Fiber Bragg grating based linear cavity fibre laser temperature sensor with enhanced optical signal-to-noise ratio

Abstract

An optical temperature sensor based on linear cavity erbium-doped fiber laser is proposed in this work. A fiber Bragg grating is utilized in the laser cavity as the sensor head for temperature detection. Experimental results suggest that the laser wavelength has linear relationship with temperature. As the temperature increases from 25 °C to 55 °C, the laser wavelength shifts linearly from 1550.168 nm to 1550.524 nm with the recorded sensitivity of 11.7 pm °C−1 . The laser is also found to be stable with fluctuation of less than 0.42 dB and it has 3 dB linewidth of 0.024 nm. Moreover, the laser has high optical signal-to-noise ratio (OSNR) of 55 dB and this arises from the use of linear cavity in this design. Resulting from the signal amplification that happens twice in the linear cavity for a round trip, the laser gets high power and this enhances the laser OSNR. The high OSNR of the laser is beneficial to improve the sensor detection limit.

Compact silica-based equal nine-channel generated by triple-layer arrays

“…The diffraction theory or experimental fabrication of traditional gratings have been extensively studied [1][2][3][4]. By optimizing the grating profile parameters, the designed grating can be used in various fields, such as sensors [5], beam splitters [6][7][8], polarizers [9][10][11], filters [12][13][14], absorbers [15][16][17][18], and solar cells [19][20][21][22], etc.…”

Pencil-like periodic ridges under second Bragg incidence as dual-function beam separation

“…Nowadays, periodic diffraction has played an important role in many fields of engineering, especially in optoelectronic systems. For instance, it can be used in laser systems [1][2][3][4], optical communication systems [5][6][7], optical detection [8][9][10][11], and so on. Different parameters of the grating and incident conditions can cause different performance of the grating.…”

Dual-Polarization Distributed Feedback Fiber Laser Sensor Based on Femtosecond Laser-Inscribed In-Fiber Stressors for Simultaneous Strain and Temperature Measurements

“…However, the passive FBGs typically have a broad bandwidth of around several hundreds of picometers in the reflection spectra. The relatively large bandwidth could lead to low resolution in FBG sensors [10]. Moreover, the optical signals reflected from FBG sensors are always weak, especially when the FBGs are located at a long distance away from the interrogator.…”