Based on the number of transmission modes in optical fiber, optical fibers can be classified into multimode fiber and single-mode fiber.
2022-01-13
In fiber-optic communication, single-mode optical cable is a type of cable designed to transmit a single light mode. It primarily consists of a core, a cladding, and a coating layer.
Single-mode fiber (SMF), also referred to as “sm,” consists primarily of a core, a cladding, and a coating. The core is made of a highly transparent material, while the cladding has a refractive index slightly lower than that of the core, creating a waveguide effect that confines most of the electromagnetic field within the core for transmission. The coating serves to protect the fiber from moisture ingress and mechanical abrasion, while also enhancing its flexibility. In addition, a plastic jacket is often applied over the coating.
Outdoor single-mode optical cable
Single-mode optical cables and multimode fibers can employ either a step-index refractive index profile or a graded-index profile; single-mode fibers, by contrast, predominantly use the step-index profile. Consequently, quartz optical fibers can broadly be categorized into three types: multimode step-index fibers, multimode graded-index fibers, and single-mode step-index fibers. The propagation of light—as an electromagnetic wave—within an optical fiber constitutes guided wave propagation in a dielectric cylindrical waveguide. When total internal reflection occurs at the interface between media, the electromagnetic wave is confined within the medium, giving rise to a guided wave or guided mode. For a given guided wave and operating wavelength, multiple incident conditions can satisfy the condition for total internal reflection; these correspond to the different modes of the guided wave. Based on the number of propagating modes, optical fibers are classified as multimode fibers and single-mode fibers. Multimode fibers can support the propagation of several modes, whereas a single-mode fiber can support only a single mode at a specified operating wavelength.
The cutoff wavelength λc is defined as the shortest operating optical wavelength that allows single-mode transmission in an optical fiber. In other words, even if all other conditions are met, single-mode transmission cannot be achieved if the optical wavelength is greater than or equal to the cutoff wavelength of the single-mode fiber.
Based on the number of propagation modes supported, optical fibers can be classified into multimode fibers and single-mode fibers. At a given operating wavelength, a multimode fiber is a dielectric waveguide that can support multiple modes, whereas a single-mode fiber supports only the fundamental mode.
Previous:
Kolorapus Special Cable (Shanghai) Co., Ltd
Address: Building 1, No. 351 Chengjian Road, Minhang District, Shanghai
Phone: 021-52961776
Hotline: 400-168-0366 13046617250
Email: joy.liu@sh-apus.com
Friendship Links:
