Now showing items 21-40 of 69

    • A fiber optic ammonia sensor using a universal pH indicator 

      Rodríguez Rodríguez, Adolfo Josué; Ruiz Zamarreño, Carlos Upna; Matías Maestro, Ignacio Upna; Arregui San Martín, Francisco Javier Upna; Cruz, René; May Arrioja, Daniel A. (MDPI, 2014)   Artículo / Artikulua  OpenAccess
      A universal pH indicator is used to fabricate a fiber optic ammonia sensor. The advantage of this pH indicator is that it exhibits sensitivity to ammonia over a broad wavelength range. This provides a differential response, ...
    • Fiber optic multiple-wavelength filter based on one dimensional photonic bandgap structures with defects 

      Del Villar, Ignacio Upna; Matías Maestro, Ignacio Upna; Arregui San Martín, Francisco Javier Upna (IEEE, 2004)   Artículo / Artikulua  OpenAccess
      In this paper, a theoretical analysis is given of an optical fiber multiple-wavelength tunable filter based on a onedimensional (1-D) photonic bandgap (PBG) structure with four defects. To understand the positioning of ...
    • Fiber-optic lossy mode resonance sensors 

      Arregui San Martín, Francisco Javier Upna; Del Villar, Ignacio Upna; Corres Sanz, Jesús María Upna; Goicoechea Fernández, Javier Upna; Ruiz Zamarreño, Carlos Upna; Elosúa Aguado, César Upna; Hernáez Sáenz de Zaitigui, Miguel Upna; Rivero Fuente, Pedro José Upna; Socorro Leránoz, Abián Bentor Upna; Urrutia Azcona, Aitor Upna; Sánchez Zábal, Pedro Upna; Zubiate Orzanco, Pablo Upna; López Torres, Diego Upna; Acha Morrás, Nerea de Upna; Matías Maestro, Ignacio Upna (Elsevier, 2014)   Contribución a Congreso / Biltzarrerako ekarpena  OpenAccess
      In the last 4 years, experimental evidences about the potential use of optical sensors based on Lossy Mode Resonances (LMR) have been presented in the literature. These LMR sensors have some similarities with Surface ...
    • Fiber-optic nanorefractometer based on one-dimensional photonic-bandgap structures with two defects 

      Del Villar, Ignacio Upna; Matías Maestro, Ignacio Upna; Arregui San Martín, Francisco Javier Upna (IEEE, 2004)   Artículo / Artikulua  OpenAccess
      A theoretical analysis of a fiber-optic photonic- bandgap (PBG)-based nanorefractometer is presented. Changes up to 11.2 dB in the optical output power in an index of refraction range of 1.7 with a sensitivity of 1.5 ...
    • Fringe generation with non-uniformly coated long-period fiber gratings 

      Del Villar, Ignacio Upna; Arregui San Martín, Francisco Javier Upna; Matías Maestro, Ignacio Upna; Cusano, Andrea; Paladino, Domenico; Cutolo, Antonello (Optical Society of America, 2007)   Artículo / Artikulua  OpenAccess
      In this work, the spectral characteristics of non-uniform symmetrically ring shaped coatings deposited on long-period fiber gratings (LPFGs) have been theoretically and experimentally investigated. To optimize the ...
    • Gasohol quality control for real time applications by means of a multimode interference fiber sensor 

      Rodríguez Rodríguez, Adolfo Josué; Baldovino Pantaleón, Óscar; Cruz, René; Ruiz Zamarreño, Carlos Upna; Matías Maestro, Ignacio Upna; May Arrioja, Daniel A. (MDPI, 2014)   Artículo / Artikulua  OpenAccess
      In this work we demonstrate efficient quality control of a variety of gasoline and ethanol (gasohol) blends using a multimode interference (MMI) fiber sensor. The operational principle relies on the fact that the addition ...
    • Generation of lossy mode resonances by deposition of high-refractive-index coatings on uncladded multimode optical fibers 

      Del Villar, Ignacio Upna; Ruiz Zamarreño, Carlos Upna; Sánchez Zábal, Pedro Upna; Hernáez Sáenz de Zaitigui, Miguel Upna; Fernández Valdivielso, Carlos Upna; Arregui San Martín, Francisco Javier Upna; Matías Maestro, Ignacio Upna (IOP Publishing Ltd, 2010)   Artículo / Artikulua  OpenAccess
      A comparative study of lossy mode resonances generated by depositing two different materials is presented. The two materials selected are indium tin oxide (ITO) and indium oxide. The two materials present different ...
    • Generation of lossy mode resonances with absorbing thin-films 

      Del Villar, Ignacio Upna; Ruiz Zamarreño, Carlos Upna; Hernáez Sáenz de Zaitigui, Miguel Upna; Arregui San Martín, Francisco Javier Upna; Matías Maestro, Ignacio Upna (IEEE, 2010)   Artículo / Artikulua  OpenAccess
      The generation of lossy mode resonances with absorbing thin-films is analyzed with electromagnetic theory. The main differences with surface plasmon resonances are presented and some rules are given towards an optimum ...
    • Generation of selective fringes with cascaded long-period gratings 

      Del Villar, Ignacio Upna; Achaerandio, Miguel Upna; Arregui San Martín, Francisco Javier Upna; Matías Maestro, Ignacio Upna (IEEE, 2006)   Artículo / Artikulua  OpenAccess
      The inscription of cascaded long-period gratings of different periods in optical fiber permits us to obtain both narrowband and wideband filters in the same spectrum. If used as an optical transducer, it may permit us ...
    • Generation of surface plasmon resonance and lossy mode resonance by thermal treatment of ITO thin-films 

      Del Villar, Ignacio Upna; Ruiz Zamarreño, Carlos Upna; Hernáez Sáenz de Zaitigui, Miguel Upna; Sanchez, Pedro; Arregui San Martín, Francisco Javier Upna; Matías Maestro, Ignacio Upna (Elsevier, 2014)   Artículo / Artikulua  OpenAccess
      Silicon wafers coated with IndiumTinOxide (ITO) by application of sputtering technique have been characterized after different post-annealing techniques, showing that this last factor is critical for the quality of the ...
    • Giant sensitivity of optical fiber sensors by means of lossy moderesonance 

      Arregui San Martín, Francisco Javier Upna; Del Villar, Ignacio Upna; Ruiz Zamarreño, Carlos Upna; Zubiate Orzanco, Pablo Upna; Matías Maestro, Ignacio Upna (Elsevier, 2016)   Artículo / Artikulua  OpenAccess
      Here we show an optical refractometer with a giant sensitivity of 304,360 nm per refractive index unit(nm/RIU). This sensitivity corresponds to a resolution of 3.28 × 10−9RIU if a standard optical spectrumanalyzer with a ...
    • High sensitive refractometers based on lossy mode resonances (LMRs) supported by ITO coated D-shaped optical fibers 

      Zubiate Orzanco, Pablo Upna; Ruiz Zamarreño, Carlos Upna; Del Villar, Ignacio Upna; Matías Maestro, Ignacio Upna; Arregui San Martín, Francisco Javier Upna (Optical Society of America, 2015)   Artículo / Artikulua  OpenAccess
      Tin doped indium oxide (ITO) coatings fabricated onto D-shaped optical fibers are presented as the supporting medium for Lossy Mode Resonances (LMRs) generation. The characteristic geometry of ITO-coated D-shaped optical ...
    • High sensitivity humidity sensor based on cladding-etched optical fiber and lossy mode resonances 

      Ascorbe Muruzabal, Joaquín Upna; Corres Sanz, Jesús María Upna; Matías Maestro, Ignacio Upna; Arregui San Martín, Francisco Javier Upna (Elsevier, 2016)   Artículo / Artikulua  OpenAccess
      In this work a high sensitivity optical fiber humidity sensor (OFHS) is presented. The configuration chosen for this purpose is a cladding-etched single mode optical fiber (CE-SMF) coated with a thin film of tin oxide ...
    • Humidity sensor based on Bragg gratings developed on the end facet of an optical fiber by sputtering of one single material 

      Ascorbe Muruzabal, Joaquín Upna; Corres Sanz, Jesús María Upna; Arregui San Martín, Francisco Javier Upna; Matías Maestro, Ignacio Upna (MDPI, 2017)   Artículo / Artikulua  OpenAccess
      The refractive index of sputtered indium oxide nanocoatings has been altered just by changing the sputtering parameters, such as pressure. These induced changes have been exploited for the generation of a grating on the ...
    • Increasing the sensitivity of an optic level sensor with a wavelength and phase sensitive single-mode multimode single-mode (SMS) fiber structure 

      Fuentes, Omar; Del Villar, Ignacio Upna; Vento, José R.; Socorro Leránoz, Abián Bentor Upna; Gallego, E.E.; Corres Sanz, Jesús María Upna; Matías Maestro, Ignacio Upna (IEEE, 2017)   Artículo / Artikulua  OpenAccess
      The sensitivity of a liquid level sensor based on a single-mode-multimode-single-mode fiber structure has been increased by hydrofluoric acid etching. The etching process was analyzed and monitored both theoretical and ...
    • Influence in cladding mode distribution of overlay deposition on long-period fiber gratings 

      Del Villar, Ignacio Upna; Matías Maestro, Ignacio Upna; Arregui San Martín, Francisco Javier Upna (Optical Society of America, 2006)   Artículo / Artikulua  OpenAccess
      A thin overlay of higher refractive index than that of the cladding of a long-period fiber grating induces in cladding modes strong variations in effective index, mode profile, cross-coupling coefficient with the core ...
    • Integración de tecnologías inalámbricas en sistemas de control y monitorización 

      Nazábal Urriza, Juan Antonio Upna (2014)   Tesis doctoral / Doktoretza tesia  OpenAccess
      En este trabajo se explora el concepto de ‘Internet of things’ y la integración de diferentes tecnologías de sensado en un mismo sistema de monitorización y control remoto. Básicamente la idea consiste en que todo esté ...
    • Long period fiber gratings with overlay of variable refractive index 

      Del Villar, Ignacio Upna; Matías Maestro, Ignacio Upna; Arregui San Martín, Francisco Javier Upna (IEEE, 2005)   Artículo / Artikulua  OpenAccess
      A theoretical analysis is presented of a long-period fiber grating (LPFG) with an overlay of variable refractive index. The highest sensitivity of the resonance wavelengths to variations in the refractive index of the ...
    • Lossy mode resonance generation with indium tin oxide coated optical fibers for sensing applications 

      Del Villar, Ignacio Upna; Ruiz Zamarreño, Carlos Upna; Hernáez Sáenz de Zaitigui, Miguel Upna; Arregui San Martín, Francisco Javier Upna; Matías Maestro, Ignacio Upna (IEEE, 2010)   Artículo / Artikulua  OpenAccess
      Surface plasmon resonances and lossy mode resonances can be generated with Indium Tin Oxide (ITO) coated optical fibers. Both phenomena are analyzed and compared. Lossy mode resonances present important advantages: ...
    • Luminescence-based optical sensors fabricated by means of the layer-by-layer nano-assembly technique 

      Acha Morrás, Nerea de Upna; Elosúa Aguado, César Upna; Matías Maestro, Ignacio Upna; Arregui San Martín, Francisco Javier Upna (MDPI, 2017)   Artículo / Artikulua  OpenAccess
      Luminescence-based sensing applications range from agriculture to biology, including medicine and environmental care, which indicates the importance of this technique as a detection tool. Luminescent optical sensors are ...