Fiber structure and type:

Update:21 Jun 2017

1. Fiber structure:Fiber optic bare fiber is generally […]

1. Fiber structure:Fiber optic bare fiber is generally divided into three layers: the center of the high refractive index glass core (core diameter is generally 50 or 62.5μm), the middle of the low refractive index silicon glass cladding (diameter is generally 125μm), the most is reinforced resin coating Floor.
2. Numerical aperture:Light incident on the end of the fiber can not be all transmitted by the fiber, but in a certain range of the incident light can be. This angle is called the numerical aperture of the fiber. The numerical aperture of the fiber is somewhat advantageous for docking of the fiber. Different manufacturers of optical fiber numerical aperture of different (AT & T CORNING).
3. Type of fiber:
⑴. According to the light in the fiber transmission mode can be divided into: single-mode fiber and multi-mode fiber.
Multi-mode fiber: the center of the glass core thick (50 or 62.5μm), can pass a variety of modes of light. But its mode dispersion is large, which limits the frequency of transmission of digital signals, and with the increase in the distance will be more serious. For example: 600MB / KM fiber at 2KM when only 300MB of bandwidth. Therefore, the distance from the multi-mode fiber transmission is relatively close, generally only a few kilometers. Single-mode fiber: the center of the glass core is thin (core diameter is generally 9 or 10μm), can only pass a model of light. Therefore, the dispersion between the mold is very small, suitable for remote communication, but its chromatic dispersion plays a major role, so that single-mode fiber on the spectral width and stability of the light source has a higher demand, that spectrum width is narrow, The
⑵. According to the best transmission frequency window points: conventional single-mode fiber and dispersion-shift single-mode fiber.
Conventional: fiber manufacturers to optimize the optical fiber transmission frequency in a single wavelength of light, such as 1300nm.
Dispersion displacement type: fiber production long home optical fiber transmission frequency optimization in the two wavelengths of light, such as: 1300nm and 1550nm.
⑶. According to the distribution of refractive index points: mutant and gradient type fiber.
Mutation: The refractive index of the fiber core core to the glass cladding is abrupt. Its low cost, high dispersion between models. Applicable to short-distance low-speed communications, such as: industrial control. However, single-mode fiber due to inter-mode dispersion is very small, so single-mode fiber using mutant.
Gradient fiber: fiber core core to the glass cladding refractive index is gradually smaller, high-mode light can be transmitted in sinusoidal form, which can reduce the mold dispersion, improve fiber bandwidth, increase transmission distance, but the higher cost, and now more Modular fiber is mostly progressive fiber.
4. Commonly used fiber specifications:
Single mode: 8/125 μm, 9/125 μm, 10/125 μm
Multimode: 50 / 125μm, European standard
62.5 / 125μm, American Standard
Industrial, medical and low speed networks: 100 / 140μm, 200 / 230μm
Plastic: 98 / 1000μm for automotive control log on to our official website for more details :