times through the doped core in the cladding to form population inversion and output lasers.

I.TYPES OF OUTPUT LASER

A pulsed laser refers to a single laser with a pulse width of less than 0.25S. And it only works once at a certain interval. The main feature of pulsed fiber lasers is that the peak power is high, but the average power is generally low. It is mainly used in laser marking, engraving, and other fields. A continuous wave (CW) fiber laser generator can emit light continuously. And it has the characteristics of stable power output, good photoelectric conversion rate, high cost performance, and long life service.

II.GAIN MEDIUM

1.CRYSTAL FIBER LASER GENERATOR

The working material is laser crystal fiber, mainly including ruby single crystal fiber laser generator and YAG single crystal fiber laser (Nd3+ ) generator.

2. NONLINEAR FIBER LASER GENERATOR

It is mainly divided into the stimulated Raman scattering fiber laser generators and stimulated Brillouin scattering fiber laser generators.

3. RARE EARTH DOPED FIBER LASER GENERATOR

Doping rare earth element ions into the fiber to activate it, (Nd3+, Er3+, Yb3+, Tm3+, etc., the matrix can be quartz glass, zirconium fluoride glass, or single crystal) to make a fiber laser generator.

4. PLASTIC FIBER LASER GENERATOR

Fiber laser generators are made by doping laser dyes into the core or cladding of the plastic fiber.

III.STRUCTURE OF THE RESONANT CAVITY

According to the resonant cavity structure, it is divided into the fiber laser generators with F-P cavity, ring cavity, loop reflector fiber resonator, “8” shape cavity, DBR fiber laser, DFB fiber laser, etc.

IV.FIBER STRUCTURE

Based on the fiber structure, it can be classified as the single-clad fiber laser generator, double-clad fiber laser generator, photonic crystal (PCF) fiber laser generator, and special fiber laser generator.

Photonic crystal fiber lasers have many advantages such as high integration, tunability, and good thermal management performance, and are widely used in scientific fields such as fiber laser communications, industrial manufacturing, medical equipment, and military defense.

Double-clad fiber laser generator represents the development of new fiber laser generators. And it is composed of concentric cores, inner cladding, outer cladding, and protective layers. It does not need to couple the pump energy directly into the fiber with a relatively small mode field diameter. On the contrary, it can use a multi-mode high-power semiconductor laser as the pump source.

V.TRANSMISSION SIGNAL

Fiber lasers can be divided into single-mode and multi-mode. Single-mode fiber lasers use single-mode fiber as the gain medium, and only operate the fundamental mode laser stably. The single-mode laser has concentrated energy and a small divergence angle, which is very advantageous in laser processing that requires high energy density, but the power is generally below 2kw. There are both fundamental modes and other high-order modes in the multimode fiber laser, so the beam is divergent, the spot is larger, and the power is higher, which is more suitable for processing that requires a larger heating area.

VI.NUMBER OF LASER OUTPUT WAVELENGTHS

In terms of the wavelength, the fiber laser generators can be divided into multi-wavelength fiber laser generators and single-wavelength fiber laser generators. The multi-wavelength laser generator can provide the required light source for multiple channels at the same time. And it makes the design of the optical transmitter more compact and economical.