Monomode triangular index fiber excitation through upside down tapered cylindrical microlens on its end face: study of coupling in the presence of mechanical offsets
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Anirban Lahiri
Abstract
The analytical evaluation of the coupling optics, taking care of lateral and angular offsets, has been presented for an upside-down tapered cylindrical microlensed (UDTCM) single-mode circular core triangular index fiber (TIF) excited by laser diode (LD). ABCD matrix appropriate for this system in the transverse plane is being used in order to derive analytical formulae of coupling efficiencies (CE) in presence of the said kinds of mechanical offsets. Distribution of fields of both the LD and TIF are taken to be Gaussian type. This study employs two wavelengths 1.3 µm and 1.5 µm and three TIFs of different V numbers. Using the prescribed formulae, the concerned prediction involves little computation. This paper highlights the tolerance of the coupler with respect to the said types of mechanical offsets. The outcomes concerned with UDTCM will be helpful for optical packages.
Acknowledgments
The authors are indebted to the Brainware University, West Bengal, India, for the necessary support.
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Research ethics: Research ethics are followed throughout the manuscript.
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Informed consent: Not applicable.
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Author contributions: The authors have accepted responsibility for the entire content of this manuscript and approved its submission.
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Use of Large Language Models, AI and Machine Learning Tools: None declared.
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Conflict of interest: The authors state no conflict of interest.
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Research funding: None declared.
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Data availability: MATLAB has generated the data, which can be obtained at the request of the corresponding author.
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