Measurement of spectra of fiber Bragg gratings by tuning the wavelength of a laser diode

We demonstrate the possibility of measuring reflection spectra of fiber Bragg gratings by tuning the wavelength of an off-the-shelf laser diode. Two methods of tuning are studied: temperature tuning at a frequency of 0.5 Hz and current tuning at a frequency of tens of kHz. A wavelength resolution of 2 pm is achieved for both methods. It is shown that by current tuning it is possible to interrogate fiber Bragg gratings at frequencies up to 100 kHz. Using the methods proposed, we have measured the shift of the reflection spectra of a fiber Bragg grating upon heating.

Automated summary

In this study, we demonstrate the feasibility of measuring reflection spectra of fiber Bragg gratings by tuning the wavelength of a commercially available laser diode. Two tuning methods, temperature and current tuning, are investigated. Both methods achieve a wavelength resolution of 2 pm, and it is shown that current tuning allows interrogation of fiber Bragg gratings at frequencies up to 100 kHz. Using the proposed methods, the shift of the reflection spectra of a fiber Bragg grating upon heating has been measured.