Speckle in optical coherence tomography: simulation and experiment with a structured phantom
نویسندگان
چکیده
Speckle is an intrinsic feature of images acquired with any imaging system employing coherent wavefields. It manifests itself as a rapid fluctuation of the detected intensity (or field envelope) over the spatial extent of the image, conveying a granular texture. In optical coherence tomography (OCT), it is generated by the ‘coherent’ summation (i.e. on a complex amplitude basis) of multiple optical wavefields. These wavefields are backscattered from the sample arm of the OCT interferometer and are made to interfere with a reference wavefield at the detector. Interference is observed if their relative time delay is within the coherence time of the source.
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