Mapping the Salinity Gradient in a Microfluidic Device with Schlieren Imaging
This work presents the use of the schlieren imaging to quantify the salinity gradients in a microfluidic device. By partially blocking the back focal plane of the objective lens, the schlieren microscope produces an image with patterns that correspond to spatial derivative of refractive index in the...
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| Format: | Article |
| Language: | English |
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MDPI AG
2015-05-01
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| Series: | Sensors |
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| Online Access: | http://www.mdpi.com/1424-8220/15/5/11587 |
| _version_ | 1811300740302372864 |
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| author | Chen-li Sun Shao-Tuan Chen Po-Jen Hsiao |
| author_facet | Chen-li Sun Shao-Tuan Chen Po-Jen Hsiao |
| author_sort | Chen-li Sun |
| collection | DOAJ |
| description | This work presents the use of the schlieren imaging to quantify the salinity gradients in a microfluidic device. By partially blocking the back focal plane of the objective lens, the schlieren microscope produces an image with patterns that correspond to spatial derivative of refractive index in the specimen. Since salinity variation leads to change in refractive index, the fluid mixing of an aqueous salt solution of a known concentration and water in a T-microchannel is used to establish the relation between salinity gradients and grayscale readouts. This relation is then employed to map the salinity gradients in the target microfluidic device from the grayscale readouts of the corresponding micro-schlieren image. For saline solution with salinity close to that of the seawater, the grayscale readouts vary linearly with the salinity gradient, and the regression line is independent of the flow condition and the salinity of the injected solution. It is shown that the schlieren technique is well suited to quantify the salinity gradients in microfluidic devices, for it provides a spatially resolved, non-invasive, full-field measurement. |
| first_indexed | 2024-04-13T06:56:51Z |
| format | Article |
| id | doaj.art-4730cb311d8f4229a29bfab9910a330b |
| institution | Directory Open Access Journal |
| issn | 1424-8220 |
| language | English |
| last_indexed | 2024-04-13T06:56:51Z |
| publishDate | 2015-05-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Sensors |
| spelling | doaj.art-4730cb311d8f4229a29bfab9910a330b2022-12-22T02:57:14ZengMDPI AGSensors1424-82202015-05-01155115871160010.3390/s150511587s150511587Mapping the Salinity Gradient in a Microfluidic Device with Schlieren ImagingChen-li Sun0Shao-Tuan Chen1Po-Jen Hsiao2Department of Mechanical Engineering, National Taiwan University, 1 Roosevelt Road Section 4, Taipei 10617, TaiwanDepartment of Mechanical Engineering, National Taiwan University, 1 Roosevelt Road Section 4, Taipei 10617, TaiwanDepartment of Mechanical Engineering, National Taiwan University, 1 Roosevelt Road Section 4, Taipei 10617, TaiwanThis work presents the use of the schlieren imaging to quantify the salinity gradients in a microfluidic device. By partially blocking the back focal plane of the objective lens, the schlieren microscope produces an image with patterns that correspond to spatial derivative of refractive index in the specimen. Since salinity variation leads to change in refractive index, the fluid mixing of an aqueous salt solution of a known concentration and water in a T-microchannel is used to establish the relation between salinity gradients and grayscale readouts. This relation is then employed to map the salinity gradients in the target microfluidic device from the grayscale readouts of the corresponding micro-schlieren image. For saline solution with salinity close to that of the seawater, the grayscale readouts vary linearly with the salinity gradient, and the regression line is independent of the flow condition and the salinity of the injected solution. It is shown that the schlieren technique is well suited to quantify the salinity gradients in microfluidic devices, for it provides a spatially resolved, non-invasive, full-field measurement.http://www.mdpi.com/1424-8220/15/5/11587salinity gradientmicroscale schlieren techniquemicrofluidicquantitative analysis |
| spellingShingle | Chen-li Sun Shao-Tuan Chen Po-Jen Hsiao Mapping the Salinity Gradient in a Microfluidic Device with Schlieren Imaging Sensors salinity gradient microscale schlieren technique microfluidic quantitative analysis |
| title | Mapping the Salinity Gradient in a Microfluidic Device with Schlieren Imaging |
| title_full | Mapping the Salinity Gradient in a Microfluidic Device with Schlieren Imaging |
| title_fullStr | Mapping the Salinity Gradient in a Microfluidic Device with Schlieren Imaging |
| title_full_unstemmed | Mapping the Salinity Gradient in a Microfluidic Device with Schlieren Imaging |
| title_short | Mapping the Salinity Gradient in a Microfluidic Device with Schlieren Imaging |
| title_sort | mapping the salinity gradient in a microfluidic device with schlieren imaging |
| topic | salinity gradient microscale schlieren technique microfluidic quantitative analysis |
| url | http://www.mdpi.com/1424-8220/15/5/11587 |
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