Connection and application of energy transmission optical fiber

  For the application of energy-transmitting optical fiber in lasers, the main index to measure its performance is the coupling efficiency of laser and optical fiber, or the laser transmission efficiency of optical fiber (it can also be expressed by insertion loss/connection loss). This includes the connection between the laser and the energy-transmitting optical fiber, as well as the connection between the energy-transmitting optical fiber and the energy-transmitting optical fiber, or the connection between the energy-transmitting optical fiber and the ordinary single-mode optical fiber.

  After decades of commercial development, the coupling connection between energy-transmitting optical fibers and optical fibers, the connection of conventional large-core-diameter optical fibers, can be easily realized by commercial large-core-diameter fusion splicers just like ordinary single-mode optical fibers. As for the special geometric fiber with a large core diameter, since its core diameter and core structure are different from ordinary single-mode fiber, and different application scenarios may have different requirements, its connection method is often more complicated.

Directly couple the laser light source with the energy transmission fiber 

(1)   Direct coupling, that is, the fiber end is installed close to the laser light source so that the generated laser light is directly coupled into the fiber. In order to improve the coupling efficiency, the fiber end is usually processed into a spherical, conical, or parabolic microscopic surface Structural shape; at this time, the size and divergence angle of the light emitting surface of the laser light source, the end face size, numerical aperture, shape of the optical fiber, and the distance between the two will all affect the coupling efficiency.

(2)   Indirect coupling, that is, through the lens to achieve the coupling of the laser with the optical fiber; the lens can be a single lens or a combined lens system composed of multiple lenses; there are also various types of lenses, such as cylindrical lenses, ball lenses, hemispherical lenses There are different combinations and usage forms. The output laser is calibrated by the fast axis and slow axis beams and then focused into the fiber core through a collimating lens.

The development direction of energy transmission optical fiber

  In the future, the main development direction of energy transmission optical fiber will still focus on higher transmission efficiency and greater transmission power. Higher transmission efficiency is mainly to make a breakthrough in the connection coupling technology of energy-transfer optical fibers; on the one hand, greater transmission power can be optimized for existing energy-transmission optical fibers, or a new optical fiber structure can be designed, on the other hand, it can also We can start from the material aspect. In particular, although the current quartz glass material has good transmission performance in the visible and near-infrared wavelength ranges, it is powerless to transmit laser energy at infrared wavelengths. It is urgent to study new materials available.