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Fiber optic splitter, also known as a beam splitter, is based on a quartz substrate of an integrated waveguide optical power distribution device, similar to a coaxial cable transmission system. The optical network system also needs to be an optical signal coupled to the branch distribution. In which requires the fiber optic splitter is one of the most important passive devices in the optical fiber link, is optical fiber tandem device with many input terminals and many output terminals, especially applicable to a passive optical network (EPON, GPON, BPON, FTTX, FTTH etc.) to connect the MDF and the terminal equipment and to achieve the branching of the optical signal. Fused Biconical Taper splitter is one of the most common splitters. As this technology has been developed over time, the quality of FBT splitters is very good and they can be deployed in a cost-effective manner. FBT splitters are widely accepted and used in passive networks, especially for instances where the split configuration is smaller (1x2, 1X4, 2x2, etc.).〔(【引用サイトリンク】title=FBT Splitter )〕 Planar Lightwave Circuit is a more recent technology. PLC splitters offer a better solution for applications where larger split configurations are required. To achieve this, waveguides are fabricated using lithography onto a silica glass substrate, which allows for routing specific percentages of light. As a result, PLC splitters offer very accurate and even splits with minimal loss in an efficient package.〔(【引用サイトリンク】title=PLC Splitter )〕 Fiber optic splitter is a key optical device in passive optical network (PON) systems, also known as a passive optical splitter, which splits the optical signal power evenly into all the output ports. In the PON field plant, a 1 × 8 to 1 × 32 splitter is placed on an electric pole, connecting the distribution optical cable in the air and the drop wire to the customer premises. A 1 × ''N'' splitter can be part of an ''N'' × ''N'' star coupler. For example, a 16 × 16 star coupler with four-stage topology is shown in the figure beside, and the dotted line denotes a 1 × 16 splitter. The star coupler can be constructed by cascading 3-dB couplers in the perfect shuffe topology. The 3-dB coupler has two input and two output ports, and it splits the input power 50:50 to the output ports. The number of 3-dB couplers required for the case with ''k''-stage 1 × dBcoupler is given by: ''N''3 dB coupler = 2k - 1, ''k'' = log2''N'' and the splitting loss per output port is given by: Splitting loss = 3 ''k'' () For a 1 × 16 splitter, k = 4, the number of 3-dB couplers required is 31, and the splitting loss per output port is 12 dB + splice Loss appr 0.3 dB per stage. 1 x 16 splitter is 12 dB + 4 x 0.4 = 12+1.6 = 13.6 dB Higher order splitters can be constructed as ''k''-stage arrays of such couplers. They have one or two input ports and ''N''3 dB coupler = 2k output ports, as shown in the figure below. The number of output ports is called the split ratio, which corresponds to the maximum number of ONUs that can be connected.〔(Fiber Optic Couplers and Splitters Tutorial )〕 ==Types== According to the principle, fiber optic splitters can be divided into FBT (Fused Biconical Taper) splitter and PLC (Planar Lightwave Circuit) splitter. FBT splitter is made out of materials that are easily available, for example steel, fiber, hot dorm and others. All of these materials are low-price, which determines the low cost of the device itself. The technology of the device manufacturing is relatively simple, which has the impact on its price as well. In scenario where multiple splits are needed, the size of the device may become an issue. It is important to keep in mind that splitters are being deployed in the fields either in cabinets or in strand mountings, so the size of device plays a critical role. FBT splitters only support three wavelengths (850/1310/1550 nm) which makes these devices unable to operate on other wavelengths. Inability of adjusting wavelengths makes FBT splitters less customizable for different purposes. Moreover, the devices are to a high extent temperature sensitive, providing a stable working range of -5 to 75 °C. In certain areas, such as Scandinavian countries this temperature restrictions may be crucial. The signal processed by FBT splitters cannot be split evenly due to lack of management of the signals. PLC splitter manufacturing technology is more complex. It uses semiconductor technology (lithography, etching, developer technology) production, hence it is more difficult to manufacture. Therefore, the price of the device is higher. However, there is a number of advantages the device possesses. The size of the device is compact, compared to FBT splitters, making it suitable for density applications. PLC splitter operates at wider temperature range (-40 to 85 °C), allowing its deploying in the areas of extreme climate. The split ratio goes up to 64, providing a high reliability. Furthermore, the signal can be split equally due to technology implemented. A range of wavelengths (1260 – 1650 nm) is provided, so the wavelengths are adjustable. Critical points of the device that might fail are input and output, so the general risk of failure is low. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Fiber optic splitter」の詳細全文を読む スポンサード リンク
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