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Noun Explanation of Several Common Optical Passive Devices

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Noun Explanation of Several Common Optical Passive Devices

1) What is the PON?

PON is the English abbreviation of Passive Optical Network. Because of its large transmission capacity, low maintenance cost and fiber dosage saving, PON has now become the main optical access technology in the world, and is widely used mainly by the fiber to the home (FTTH) network construction. PON is mainly comprised of OLT, optical splitter and ONU. According to the agreement, PON can be divided into EPON, GPON, WDM-PON and so on.

2) What is the optical passive device?

Optical passive device is a kind of optical components which does not rely on any outside optical or electrical energy, and can do some optical functions by their own, such as coupler, filter and so on. Its working principle complies with the physical and geometrical optics theory, while laser transceiver device based on photoelectric energy conversion is called active devices.

3) How is the optical passive device classified?

Optical passive devices can be classified according to their production process and functions. According to the different production process, optical passive devices can be divided into fiber optical passive devices and integrated optical passive devices. According to the different functions, they can be divided into optical connection devices, optical attenuator, optical splitter, optical wavelength distribution devices, optical isolation devices, optical switch, optical modem devices and so on.

4) What is the main technical indicators to evaluate optical passive devices?

The main technical indicators to evaluate optical passive devices are: insertion loss, return loss, bandwidth, with ups and downs, power allocation error, the wavelength isolation, channel isolation, channel width, extinction ratio, switching speed, speed and so on. Different devices have different requirements of technical indicators, but most of the optical passive devices need the requirements of low insertion loss, high reflection loss, and wide working bandwidth.

5) What is the PLC?

PLC is the English abbreviation of Planar Lightwave Circuit, namely the planar optical waveguide. The optical passive device and traditional vertical difference, PLC devices are used by semiconductor fabrication, which can integrate the optical components with different functions into one chip. PLC is the basic technology of photoelectric device integration, modularization, miniaturization. The devices those are used PLC technology include: optical splitter, arrayed waveguide grating (AWG), variable optical attenuator (VOA), variable optical attenuation combiner (VMUX), reconfigurable optical add-drop multiplexer (ROADM) and so on.

6) What are the advantages of PLC splitter compared to FBT optical splitter?
Compared with the traditional device FBT splitter used of FBT(Fused Biconical Taper) processing, PLC splitter has wide work wavelength channel loss, good uniformity, small volume, wide working temperature range, high reliability, is currently the preferred connection of OLT and ONU and the realization of optical signal power distribution PON the access network.

7) What is the difference between Full-band PLC splitter and three FBT window splitter?

Due to the working principle and the limit of process, traditional FBT splitter can generally meet the transfer at most three different wavelength, which is called the three window splitter. While the loss of PLC splitter is very low in a very wide wavelength range (1260-1650nm), so in addition to meet the three a window outside the commonly used, PLC splitter can also be used for transmission and management more work wavelength. So PLC splitter is called full-band splitter. The wavelength requirements of EPON and GPON standards were 13101490 and 1550nm, the next generation PON standard (such as WDM-PON) will require more work wavelength. The use of PLC optical branch devices can better adapt to the needs of future network upgrade and development.