Search

Your search keyword '"Koken Fukushima"' showing total 2 results
Start Over Author "Koken Fukushima" Language english
2 results on '"Koken Fukushima"'

1. Loss-Modulation-Based Wavelength-Range Shifting of Tunable EDF Ring Laser with Cascaded-Chirped Long-Period Fiber Grating for Temperature Measurement

Author

Koken Fukushima, Manuel Guterres Soares, Atsushi Wada, Satoshi Tanaka, and Fumihiko Ito

Subjects
tunable lasers, optical fiber sensors, long-period fiber gratings (LPG), cascaded-chirped long-period fiber gratings (C-CLPG), Erbium-doped fiber ring lasers (EDFRL), variable optical attenuator (VOA), Chemical technology, TP1-1185
Abstract

A novel tunable Erbium-doped fiber ring laser (EDFRL) with a cascaded-chirped long-period fiber grating (C-CLPG) as a wavelength selection filter is proposed from the viewpoint of the sensor use, in which a variable optical attenuator (VOA) is employed as an intracavity loss modulator to change the oscillation wavelength region so that the resultant tuning wavelength range is widened. In the demonstrative experiment for temperature measurements, oscillation over the wavelength range of 12.85 nm (1557.62~1570.47 nm), which is more than three times range of the previously presented laser and is equivalent to 64 °C in terms of temperature change, was achieved, while a single-wavelength oscillation was maintained. In addition, a practical technique for realizing a temperature measurement by combining with the VOA control is also discussed.

Published
2021
Full Text
View/download PDF

2. EDF ring laser using cascaded-chirped long period fiber grating for temperature measurement

Author

Fumihiko Ito, Koken Fukushima, Satoshi Tanaka, Manuel Guterres Soares, Atsushi Wada, Koki Nakaya, and Quoc Hung Bui

Subjects
Materials science, Oscillation, business.industry, Physics::Optics, Ring laser, 02 engineering and technology, Long-period fiber grating, 021001 nanoscience & nanotechnology, 01 natural sciences, Temperature measurement, Atomic and Molecular Physics, and Optics, 010309 optics, Wavelength, Optics, Fiber optic sensor, Fiber laser, 0103 physical sciences, Transmittance, 0210 nano-technology, business
Abstract

A novel tunable erbium-doped fiber ring laser (EDFRL) using a cascaded-chirped long period fiber grating (C-CLPG) as a wavelength selection element is proposed. The oscillation wavelength is determined by the one of the spectral peaks of the C-CLPG used, and the oscillation output provides a high signal to noise (S/N) ratio detection and a highly sensitive measurement of the temperature due to its high power and narrow spectral output. In the experiment, it is confirmed that the wavelength of the output shifts in accordance with the temperature-induced spectral shift of the C-CLPG transmittance spectrum and the temperature sensitivity is obtained to be ∼-0.2 nm/°C within the wavelength range of 1567.30 ∼ 1575.78 nm. The oscillation wavelength range is to be limited depending on the fringe spacing of the channeled spectrum of C-CLPG, which limits the temperature measurement range, but a data processing approach to solve this problem is additionally proposed and its availability is also presented.

Published
2020

Catalog

Books, media, physical & digital resources
See catalog results