Dissertation > Excellent graduate degree dissertation topics show

Effects of Twisting and Bending on LP21 Mode Propagation in Optical Fiber Based on Coupled Mode Theory

Author: YuanYuFeng
Tutor: WuXingKun
School: Zhejiang University
Course: Optical Engineering
Keywords: Fiber mode Fiber sensor LP21 mode Fiber mode theory Elastic-optic effect Coupled mode theory Fiber twist Fiber bend Fiber specklegram sensor
CLC: TN253
Type: Master's thesis
Year: 2012
Downloads: 83
Quote: 0
Read: Download Dissertation

Abstract


Fiber takes an important place in the area of the modern communication and sensors. People insist on the fiber research from the 1960s’.Low-order multimodes (few-mode) in optical fiber have different characteristics. This paper makes the focus on the effects of twisting and bending on LP21 mode propagation in optical fiber which is one of the low-order multimodes. Twisting and bending characteristics of LP21 mode propagation is presented for the first time. Theoretical fiber mode modeling, combining geometrical rotation with opto-elastic effects, demonstrates that the propagation of LP21 mode is bending-effect-immune. Experimental testing verifies that the LP21 mode specklegram rotates 0.9112 of the fiber twist angle in a fused silica fiber, independent of any fiber bending. This characteristic allows for LP21 mode to be highly applicable in fiber specklegram sensors (FSS).Strict theoretical analysis and three experiment setups are discussed in this paper including following parts:Firstly, the fiber mode theory and the coupled mode theory are introduced: common fiber modes with excitation conditions, principle of the coupled mode theory with its application on the polarization optics of twisted single-mode fibers and the fiber specklegram sensors.Secondly, the theory of the twist and bend characteristic of fiber LP21 mode is shown including:the equation of the LP21 mode, the elastic-optic equation, the equation of the coupled mode theory on the LP21 mode and the whole calculation process about the equation in the Maple soft.Thirdly, this paper shows three experimental platforms about the fiber twist, the fiber bend and the mid-fiber twist. Also the data collection method will be discussed.Fourthly, this paper will present the data analysis methods and the software fitting. Further more, the application of the LP21 mode will be put in this part.Lastly, this paper shows the research in the twist and bend characteristic of LP21 mode with important meaning in the fiber mode research and widely application.

Related Dissertations

  1. Research of Pernicious Gases Measurement Technique Based on Algorithm of Integrating Sphere,TP274
  2. Study & Design of the Interferometric PCF Grating Sensor,TN253
  3. Research on Double Light Path Distributed Optical Fiber Temperature Sensing System Based on Brillouin Scattering,TP212.1
  4. Based on Brillouin scattering distributed sensing key technologies,TP212.14
  5. Research in the Physical Features of Adjustable Micro-Strured Fiber Bragg Grating,TN253
  6. Study of Band-pass Filter for the All Fiber Interconnection Between Multimode Fiber and Single Mode Fiber Network,TN713.5
  7. Study on the Coupling and Temperature Sensing Characteristics of Dual-core Photonic Crystal Fibers,TN253
  8. Research on the Polarization Error and Key Component of Optical Fiber Gyroscope,TN253
  9. Fiber Optic AE Sensing System Research and Application,TN253
  10. Study on Multiplexing Demodulation System of Fiber Bragg Grating,TN253
  11. Study on Optical Add-drop Multiplexing Based on FBG in WDM Systems,TN253
  12. The Design and Simulation of Two Dimension Four Channel Photonic Crystal Filter,TN713
  13. Design and Study of Highly Efficient Photonic Crystal Beam Splitters,TN25
  14. Researches on the Stability and Temperature Resolution Enhancement of Distributed Optical Fiber Temperature Sensor,TP212.11
  15. Routing and Positioning Algorithms in Hybrid Sensor Networks,TP212.9
  16. The Design and Realization of Dam Monitoring Software System,TP311.52
  17. Chiral optical characteristics of the nonlinear coupling,TN253
  18. Fabrication and Characteristics of Multipeaks Resonant Fiber Gratings by Femtosecond Laser Pulses,TN253
  19. Investigation on Optical Fiber Sensor Fabricated by Femtosecond Laser,TN249
  20. Composite Cavity Fiber Laser and Its Sensing Applications,TP212.14
  21. DFB Fiber Laser Sensors,TN248

CLC: > Industrial Technology > Radio electronics, telecommunications technology > Photonics technology,laser technology > Optical waveguide and integrated optics > Fiber optic components
© 2012 www.DissertationTopic.Net  Mobile