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SD-OCT Base Unit Chapter 5: Imaging Artifacts
Rev E, November 7, 2018 Page 41
5.4. Multiple Scattering
When imaging highly scattering material, a large portion of the photons returned to the detection system have
been scattered multiple times from travelling into the sample until exiting. Since OCT visualizes the relative
travelled path lengths of photons, signals from multiple scattered photons are shown deeper in the image than
physically present.
Figure 52 Schematic of a Setup to Show the Influence of Multiple Scattering
Multiple scattering is intense in paper. For illustration of this artifact, a setup as depicted in Figure 52 is imaged.
Here, a piece of paper is placed over a glass substrate.
Figure 53 OCT Image Showing Multiple Scattering
In the OCT image (see Figure 53), one can clearly see that the paper appears to be very thick. This apparent
thickness is induced by the relatively long travel of photons that are scattered multiple times before finding their
way back into the detecting aperture.