Robust method for finding the modes in a fibre with an unknown refractive index profile
The result's identifiers
Result code in IS VaVaI
<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F68081731%3A_____%2F22%3A00559492" target="_blank" >RIV/68081731:_____/22:00559492 - isvavai.cz</a>
Result on the web
<a href="https://www.spiedigitallibrary.org/conference-proceedings-of-spie/12140/121400M/Robust-method-for-finding-the-modes-in-a-fibre-with/10.1117/12.2632808.short" target="_blank" >https://www.spiedigitallibrary.org/conference-proceedings-of-spie/12140/121400M/Robust-method-for-finding-the-modes-in-a-fibre-with/10.1117/12.2632808.short</a>
DOI - Digital Object Identifier
<a href="http://dx.doi.org/10.1117/12.2632808" target="_blank" >10.1117/12.2632808</a>
Alternative languages
Result language
angličtina
Original language name
Robust method for finding the modes in a fibre with an unknown refractive index profile
Original language description
The number of eigenmodes in an optical fibre depends on the wavelength of the excitation laser beam as well as on the exact geometry and refractive index profile of the fibre. The latter is often proprietary information and, when available, is only specified to within manufacturing tolerances. We here present a method for obtaining the number of fibre modes, as well as their shape, which requires no knowledge about the fibre, save a very approximate core radius. The method is based on the singular value decomposition (SVD) of a set of speckle patterns, measured at the output end of the fiber, which is then expanded onto a set of orthonormal basis functions. We present two possible approaches for the field expansion, where the first approach uses a generic orthonormal basis, such as Laguerre-Gaussian or Zernike functions, and the second one is a basis-free approach where the set of speckled patterns themselves form the basis. Using a set of simulated speckles patterns, we observed that the correct number of fibre modes can be obtained through the SVD decomposition, even at high levels of additive random noise. With a slight extension, using speckle patterns obtained at multiple excitation wavelengths (or equivalently, for different lengths of the same fiber) the method can also retrieve the shape of the actual fibre modes, by forming an appropriate linear combination of SVD modes.
Czech name
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Czech description
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Classification
Type
D - Article in proceedings
CEP classification
—
OECD FORD branch
10306 - Optics (including laser optics and quantum optics)
Result continuities
Project
<a href="/en/project/EF15_003%2F0000476" target="_blank" >EF15_003/0000476: Holographic endoscopy for in vivo applications</a><br>
Continuities
I - Institucionalni podpora na dlouhodoby koncepcni rozvoj vyzkumne organizace
Others
Publication year
2022
Confidentiality
S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů
Data specific for result type
Article name in the collection
Micro-Structured and Specialty Optical Fibres VII
ISBN
978-151065156-2
ISSN
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e-ISSN
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Number of pages
8
Pages from-to
(2022)
Publisher name
SPIE
Place of publication
Bellingham
Event location
online
Event date
May 9, 2022
Type of event by nationality
WRD - Celosvětová akce
UT code for WoS article
000838075300021