Numerical dispersion compensation for Partial Coherence Interferometry and Optical Coherence Tomography

Abstract

Dispersive samples introduce a wavelength dependent phase distortion to the probe beam. This leads to a noticeable loss of depth resolution in high resolution OCT using broadband light sources. The standard technique to avoid this consequence is to balance the dispersion of the sample byarrangingadispersive materialinthereference arm. However, the impact of dispersion is depth dependent. A corresponding depth dependent dispersion balancing technique is diffcult to implement. Here we present a numerical dispersion compensation technique for Partial Coherence Interferometry (PCI) and Optical Coherence Tomography (OCT) based on numerical correlation of the depth scan signal with a depth variant kernel. It can be used a posteriori and provides depth dependent dispersion compensation. Examples of dispersion compensated depth scan signals obtained from microscope cover glasses are presented.

Design and validation of an angle-resolved low-coherence interferometry fiber probe for in vivo clinical measurements of depth-resolved nuclear morphology

“…Various dispersion compensation techniques have been developed in the past, based on either hardware or numerical correction. [34][35][36] We employ the latter approach with a second-order dispersion compensation. Let X (k, θ ) denote the cross-correlation term in Eq.…”

Dispersion cancellation in high-resolution two-photon interference

“…In more detail, the resolution of optical coherence tomography [9] using low-coherence interference (LCI) [10] is highly limited by the group-velocity dispersion (GVD) [11,12]; a resolution of 20 μm is typical in ophthalmography without dispersion compensation [13]. Since TPI can achieve better resolution than that of LCI, QOCT is expected to be an alternative to current OCT.…”

Resolution-enhanced optical coherence tomography based on classical intensity interferometry

“…We emphasize that even though the dispersion is not completely canceled out in the intensity-correlation signal, the relative resolution improvement remains the same also in dispersive media. Moreover, numerical methods similar to those used in conventional OCT [24][25][26] could be developed to compensate for the dispersion effects also in the case of the intensity-correlation signals.…”