Abstract
Online measurement of diameters and concentricities of optical fibre layers, and the coating layer in particular, is one of the challenges in fibre manufacturing. Currently available instruments can measure concentricity and diameter of layers offline, and are not suitable for precise monitoring or control of the manufacturing process in real time. In this work, we use two laser beams, positioned orthogonally to illuminate the fibre from two sides, and calculate deviations from the expected geometry by analysing the scattering pattern. To measure the diffraction pattern we use two 8K linear array detectors, with the scattered light incident directly on the sensors. Each detector is capturing approximately 90° angular range directly behind the fibre. The two measurement channels are positioned at different heights. The scattered pattern is modelled mathematically with finite-element and Fourier-modal methods, with various diameter and concentricity deviations. The sensitivities of the changes in the scattering pattern are identified in respect to these deviations. Since calculations are computationally intensive, the sensitivities are pre-calculated in advance, and the realtime measurement is based on pattern recognition. The symmetry of the pattern is used to differentiate between diameter and concentricity variations. We performed online measurements with the prototype instrument in production conditions, and show that this method is sensitive enough to measure deviations of under 1 μm in diameter and concentricity of the coating layer.
| Original language | English |
|---|---|
| Title of host publication | Fiber Lasers and Glass Photonics |
| Subtitle of host publication | Materials through Applications |
| Editors | Stefano Taccheo, Jacob I. Mackenzie, Maurizio Ferrari |
| Publisher | International Society for Optics and Photonics SPIE |
| ISBN (Electronic) | 978-1-5106-1892-3 |
| DOIs | |
| Publication status | Published - 2018 |
| MoE publication type | A4 Article in a conference publication |
| Event | Fiber Lasers and Glass Photonics : Materials through Applications 2018 - Strasbourg, France Duration: 22 Apr 2018 → 26 Apr 2018 |
Conference
| Conference | Fiber Lasers and Glass Photonics |
|---|---|
| Country | France |
| City | Strasbourg |
| Period | 22/04/18 → 26/04/18 |
Fingerprint
Keywords
- Concentricity
- Fibre
- Manufacturing
- Modelling
- Scatterometry
Cite this
}
Online measurement of optical fibre geometry during manufacturing. / Shpak, Maksim; Burger, Sven; Byman, Ville; Saastamoinen, Kimmo; Haapalainen, Mertsi; Lassila, Antti.
Fiber Lasers and Glass Photonics: Materials through Applications. ed. / Stefano Taccheo; Jacob I. Mackenzie; Maurizio Ferrari. International Society for Optics and Photonics SPIE, 2018. 1068318 (Proceedings of SPIE, Vol. 10683).Research output: Chapter in Book/Report/Conference proceeding › Conference article in proceedings › Scientific › peer-review
TY - GEN
T1 - Online measurement of optical fibre geometry during manufacturing
AU - Shpak, Maksim
AU - Burger, Sven
AU - Byman, Ville
AU - Saastamoinen, Kimmo
AU - Haapalainen, Mertsi
AU - Lassila, Antti
PY - 2018
Y1 - 2018
N2 - Online measurement of diameters and concentricities of optical fibre layers, and the coating layer in particular, is one of the challenges in fibre manufacturing. Currently available instruments can measure concentricity and diameter of layers offline, and are not suitable for precise monitoring or control of the manufacturing process in real time. In this work, we use two laser beams, positioned orthogonally to illuminate the fibre from two sides, and calculate deviations from the expected geometry by analysing the scattering pattern. To measure the diffraction pattern we use two 8K linear array detectors, with the scattered light incident directly on the sensors. Each detector is capturing approximately 90° angular range directly behind the fibre. The two measurement channels are positioned at different heights. The scattered pattern is modelled mathematically with finite-element and Fourier-modal methods, with various diameter and concentricity deviations. The sensitivities of the changes in the scattering pattern are identified in respect to these deviations. Since calculations are computationally intensive, the sensitivities are pre-calculated in advance, and the realtime measurement is based on pattern recognition. The symmetry of the pattern is used to differentiate between diameter and concentricity variations. We performed online measurements with the prototype instrument in production conditions, and show that this method is sensitive enough to measure deviations of under 1 μm in diameter and concentricity of the coating layer.
AB - Online measurement of diameters and concentricities of optical fibre layers, and the coating layer in particular, is one of the challenges in fibre manufacturing. Currently available instruments can measure concentricity and diameter of layers offline, and are not suitable for precise monitoring or control of the manufacturing process in real time. In this work, we use two laser beams, positioned orthogonally to illuminate the fibre from two sides, and calculate deviations from the expected geometry by analysing the scattering pattern. To measure the diffraction pattern we use two 8K linear array detectors, with the scattered light incident directly on the sensors. Each detector is capturing approximately 90° angular range directly behind the fibre. The two measurement channels are positioned at different heights. The scattered pattern is modelled mathematically with finite-element and Fourier-modal methods, with various diameter and concentricity deviations. The sensitivities of the changes in the scattering pattern are identified in respect to these deviations. Since calculations are computationally intensive, the sensitivities are pre-calculated in advance, and the realtime measurement is based on pattern recognition. The symmetry of the pattern is used to differentiate between diameter and concentricity variations. We performed online measurements with the prototype instrument in production conditions, and show that this method is sensitive enough to measure deviations of under 1 μm in diameter and concentricity of the coating layer.
KW - Concentricity
KW - Fibre
KW - Manufacturing
KW - Modelling
KW - Scatterometry
UR - http://www.scopus.com/inward/record.url?scp=85049774220&partnerID=8YFLogxK
U2 - 10.1117/12.2314762
DO - 10.1117/12.2314762
M3 - Conference article in proceedings
BT - Fiber Lasers and Glass Photonics
A2 - Taccheo, Stefano
A2 - Mackenzie, Jacob I.
A2 - Ferrari, Maurizio
PB - International Society for Optics and Photonics SPIE
ER -