COUPLING EFFICIENCY FOR SINGLE MODE FIBERS AND FIBER-OPTIC ALIGNMENT

AUTOMATION

A PRESENTATION BY:

Shubham Bhatskb25@drexel.edu

• 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.