Optical fiber
An optical fiber, or optical fibre, is a flexible
Glass optical fibers are typically made by
Being able to join optical fibers with low loss is important in fiber optic communication.[11] This is more complex than joining electrical wire or cable and involves careful cleaving of the fibers, precise alignment of the fiber cores, and the coupling of these aligned cores. For applications that demand a permanent connection a fusion splice is common. In this technique, an electric arc is used to melt the ends of the fibers together. Another common technique is a mechanical splice, where the ends of the fibers are held in contact by mechanical force. Temporary or semi-permanent connections are made by means of specialized optical fiber connectors.[12]
The field of applied science and engineering concerned with the design and application of optical fibers is known as fiber optics. The term was coined by Indian-American physicist Narinder Singh Kapany.[13]
History
Daniel Colladon and Jacques Babinet first demonstrated the guiding of light by refraction, the principle that makes fiber optics possible, in Paris in the early 1840s.[14] John Tyndall included a demonstration of it in his public lectures in London, 12 years later.[15] Tyndall also wrote about the property of total internal reflection in an introductory book about the nature of light in 1870:[16][17]
When the light passes from air into water, the refracted ray is bent towards the perpendicular... When the ray passes from water to air it is bent from the perpendicular... If the angle which the ray in water encloses with the perpendicular to the surface be greater than 48 degrees, the ray will not quit the water at all: it will be totally reflected at the surface... The angle which marks the limit where total reflection begins is called the limiting angle of the medium. For water this angle is 48°27′, for flint glass it is 38°41′, while for a diamond it is 23°42′.
In the late 19th century, a team of Viennese doctors guided light through bent glass rods to illuminate body cavities.[18] Practical applications such as close internal illumination during dentistry followed, early in the twentieth century. Image transmission through tubes was demonstrated independently by the radio experimenter Clarence Hansell and the television pioneer John Logie Baird in the 1920s. In the 1930s, Heinrich Lamm showed that one could transmit images through a bundle of unclad optical fibers and used it for internal medical examinations, but his work was largely forgotten.[15][19]
In 1953, Dutch scientist
Kapany coined the term fiber optics after writing a 1960 article in Scientific American that introduced the topic to a wide audience. He subsequently wrote the first book about the new field.[19][22]
The first working fiber-optic data transmission system was demonstrated by German physicist Manfred Börner at Telefunken Research Labs in Ulm in 1965, followed by the first patent application for this technology in 1966.[23][24] In 1968, NASA used fiber optics in the television cameras that were sent to the moon. At the time, the use in the cameras was classified confidential, and employees handling the cameras had to be supervised by someone with an appropriate security clearance.[25]
Initially, high-quality optical fibers could only be manufactured at 2 meters per second. Chemical engineer Thomas Mensah joined Corning in 1983 and increased the speed of manufacture to over 50 meters per second, making optical fiber cables cheaper than traditional copper ones.[30][self-published source] These innovations ushered in the era of optical fiber telecommunication.
The Italian research center CSELT worked with Corning to develop practical optical fiber cables, resulting in the first metropolitan fiber optic cable being deployed in Turin in 1977.[31][32] CSELT also developed an early technique for splicing optical fibers, called Springroove.[33]
Attenuation in modern optical cables is far less than in electrical copper cables, leading to long-haul fiber connections with repeater distances of 70–150 kilometers (43–93 mi). Two teams, led by
The emerging field of photonic crystals led to the development in 1991 of photonic-crystal fiber,[37] which guides light by diffraction from a periodic structure, rather than by total internal reflection. The first photonic crystal fibers became commercially available in 2000.[38] Photonic crystal fibers can carry higher power than conventional fibers and their wavelength-dependent properties can be manipulated to improve performance. These fibers can have hollow cores.[39]
Uses
Communication
Optical fiber is used as a medium for
10 or 40 Gbit/s is typical in deployed systems.[40][41]
Through the use of
Date | Milestone |
---|---|
2006 | 111 |
2009 | 100 Pbit/s·km (15.5 Tbit/s over a single 7000 km fiber) by Bell Labs.[44] |
2011 | 101 Tbit/s (370 channels at 273 Gbit/s each) on a single core.[45] |
January 2013 | 1.05 Pbit/s transmission through a multi-core (lightpath) fiber cable.[46] |
June 2013 | 400 Gbit/s over a single channel using 4-mode orbital angular momentum multiplexing.[47] |
October 2022 | 1.84 Pbit/s using a photonic chip[48] |
October 2023 | 22.9 Pbit/s by NICT[49] |
For short-distance applications, such as a network in an office building (see
Fibers are often also used for short-distance connections between devices. For example, most high-definition televisions offer a digital audio optical connection. This allows the streaming of audio over light, using the S/PDIF protocol over an optical TOSLINK connection.
Sensors
Fibers have many uses in remote sensing. In some applications, the fiber itself is the sensor (the fibers channel optical light to a processing device that analyzes changes in the light's characteristics). In other cases, fiber is used to connect a sensor to a measurement system.
Optical fibers can be used as sensors to measure
In contrast, highly localized measurements can be provided by integrating miniaturized sensing elements with the tip of the fiber.
Extrinsic fiber optic sensors use an
Common uses for fiber optic sensors include advanced
Optical fibers are widely used as components of optical chemical sensors and optical
Power transmission
Optical fiber can be used to transmit power using a
Other uses
Optical fibers are used as
Optical fiber is also used in imaging optics. A coherent bundle of fibers is used, sometimes along with lenses, for a long, thin imaging device called an endoscope, which is used to view objects through a small hole. Medical endoscopes are used for minimally invasive exploratory or surgical procedures. Industrial endoscopes (see fiberscope or borescope) are used for inspecting anything hard to reach, such as jet engine interiors.
In some buildings, optical fibers route sunlight from the roof to other parts of the building (see
Optical fiber can also be used in
In spectroscopy, optical fiber bundles transmit light from a spectrometer to a substance that cannot be placed inside the spectrometer itself, in order to analyze its composition. A spectrometer analyzes substances by bouncing light off and through them. By using fibers, a spectrometer can be used to study objects remotely.[54][55][56]
An optical fiber
Optical fiber is also widely exploited as a nonlinear medium. The glass medium supports a host of nonlinear optical interactions, and the long interaction lengths possible in fiber facilitate a variety of phenomena, which are harnessed for applications and fundamental investigation.[57] Conversely, fiber nonlinearity can have deleterious effects on optical signals, and measures are often required to minimize such unwanted effects.
Optical fibers doped with a
Fiber-optic sights for handguns, rifles, and shotguns use pieces of optical fiber to improve the visibility of markings on the sight.
Principle of operation
An optical fiber is a cylindrical
Fiber is immune to electrical interference; there is no cross-talk between signals in different cables and no pickup of environmental noise. Information traveling inside the optical fiber is even immune to electromagnetic pulses generated by nuclear devices.[b][citation needed]
Fiber cables do not conduct electricity, which makes fiber useful for protecting communications equipment in
Fiber cables are not targeted for metal theft. In contrast, copper cable systems use large amounts of copper and have been targeted since the 2000s commodities boom.
Refractive index
The
Total internal reflection
When light traveling in an optically dense medium hits a boundary at a steep angle (larger than the
Because the light must strike the boundary with an angle greater than the critical angle, only light that enters the fiber within a certain range of angles can travel down the fiber without leaking out. This range of angles is called the
Multi-mode fiber
Fiber with large core diameter (greater than 10 micrometers) may be analyzed by
In graded-index fiber, the index of refraction in the core decreases continuously between the axis and the cladding. This causes light rays to bend smoothly as they approach the cladding, rather than reflecting abruptly from the core-cladding boundary. The resulting curved paths reduce multi-path dispersion because high-angle rays pass more through the lower-index periphery of the core, rather than the high-index center. The index profile is chosen to minimize the difference in axial propagation speeds of the various rays in the fiber. This ideal index profile is very close to a parabolic relationship between the index and the distance from the axis.[citation needed]
Single-mode fiber
Fiber with a core diameter less than about ten times the
Special-purpose fiber
Some special-purpose optical fiber is constructed with a non-cylindrical core or cladding layer, usually with an elliptical or rectangular cross-section. These include
Photonic-crystal fiber is made with a regular pattern of index variation (often in the form of cylindrical holes that run along the length of the fiber). Such fiber uses diffraction effects instead of or in addition to total internal reflection, to confine light to the fiber's core. The properties of the fiber can be tailored to a wide variety of applications.
Mechanisms of attenuation
Attenuation in fiber optics, also known as transmission loss, is the reduction in the intensity of the light signal as it travels through the transmission medium. Attenuation coefficients in fiber optics are usually expressed in units of dB/km. The medium is usually a fiber of silica glass[f] that confines the incident light beam within. Attenuation is an important factor limiting the transmission of a digital signal across large distances. Thus, much research has gone into both limiting the attenuation and maximizing the amplification of the optical signal. The four orders of magnitude reduction in the attenuation of silica optical fibers over four decades was the result of constant improvement of manufacturing processes, raw material purity, preform, and fiber designs, which allowed for these fibers to approach the theoretical lower limit of attenuation.[60]
Single-mode optical fibers can be made with extremely low loss. Corning's Vascade® EX2500 fiber, a low loss single-mode fiber for telecommunications wavelengths, has a nominal attenuation of 0.148 dB/km at 1550 nm.[61] A 10 km length of such fiber transmits nearly 71% of light at 1,550 nm. It has been noted that if ocean water was as clear as fiber, one could see all the way to the bottom even of the Mariana Trench in the Pacific Ocean, a depth of 11,000 metres (36,000 ft).[62]
Empirical research has shown that attenuation in optical fiber is caused primarily by both scattering and absorption.
Light scattering
The propagation of light through the core of an optical fiber is based on the total internal reflection of the lightwave. Rough and irregular surfaces, even at the molecular level, can cause light rays to be reflected in random directions. This is called
Scattering depends on the
Thus, attenuation results from the
Similarly, the scattering of light in optical quality glass fiber is caused by molecular level irregularities (compositional fluctuations) in the glass structure. Indeed, one emerging school of thought is that glass is simply the limiting case of a polycrystalline solid. Within this framework, domains exhibiting various degrees of short-range order become the building blocks of metals as well as glasses and ceramics. Distributed both between and within these domains are micro-structural defects that provide the most ideal locations for light scattering. This same phenomenon is seen as one of the limiting factors in the transparency of IR missile domes.[63]
At high optical powers, scattering can also be caused by nonlinear optical processes in the fiber.[64][65]
UV-Vis-IR absorption
In addition to light scattering, attenuation or signal loss can also occur due to selective absorption of specific wavelengths. Primary material considerations include both electrons and molecules as follows:
- At the electronic level, it depends on whether the electron orbitals are spaced (or "quantized") such that they can absorb a quantum of light (or photon) of a specific wavelength or frequency in the ultraviolet (UV) or visible ranges. This is what gives rise to color.
- At the atomic or molecular level, it depends on the frequencies of atomic or molecular vibrations or chemical bonds, how closely packed its atoms or molecules are, and whether or not the atoms or molecules exhibit long-range order. These factors will determine the capacity of the material to transmit longer wavelengths in the infrared (IR), far IR, radio, and microwave ranges.
The design of any optically transparent device requires the selection of materials based upon knowledge of its properties and limitations. The crystal structure absorption characteristics observed at the lower frequency regions (mid- to far-IR wavelength range) define the long-wavelength transparency limit of the material. They are the result of the interactive coupling between the motions of thermally induced vibrations of the constituent atoms and molecules of the solid lattice and the incident light wave radiation. Hence, all materials are bounded by limiting regions of absorption caused by atomic and molecular vibrations (bond-stretching) in the far-infrared (>10 µm).
In other words, the selective absorption of IR light by a particular material occurs because the selected frequency of the light wave matches the frequency (or an integer multiple of the frequency, i.e. harmonic) at which the particles of that material vibrate. Since different atoms and molecules have different natural frequencies of vibration, they will selectively absorb different frequencies (or portions of the spectrum) of IR light.
Reflection and transmission of light waves occur because the frequencies of the light waves do not match the natural resonant frequencies of vibration of the objects. When IR light of these frequencies strikes an object, the energy is either reflected or transmitted.
Loss budget
Attenuation over a cable run is significantly increased by the inclusion of connectors and splices. When computing the acceptable attenuation (loss budget) between a transmitter and a receiver one includes:
- dB loss due to the type and length of fiber optic cable,
- dB loss introduced by connectors, and
- dB loss introduced by splices.
Connectors typically introduce 0.3 dB per connector on well-polished connectors. Splices typically introduce less than 0.2 dB per splice.[citation needed]
The total loss can be calculated by:
- Loss = dB loss per connector × number of connectors + dB loss per splice × number of splices + dB loss per kilometer × kilometers of fiber,
where the dB loss per kilometer is a function of the type of fiber and can be found in the manufacturer's specifications. For example, a typical 1550 nm single-mode fiber has a loss of 0.3 dB per kilometer.[citation needed]
The calculated loss budget is used when testing to confirm that the measured loss is within the normal operating parameters.
Manufacturing
Materials
Glass optical fibers are almost always made from
Plastic optical fibers (POF) are commonly step-index multi-mode fibers with a core diameter of 0.5 millimeters or larger. POF typically have higher attenuation coefficients than glass fibers, 1 dB/m or higher, and this high attenuation limits the range of POF-based systems.
Silica
Silica exhibits fairly good optical transmission over a wide range of wavelengths. In the
Silica can be drawn into fibers at reasonably high temperatures and has a fairly broad
Silica glass can be doped with various materials. One purpose of doping is to raise the refractive index (e.g. with germanium dioxide (GeO2) or aluminium oxide (Al2O3)) or to lower it (e.g. with fluorine or boron trioxide (B2O3)). Doping is also possible with laser-active ions (for example, rare-earth-doped fibers) in order to obtain active fibers to be used, for example, in fiber amplifiers or laser applications. Both the fiber core and cladding are typically doped, so that the entire assembly (core and cladding) is effectively the same compound (e.g. an aluminosilicate, germanosilicate, phosphosilicate or borosilicate glass).
Particularly for active fibers, pure silica is usually not a very suitable host glass, because it exhibits a low solubility for rare-earth ions. This can lead to quenching effects due to the clustering of dopant ions. Aluminosilicates are much more effective in this respect.
Silica fiber also exhibits a high threshold for optical damage. This property ensures a low tendency for laser-induced breakdown. This is important for fiber amplifiers when utilized for the amplification of short pulses.
Because of these properties, silica fibers are the material of choice in many optical applications, such as communications (except for very short distances with plastic optical fiber), fiber lasers, fiber amplifiers, and fiber-optic sensors. Large efforts put forth in the development of various types of silica fibers have further increased the performance of such fibers over other materials.[67][68][69][70][71][72][73][74]
Fluoride glass
Fluoride fibers are used in mid-
An example of a heavy metal fluoride glass is the
Phosphate glass
Phosphate glasses can be advantageous over silica glasses for optical fibers with a high concentration of doping rare-earth ions. A mix of fluoride glass and phosphate glass is fluorophosphate glass.[77][78]
Chalcogenide glass
The
Process
This section needs additional citations for verification. (April 2016) |
Preform
Standard optical fibers are made by first constructing a large-diameter preform with a carefully controlled refractive index profile, and then pulling the preform to form the long, thin optical fiber. The preform is commonly made by three chemical vapor deposition methods: inside vapor deposition, outside vapor deposition, and vapor axial deposition.[80]
With inside vapor deposition, the preform starts as a hollow glass tube approximately 40 centimeters (16 in) long, which is placed horizontally and rotated slowly on a
The oxide particles then agglomerate to form large particle chains, which subsequently deposit on the walls of the tube as soot. The deposition is due to the large difference in temperature between the gas core and the wall causing the gas to push the particles outward in a process known as thermophoresis. The torch is then traversed up and down the length of the tube to deposit the material evenly. After the torch has reached the end of the tube, it is then brought back to the beginning of the tube and the deposited particles are then melted to form a solid layer. This process is repeated until a sufficient amount of material has been deposited. For each layer the composition can be modified by varying the gas composition, resulting in precise control of the finished fiber's optical properties.
In outside vapor deposition or vapor axial deposition, the glass is formed by flame hydrolysis, a reaction in which silicon tetrachloride and germanium tetrachloride are oxidized by reaction with water in an oxyhydrogen flame. In outside vapor deposition, the glass is deposited onto a solid rod, which is removed before further processing. In vapor axial deposition, a short seed rod is used, and a porous preform, whose length is not limited by the size of the source rod, is built up on its end. The porous preform is consolidated into a transparent, solid preform by heating to about 1,800 K (1,500 °C, 2,800 °F).
Typical communications fiber uses a circular preform. For some applications such as double-clad fibers another form is preferred.[81] In fiber lasers based on double-clad fiber, an asymmetric shape improves the filling factor for laser pumping.
Because of the surface tension, the shape is smoothed during the drawing process, and the shape of the resulting fiber does not reproduce the sharp edges of the preform. Nevertheless, careful polishing of the preform is important, since any defects of the preform surface affect the optical and mechanical properties of the resulting fiber.
Drawing
The preform, regardless of construction, is placed in a device known as a drawing tower, where the preform tip is heated and the optical fiber is pulled out as a string. The tension on the fiber can be controlled to maintain the desired fiber thickness.
Cladding
The light is guided down the core of the fiber by an optical cladding with a lower refractive index that traps light in the core through total internal reflection. For some types of fiber, the cladding is made of glass and is drawn along with the core from a preform with radially varying index of refraction. For other types of fiber, the cladding made of plastic and is applied like a coating (see below).
Coatings
The cladding is coated by a buffer that protects it from moisture and physical damage.[68] These coatings are UV-cured urethane acrylate composite or polyimide materials applied to the outside of the fiber during the drawing process. The coatings protect the very delicate strands of glass fiber—about the size of a human hair—and allow it to survive the rigors of manufacturing, proof testing, cabling, and installation. The buffer coating must be stripped off the fiber for termination or splicing.
Today’s glass optical fiber draw processes employ a dual-layer coating approach. An inner primary coating is designed to act as a shock absorber to minimize attenuation caused by
The thickness of the coating is taken into account when calculating the stress that the fiber experiences under different bend configurations.[82] When a coated fiber is wrapped around a mandrel, the stress experienced by the fiber is given by[82]: 45
- ,
where E is the fiber’s Young's modulus, dm is the diameter of the mandrel, df is the diameter of the cladding and dc is the diameter of the coating.
In a two-point bend configuration, a coated fiber is bent in a U-shape and placed between the grooves of two faceplates, which are brought together until the fiber breaks. The stress in the fiber in this configuration is given by[82]: 47
- ,
where d is the distance between the faceplates. The coefficient 1.198 is a geometric constant associated with this configuration.
Fiber optic coatings protect the glass fibers from scratches that could lead to strength degradation. The combination of moisture and scratches accelerates the aging and deterioration of fiber strength. When fiber is subjected to low stresses over a long period, fiber fatigue can occur. Over time or in extreme conditions, these factors combine to cause microscopic flaws in the glass fiber to propagate, which can ultimately result in fiber failure.
Three key characteristics of fiber optic waveguides can be affected by environmental conditions: strength, attenuation, and resistance to losses caused by microbending. External
Cable construction
In practical fibers, the cladding is usually coated with a tough resin and features an additional buffer layer, which may be further surrounded by a jacket layer, usually plastic. These layers add strength to the fiber but do not affect its optical properties. Rigid fiber assemblies sometimes put light-absorbing glass between the fibers, to prevent light that leaks out of one fiber from entering another. This reduces crosstalk between the fibers, or reduces flare in fiber bundle imaging applications.[83][84] Multi-fiber cable usually uses colored buffers to identify each strand.
Modern cables come in a wide variety of sheathings and armor, designed for applications such as direct burial in trenches, high voltage isolation, dual use as power lines,[85][failed verification] installation in conduit, lashing to aerial telephone poles, submarine installation, and insertion in paved streets.
Some fiber optic cable versions are reinforced with aramid yarns or glass yarns as an intermediary strength member. In commercial terms, usage of the glass yarns are more cost-effective with no loss of mechanical durability. Glass yarns also protect the cable core against rodents and termites.
Practical issues
This section needs additional citations for verification. (April 2016) |
Installation
Fiber cable can be very flexible, but traditional fiber's loss increases greatly if the fiber is bent with a radius smaller than around 30 mm. This creates a problem when the cable is bent around corners. Bendable fibers, targeted toward easier installation in home environments, have been standardized as ITU-T G.657. This type of fiber can be bent with a radius as low as 7.5 mm without adverse impact. Even more bendable fibers have been developed.[86] Bendable fiber may also be resistant to fiber hacking, in which the signal in a fiber is surreptitiously monitored by bending the fiber and detecting the leakage.[87]
Another important feature of cable is cable's ability to withstand tension which determines how much force can be applied to the cable during installation.
Termination and splicing
Optical fibers are connected to terminal equipment by
Fusion splicing is done with a specialized instrument. The fiber ends are first stripped of their protective polymer coating (as well as the more sturdy outer jacket, if present). The ends are cleaved (cut) with a precision cleaver to make them perpendicular, and are placed into special holders in the fusion splicer. The splice is usually inspected via a magnified viewing screen to check the cleaves before and after the splice. The splicer uses small motors to align the end faces together, and emits a small spark between
Mechanical fiber splices are designed to be quicker and easier to install, but there is still the need for stripping, careful cleaning, and precision cleaving. The fiber ends are aligned and held together by a precision-made sleeve, often using a clear
Fibers are terminated in connectors that hold the fiber end precisely and securely. A fiber-optic connector is a rigid cylindrical barrel surrounded by a sleeve that holds the barrel in its mating socket. The mating mechanism can be push and click, turn and latch (bayonet mount), or screw-in (threaded). The barrel is typically free to move within the sleeve and may have a key that prevents the barrel and fiber from rotating as the connectors are mated.
A typical connector is installed by preparing the fiber end and inserting it into the rear of the connector body. Quick-set adhesive is usually used to hold the fiber securely, and a
In the 1990s, terminating fiber optic cables was labor-intensive. The number of parts per connector, polishing of the fibers, and the need to oven-bake the epoxy in each connector made terminating fiber optic cables difficult. Today, many connector types are on the market that offer easier, less labor-intensive ways of terminating cables. Some of the most popular connectors are pre-polished at the factory and include a gel inside the connector. Those two steps help save money on labor, especially on large projects. A cleave is made at a required length, to get as close to the polished piece already inside the connector. The gel surrounds the point where the two pieces meet inside the connector for very little light loss.[citation needed] Long-term performance of the gel is a design consideration, so for the most demanding installations, factory pre-polished pigtails of sufficient length to reach the first fusion splice enclosure is normally the safest approach that minimizes on-site labor.
Free-space coupling
It is often necessary to align an optical fiber with another optical fiber or with an
In a laboratory environment, a bare fiber end is coupled using a fiber launch system, which uses a
With properly polished single-mode fibers, the emitted beam has an almost perfect Gaussian shape—even in the far field—if a good lens is used. The lens needs to be large enough to support the full numerical aperture of the fiber, and must not introduce aberrations in the beam. Aspheric lenses are typically used.
Fiber fuse
At high optical intensities, above 2
Chromatic dispersion
The refractive index of fibers varies slightly with the frequency of light, and light sources are not perfectly monochromatic. Modulation of the light source to transmit a signal also slightly widens the frequency band of the transmitted light. This has the effect that, over long distances and at high modulation speeds, the different frequencies of light can take different times to arrive at the receiver, ultimately making the signal impossible to discern, and requiring extra repeaters.[92] This problem can be overcome in several ways, including the use of a relatively short length of fiber that has the opposite refractive index gradient.
See also
- Fiber Bragg grating
- Fiber management system
- The Fiber Optic Association
- Gradient-index optics
- Interconnect bottleneck
- Leaky mode
- Li-Fi
- Light tube
- Modal bandwidth
- Optical communication
- Optical mesh network
- Optical power meter
- Radiation effects on optical fibers
- Return loss
- Subwavelength-diameter optical fiber
Notes
- ultraviolet radiation.
- ^ This feature is offset by the fiber's susceptibility to the gamma radiation from the weapon. The gamma radiation causes the optical attenuation to increase considerably during the gamma-ray burst due to the darkening of the material, followed by the fiber itself emitting a bright light flash as it anneals. How long the annealing takes and the level of the residual attenuation depends on the fiber material and its temperature.
- ^ The fiber, in this case, will probably travel a longer route, and there will be additional delays due to communication equipment switching and the process of encoding and decoding the voice onto the fiber.
- ^ The electromagnetic analysis may also be required to understand behaviors such as speckle that occur when coherent light propagates in multi-mode fiber.
- ^ The behavior of larger-core multi-mode fiber can also be modeled using the wave equation, which shows that such fiber supports more than one mode of propagation (hence the name). The results of such modeling of multi-mode fiber approximately agree with the predictions of geometric optics, if the fiber core is large enough to support more than a few modes.
- ^ For applications requiring spectral wavelengths, especially in the mid-infrared wavelengths (~2–7 μm), a better alternative is represented by fluoride glasses such as ZBLAN and InF3.
References
- ISBN 978-0130326812.
- ^ "Birth of Fiberscopes". www.olympus-global.com. Olympus Corporation. Retrieved 17 April 2015.
- .
- ^ "Optical Fiber". www.thefoa.org. The Fiber Optic Association. Retrieved 17 April 2015.
- ^ "Manufacture of Perfluorinated Plastic Optical Fibers" (PDF). chromisfiber.com. 2004. Retrieved 2023-09-11.
- ^ Senior, pp. 12–14
- ISBN 978-0-07-162935-5. Archived from the originalon 2021-08-17. Retrieved 2021-02-24.
- ^ The Optical Industry & Systems Purchasing Directory. Optical Publishing Company. 1984.
- ISBN 9781351424844.
- ISBN 9780124159815.
- ^ Senior, p. 218
- ^ Senior, pp. 234–235
- ^ "Narinder Singh Kapany Chair in Opto-electronics". ucsc.edu. Archived from the original on 2017-05-21. Retrieved 2016-11-01.
- ^ Colladon, Jean-Daniel (1842). "On the reflections of a ray of light inside a parabolic liquid stream". Comptes Rendus.
- ^ ISBN 978-0-07-137356-2.
- ^ Tyndall, John (1870). "Total Reflexion". Notes about Light.
- ^ Tyndall, John (1873). Six Lectures on Light. New York: D. Appleton.
- ^ Mary Bellis. "How Fiber Optics Was Invented". Archived from the original on 2012-07-12. Retrieved 2020-01-20.
- ^ ISBN 9780195162554.
- S2CID 4275331.
- ^ Two Revolutionary Optical Technologies. Scientific Background on the Nobel Prize in Physics 2009. Nobelprize.org. 6 October 2009
- ^ How India missed another Nobel Prize – Rediff.com India News. News.rediff.com (2009-10-12). Retrieved on 2017-02-08.
- ^ DE patent 1254513, Börner, Manfred, "Mehrstufiges Übertragungssystem für Pulscodemodulation dargestellte Nachrichten.", issued 1967-11-16, assigned to Telefunken Patentverwertungsgesellschaft m.b.H.
- ^ US patent 3845293, Börner, Manfred, "Electro-optical transmission system utilizing lasers"
- ^ Lunar Television Camera. Pre-installation Acceptance Test Plan. NASA. 12 March 1968
- ISBN 978-0-19-510818-7.
- ^ "Press Release – Nobel Prize in Physics 2009". The Nobel Foundation. Retrieved 2009-10-07.
- ISBN 978-0-19-510818-7.
- ^ "1971–1985 Continuing the Tradition". GE Innovation Timeline. General Electric Company. Retrieved 2012-09-28.
- ^ "About the Author – Thomas Mensah". The Right Stuff Comes in Black. Archived from the original on 2 January 2015. Retrieved 29 March 2015.
- ^ Catania, B.; Michetti, L.; Tosco, F.; Occhini, E.; Silvestri, L. (September 1976). "First Italian Experiment with a Buried Optical Cable" (PDF). Proceedings of 2nd European Conference on Optical Communication (II ECOC). pp. 315–322. Retrieved 2022-08-18.
- ^ "15 settembre 1977, Torino, prima stesura al mondo di una fibra ottica in esercizio". Archivio storico Telecom Italia. Archived from the original on 2017-09-17. Retrieved 2017-02-15.
- ^ "Springroove, il giunto per fibre ottiche brevettato nel 1977". Archivio storico Telecom Italia. Archived from the original on 2016-08-16. Retrieved 2017-02-08.
- .
- .
- PMID 19741905.
- S2CID 136470113.
- ^ "The History of Crystal fiber A/S". Crystal Fiber A/S. Retrieved 2008-10-22.
- .
- ^ Yao, S. (2003). "Polarization in Fiber Systems: Squeezing Out More Bandwidth" (PDF). The Photonics Handbook. Laurin Publishing. p. 1. Archived from the original (PDF) on July 11, 2011.
- ^ "JANET Delivers Europe's First 40 Gbps Wavelength Service". Ciena (Press release). 2007-07-09. Archived from the original on 2010-01-14. Retrieved 29 October 2009.
- ^ NTT (September 29, 2006). "14 Tbps over a Single Optical Fiber: Successful Demonstration of World's Largest Capacity" (Press release). Nippon Telegraph and Telephone. Archived from the original on 2017-09-21. Retrieved 2017-02-08.
- ^ Alfiad, M. S.; et al. (2008). "111 Gb/s POLMUX-RZ-DQPSK Transmission over 1140 km of SSMF with 10.7 Gb/s NRZ-OOK Neighbours" (PDF). Proceedings ECOC 2008. pp. Mo.4.E.2. Archived from the original (PDF) on 2013-12-04. Retrieved 2013-09-17.
- ^ Alcatel-Lucent (September 29, 2009). "Bell Labs breaks optical transmission record, 100 Petabit per second kilometer barrier". Phys.org (Press release). Archived from the original on October 9, 2009.
- . Retrieved 2012-02-26.
- ^ "NEC and Corning achieve petabit optical transmission". Optics.org. 2013-01-22. Retrieved 2013-01-23.
- S2CID 206548907. Archived from the original(PDF) on 2019-02-20.
- ^ "Petabit per second data transmission speeds from a single chip-scale light source - DTU Electro".
- ^ World Record Optical Fiber Transmission Capacity Doubles to 22.9 Petabits per Second
- S2CID 32093488.
- ISBN 978-0-470-71066-1.
- ^ Anna Basanskaya (1 October 2005). "Electricity Over Glass". IEEE Spectrum.
- ^ "Photovoltaic feat advances power over optical fiber - Electronic Products". ElectronicProducts.com. 2006-06-01. Archived from the original on 2011-07-18. Retrieved 2020-09-26.
- ^ Al Mosheky, Zaid; Melling, Peter J.; Thomson, Mary A. (June 2001). "In situ real-time monitoring of a fermentation reaction using a fiber-optic FT-IR probe" (PDF). Spectroscopy. 16 (6): 15.
- ^ Melling, Peter; Thomson, Mary (October 2002). "Reaction monitoring in small reactors and tight spaces" (PDF). American Laboratory News.
- ^ Melling, Peter J.; Thomson, Mary (2002). "Fiber-optic probes for mid-infrared spectrometry" (PDF). In Chalmers, John M.; Griffiths, Peter R. (eds.). Handbook of Vibrational Spectroscopy. Wiley.
- ISBN 978-0-12-397023-7.
- ^ Encyclopedia of Laser Physics and Technology. RP Photonics. Retrieved Feb 22, 2015.
- PMID 20111311. Retrieved 2023-12-21.
- S2CID 215789966.
- ^ "Corning Submarine Optical Fibers". Corning.com. Corning Incorporated. Retrieved 28 March 2024.
- ISBN 978-0-240-80751-5.
- .
- PMID 20119362.
- ^ Paschotta, Rüdiger. "Brillouin Scattering". Encyclopedia of Laser Physics and Technology. RP Photonics.
- .
- Bibcode:1999SPIE.CR73....3G.
- ^ .
- .
- doi:10.1109/50.50715.
- S2CID 119534094.
- S2CID 135912790.
- S2CID 137896322.
- .
- .
- S2CID 137381989.
- .
- .
- .
- ISBN 978-0-13-638727-5.
- .
- ^ S2CID 136377895. Archived from the original(PDF) on 2019-05-02. Retrieved 2019-05-02.
- ^ "Light collection and propagation". National Instruments' Developer Zone. National Instruments Corporation. Archived from the original on January 25, 2007. Retrieved 2007-03-19.
- ISBN 978-0-13-027828-9.
- ^ "Screening report for Alaska rural energy plan" (PDF). Alaska Division of Community and Regional Affairs. Archived from the original (PDF) on May 8, 2006. Retrieved April 11, 2006.
- Corning Incorporated. 2007-07-23. Archived from the originalon June 13, 2011. Retrieved 2013-09-09.
- ^ Olzak, Tom (2007-05-03). "Protect your network against fiber hacks". Techrepublic. CNET. Archived from the original on 2010-02-17. Retrieved 2007-12-10.
- ^ "Laser Lensing". OpTek Systems Inc. Archived from the original on 2012-01-27. Retrieved 2012-07-17.
- PMID 12836750.
- ^ Hitz, Breck (August 2003). "Origin of 'fiber fuse' is revealed". Photonics Spectra. Archived from the original on 2012-05-10. Retrieved 2011-01-23.
- ISSN 1348-1797. Retrieved 2008-07-05.
- ^ G. P. Agrawal, Fiber Optic Communication Systems, Wiley-Interscience, 1997.
Further reading
- Agrawal, Govind (2010). Fiber-Optic Communication Systems (PDF) (4th ed.). Wiley. ISBN 978-0-470-50511-3.
- Gambling, W. A. (2000). "The Rise and Rise of Optical Fibers". IEEE Journal of Selected Topics in Quantum Electronics. 6 (6): 1084–1093. S2CID 23158230.
- Mirabito, Michael M. A.; and Morgenstern, Barbara L., The New Communications Technologies: Applications, Policy, and Impact, 5th Edition. Focal Press, 2004. (ISBN 0-240-80586-0).
- Mitschke F., Fiber Optics: Physics and Technology, Springer, 2009 (ISBN 978-3-642-03702-3)
- Nagel, S. R.; MacChesney, J. B.; Walker, K. L. (1982). "An Overview of the Modified Chemical Vapor Deposition (MCVD) Process and Performance". IEEE Journal of Quantum Electronics. 30 (4): 305–322. S2CID 33979233.
- Rajiv Ramaswami; Kumar Sivarajan; Galen Sasaki (27 November 2009). Optical Networks: A Practical Perspective. Morgan Kaufmann. ISBN 978-0-08-092072-6.
- Lennie Lightwave's Guide to Fiber Optics, The Fiber Optic Association, 2016.
- Friedman, Thomas L. (2007). The World is Flat. Picador. ISBN 978-0-312-42507-4. The book discusses how fiber optics has contributed to globalization, and has revolutionized communications, business, and even the distribution of capital among countries.
- GR-771, Generic Requirements for Fiber Optic Splice Closures, Telcordia Technologies, Issue 2, July 2008. Discusses fiber optic splice closures and the associated hardware intended to restore the mechanical and environmental integrity of one or more fiber cables entering the enclosure.
- Paschotta, Rüdiger. "Tutorial on Passive Fiber optics". RP Photonics. Retrieved 17 October 2013.
External links
- The Fiber Optic Association
- "Fibers", article in RP Photonics' Encyclopedia of Laser Physics and Technology
- "Fibre optic technologies", Mercury Communications Ltd, August 1992.
- "Photonics & the future of fibre", Mercury Communications Ltd, March 1993.
- "Fiber Optic Tutorial" Educational site from Arc Electronics
- MIT Video Lecture: Understanding Lasers and Fiberoptics
- Fundamentals of Photonics: Module on Optical Waveguides and Fibers
- Webdemo for chromatic dispersion at the Institute of Telecommunicatons, University of Stuttgart