Fiber Optic Basic Training 2

• TO PROVIDE YOU WITH THE TOOLS YOU NEED TO LEARN, THE ASPECTS OF FIBER OPTIC THEORY, HOW IT WORKS, BRIEF HISTORY, USES, COMMON TYPES OF CABLE AND CONNECTORS, HARDWARE, CABLE TERMINATION, POLISHING, INSERTION LOSS AND TESTING.

Total Internal reflection is the basic idea of fiber optic

• 1870: An Irish physicist called John Tyndall (1820–1893) demonstrated internal reflection at London's Royal Society. • 1930s: Heinrich Lamm and Walter Gerlach, two German students, tried to use light pipes to make a gastroscope—an instrument for looking inside someone's stomach.

• 1950s: In London, England, Indian physicist Narinder Kapany (1927–) and British physicist Harold Hopkins (1918– 1994) managed to send a simple picture down a light pipe made from thousands of glass fibers.

• 1957: Three American scientists at the University of Michigan, Lawrence Curtiss, Basil Hirschowitz, and Wilbur Peters, successfully used fiber-optic technology to make the world's first gastroscope. • 1960s: Chinese-born US physicist Charles Kao (1933–) and his colleague George Hockham realized that impure glass was no use for longrange fiber optics. Kao suggested that a fiber-optic cable made from very pure glass would be able to carry telephone signals over much longer distances and was awarded the 2009 Nobel Prize in Physics for this ground-breaking discovery.

• 1960s: Researchers at the Corning Glass Company made the first fiber-optic cable capable of carrying telephone signals. • 1970: Donald Keck and colleagues at Corning found ways to send signals much further (with less loss) prompting the development of the first low-loss optical fibers.

• 1977: The first fiber-optic telephone cable was laid between Long Beach and Artesia, California. • 1997: A huge transatlantic fiber-optic telephone cable called FLAG (Fiber-optic Link Around the Globe) was laid between London, England and Tokyo, Japan.

• A fiber optic is a flexible and a transparent fiber, which is made by drawing glass (silica) or plastic. • Fiber optics have diameter slightly thicker that that of human hair.

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Usually, a fiber optic communication system consists of three main components: optical transmitter, fiber optic cable and an optical receiver. The optical transmitter converts electrical signal to optical signal; the fiber optic cable carries the optical signal from the optical transmitter to the optical receiver; and the optical receiver reconverts the optical signal to electrical signal. The most commonly used optical transmitter is semiconductor devices like LEDs (light-emitting diodes) and laser diodes. Photodetector is the key part of an optical receiver. It converts light into electricity using photodetector effect. As for the fiber optic cable, there is too much to say. As the use and demand for speed and bandwidth, the development of optical cables is amazing. Now in the optical cable market, there are OS2 fIber , OM1 fIber, OM2 fIber, OM3 fIber, OM4 fiber and OM5 fiber cable for different optical applications. Optical fibers are used as a medium for telecommunication and networking because it is flexible and can be bundled as cables. It is especially advantageous for long-distance communications, because light propagates through the fiber with little attenuation compared to electrical copper cables. The figure below shows that all fiber optic transmission systems use modulated light to convey information from a transmitter to a companion receiver.

• A fiber optic data link sends input data through fiber optic components and provides this data as output information. It has the following three basic functions: • To convert an electrical input signal to an optical signal • To send the optical signal over an optical fiber • To convert the optical signal back to an electrical signal A fiber optic data link consists of three parts - transmitter, optical fiber, and receiver. Figure 1 is an illustration of a fiber optic data-link connection. The transmitter, optical fiber, and receiver perform the basic functions of the fiber optic data link. Each part of the data link is responsible for the successful transfer of the data signal. A fiber optic data link needs a transmitter that can effectively convert an electrical input signal to an optical signal and launch the datacontaining light down the optical fiber. A fiber optic data link also needs a receiver that can effectively transform this optical signal back into its original form. This means that the electrical signal provided as data output should exactly match the electrical signal provided as data input.

• https://www.blackbox.co.uk/gbgb/page/27222/Resources/TechnicalResources/black-box-explains/Fibre-OpticCable/Fibre-optic-cable-construction • https://store.cablesplususa.com/fiberoptic-cable-construction.html • http://www.cables-solutions.com/threecommon-types-of-fiber-optic-cables.html

CORE • The fiber core is made of silica glass and is the central part of the fiber optic cable that carries the light signal. • They are hair-thin in size and the diameter of the fiber core is typically 8 µm for single mode fiber, and 50 µm or 62.5 µm for multi mode fiber.

CLADDING

• The cladding is also made of glass, and is the layer that surrounds the fiber core. • Together, they form a single solid fiber of glass that is used for the light transmission. The diameter of the cladding is typically 125 µm.

PRIMARY COATING • Also known as the primary buffer. • This layer provides protection to the fiber core and cladding. • They are made of plastic and only provide mechanical protection. • They do not interfere with the light transmission of the core and the cladding.

STRENGTHENING FIBERS

• They are strands of aramid yarn, or better known as Kevlar. • They are added to the fiber optic cable to prevent the breakage of the fiber glass during installation.

CABLE JACKET • The last layer is the cable jacket, which are comprised of different materials depending on the choice of the end user and the application in use. • Like the primary coating, they serve only as a mechanical protection to the fiber core and cladding inside.

Common types of fiber optic cable jacket ratings are: • OFNP (Optical Plenum)

Fiber,

Nonconductive,

• OFNR (Optical Fiber, Nonconductive, Riser)

• LSZH (Low Smoke Zero Halogen)

• LOOSE-TUBE CABLES

• TIGHT-BUFFERED CABLES

 In loose tube cables, color-coded plastic buffer tubes house and protect optical fibers, a gel filling compound impedes water penetration.  The main feature is that the fiber is available to be freely moved.

 This is beneficial as there is less strain and allows fiber to expand and contract with respect to the changes in temperature.  In addition, they have better bending performances as the fiber inside can wander inside the loose tube cable.

 Finally, they are also beneficial during installation where they can be stretched more without stressing the optical fiber.

• In contrast to loose-tube cables, tight buffered cables have the buffering material in direct contact with the fiber and tightly wraps around the optical fiber.

• They provide a rugged cable structure for better mechanical protection of fibers during handling and installation. • The strength members or aramid yarn Kevlar are placed either after the outer cable jacket or around each individual fiber optic jacket, often referred to sub jackets.

• Single-mode Step-index Fiber Cable • Multimode Step-index Fiber Cable, • Multimode Graded-index Fiber

• Sometimes called a single-mode fiber cable, • Single-mode fiber cables have extremely small core diameters, ranging from 5 to 9.5 um. • The core is surrounded by a standard cladding diameter of 125 um. The jacket is applied on the cladding to provide mechanical protection, are made of one type of polymer in different colors for color-coding purposes.

• Single-mode fibers have the potential to carry signals for long distances with low loss, and are mainly used in communication systems. • Single-mode operation begins when the wavelength approaches the core diameter.

Sometimes called a multimode fiber cable. Multimode fiber cables have bigger diameters than the single-mode, with core diameters ranging from 100 to 970 um. They are available as glass fibers (a glass core and glass cladding), plastic-class silica (a glass core and plastic cladding), and plastic fibers (a plastic core and cladding).

They are also the widest ranging, although not the most efficient in long distances, and they experience higher losses than the singlemode fiber cables. Multimode fiber cables have the potential to carry signals for moderate and long distance with low loss (when optical amplifiers are used to boost the signals to the required power).

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Sometimes called graded-index fiber cables (GRIN). Graded-index and multimode fiber cables have similar diameters. Common graded-index fibers have core diameters of 50,62.5, or 85 um, with a cladding diameter of 125 um. The core consist of numerous concentric layers of glass, somewhat like the annular rings of a tree or a piece of onion. Each successive layer expanding outward from the central axis of the core until the inner diameter of the cladding has a lower index of refrection. Light travels faster in an optical material that has a lower index of refraction. Thus, the further the light is from the centre axis, the greater its speed. This type of fiber optic cable is popular in applications that require a wide range of wavelenths, in particular telecommunication, scanning, imaging, and data processing stystems. In particular telecommunication, Multimode OM4 fiber optic cable is used in any data center looking for high speeds of 10G or even 40G or 100G. OM4 multimode fiber are ideal for using in many applications such as Local Area Networks (LAN) backbones, Storage Area Networks (SAN), Data Centers and Central Offices.

Extremely High Bandwidth Longer Distance Resistance to Electromagnetic Interference Low Security Risk Small Size Light Weight Low Power Loss Interference

Fragility Difficult to Install Attenuation & Dispersion Cost Is Higher Than Copper Cable Difficult to Splice Special Equipment Is Often Required Highly Susceptible Can’t Be Curved

• https://www.fs.com/the-advantages-anddisadvantages-of-fiber-optictransmission-aid-431.html • https://www.linkedin.com/pulse/whatadvantages-disadvantages-optical-fibercable-max-liao

Internet Cable Television Telephone Computer Networking Surgery and Dentistry Lighting and Decorations Mechanical Inspections Military and Space Applications Automotive Industry

• 1. Fusion Splicing Method • 2. Mechanical Splicing Method

• Fusion splicing is a permanent connection of two or more optical fibers by welding them together using an electronic arc. It is the most widely used method of splicing as it provides for the lowest loss, less reflectance, strongest and most reliable joint between two fibers. When adopting this method, fusion splicing machines are often used. Generally, there are four basic steps in fusion splicing process as illustrating in following one by one.

• A mechanical splice is a junction of two or more optical fibers that are aligned and held in place by a self-contained assembly. A typical example of this method is the use of connectors to link fibers. This method is most popular for fast, temporary restoration or for splicing multimode fibers in a premises installation. Like fusion splice, there are also four basic steps in mechanical splice.

• https://www.electronicsnotes.com/articles/connectivity/fibreoptics/fibre-splicing.php\ • http://www.fiber-opticsolutions.com/fiber-opticsplicing%EF%BC%9Atwo-methods.html

• Which Method is Better? • Both fusion splicing and mechanical splicing method have their advantages and disadvantages. Whether choosing fusion splice or mechanical splice depends on the applications. • The fusion one provides a lower level of loss and a higher degree of permanence than mechanical splicing. However, this method requires the use of the expensive fusion splicing equipment. In view of this, fusion splice tends to be used for the long high data rate lines that are installed that are unlikely to be changed once installed. • The mechanical splicing is used for applications where splices need to be made very quickly and where the expensive equipment for fusion splices may not be available. Some mechanical fiber optic splice easily allows both connection and disconnection. In this way, a mechanical splice may be used in applications where the splice may be less permanent.

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trip fiber cable jacket. Strip back about 3 meters of fiber cable jacket to expose the fiber loose tubes or tight buffered fibers. Use cable rip cord to cut through the fiber jacket. Then carefully peel back the jacket and expose the insides. Cut off the excess jacket. Clean off all cable gel with cable gel remover. Separate the fiber loose tubes and buffers by carefully cutting away any yarn or sheath. Leave enough of the strength member to properly secure the cable in the splice enclose. Strip fiber tubes. For a loose tube fiber cable, strip away about 2 meters of fiber tube using a buffer tube stripper and expose the individual fibers. Clean cable gel. Carefully clean all fibers in the loose tube of any filling gel with cable gel remover. Secure cable tubes. Secure the end of the loose tube to the splice tray and lay out cleaned and separated fibers on the table. Strip and clean the other cable tube’s fiber that is to be spliced, and secure to the splice tray. Strip first splicing fiber. Hold the first splicing fiber and remove the 250um fiber coating to expose 5cm of 125um bare fiber cladding with fiber coating stripper tool. For tight buffered fibers, remove 5cm of 900um tight buffer first with a buffer stripping tool, and then remove the 5cm of 250um coating. Place the fusion splice protection sleeve. Put a fusion splice protection sleeve onto the fiber being spliced. Clean the bare fiber. Carefully clean the stripped bare fiber with lint-free wipes soaked in isopropyl alcohol. After cleaning, prevent the fiber from touching anything. Fiber cleaving. With a high precision fiber cleaver, cleave the fiber to a specified length according to your fusion splicer’s manual. Prepare second fiber being spliced. Strip, clean and cleave the other fiber to be spliced. Fusion splicing. Place both fibers in the fusion splicer and do the fusion splice according to its manual. Heat shrink the fusion splice protection sleeve. Slide the fusion splice protection sleeve on the joint and put it into the heat shrink oven, and press the heat button. Place splice into splice tray. Carefully place the finished splice into the splice tray and loop excess fiber around its guides. Ensure that the fiber’s minimum bending radius is not compromised. Perform OTDR test. Perform a OTDR test of the splice and redo the splice if necessary. Close the splice tray. After all fibers have been spliced, carefully close the splice tray and place it into the splice enclosure. Bidirectional OTDR test (or power meter test). Test the splices with an OTDR or power meter from both directions. Mount the splice enclosure. Close and mount the splice enclosure if all splices meet the specifications. https://www.fiberoptics4sale.com/blogs/archive-posts/95149894-fiber-optic-cable-splicing

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Cleaver Wipes+ fixed length device Visual fault locator Alcohol bottle Fiber stripper Optical power meter Drop cable slitter Armored cable slitter optical light source Optical fusion splicer AV6471