Fiber-based polarization-sensitive OCT for birefringence imaging of the anterior eye segment

Abstract

Abstract:We demonstrate a prototype system of polarization-sensitive optical coherence tomography (PS-OCT) designed for clinical studies of the anterior eye segment imaging. The system can measure Jones matrices of the sample with depth-multiplexing of two orthogonal incident polarizations and polarization-sensitive detection. An optical clock is generated using a quadrature modulator and a logical circuit to double the clock frequency. Systematic artifacts in measured Jones matrices are theoretically analyzed and numerically compensated using signals at the surface of the sample. Local retardation images of filtering blebs after trabeculectomy show improved visualization of subconjunctival tissue, sclera, and scar tissue of the bleb wall in the anterior eye segment. 37. B. Braaf, K. A. Vermeer, M. de Groot, K. V. Vienola, and J. F. de Boer, "Fiber-based polarization-sensitive OCT of the human retina with correction of system polarization distortions," Biomed.

Estimation of Jones matrix, birefringence and entropy using Cloude-Pottier decomposition in polarization-sensitive optical coherence tomography

“…(1), we use Eq. (19) in [40] as the local Jones matrix, where we also processed the data by k-dependence correction. Since a product of two multivariate Gaussian distributions is also a multivariate Gaussian distribution [41], the statistical description in the above also holds for the local Jones matrix.…”

“…where the same notations in [40] are used in Eq. (13); sample ′ E  is a measured Jones matrix of the sample with k-dependence correction, and two Jones matrices that are axially separated for δz centered at a depth z are used.…”

Three-dimensional multi-contrast imaging of in vivo human skin by Jones matrix optical coherence tomography

“…The measurement range is primarily limited by the k-clock frequency, and also by the coherence length of the wavelength sweeping light source. The former limitation can be resolved by using a high-frequency k-clock generator [28], and the latter can be resolved by using light sources with a more longer coherence length, such as akinetic light source [53] or VCSEL light source [54].…”

“…The dermatological JM-OCT system was built from the passive-polarization-delay-based PS-OCT [22,27,28,43,44]. The schematic of our JM-OCT is shown in Fig.…”

“…The limitation of cumulative phase retardation imaging can be overcome by the birefringence measurement based on localized Jones matrix measurement [23][24][25]. Although the local Jones matrix measurement suffers from a low signalto-noise ratio and inaccurate phase-retardation and birefringence, these problems were recently resolved by birefringence and phase retardation estimation techniques that include the coherent averaging of the Jones matrix and/or Jones vector [26][27][28], eigen-value-based averaging [29], Jones matrix estimation based on the Cloude-Pottier decomposition [30], Muller analysis [31,32], a specially designed phase-retardation estimation function [33], and maximum a posteriori birefringence estimators [25,34,35]. These advances enabled the birefringence imaging of in vivo skin.…”