Fiber attenuator as a light passive device for optical communication system which debug optical power performance, debugging fiber optic instrument calibration correction, fiber signal attenuation. The product is made of attenuating optical fibers Fiber Optic Attenuator with metal ions, which adjusts the optical power to the desired level.
Fiber optic attenuator according to the type of port can be divided into the following categories:
Fiber optic attenuator: used in SC fiber interface, it looks very similar to the RJ-45 interface, but the SC interface is more flat, the obvious difference is inside the contact, if it is 8 fine copper contacts, then RJ-45 interface, if it is a copper column is SC fiber interface.
LC fiber attenuator: used in LC fiber interface, connected to the SFP module connector, which uses a convenient modular jack (RJ) latch mechanism made. (Commonly used by routers)
FC fiber attenuator: used in FC fiber interface, external reinforcement is the use of metal sets, fastening for the screw Fiber Optic Attenuator buckle. Generally used in the ODF side (the most used on the patch panel)
ST fiber attenuator: used in ST fiber interface, commonly used in fiber patch panels, shell was round, fastening way for the screw buckle. (For 10Base-F connections, the connector is usually of type ST. Commonly used in fiber patch panels)
Fiber Optic Attenuator Working Principle
1, air isolation technology
Light transmission in the fiber by the total reflection of the law constraints, can not be scattered out to maintain the strength of the relatively stable. And once it is separated from the fiber, in the fiber and fiber to join the air between the interval, the light will be scattered out, causing light attenuation. As the light from the ordinary fiber into the air Fiber Optic Attenuator scattering is very strong, so to control the attenuation of a certain range, we must ensure that the isolation distance and maintain the alignment of the two ends of the fiber. Through this principle can be made flange fixed attenuator and adjustable attenuator. Flange fixed attenuator using isolation attenuator, according to the curve to produce a certain thickness of the attenuation film, the attenuation film implanted in the flange, can play a fixed light attenuation effect. Flange type adjustable optical attenuator using mechanical rotation principle, through the mechanical rotation to adjust the distance between the two ends of the connector can make the light attenuation between 0 ~ 30dB.
2, displacement dislocation technology, this method is the two fiber core of the micro-shift misalignment, so as to achieve the effect of power loss.
Through the use of ordinary pigtail, with the welding machine to the two pigtail core in the case of dislocation welding work, so that the optical transmission in the process of partial core loss, the connector-type fixed attenuator, also known as on-line fixed attenuator The
3, attenuation of fiber technology, according to the metal ions on the absorption of light, developed a mixed metal ion Fiber Optic Attenuator attenuation fiber, and ordinary fiber attenuation coefficient per kilometer, this attenuation fiber also has a fixed attenuation coefficient, but this attenuation The coefficient is not calculated in kilometers, but in millimeters. Will the attenuation of fiber into the ceramic ferrule? After a special process? Can be made of yin-yang fixed attenuator.
4, absorption of glass method
The optically polished neutral absorbing glass sheet can also be applied to the fabrication of optical attenuators. The use of material absorption of light characteristics, made of sheet or strip of neutral dark glass, placed on the optical path, Fiber Optic Attenuator you can light intensity attenuation. The absorptive glass is distinguished by the transmittance T and the decay rate expressed in decibels. Transmittance T = transmitted light intensity / incident light intensity, decay rate η = 1 / T, decay rate in decibels β = 10 x logη = - 10 x logT, attenuation rate in decibels can be easily estimated The decay rate of the decay rate is the decay rate of the combined attenuator group, expressed in decibels. The sheet is made of a fixed attenuation value, and the strip is different depending on the attenuation of the different parts of the dark matter in its continuous increments. A single piece of sheet-like light-absorbing glass can be used to make a fixed attenuator. A plurality of sheet-shaped absorptive glasses can be made by disk-to-disk conversion. The strip-shaped absorptive glass can be made into a continuously adjustable attenuator by continuous displacement.