Opticalfiber, also known as optical fiber for short, is a light-conducting tool that uses fibers made of glass or plastic in which light is transmitted by the principle of total internal reflection.
Opticalfiber, also known as optical fiber, is a fiber made of glass or plastic, using light in these fibers to transmit the principle of total internal reflection of the light-conducting tool. The microscopic fiber is encapsulated in a plastic sheath that allows it to be bent without breaking. Typically a transmitting device at one end of the fiber uses a light-emitting diode or a beam of laser light to send pulses of light into the fiber, and a receiving device at the other end of the fiber detects the pulses using a photosensitive component.
The cable that contains the optical fiber is called a fiber-optic cable. The use of optical fibers as a medium for transmitting information over long distances was prompted by the fact that the transmission losses of information in optical fibers are much lower than those of electricity conducted through wires, and even more so by the fact that the main raw material for its production is silicon, which is in great abundance and relatively easy to mine, and so is very inexpensive. As the price of fiber optics is further reduced, it is also being used for medical and recreational purposes.
Basic Principles
Fiber optics are cylindrical dielectric waveguides that apply the principle of total internal reflection to conduct light. The structure of an optical fiber is roughly divided into an inner core part and an outer cladding part. In order to confine the light signal to the core, the refractive index of the cladding must be less than that of the core. The refractive index of a gradient fiber changes slowly, gradually decreasing from the core to the cladding, while the refractive index of a mutant fiber changes dramatically at the core-cladding boundary region.
The angle of light entering the fiber must be less than the angle of the light-accepting angle in order to be conducted through the core of the fiber. The sine of the light-receiving angle is the numerical aperture of the fiber. The larger the numerical aperture of the fiber, the less sophisticated fusion splicing and handling techniques are required. Single-mode fibers have a smaller numerical aperture and require more precise splicing and handling techniques.