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POF: Polymer Optical Fibers. Anthony Coffman Kristen Dreisig Carolyn Richmonds Megan Uhr. Agenda. Optical fiber overview POF advantages and disadvantages POF materials POF applications. Optical Fibers. Optical fiber bundle; http://www.dsm.com/en_US/images/dsmd/fiber.jpg.
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POF:Polymer Optical Fibers Anthony CoffmanKristen DreisigCarolyn RichmondsMegan Uhr
Agenda Optical fiber overview POF advantages and disadvantages POF materials POF applications
Optical Fibers Optical fiber bundle; http://www.dsm.com/en_US/images/dsmd/fiber.jpg • Flexible fibers that transport information via light • Materials • Clear glass (silica) • Polymers • Copper fibers • Composed of three concentric cylindricallayers • Core (innermost material) • Dielectric material • Specific refractive index • Cladding • Surrounds core, second dielectric material • Refractive index slightly less than core’s • Coating • Protective coating
Mechanism Cross-sectional schematic of optical fiber; www.tfhrc.gov/pubrds/julaug99/images/diagram.gif • Light enters core, bounces between core and cladding interface • Refractive index – measure of change in speed of light • Light reflects from surfaces that have indices different from surroundings • Difference in core and cladding refractive indices essential to maintaining light within fiber • Leads to total internal reflection
Processing • Co-extrusion • Cheap, high yield • Best uniformity of refractive index in axial direction • Preform Drawing Technique • Form performs by bulk polymerization of monomers in pre-drawn glass or plastic tubing • Cladding polymerized • Core polymerized inside hole within cladding
Advantages and Disadvantages Density- Polymer optical fibers are lighter than silica fibers Based on the material properties of POFs
Advantages and Disadvantages POFs have greater elasticity than silica fibers Based on the material properties of POFs:
Comparison of POF core sizes; http://127.0.0.1:4664/cache?event_id=195131&schema_id=2&q=fiber+optic&s=_Cno8R2lcam5uA2IdQBbVs5Me3s Optical fibers made of polymers can be made larger than fibers made of silica: • Greater ease of installation • Core diameters up to 100x that of silica wires • as large as 1 mm as opposed to 10 µm
Advantages and Disadvantages POFs are ductile at lower temperatures than silica fibers Based on the material properties of POFs:
Advantages and Disadvantages POFs are more sensitive to thermal effects Large, M., Polodian, L., Barton, G., Eijkenlenborg, M. Microstructured Polymer Optical Fibres Based on the material properties of POFs:
Signal attenuation and Bandwidth Suzanne R. Nagel, Thomas G. Brown, "Optical fibers", in AccessScience@McGraw-Hill • Losses of light intensity over length of cable • Caused by • Elastic scattering of light within the cable • Absorption of light by the material • Bandwidth • POF: 11 Gb/s up to 100 m • Glass: 40 Gb/s (no limitation on distance)
Cost I. Tafur Monroy et al. / Optical Fiber Technology 9 (2003) 159–171 • Materials • PMMA less expensive than glass, but higher quality polymers are more expensive • Processing • Extrusion or drawing cheap for polymers • Installation • POF cost is less due to: • Decrease in precision requirements • Connectors are much less expensive
Polymethylmethacrylate (PMMA) Olaf Ziemann, JurgenKrauser, Peter E. Zamzow, and Werner Daum. POF Handbook: Optical Short RangeTransmission Systems. Springer: Berlin, 2008. Most common POF material—affordable and performs well Chemically resistant to water, alkalines, dilute acids, and hydrocarbons Transparent due to amorphous structure C-H single bonds lead to signal attenuation; heavier atoms reduce this effect (D, F most commonly substituted) Can be crosslinked for high temperature applications (T > Tg= 115 ˚C), but losses increase
Deuterated Polymers • Attenuation is typically an order of magnitude less • H’s can replace D’s in polymer structure over time as water vapor is absorbed by the fiber. http://upload.wikimedia.org/wikipedia/commons/thumb/1/15/Hydrogen_Deuterium_Tritium_Nuclei_Schematic.svg/800px-Hydrogen_Deuterium_Tritium_Nuclei_Schematic.svg.png Deuterium (D) has twice the mass of a normal hydrogen (H) atom Replacing H’s in polymer structure with D’s results in chemically similar polymer
Fluorinated Polymers Polytetrafluoroethylene (Teflon®); http://pslc.ws/macrog/images/vinyl07.gif Fluorine (F) has greater mass than both H and D, allowing for lower attenuation, theoretically approaching that of silica glass fibers Fluorinated polymers (such as polytetrafluoroethylene or Teflon®) typically form crystalline structures Random copolymers result in the least amount of crystallization
Fluorinated Polymers CYTOP®; Olaf Ziemann, JurgenKrauser, Peter E. Zamzow, and Werner Daum. POF Handbook: Optical Short RangeTransmissionSystems. Springer: Berlin, 2008. Most promising is Cyclic Transparent Optical Polymer (CYTOP®) Produced by Japanese company Asahi Glass Lowest attenuation values result, as there are no H’s Attenuation values allow for penetration into silica fiber market
Applications • Two main advantages • Cheap • Robust • Three application categories • Lighting • Communications • Sensors
Lighting Decorative lamp (http://www.ed-nightlight.com/fiber%20optic%20lamp.htm);Endoscope tip (http://www.invendo-medical.de/e407/index_eng.html); Pool lighting (http://www.gardenstructure.com/low_voltage_lighting_gta_toronto_lighting_designer.html) • Decoration – lamps and pools • Inspection of mechanical welds in pipes and engines (airplanes, rockets, automobiles) • Medical applications • Endoscopes, bronchoscopes, laparoscopes
Communications Triple play – high-speed internet access, television, and telephone in one broadband connection;http://blog.bycoddot.com/2007/04/ • Research conducted to reduce attenuation and increase bandwidth • Ideal for short distance network cabling • New standard for LAN cabling • Material cost falls between copper and glass • Ease of installation and lower cost than copper or glass • With aging, signaldeformation observedin UV/blue light region
Communications Jeep navigation system; http://www.blogcdn.com/www.engadget.com/media/2009/04/garmin-chrysler-04-08-09.jpg • HSPN (High Speed Plastic Network) • Established by the government to develop graded index POF and bring them to the aerospace, automotive, and datacomms marketplace • Currently usage in car electronic networks (entertainment, navigation systems; tire, engine sensors)
Sensors • Optical measurement of flow, biofilm growth, toxicity, rotation, humidity, fluorescence • Humidity • POF with PVA film • Oil-insulated power equipment • Toxicity biosensors • The fluorescein produced by biological reaction is collected and transmitted by POF • Increase in fluorescent intensity indicates increase in toxicity of cell environment
Conclusions POFs are inexpensive alternative to silica fibers and copper cabling Many polymers being developed to improve performance Future applications include widespread use in LAN and automotive data wiring