Spectral Optical Readout of Rectangular–Miniature Hollow Glass Tubing for Refractive Index Sensing
For answering the growing demand of innovative micro-fluidic devices able to measure the refractive index of samples in extremely low volumes, this paper presents an overview of the performances of a micro-opto-fluidic sensing platform that employs rectangular, miniature hollow glass tubings. The op...
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| Format: | Article |
| Language: | English |
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MDPI AG
2018-02-01
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| Series: | Sensors |
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| Online Access: | http://www.mdpi.com/1424-8220/18/2/603 |
| _version_ | 1798006771231490048 |
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| author | Giulia Rigamonti Valentina Bello Sabina Merlo |
| author_facet | Giulia Rigamonti Valentina Bello Sabina Merlo |
| author_sort | Giulia Rigamonti |
| collection | DOAJ |
| description | For answering the growing demand of innovative micro-fluidic devices able to measure the refractive index of samples in extremely low volumes, this paper presents an overview of the performances of a micro-opto-fluidic sensing platform that employs rectangular, miniature hollow glass tubings. The operating principle is described by showing the analytical model of the tubing, obtained as superposition of different optical cavities, and the optical readout method based on spectral reflectivity detection. We have analyzed, in particular, the theoretical and experimental optical features of rectangular tubings with asymmetrical geometry, thus with channel depth larger than the thickness of the glass walls, though all of them in the range of a few tens of micrometers. The origins of the complex line-shape of the spectral response in reflection, due to the different cavities formed by the tubing flat walls and channel, have been investigated using a Fourier transform analysis. The implemented instrumental configuration, based on standard telecom fiberoptic components and a semiconductor broadband optical source emitting in the near infrared wavelength region centered at 1.55 µm, has allowed acquisition of reflectivity spectra for experimental verification of the expected theoretical behavior. We have achieved detection of refractive index variations related to the change of concentration of glucose-water solutions flowing through the tubing by monitoring the spectral shift of the optical resonances. |
| first_indexed | 2024-04-11T13:00:54Z |
| format | Article |
| id | doaj.art-c966189a71fb4fd5afeec1e9ab75c608 |
| institution | Directory Open Access Journal |
| issn | 1424-8220 |
| language | English |
| last_indexed | 2024-04-11T13:00:54Z |
| publishDate | 2018-02-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Sensors |
| spelling | doaj.art-c966189a71fb4fd5afeec1e9ab75c6082022-12-22T04:22:57ZengMDPI AGSensors1424-82202018-02-0118260310.3390/s18020603s18020603Spectral Optical Readout of Rectangular–Miniature Hollow Glass Tubing for Refractive Index SensingGiulia Rigamonti0Valentina Bello1Sabina Merlo2Dipartimento di Ingegneria Industriale e dell’Informazione, Università di Pavia, 27100 Pavia, ItalyDipartimento di Ingegneria Industriale e dell’Informazione, Università di Pavia, 27100 Pavia, ItalyDipartimento di Ingegneria Industriale e dell’Informazione, Università di Pavia, 27100 Pavia, ItalyFor answering the growing demand of innovative micro-fluidic devices able to measure the refractive index of samples in extremely low volumes, this paper presents an overview of the performances of a micro-opto-fluidic sensing platform that employs rectangular, miniature hollow glass tubings. The operating principle is described by showing the analytical model of the tubing, obtained as superposition of different optical cavities, and the optical readout method based on spectral reflectivity detection. We have analyzed, in particular, the theoretical and experimental optical features of rectangular tubings with asymmetrical geometry, thus with channel depth larger than the thickness of the glass walls, though all of them in the range of a few tens of micrometers. The origins of the complex line-shape of the spectral response in reflection, due to the different cavities formed by the tubing flat walls and channel, have been investigated using a Fourier transform analysis. The implemented instrumental configuration, based on standard telecom fiberoptic components and a semiconductor broadband optical source emitting in the near infrared wavelength region centered at 1.55 µm, has allowed acquisition of reflectivity spectra for experimental verification of the expected theoretical behavior. We have achieved detection of refractive index variations related to the change of concentration of glucose-water solutions flowing through the tubing by monitoring the spectral shift of the optical resonances.http://www.mdpi.com/1424-8220/18/2/603rectangular glass tubingoptical resonatorrefractive index sensingoptical spectral measurementsresponse curves |
| spellingShingle | Giulia Rigamonti Valentina Bello Sabina Merlo Spectral Optical Readout of Rectangular–Miniature Hollow Glass Tubing for Refractive Index Sensing Sensors rectangular glass tubing optical resonator refractive index sensing optical spectral measurements response curves |
| title | Spectral Optical Readout of Rectangular–Miniature Hollow Glass Tubing for Refractive Index Sensing |
| title_full | Spectral Optical Readout of Rectangular–Miniature Hollow Glass Tubing for Refractive Index Sensing |
| title_fullStr | Spectral Optical Readout of Rectangular–Miniature Hollow Glass Tubing for Refractive Index Sensing |
| title_full_unstemmed | Spectral Optical Readout of Rectangular–Miniature Hollow Glass Tubing for Refractive Index Sensing |
| title_short | Spectral Optical Readout of Rectangular–Miniature Hollow Glass Tubing for Refractive Index Sensing |
| title_sort | spectral optical readout of rectangular miniature hollow glass tubing for refractive index sensing |
| topic | rectangular glass tubing optical resonator refractive index sensing optical spectral measurements response curves |
| url | http://www.mdpi.com/1424-8220/18/2/603 |
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