A fiber-optic splitter, also known as a

beam splitter A beam splitter or ''beamsplitter'' is an optical device that splits a beam of light into a transmitted and a reflected beam. It is a crucial part of many optical experimental and measurement systems, such as interferometers, also finding wid ...

, is based on a

quartz Quartz is a hard, crystalline mineral composed of silica ( silicon dioxide). The atoms are linked in a continuous framework of SiO4 silicon-oxygen tetrahedra, with each oxygen being shared between two tetrahedra, giving an overall chemical ...

substrate Substrate may refer to: Physical layers *Substrate (biology), the natural environment in which an organism lives, or the surface or medium on which an organism grows or is attached ** Substrate (locomotion), the surface over which an organism lo ...

of an integrated waveguide

optical Optics is the branch of physics that studies the behaviour and properties of light, including its interactions with matter and the construction of instruments that use or detect it. Optics usually describes the behaviour of visible, ultrav ...

power distribution device, similar to a coaxial cable transmission system. The optical network system uses an optical signal coupled to the branch distribution. The

fiber optic An optical fiber, or optical fibre in Commonwealth English, is a flexible, transparency and translucency, transparent fiber made by Drawing (manufacturing), drawing glass (silica) or plastic to a diameter slightly thicker than that of a Hair ...

splitter is one of the most important passive devices in the

optical fiber An optical fiber, or optical fibre in Commonwealth English, is a flexible, transparency and translucency, transparent fiber made by Drawing (manufacturing), drawing glass (silica) or plastic to a diameter slightly thicker than that of a Hair ...

link. It is an optical fiber tandem device with many input and output terminals, especially applicable to a passive optical network ( EPON,

GPON G.984, commonly known as GPON (gigabit-capable passive optical network), is a standard for passive optical networks (PON) published by the ITU-T. It is commonly used to implement the outermost link to the customer (last kilometre or last mile) of ...

, BPON,

FTTX Fiber to the ''x'' (FTTX; also spelled "fibre") or fiber in the loop is a generic term for any broadband network architecture using optical fiber to provide all or part of the local loop used for Last mile (telecommunications), last mile tel ...

FTTH Fiber to the ''x'' (FTTX; also spelled "fibre") or fiber in the loop is a generic term for any broadband network architecture using optical fiber to provide all or part of the local loop used for last mile telecommunications. As fiber optic ...

etc.) to connect the main distribution frame and the terminal equipment and to branch the optical signal.

Types

According to the principle, fiber optic splitters can be divided into Fused Biconical Taper (FBT) splitter and Planar Lightwave Circuit (PLC) splitters. The FBT splitter is one of the most common. FBT splitters are widely accepted and used in passive networks, especially for instances where the split configuration is smaller (1×2, 1×4, 2×2, etc.). The PLC is a more recent technology. PLC splitters offer a better solution for larger applications. Waveguides are fabricated using

lithography Lithography () is a planographic method of printing originally based on the immiscibility of oil and water. The printing is from a stone ( lithographic limestone) or a metal plate with a smooth surface. It was invented in 1796 by the German ...

onto a silica glass substrate, which allows for routing specific percentages of light. As a result, PLC splitters offer accurate and even splits with minimal loss in an efficient package.

Balanced splitters

Balanced (2xN) splitters consists of 2 input fibers and N output fibers which divide the power of the optical signal proportionally. They are mainly used for non-simultaneous redundancy. {{cite web, url=http://www.furukawa.com.br/_php/downloadIndireto.php?numeracao=2373&idioma=2 , title=2xN Balanced Optical Splitter , accessdate= 13 April 2017

Splitting ratio principle

Wave splitting involves dividing a light beam into multiple streams. The daughter streams can be equal or in some other ratio. The FBT splitter uses two (or more) fibers. The fibers' coating layer is removed. Both fibers, at the same time, are stretched under a heating zone thus forming a double cone. This special waveguide structure allows control of the splitting ratio via controlling length of the fiber torsion angle and stretch. The PLC splitter is a micro-optical element using

photolithographic In integrated circuit manufacturing, photolithography or optical lithography is a general term used for techniques that use light to produce minutely patterned thin films of suitable materials over a substrate, such as a silicon wafer, to protec ...

techniques to form optical waveguide at medium or

semiconductor A semiconductor is a material which has an electrical conductivity value falling between that of a conductor, such as copper, and an insulator, such as glass. Its resistivity falls as its temperature rises; metals behave in the opposite way. ...

substrate for realizing branch distribution function.

Advantages and disadvantages

* The FBT splitter offers low cost, common materials (quartz substrate, stainless steel, fiber, hot dorm, GEL), and an adjustable splitting ratio. However, its losses are wavelength-dependent, it offers poor spectral uniformity, cannot ensure uniform spectroscopy, and is temperature sensitive. * PLC splitter: Losses are not sensitive to the wavelength, spectral uniformity is higher, it is more compact and is lower cost with greater degrees of splitting. However, device fabrication process is more complex.

References

Fiber-optic communications

Types

Balanced splitters

Splitting ratio principle

Advantages and disadvantages

See also

References