This sheath reduces crosstalk between adjacent fibers and loss-increasing microbending that occurs when fibers are pressed against rough surfaces. An optical fiber cable buried in the ground typically contains 100 or more fibers bundled together. The refractive index of the core is higher than that of the cladding. Optical equipment converts voice or data electrons into bits of light called photons. The photons travel across long-distance fiber networks propelled by lasers and amplifiers.
Truncated cable enters a junction box where amplification takes place.
Each individual fiber must be separated. The fibers are then attached to devices that amplify and transmit the signal. An optical signal originates from a modulated light source, such as a laser, that feeds it into a strand of fiber. Launching conditions determine the effectiveness of fiber optic transmissions. Output power depends on the angle over which light is emitted, the size of the light-emitting area, the alignment of the light source and fiber, and the light collection characteristics of the fiber.