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Multilayer thin-film phantoms for axial contrast transfer function measurement in optical coherence tomography
In optical coherence tomography (OCT), axial resolution is one of the most critical parameters impacting image quality. It is commonly measured by determining the point spread function (PSF) based on a specular surface reflection. The contrast transfer function (CTF) provides more insights into an i...
Autores principales: | , , , , |
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Formato: | Online Artículo Texto |
Lenguaje: | English |
Publicado: |
Optical Society of America
2013
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Materias: | |
Acceso en línea: | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3704096/ https://www.ncbi.nlm.nih.gov/pubmed/23847740 http://dx.doi.org/10.1364/BOE.4.001166 |
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author | Agrawal, Anant Chen, Chao-Wei Baxi, Jigesh Chen, Yu Pfefer, T. Joshua |
author_facet | Agrawal, Anant Chen, Chao-Wei Baxi, Jigesh Chen, Yu Pfefer, T. Joshua |
author_sort | Agrawal, Anant |
collection | PubMed |
description | In optical coherence tomography (OCT), axial resolution is one of the most critical parameters impacting image quality. It is commonly measured by determining the point spread function (PSF) based on a specular surface reflection. The contrast transfer function (CTF) provides more insights into an imaging system’s resolving characteristics and can be readily generated in a system-independent manner, without consideration for image pixel size. In this study, we developed a test method for determination of CTF based on multi-layer, thin-film phantoms, evaluated using spectral- and time-domain OCT platforms with different axial resolution values. Phantoms representing six spatial frequencies were fabricated and imaged. The fabrication process involved spin coating silicone films with precise thicknesses in the 8-40 μm range. Alternating layers were doped with a specified concentration of scattering particles. Validation of layer optical properties and thicknesses were achieved with spectrophotometry and stylus profilometry, respectively. OCT B-scans were used to calculate CTFs and results were compared with convetional PSF measurements based on specular reflections. Testing of these phantoms indicated that our approach can provide direct access to axial resolution characteristics highly relevant to image quality. Furthermore, tissue phantoms based on our thin-film fabrication approach may have a wide range of additional applications in optical imaging and spectroscopy. |
format | Online Article Text |
id | pubmed-3704096 |
institution | National Center for Biotechnology Information |
language | English |
publishDate | 2013 |
publisher | Optical Society of America |
record_format | MEDLINE/PubMed |
spelling | pubmed-37040962013-07-11 Multilayer thin-film phantoms for axial contrast transfer function measurement in optical coherence tomography Agrawal, Anant Chen, Chao-Wei Baxi, Jigesh Chen, Yu Pfefer, T. Joshua Biomed Opt Express Optical Coherence Tomography In optical coherence tomography (OCT), axial resolution is one of the most critical parameters impacting image quality. It is commonly measured by determining the point spread function (PSF) based on a specular surface reflection. The contrast transfer function (CTF) provides more insights into an imaging system’s resolving characteristics and can be readily generated in a system-independent manner, without consideration for image pixel size. In this study, we developed a test method for determination of CTF based on multi-layer, thin-film phantoms, evaluated using spectral- and time-domain OCT platforms with different axial resolution values. Phantoms representing six spatial frequencies were fabricated and imaged. The fabrication process involved spin coating silicone films with precise thicknesses in the 8-40 μm range. Alternating layers were doped with a specified concentration of scattering particles. Validation of layer optical properties and thicknesses were achieved with spectrophotometry and stylus profilometry, respectively. OCT B-scans were used to calculate CTFs and results were compared with convetional PSF measurements based on specular reflections. Testing of these phantoms indicated that our approach can provide direct access to axial resolution characteristics highly relevant to image quality. Furthermore, tissue phantoms based on our thin-film fabrication approach may have a wide range of additional applications in optical imaging and spectroscopy. Optical Society of America 2013-06-14 /pmc/articles/PMC3704096/ /pubmed/23847740 http://dx.doi.org/10.1364/BOE.4.001166 Text en ©2013 Optical Society of America author-open |
spellingShingle | Optical Coherence Tomography Agrawal, Anant Chen, Chao-Wei Baxi, Jigesh Chen, Yu Pfefer, T. Joshua Multilayer thin-film phantoms for axial contrast transfer function measurement in optical coherence tomography |
title | Multilayer thin-film phantoms for axial contrast transfer function measurement in optical coherence tomography |
title_full | Multilayer thin-film phantoms for axial contrast transfer function measurement in optical coherence tomography |
title_fullStr | Multilayer thin-film phantoms for axial contrast transfer function measurement in optical coherence tomography |
title_full_unstemmed | Multilayer thin-film phantoms for axial contrast transfer function measurement in optical coherence tomography |
title_short | Multilayer thin-film phantoms for axial contrast transfer function measurement in optical coherence tomography |
title_sort | multilayer thin-film phantoms for axial contrast transfer function measurement in optical coherence tomography |
topic | Optical Coherence Tomography |
url | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3704096/ https://www.ncbi.nlm.nih.gov/pubmed/23847740 http://dx.doi.org/10.1364/BOE.4.001166 |
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