COUPLING EFFICIENCY FOR SINGLE MODE FIBERS AND FIBER-OPTIC ALIGNMENT
AUTOMATION
A PRESENTATION BY:
Shubham [email protected]
• Gaussian Beam analysis
• Losses (Intrinsic and Extrinsic)
• Mechanical misalignments (Lateral, Longitudinal and Angular)
• Fiber-optic alignment automation
• Hill-climbing algorithm
• Drawbacks of hill-climbing algorithm
• A proposed novel feed-forward controlling algorithm
• Conclusion
Overview
Gaussian Beam
Source wave function Modal wave function
Coupling Efficiency
= =
Total efficiency
Power- Coupling efficiency
Source Efficiency
Coupling Efficiency Contd.
Losses
LOSS
Intrinsic losses
• NA effects
• Fiber-radius effects
• Index-Profile effects
• Core concentricity within cladding
• Fabrication tolerances
Extrinsic losses
• Lateral Misalignment
• Longitudinal Misalignment
• Angular Misalignment
Reflection losses
Longitudinal Misalignment
Angular Misalignment
Lateral Misalignment
Current technology
6 DEGREES OF FREEDOM
Array Waveguide Grating PLC
Fiber-Fiber Alignment Automation
Drawbacks of Hill-Climbing
Cutting off at Local Maxima
Hill climbing Vs Smart Algorithm
Hill climbing algorithm
Smart Algorithm
Smart Algorithm
Conclusion
• Longitudinal misalignment is less critical than angular and lateral misalignment.
• Dominant loss arises from lateral displacement in single mode fibers.
• Hill-climbing algorithm is time-consuming and has the potential drawback of missing the actual peak.
• A novel Algorithm using a feed forward controlling technique is proposed which takes care of the disadvantages of hill climbing method.