79-595: Singtel Optus Pty Limited is an Australian telecommunications company headquartered in Macquarie Park , a suburb in the Northern Sydney region of Sydney , New South Wales , Australia. It is a wholly owned subsidiary of Singaporean telecommunications company Singtel . Optus is the second-largest telecommunications company in Australia, with over 11 million customers as of 2023. Its mobile network covers 98.5% of
158-414: A core surrounded by a cladding layer, both of which are made of dielectric materials. To confine the optical signal in the core, the refractive index of the core must be greater than that of the cladding. The boundary between the core and cladding may either be abrupt, in step-index fiber , or gradual, in graded-index fiber . Light can be fed into optical fibers using lasers or LEDs . Fiber
237-411: A wavelength shifter collect scintillation light in physics experiments . Fiber-optic sights for handguns, rifles, and shotguns use pieces of optical fiber to improve the visibility of markings on the sight. An optical fiber is a cylindrical dielectric waveguide ( nonconducting waveguide) that transmits light along its axis through the process of total internal reflection. The fiber consists of
316-661: A 10-year partnership agreement with the Australian Olympic Committee to be the official partner of the Australian Olympic Team and the Australian Paralympic Team until 2026. In 2017, Optus won naming rights to Perth Stadium where it would be known as Optus Stadium. Optus and the Government of Western Australia agreed to a 10-year naming right worth approximately A$ 50 million. Optus also has
395-426: A 16,000-kilometer distance, means that there is a minimum delay of 80 milliseconds (about 1 12 {\displaystyle {\tfrac {1}{12}}} of a second) between when one caller speaks and the other hears. When light traveling in an optically dense medium hits a boundary at a steep angle of incidence (larger than the critical angle for the boundary), the light is completely reflected. This
474-452: A 50% stake in the now defunct OPEL Networks . Other wholly owned subsidiaries of note no longer have a significant active role as individual entities. These are as follows: Reef Networks was formed in 1999 to provide an optical fibre link between Brisbane and Cairns in Queensland . Optus gained exclusive access to this link in 2001, ahead of acquiring the organisation in 2005. XYZed
553-423: A cladding made of pure silica, with an index of 1.444 at 1500 nm, and a core of doped silica with an index around 1.4475. The larger the index of refraction, the slower light travels in that medium. From this information, a simple rule of thumb is that a signal using optical fiber for communication will travel at around 200,000 kilometers per second. Thus a phone call carried by fiber between Sydney and New York,
632-404: A combined cost estimated of over A$ 6bn. Whilst Telstra focused on creating a broadband network specifically for broadcast, Optus designed their cable network to provide telephony services in addition to broadcast television. Optus is no longer a customer of Telstra's after deciding to move the funding used to lease Telstra 's copper network into constructing their hybrid fibre-coaxial network,
711-447: A digital audio optical connection. This allows the streaming of audio over light, using the S/PDIF protocol over an optical TOSLINK connection. 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
790-522: A lasting impact on structures . It is based on the principle of measuring analog attenuation. 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. An optical fiber doped with certain rare-earth elements such as erbium can be used as
869-752: A long-term partnership with the Adelaide Crows in the AFL . Optus has been a partner of the Collingwood Magpies in the AFL Women's since 2018. Optus is the current major sponsor for the No. 25 Walkinshaw Andretti United Holden ZB Commodore driven by Chaz Mostert Global Telcom Awards : AI Initiative of the year Telecommunications in Australia Too Many Requests If you report this error to
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#1732858405170948-408: A loss and with moves to deregulate telecommunications in Australia , the government decided to sell Aussat, coupled with a telecommunications licence. The licence was sold to Optus Communications – a consortium including: The new telecommunications company was designed to provide competition to then government owned telecommunications company Telecom Australia , now known as Telstra . Optus gained
1027-423: A network in an office building (see fiber to the office ), fiber-optic cabling can save space in cable ducts. This is because a single fiber can carry much more data than electrical cables such as standard category 5 cable , which typically runs at 100 Mbit/s or 1 Gbit/s speeds. Fibers are often also used for short-distance connections between devices. For example, most high-definition televisions offer
1106-474: A sensor to a measurement system. Optical fibers can be used as sensors to measure strain , temperature , pressure , and other quantities by modifying a fiber so that the property being measured modulates the intensity , phase , polarization , wavelength , or transit time of light in the fiber. Sensors that vary the intensity of light are the simplest since only a simple source and detector are required. A particularly useful feature of such fiber optic sensors
1185-649: A target without a clear line-of-sight path. Many microscopes use fiber-optic light sources to provide intense illumination of samples being studied. 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
1264-574: A telephone number. The group began by building an interstate fibre optic cable and a series of exchanges between Optus' interstate network and Telstra's local network. It also laid fibre optics into major office buildings and industrial areas, and focused on high bandwidth local, (interstate) long distance, and interstate calls for business. In its early years, Optus was only able to offer local and long-distance calls to residential customers through Telstra's local phone network. Telstra would carry residential to residential calls to Optus' exchanges, and then
1343-520: A transparent cladding. Later that same year, Harold Hopkins and Narinder Singh Kapany at Imperial College in London succeeded in making image-transmitting bundles with over 10,000 fibers, and subsequently achieved image transmission through a 75 cm long bundle which combined several thousand fibers. The first practical fiber optic semi-flexible gastroscope was patented by Basil Hirschowitz , C. Wilbur Peters, and Lawrence E. Curtiss, researchers at
1422-468: 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 . 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 . Daniel Colladon and Jacques Babinet first demonstrated
1501-453: Is a way of measuring the speed of light in a material. Light travels fastest in a vacuum , such as in outer space. The speed of light in vacuum is about 300,000 kilometers (186,000 miles) per second. The refractive index of a medium is calculated by dividing the speed of light in vacuum by the speed of light in that medium. The refractive index of vacuum is therefore 1, by definition. A typical single-mode fiber used for telecommunications has
1580-411: 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
1659-412: Is called multi-mode fiber , from the electromagnetic analysis (see below). In a step-index multi-mode fiber, rays of light are guided along the fiber core by total internal reflection. Rays that meet the core-cladding boundary at an angle (measured relative to a line normal to the boundary) greater than the critical angle for this boundary, are completely reflected. The critical angle is determined by
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#17328584051701738-418: Is called total internal reflection . This effect is used in optical fibers to confine light in the core. Most modern optical fiber is weakly guiding , meaning that the difference in refractive index between the core and the cladding is very small (typically less than 1%). Light travels through the fiber core, bouncing back and forth off the boundary between the core and cladding. Because the light must strike
1817-537: Is capable of running 3G at 900 MHz is now required after 2G was completely disconnected across Australia. On October 28 2024, the 3G UMTS service provided by Optus was shut down. This affects other providers reliant on their network, including Amaysim and Virgin Mobile Australia . To remain connected, customers are required to have a phone capable of connecting to their 4G LTE or 5G NR services. All phones incapable of using VoLTE will be prevented from accessing
1896-507: Is designed for use in the near infrared . Multi-mode fiber, by comparison, is manufactured with core diameters as small as 50 micrometers and as large as hundreds of micrometers. 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 polarization-maintaining fiber used in fiber optic sensors and fiber designed to suppress whispering gallery mode propagation. Photonic-crystal fiber
1975-559: 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 David N. Payne of the University of Southampton and Emmanuel Desurvire at Bell Labs , developed the erbium-doped fiber amplifier , which reduced the cost of long-distance fiber systems by reducing or eliminating optical-electrical-optical repeaters, in 1986 and 1987 respectively. The emerging field of photonic crystals led to
2054-564: Is immune to electrical interference as 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. Fiber cables do not conduct electricity, which makes fiber useful for protecting communications equipment in high voltage environments such as power generation facilities or applications prone to lightning strikes. The electrical isolation also prevents problems with ground loops . Because there
2133-418: Is important in fiber optic communication. 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
2212-611: Is kept in the core by the phenomenon of total internal reflection which causes the fiber to act as a waveguide . Fibers that support many propagation paths or transverse modes are called multi-mode fibers , while those that support a single mode are called single-mode fibers (SMF). Multi-mode fibers generally have a wider core diameter and are used for short-distance communication links and for applications where high power must be transmitted. Single-mode fibers are used for most communication links longer than 1,050 meters (3,440 ft). Being able to join optical fibers with low loss
2291-405: 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. Attenuation in fiber optics, also known as transmission loss,
2370-412: Is monitored and analyzed for disturbances. This return signal is digitally processed to detect disturbances and trip an alarm if an intrusion has occurred. Optical fibers are widely used as components of optical chemical sensors and optical biosensors . Optical fiber can be used to transmit power using a photovoltaic cell to convert the light into electricity. While this method of power transmission
2449-439: Is no electricity in optical cables that could potentially generate sparks, they can be used in environments where explosive fumes are present. Wiretapping (in this case, fiber tapping ) is more difficult compared to electrical connections. 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 . The refractive index
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2528-478: Is not as efficient as conventional ones, it is especially useful in situations where it is desirable not to have a metallic conductor as in the case of use near MRI machines, which produce strong magnetic fields. Other examples are for powering electronics in high-powered antenna elements and measurement devices used in high-voltage transmission equipment. Optical fibers are used as light guides in medical and other applications where bright light needs to be shone on
2607-540: Is part of a consortium – now known as Terria – that in July 2006 announced their intention to make a combined bid to build the proposed National Broadband Network . Since 2005, Optus has outsourced some customer service functions to Concentrix and 247.ai, with the outsourcer providing 800 staff operating offshore in India, supplementing Optus' 3,000-plus onshore call centre staff. Some functions have also been supplemented in
2686-493: Is responsible for providing support to Optus Business customers. CS&S works with Optus' subsidiary Alphawest to support information technology services across Optus' large business, corporate and government client base. A number of notable wholly owned subsidiaries operate as part of the Singtel Optus group. These are: Until 20 January 2013, Optus sold mobile services under the brand name Boost Mobile . Optus also has
2765-418: Is that they can, if required, provide distributed sensing over distances of up to one meter. Distributed acoustic sensing is one example of this. In contrast, highly localized measurements can be provided by integrating miniaturized sensing elements with the tip of the fiber. These can be implemented by various micro- and nanofabrication technologies, such that they do not exceed the microscopic boundary of
2844-422: Is the numerical aperture (NA) of the fiber. Fiber with a larger NA requires less precision to splice and work with than fiber with a smaller NA. The size of this acceptance cone is a function of the refractive index difference between the fiber's core and cladding. Single-mode fiber has a small NA. Fiber with large core diameter (greater than 10 micrometers) may be analyzed by geometrical optics . Such fiber
2923-474: Is the measurement of temperature inside jet engines by using a fiber to transmit radiation into a pyrometer outside the engine. Extrinsic sensors can be used in the same way to measure the internal temperature of electrical transformers , where the extreme electromagnetic fields present make other measurement techniques impossible. Extrinsic sensors measure vibration, rotation, displacement, velocity, acceleration, torque, and torsion. A solid-state version of
3002-428: 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 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
3081-484: Is typical in deployed systems. Through the use of wavelength-division multiplexing (WDM), each fiber can carry many independent channels, each using a different wavelength of light. The net data rate (data rate without overhead bytes) per fiber is the per-channel data rate reduced by the forward error correction (FEC) overhead, multiplied by the number of channels (usually up to 80 in commercial dense WDM systems as of 2008 ). For short-distance applications, such as
3160-402: Is used as a medium for telecommunication and computer networking because it is flexible and can be bundled as cables. It is especially advantageous for long-distance communications, because infrared light propagates through the fiber with much lower attenuation compared to electricity in electrical cables. This allows long distances to be spanned with few repeaters . 10 or 40 Gbit/s
3239-553: The Australian Securities Exchange on 17 November 1998. During 2001, Singtel launched a takeover bid for Cable and Wireless Optus which was ultimately successful and the company became known as Singtel Optus. In May 2004, Optus announced a $ 226.8 million bid for UEComm. The takeover was approved in July and completed in August. In July 2005, Optus announced it would acquire Alphawest Ltd. for A$ 25.9 million. The buyout
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3318-465: The DOCSIS 3.0 standard, which enabled customers to access a maximum theoretical downstream bandwidth of 100 Megabits . OptusNet is also one of the few ISPs in Australia to currently provide ADSL2+ via its own DSLAMs , which it also resells to other ISPs. Mobile network equipment is from Nortel, Nokia and Huawei and antennas are sourced from Andrews, RFS, Argus and Kathrein. The Optus network operates on
3397-462: The University of Michigan , in 1956. In the process of developing the gastroscope, Curtiss produced the first glass-clad fibers; previous optical fibers had relied on air or impractical oils and waxes as the low-index cladding material. 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
3476-405: The gain medium of a fiber laser or optical amplifier . Rare-earth-doped optical fibers can be used to provide signal amplification by splicing a short section of doped fiber into a regular (undoped) optical fiber line. The doped fiber is optically pumped with a second laser wavelength that is coupled into the line in addition to the signal wave. Both wavelengths of light are transmitted through
3555-702: The Australian population, with plans to cover 100% of Australia by 2025 through its partnership with SpaceX . Optus can trace its beginnings back to the formation of the Government-owned AUSSAT Pty Limited in 1981. In 1982, Aussat selected the Hughes 376 for their initial satellites, with the first, AUSSAT A1, launched in August 1985. AUSSAT satellites were used for both military and civilian satellite communications, and delivering television services to remote outback communities. With Aussat operating at
3634-463: The Optus Vision brand, a cable broadband arm began as a joint venture with U.S. cable and content provider Excite@Home and was known as Optus@Home from its introduction in 1999 until it was renamed in 2002. ADSL services were offered from February 2004. ADSL2+ services were provided from December 2005. In June 2007, joint venture subsidiary OPEL Networks was awarded government funding towards
3713-606: The Optus network due to legal requirements to ensure access to emergency 000 calls. Part-owned network infrastructure includes: Between 1994 and 2005 Optus had the naming rights to the Carlton football clubs original home ground in Princes Park. It was called Optus Oval until the ground was retired by the AFL in 2005. Optus was the main sponsor of the 1997 ARL season . In 2016, Optus signed
3792-523: The Philippines. Optus also uses 24/7 Inc. for telephone & chat based offshore support. In October 2006, Optus announced that it would outsource 100 contracting jobs to another Singtel subsidiary, IT company NCS , in Singapore. Optus' fully owned network infrastructure consists of the following: OptusNet also provides Cable internet. In August 2010, OptusNet released an upgrade of its HFC network to
3871-970: The Wikimedia System Administrators, please include the details below. Request from 172.68.168.226 via cp1108 cp1108, Varnish XID 763103204 Upstream caches: cp1108 int Error: 429, Too Many Requests at Fri, 29 Nov 2024 05:33:25 GMT Optical fiber An optical fiber , or optical fibre , is a flexible glass or plastic fiber that can transmit light from one end to the other. Such fibers find wide usage in fiber-optic communications , where they permit transmission over longer distances and at higher bandwidths (data transfer rates) than electrical cables. Fibers are used instead of metal wires because signals travel along them with less loss and are immune to electromagnetic interference . Fibers are also used for illumination and imaging, and are often wrapped in bundles so they may be used to carry light into, or images out of confined spaces, as in
3950-553: The attenuation in fibers available at the time was caused by impurities that could be removed, rather than by fundamental physical effects such as scattering. They correctly and systematically theorized the light-loss properties for optical fiber and pointed out the right material to use for such fibers— silica glass with high purity. This discovery earned Kao the Nobel Prize in Physics in 2009. The crucial attenuation limit of 20 dB/km
4029-416: 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 acceptance cone of the fiber. There is a maximum angle from the fiber axis at which light may enter the fiber so that it will propagate, or travel, in the core of the fiber. The sine of this maximum angle
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#17328584051704108-622: The calls would be switched to Optus' long-distance fibre optic network. In 2024, Singtel held advanced talks with Brookfield to sell a 20% stake in Optus. Brookfield and Singtel were unable to agree on terms, with Singtel claiming afterwards it remained committed to Optus and the Australian market. Key Optus products and services include: Retail services are sold to customers via phone, internet or through retail outlets, especially franchise chains such as Optus World, Network Communications, Strathfield , TeleChoice , and Allphones . Optus' Customer Solutions and Services (CS&S) organisation
4187-452: The cameras had to be supervised by someone with an appropriate security clearance. Charles K. Kao and George A. Hockham of the British company Standard Telephones and Cables (STC) were the first to promote the idea that the attenuation in optical fibers could be reduced below 20 decibels per kilometer (dB/km), making fibers a practical communication medium, in 1965. They proposed that
4266-416: The case of a fiberscope . Specially designed fibers are also used for a variety of other applications, such as fiber optic sensors and fiber lasers . Glass optical fibers are typically made by drawing , while plastic fibers can be made either by drawing or by extrusion . Optical fibers typically include a core surrounded by a transparent cladding material with a lower index of refraction . Light
4345-407: 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
4424-663: The cost of building a regional broadband network. Optus was to be contracted to build the network on behalf of OPEL. In April 2008, after a change of the Federal Government from the Liberal Party of Australia coalition to the Australian Labor Party , the new government terminated the funding agreement and the project was halted, with its functions to be replaced by the National Broadband Network . Optus
4503-442: The development in 1991 of photonic-crystal fiber , 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. 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. Optical fiber
4582-467: The difference in the index of refraction between the core and cladding materials. Rays that meet the boundary at a low angle are refracted from the core into the cladding where they terminate. The critical angle determines the acceptance angle of the fiber, often reported as a numerical aperture . A high numerical aperture allows light to propagate down the fiber in rays both close to the axis and at various angles, allowing efficient coupling of light into
4661-445: The distance from the axis. Fiber with a core diameter less than about ten times the wavelength of the propagating light cannot be modeled using geometric optics. Instead, it must be analyzed as an electromagnetic waveguide structure, according to Maxwell's equations as reduced to the electromagnetic wave equation . As an optical waveguide, the fiber supports one or more confined transverse modes by which light can propagate along
4740-621: The doped fiber, which transfers energy from the second pump wavelength to the signal wave. The process that causes the amplification is stimulated emission . 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. Conversely, fiber nonlinearity can have deleterious effects on optical signals, and measures are often required to minimize such unwanted effects. Optical fibers doped with
4819-424: The fiber tip, allowing for such applications as insertion into blood vessels via hypodermic needle. Extrinsic fiber optic sensors use an optical fiber cable , normally a multi-mode one, to transmit modulated light from either a non-fiber optical sensor—or an electronic sensor connected to an optical transmitter. A major benefit of extrinsic sensors is their ability to reach otherwise inaccessible places. An example
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#17328584051704898-404: The fiber. Fiber supporting only one mode is called single-mode . The waveguide analysis shows that the light energy in the fiber is not completely confined in the core. Instead, especially in single-mode fibers, a significant fraction of the energy in the bound mode travels in the cladding as an evanescent wave . The most common type of single-mode fiber has a core diameter of 8–10 micrometers and
4977-438: The fiber. However, this high numerical aperture increases the amount of dispersion as rays at different angles have different path lengths and therefore take different amounts of time to traverse the fiber. 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
5056-490: The first book about the new field. 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. 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
5135-408: The first in Australia. Cable & Wireless with 24.5% stakeholder bought out BellSouth 's equal 24.5% shareholding in July 1997. The company returned to profitability in 1998 and changed its name to Cable & Wireless Optus. Government relaxation of foreign ownership restrictions paved the way for the company to be floated - with Cable and Wireless increasing its holding to 52.5%) - and listed on
5214-511: The following bandwidth frequencies across Australia: The 2G GSM 900/1800 MHz network was terminated on 3 April 2017 in Western Australia and Northern Territory . 2G GSM was completely terminated on 1 August 2017 when 2G was disconnected in Victoria , New South Wales , Australian Capital Territory , Queensland , Tasmania and South Australia . To remain connected, a device that
5293-502: The guiding of light by refraction, the principle that makes fiber optics possible, in Paris in the early 1840s. John Tyndall included a demonstration of it in his public lectures in London , 12 years later. Tyndall also wrote about the property of total internal reflection in an introductory book about the nature of light in 1870: When the light passes from air into water, the refracted ray
5372-465: The gyroscope, using the interference of light, has been developed. The fiber optic gyroscope (FOG) has no moving parts and exploits the Sagnac effect to detect mechanical rotation. Common uses for fiber optic sensors include advanced intrusion detection security systems . The light is transmitted along a fiber optic sensor cable placed on a fence, pipeline, or communication cabling, and the returned signal
5451-400: The mailout campaign automatically remained as a Telstra long-distance customer. Customers who remained with Telstra could dial the override code of 1456 before the area code and phone number to manually select Optus as the carrier for that single call. Since 1 July 1998, consumers have the choice of preselecting their preferred long-distance carrier or dialling the override code before dialling
5530-413: 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. Practical applications such as close internal illumination during dentistry followed, early in the twentieth century. Image transmission through tubes was demonstrated independently by
5609-416: 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. In 1953, Dutch scientist Bram van Heel first demonstrated image transmission through bundles of optical fibers with
5688-425: The rival Foxtel consortium. Telstra's local phone network did not have the capability to deliver Foxtel pay television to consumers in the early 1990s, so Telstra identified a need to create a broadband network to support this new product. As Telstra and Optus could not agree on terms for a joint broadband cable roll out, they laid two competing cable networks, in addition to Telstra's existing copper network, at
5767-431: The roof to other parts of the building (see nonimaging optics ). Optical-fiber lamps are used for illumination in decorative applications, including signs , art , toys and artificial Christmas trees . Optical fiber is an intrinsic part of the light-transmitting concrete building product LiTraCon . Optical fiber can also be used in structural health monitoring . This type of sensor can detect stresses that may have
5846-593: The second general carrier licence in January 1991. After privatisation, AUSSAT became Optus and its first offering to the general public was to offer long-distance calls at cheaper rates than that of its competitor Telstra. The long-distance calling rates on offer were initially available by consumers dialing 1 before the area code and phone number. Following this, a ballot process was conducted by then regulator AUSTEL , with customers choosing their default long-distance carrier. Customers who made no choice or did not respond to
5925-564: The speed of manufacture to over 50 meters per second, making optical fiber cables cheaper than traditional copper ones. 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. CSELT also developed an early technique for splicing optical fibers, called Springroove. Attenuation in modern optical cables
6004-638: Was completed in November 2005 and Alphawest is now an operating division of Optus Business. On 12 January 2006, Optus acquired the remaining 74.15% of Virgin Mobile Australia for U$ 22.6 m, giving it 100% ownership. Optus Communications offered its first business-focused internet products in 1998 under the OptusNet product family, offering in-house developed dial-up and high-speed services. Optus purchased one of Australia's pioneer ISPs, Microplex, in 1998 to provide consumer dial-up internet services. Separate to this, under
6083-576: Was established by Optus in 2000 to provide wholesale business-grade DSL services under an individual brand, but today provides a collection of products only as part of the Optus Wholesale & Satellite division. XYZed established a network of DSLAMs inside Telstra telephone exchanges, utilising Unconditioned Local Loop services to reach end users. Kelly Bayer Rosmarin commenced as CEO of Optus and Consumer Australia on 1 April 2020. She resigned on 20 November 2023. These practices meant that Optus
6162-675: Was first achieved in 1970 by researchers Robert D. Maurer , Donald Keck , Peter C. Schultz , and Frank Zimar working for American glass maker Corning Glass Works . They demonstrated a fiber with 17 dB/km attenuation by doping silica glass with titanium . A few years later they produced a fiber with only 4 dB/km attenuation using germanium dioxide as the core dopant. In 1981, General Electric produced fused quartz ingots that could be drawn into strands 25 miles (40 km) long. Initially, high-quality optical fibers could only be manufactured at 2 meters per second. Chemical engineer Thomas Mensah joined Corning in 1983 and increased
6241-581: Was the largest customer of Telstra. To become competitive Optus would need to lay its own local phone network. To provide a killer application for this, the Australian Federal government sold subscription television licences. Optus, as well as the Seven Network , businessman Kerry Stokes and American cable company Cablevision, formed the Optus Vision consortium. News Corporation and Telstra created
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