A fast tunable semiconductor laser for FBG sensor interrogation systems

Abstract

We demonstrate a fast Quasi-Continuous frequency scanning semiconductor laser source for optical fiber sensor interrogation systems. The tunable laser covers a wavelength range of 32nm in C-band with tuning resolution of 8pm. The scanning time over the complete wavelength range in C band is less than 1ms while the switching time from one wavelength point to another point can be less than 100ns. A fast current driver controlled using FPGAs have been employed to drive a DSDBR laser for the realization of the fast tunable laser module. Experimental results have verified its possible application in optical sensor interrogation systems.

Narrow-linewidth self-sweeping fiber laser with scanning range control by a tunable Lyot filter

“…Tunable lasers have many practical applications, such as WDM communication systems [1], spectroscopy [2], sensor interrogation [3] and so on. There are many ways for wavelength tuning in a laser system.…”

A novel algorithm based on DFB tunable laser array for demodulation of FBG sensors

“…In previous works, many demodulation algorithms have been proposed, such as cross-correlation method [4], peak searching method [5,6,7], and modified centroid algorithm [8].…”

“…Then the strain is demodulated by a cross-correlation algorithm. For peak searching method [5,6,7], output wavelength of tunable laser need to be tuned by injection current/temperature to search and match the reflected FBG's center wavelength. In [8], rapid wavelength tuning of laser has to be made through FBG's whole spectrum and modified centroid algorithm is utilized for the demodulation of nonequidistantly sampled FBG sensor signals.…”