Open Access
Láser random de fibra óptica asistido por reflectores de fibra con retrodispersión controlada artificialmente
(SEDOPTICA, 2021) Pérez Herrera, Rosa Ana; Roldán Varona, Pablo; Galarza Galarza, Marko; Sañudo-Lasagabaster Ibáñez, Silvia; Rodríguez Cobo, Luis; López Higuera, José Miguel; López-Amo Sáinz, Manuel; Ingeniaritza Elektrikoa, Elektronikoaren eta Telekomunikazio Ingeniaritzaren; Institute of Smart Cities - ISC; Ingeniería Eléctrica, Electrónica y de Comunicación; Universidad Pública de Navarra / Nafarroako Unibertsitate Publikoa, PJUPNA1928
Este trabajo presenta un láser de fibra tipo random (LFR) en cavidad semi-abierta, mediante amplificación híbrida Raman-Erbio y asistida por reflectores de fibra con retrodispersión controlada artificialmente (RFRCA). Como medio activo se ha empleado una combinación de 2,4 km de fibra compensadora de dispersión con dos tramos de fibra altamente dopada con erbio de 5 m cada uno. Se ha obtenido una única línea de emisión láser centrada a en 1553.8 nm y con una relación señal a ruido óptica de 47 dB cuando en la estructura se inyectaba una potencia de bombeo de 37.5 dBm. Además, se ha medido la estabilidad en términos de potencia de salida de este láser durante 3 horas, obteniendo una inestabilidad tan baja como 0,08 dB con un nivel de confianza del 100%.
Open Access
Labescape and breakout: gamification for photonics students
(IATED, 2021) Pérez Herrera, Rosa Ana; Tainta Ausejo, Santiago; Elosúa Aguado, César; Ingeniaritza Elektrikoa, Elektronikoaren eta Telekomunikazio Ingeniaritzaren; Institute of Smart Cities - ISC; Ingeniería Eléctrica, Electrónica y de Comunicación; Universidad Pública de Navarra / Nafarroako Unibertsitate Publikoa
Nowadays, the idea of using game mechanisms in non-gaming environments has become of great interest in different fields such as education or training. Not only for primary school but also in higher formal education, game-based learning appears to be an emerging trend in wide-ranging knowledge areas such as health, social policy, or engineering, among others. By employing this methodology, the process of learning becomes more motivating while reaching, in some cases, a competitive level. Game-based learning has been widely adopted in many engineering learning areas, such as for example electronics thanks to the ready availability of low-cost electronic equipment. The authors' extensive teaching experience in subjects related to electronics and photonics has led us to consider its implementation in more ambitious teaching fields. For instance, and despite the broad acceptance, its use in the field of photonics is still very scarce. The high cost of required equipment has hindered the expansion of these strategies, taking its implementation longer than desired and being too expensive at times. In the present work, the authors propose a planning and design scheme for a new gamification strategy based on an escape-room in which, all the tests to be passed will be related to the field of optics and photonics using low-cost equipment. The main field of application of this novel teaching strategy will be in the practical section of the subjects that is usually carried out in a laboratory and will be aimed at both undergraduate and master's degree students. The resolution of tests in different game sequences of the escape room is proposed, that is, linear, open, or multi-linear paths, adapting the degree of difficulty of the tests to the level of the group of students. Additionally, a co-evaluation method is suggested where the rest of the students will provide a valuable feedback to each one of their colleagues.
Open Access
Multiplexing optical fiber Fabry-Perot interferometers based on air-microcavities
(SPIE, 2019) Pérez Herrera, Rosa Ana; Novais, Susana; Bravo Acha, Mikel; Leandro González, Daniel; Silva, Susana; Frazão, Orlando; López-Amo Sáinz, Manuel; Ingeniaritza Elektrikoa, Elektronikoaren eta Telekomunikazio Ingeniaritzaren; Institute of Smart Cities - ISC; Ingeniería Eléctrica, Electrónica y de Comunicación
In this work we demonstrate the multiplexing capability of new optical fiber Fabry-Perot interferometers based on airmicrocavities using a commercial FBG interrogator. Three optimized air-microcavity interferometer sensors have been multiplexed in a single network and have been monitored using the commercial FBGs interrogator in combination with FFT calculations. Results show a sensitivity of 2.18 π rad/mε and a crosstalk-free operation.
Open Access
Micro-displacement sensor based on hollow core fiber interferometers
(Optica, 2022) Sánchez González, Arturo; Rodríguez Rodríguez, Armando; Dauliat, Romain; Jamier, Raphael; Roy, Philippe; Pérez Herrera, Rosa Ana; López-Amo Sáinz, Manuel; Ingeniería Eléctrica, Electrónica y de Comunicación; Institute of Smart Cities - ISC; Ingeniaritza Elektrikoa, Elektronikoaren eta Telekomunikazio Ingeniaritzaren
An interferometric sensor based on hollow core fibers for the measurement of micro-displacement has been designed. Its characterization has resulted in a linear response, suggesting its application in pressure sensors.
Open Access
Erbium-doped fiber ring cavity for the measurement of refractive index variations
(SPIE, 2023) Pérez Herrera, Rosa Ana; Soares, Liliana; Novais, Susana; Frazão, Orlando; Silva, Susana; Ingeniería Eléctrica, Electrónica y de Comunicación; Institute of Smart Cities - ISC; Ingeniaritza Elektrikoa, Elektronikoaren eta Telekomunikazio Ingeniaritzaren
In this work, an erbium-doped fiber ring cavity based on a 3dB optical coupler for refractive index measurements is presented and experimentally verified. This interrogation system, based on a 1 x 2 optical coupler, uses one of these output ports to increase the reflected optical power by means of a fiber Bragg Grating (FBG), used as a reflector. Moreover, the other output port is used as a refractive index sensing head. A spectral analysis of this interrogator system as well as a fiber cavity ring refractive index sensor characterization are carried out. Finally, an experimental comparison of the refractive index sensor range when the 3dB coupler is replace by a 1x3 one is also presented.
Open Access
Modulated fiber ring laser and its application in high-sensitivity temperature sensors
(SPIE, 2016) Pérez Herrera, Rosa Ana; Tainta Ausejo, Santiago; Erro Betrán, María José; López-Amo Sáinz, Manuel; Ingeniaritza Elektrikoa eta Elektronikoa; Institute of Smart Cities - ISC; Ingeniería Eléctrica y Electrónica
This work presents an experimental demonstration of a scheme based on an internally modulated fiber ring laser for high-sensitivity temperature sensing. The attained temperature resolution has been as low as ± 2pm even when a commercial FBG with a sensitivity of 10 pm/°C was used. Thus, a fivefold improvement in the temperature sensor resolution can be achieved when compared to a simple FBG interrogation scheme. In addition to this, the measuring range could be selected only by changing the frequency modulation of the fiber ring laser. This technology also allows to triple the photodiode bandwidth unambiguously when temperature or strain measurements are carried out, which is a remarkable achievement in term of cost reduction.
Open Access
Random fiber lasers: application to fiber optic sensors networks
(IEEE, 2017) López-Amo Sáinz, Manuel; Leandro González, Daniel; Miguel Soto, Verónica de; Bravo Acha, Mikel; Fernández Vallejo, Montserrat; Pérez Herrera, Rosa Ana; Ingeniaritza Elektrikoa eta Elektronikoa; Institute of Smart Cities - ISC; Ingeniería Eléctrica y Electrónica
Recently, random mirrors have been proposed as a method to create fiber laser cavities. This kind of cavity is based on cooperative Rayleigh scattering, which is generated along a fiber due to the material inhomogeneities presented in that fiber. In this work, basics of Random fiber lasers and different demonstrated lasing sensors systems for interrogating arrays of optical fiber sensors are shown. These systems use different kinds of amplification and cavities schemes and can interrogate optical fiber sensors located up to 225 km away.
Open Access
WDM and TDM interrogation by sequentially pulsing direct modulated DFBs
(Optica, 2020) Pérez González, Asier; Bravo Acha, Mikel; Leandro González, Daniel; Pérez Herrera, Rosa Ana; López-Amo Sáinz, Manuel; Ingeniería Eléctrica, Electrónica y de Comunicación; Ingeniaritza Elektrikoa, Elektronikoaren eta Telekomunikazio Ingeniaritzaren; Institute of Smart Cities - ISC
A new versatile and cost-effective interrogation system by pulsing direct modulated (DM) DFB laser diodes is proposed. 1 pm wavelength resolution and 600 m sensor spacing is demonstrated by sequentially pulsing a DM DFB.
Open Access
Short pulse generation in erbium-doped fiber lasers using graphene oxide as a saturable absorber
(Science and Technology Publications, Lda., 2023) Monteiro, Catarina S.; Pérez Herrera, Rosa Ana; Silva, Susana; Frazão, Orlando; Ingeniería Eléctrica, Electrónica y de Comunicación; Ingeniaritza Elektrikoa, Elektronikoa eta Telekomunikazio Ingeniaritza; Institute of Smart Cities - ISC
The use of graphene oxide (GO) as a saturable absorber for short pulses generation in an Erbium-doped fiber laser was studied and demonstrated. The saturable absorber consisted of a thin GO film, with a high concentration of monolayer GO flakes, spray-coated on the end face of a ferrule-connected fiber. By including the saturable absorber in the laser cavity and controlling the intra-cavity polarization, the generation of short-pulsed light was achieved under mode-locking and Q-switching operations. Under mode-locking operation, it was observed a pulse train with a fundamental repetition rate of 1.48 MHz, with a working wavelength centered at 1564.4 nm. In the Q-switch operation, a pulse train with a 12.7 kHz repetition rate and a 14.3 µs pulse duration was attained for a 230-mA pump current. Further investigation showed a linear dependence of the repetition rate with the pump power, attaining frequencies between 12.7 and 14.4 kHz.
Open Access
High sensitive micro-displacement intensity fiber sensor by using a multiwavelength erbium doped fiber ring laser based on optical add-drop multiplexers
(SPIE, 2014-06-02) Pérez Herrera, Rosa Ana; Leandro González, Daniel; López-Amo Sáinz, Manuel; Ingeniería Eléctrica y Electrónica; Ingeniaritza Elektrikoa eta Elektronikoa
In this work, a wavelength division multiplexed fiber ring laser, based on optical add-drop multiplexers to interconnect intensity sensors has been experimentally demonstrated. Three different laser lines were obtained simultaneously all with an optical signal to noise ratio higher than 30dB. This proposed configuration is based on commercial devices and is adapted to the ITU channels normative. By using this configuration each sensor was associated with a different wavelength directly offered by each OADM and a reference wavelength was also included in order to distinguish between power variations induced by the transducer or to detect a fiber failure. This sensor system has been experimentally verified by using microbending sensors obtaining experimental slope sensitivity as good as -0.327dB/µm.