Category: Fiber Patch Cord

How Great Of Fiber Optic Cables

Fiber optic cables are used frequently for today’s telecommunication network because of their high bandwidth, high reliability and relatively low cost. For a layman, fiber optical cable or FOCs as they are often called, is a plastic or glass fiber which permits the transmission of communications over large distances and at higher rates. They present wire almost superfluous, because they pass the same, but there are a lot of loss. These cables are unique because they are not affected by electromagnetic interference. Use these cables in performing image used in the fiber.

Each cable can not beyond the permissible limit. Fiber optic cable is very safe and more reliable than the traditional copper wire. Most of these cable to work in high-pressure environments. A fiber optic cable assembly includes a tube, a track and fasteners in addition to the conventional fiber bundles.

The cable tubes have both front and rear surfaces to it. These cables operate with the help of photons. These photos are transmitted to a second quantum dot which is placed between mirrors. These mirrors absorb the photons and bounce them back to the quantum dot until it absorbs it.

The fiber optic cables are used for carrying different services pertaining to data, voice, cable TV, and video. The fiber optic cables keeps the electronic equipments far away from environment that are subjected to high temperature, stem, dust, smoke and so on. The unique feature of these fiber optic cable is that stainless steel lens and fiber cables can be easily replaced without any further calibration.

For the installation of fiber optic cables, fiber optic cable blowers are designed. The unique feature of these fiber optic is that they carry information in the form of light. These cables are very useful in transporting both audio and video signals over short and long distances. If a fiber optic cable is broken, another cable has to be fitted in between the connectors rather than soldering or twisting them. Fiber optic technologies have found its place in many applications. They are widely used in telecommunications, CCTV security places, and local area networks and so on.

Glass fibers are made use of for fiber optic cabling. They hardly provide any change in the signals they carry over long distances. Engineers found that by adding some additional chemicals into the existing silica, they can change the properties of the glass used for the cable (glass fiber cable). Althouth, both glass and plastic can be used in the manufacture of cable, glass is the preferred one used in the manufacture of cable, used for long distance transmission communication. The purpose of glasses in total internal reflection transmission.

A fiber optic cable consists of a core which is made of glass silica. Through this core, the light is guided. The core is covered with a material whose refractive index is slightly lower than that of the core. Two optical fibers are connected via mechanical splicing or fusion splicing. This process involves lots of skills as microscopic precision is required to align them.

Regardless of the application used in optical fiber, they will stay here. Their unique features and capabilities, to ensure that they will continue to spread widely used in communications industry for many years.

SC fiber optic connector basic structure

More than a dozen types of fiber optic connectors have been developed by various manufacturers since 1980s. Although the mechanical design varies a lot among different connector types, the most common elements in a fiber connector can be summarized in the following picture. The example shown is a SC connector which was developed by NTT (Nippon Telegraph and Telephone) of Japan.

SC Connector

A SC Connector Sample

sc connector
SC Connector Structure

Elements in a SC connector

1. The fiber ferrule.

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SC Connector Fiber Ferrule

SC connector is built around a long cylindrical 2.5mm diameter ferrule, made of ceramic (zirconia) or metal (stainless alloy). A 124~127um diameter high precision hole is drilled in the center of the ferrule, where stripped bare fiber is inserted through and usually bonded by epoxy or adhesive. The end of the fiber is at the end of the ferrule, where it typically is polished smooth.

2. The connector sub-assembly body.

The ferrule is then assembled in the SC sub-assembly body which has mechanisms to hold the cable and fiber in place. The end of the ferrule protrudes out of the sub-assembly body to mate with another SC connector inside a mating sleeve (also called adapter or coupler).

3. The connector housing

Connector sub-assembly body is then assembled together with the connector housing. Connector housing provides the mechanism for snapping into a mating sleeve (adapter) and hold the connector in place.

4. The fiber cable

Fiber cable and strength member (aramid yarn or Kevlar) are crimped onto the connector sub-assembly body with a crimp eyelet. This provides the strength for mechanical handing of the connector without putting stress on the fiber itself.

5. The stress relief boot.

Stress relief boot covers the joint between connector body and fiber cable and protects fiber cable from mechanical damage. Stress relief boot designs are different for 900um tight buffered fiber and 1.6mm~3mm fiber cable.

How are Optic Fiber Made?

Many People ask how fiber optics are made. You can’t just use “regular” glass. If you were to make optical fiber from ordinary window glass, the light that you shine through it would have a difficult time traveling more than a few kilometers, let alone the distances necessary for long distance transmission. That’s because ordinary glass contains distortions, discolorations and other impurities that would quickly absorb, reflect, or otherwise disperse light long before it could travel any great distance.

In contrast, because optical fiber is actually made from very pure glass, the light traverses great distances largely unimpeded by impurities and distortions.

Fiber Optic Cable – Light How it Works

To transmit light effectively, fiber optic cable must contain glass of the highest purity. The process of making glass with this level of purity is very demanding, requiring careful control over the materials and processes involved. Yet, the fundamental concept is simple. Essentially, optical fiber is made from drawing molten fiber from a heated glass blank or “preform.” The following provides a more detailed explanation of the three basic steps involved in making optical fiber.

Step #1

Create the Fiber Optic Preform

A preform is a cylindrical glass blank that provides the source material from optic fiberwhich the glass fiber will be drawn in a single, continuous strand.

Making a preform involves a chemical process known as Modified Chemical Vapor Deposition (MCVD). This process involves bubbling oxygen through various chemical solutions including germanium chloride (GeC14) and silicon chloride (SiC14).

The bubbling chemicals produce gas that is directed into a hollow, rotating tube made of synthetic silica or quartz.  A torch is moved up and down the rotating tube, resulting in very high temperatures that cause the gas to react with oxygen to form silicon dioxide (Si02) and germanium dioxide (Ge02). These two chemicals adhere to the inside of the rotating tube where they fuse together to form extremely pure glass.

Creating the preform takes several hours, after which additional time is required for the glass blank to cool.  Once cooled, the glass is tested to ensure that it meets quality standards, especially in terms of index of refraction.

Step #2 

Draw Optical Fiber from the Preform

In this step, the finished glass preform is installed at the top of a tower which supports various devices used in the fiber drawing process.

The process begins by lowering one end of the preform into an in-line furnace that produces heat in a range of 3,400 to 4,000 degrees Fahrenheit. As the lower end of the preform begins to melt, it forms a molten glob that is pulled downward by gravity.  Trailing behind the glob is a thin strand of glass that cools and solidifies quickly.

The equipment operator threads this glass strand through the remainder of the devices on the tower, which include a number of buffer coating applicators and ultraviolet curing ovens. Finally, the operator connects the fiber to a tractor mechanism.

The tractor device pulls the glass strand from the preform at a rate of 33 to 66 feet per second.  The actual speed at which the tractor pulls the strand is dependent upon the feedback information the device receives from a laser micrometer that continually measures the fiber’s diameter.

At the end of the run, the completed fiber is wound onto a spool.

Step # 3 

Test the Fiber Optics

The completed optical fiber must undergo a number of tests to determine the quality of the finished product.  The following are a few of the assessments involved:

• Refractive index profile

• Fiber geometry inspection, including core, cladding and coating

• Tensile strength • Bandwidth capacity

• Attenuation at different wavelengths

• Chromatic dispersion

• Operating temperature and humidity range

 

Quality Control in Optical Fiber Production

Various factors influence the quality and purity of the optical fiber produced.  These include:   Chemical Composition – Achieving optimal ratios of the various chemicals used to create the preform is important for achieving glass purity.  This mixture of chemicals also determines the optical properties of the fiber that will be produced from the preform, including coefficient of expansion, index of refraction, and so forth.   Gas Monitoring – It is crucial that the gas composition and rate of flow be monitored throughout the process of creating the preform.  It is also important that any valves, tubes and pipes that come into contact with the gas be made of corrosion-resistant materials.

Heat and Rotation – The hollow cylinder that is used to create the preform must be heated at the proper temperature and continually rotated to enable the chemicals to be deposited evenly.

Application of optical communication is still broad prospects

Once the Nortel global leader in fiber optic communications during the Internet bubble in 2000, the money in the acquisition of a large number of optical communications research and the production of small and medium enterprises, the industry has been criticized in the subsequent bankruptcy of Nortel. In fact, Nortel grasp of technology trends, the direction is right, unfortunately, Nortel too hasty, global demand for optical communication was not to such an extent.

But now the situation is very different compared with around 2000. The rapid development of mobile Internet and the widespread popularity of smart mobile terminal equipment, being a huge challenge to the global telecommunications network capacity, transmission speed. The era of “data flood peak to optical communication technology has always been known by the transmission bit of new development opportunities and a huge space. Optical communication technology not only did not fall behind, the contrary, the optical communication industry chain, from fiber optic cable system equipment, terminal equipment to optical devices, a critical period in the comprehensive technology upgrade.

The field of optical communication is a noteworthy event, the National Development and Reform Commission recently organizing the preparation of strategic emerging industries key products and services Guidance Catalogue, which in conjunction with the relevant departments, the optical communication technology and product responsibility and selected emerging industries of strategic focus products.

In fiber optics, including FTTx G.657 optical fiber, broadband long-distance high speed large capacity optical fiber transmission with G.656 optical fiber, photonic crystal fiber, rare earth doped fiber (including ytterbium doped fiber, erbium doped fiber and thulium doped fiber, etc.) the laser energy transmission fiber, and has some special properties of new optical fiber, plastic optical fiber, polymer optical fiber is fully finalists. The upgrade of the fiber optic technology, will bring the data transmission capacity, distance, quality leap.

In the field of fiber access equipment, passive optical network (PON), wavelength division multiplexer (WDM),OLT and ONU on the list. Optical transmission equipment, especially the line rate of 40 Gbit/s, 100Gbit/s large capacity (1.6Tb/s and abobe) DWDM equipment, reconfigurable optical bifurcation Multiplexer (ROADM) wavelength division multiplexing system ran cross-connect (OXC) equipment, large-capacity high-speed OTN optical transport network equipment as well as packetized enhanced OTN equipment, PTN packet transport network equipment also impressively. These products are “broadband China” works to promote a powerful weapon; both long-distance backbone network, metropolitan area network or access network even close to the user’s “last mile” of these products will come in handy.

The major products are classified as strategic emerging industries in the field of optical devices, high-speed optical components (active and passive). This is the core and foundation of the field of optical communication technology, device development, the improvement of integration, function enhancement can bring significantly reduce the cost of system equipment and provide a performance boost.

At the same time, the annual OFC / NFOEC (fiber-optic communications exhibition) will be held in late March in California. This event will showcase the latest technology and research progress of the global optical component modules, systems, networks and fiber optic products, represents a new trend of development of optical communication technology.

100G for ultra-high-speed network technology is the current OFC hot one. 2012 100G technology on a global scale backbone network level scale application of 100G optical network applications will rapidly expand with the 100G device further mature. In the same time, the industry has also increased efforts to develop the 100G optical modules, silicon photonics technology pluggable multi-source agreement 100G CFP MSA CPAK optical module has been available. Outside the backbone network, 100G MAN application is the current one of OFC discussion topic.

The rise of cloud computing brings data center construction boom, 100G technology in the data center is a popular data center for high-speed pluggable optical devices is also a hot topic. Experts believe that photonic technology has a key role to play in the large enterprise data centers, but this is only a start, the size of the new cloud computing data center such as a warehouse, with more than 100,000 servers carrying the computing and storage resources, the required network bandwidth than PB level. These data centers only optical communications technology in order to achieve VCSEL (vertical cavity surface emitting lasers) and multi-mode fiber has played an important role, and will continue to introduce new fiber optic communication technology.