The modulation transfer function of an optical coherence tomography imaging system in turbid media

Nano and Multifunctional Materials Group, National Physical Laboratory, Teddington, TW11 0LW, UK.
Physics in Medicine and Biology (Impact Factor: 2.76). 05/2011; 56(9):2855-71. DOI: 10.1088/0031-9155/56/9/014
Source: PubMed


In this paper we describe measurements of the contrast transfer function, modulation transfer function and point-spread function of an optical coherence tomography (OCT) imaging system through scattering layers having a dimension-less scattering depth over the range 0.2-6.9. The results were found to be insensitive to scattering density, indicating that these measurement parameters alone do not well characterize the practical imaging ability of an OCT instrument. Attenuation and increased noise floor due to optical scattering were found to be the primary imaging limit and the effect of multiple scattering on OCT resolution was negligible.

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