Optical Coherence Tomography 3D measurements in vivo

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Optical Coherence Tomography3D measurements in
vivo
Tomasz Bajraszewski
Faculty of Physics Nicolaus Copernicus
University Torun, Poland
ICPS 2003
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Overview

• brief introduction to the OCT technique
• construction of Spectral OCT
• needs for 3D in vivo measurements
• results

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Brief introduction to OCT technique

• OCT non invasive, non contact cross-sectional
  imaging modality.

• Main parts of the system
• broadband source of light (high spatial, low
  longitudinal coherence)
• Michelson interferometer
• detection unit.

• Two types of OCT
• Time-domain OCT
• Fourier-domain (Spectral) OCT

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Construction of Time-domain OCT
1. Time-domain OCT
PC
light source
beam splitter
moving mirror !
z
photodiode
z
object
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Construction of Spectral OCT
2. Spectral OCT
PC
CCD camera
light source
beam splitter
reference mirror
diffraction grating
X scanner
driving unit
object
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2D classical OCT image
x axis
z axis
rabbit eye in vitro with a contact lens
human eye fovea in vivo
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Requirements for 3D OCT imaging
Two X-Y scanners
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Requirements of 3D OCT imaging
ultra high speed CCD camera
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Requirements of 3D OCT imaging
Electronic driving unit
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Requirements of 3D OCT imaging
Visualization software (LabVIEW)
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Results profilometric visualization
9 digit of the ruler
X-scans 110 Y-scans 50 Meas. time 6s
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Results cube visualization
human iris in vivo
X-scans 110 Y-scans 90 Meas. time 11s
human finger skin in vivo
X-scans 110 Y-scans 90 Meas. time 11s
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Results projection visualization
human iris in vivo
X-scans 110 Y-scans 90 Meas. time 11s
250 XY planes added each other
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Torun Poland
- middle of Poland - 200 000 habitants - Nicolaus
Copernicus birth place
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OCT Group
Prof.. Andrzej Kowalczyk head
Dr. Maciej Wojtkowski
Dr. Piotr Targowski
MSc Tomasz Bajraszewski
Dr. Robert Zawadzki
MSc Maciej Szkulmowski
MSc Iwona Gorczynska
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THE END
Tomasz Bajraszewski
contact encore_at_phys.uni.torun.pl
web page http//www.oct.prv.pl