Artifact removal in FD-OCT with a B-M mode scanning technique : Condition on the transverse step

One of the main drawbacks of Fournier-domain optical coherence tomography is its inability to differentiate between positive and negative locations relative to the zero-delay position. In the recently proposed B-M mode scanning technique, these artifacts are removed by introducing a transverse modulation between successive A-scans followed by a Fourier filtering in the transverse direction. This paper deals with the relation between the transverse step size and the efficency of artifact removal. This relation is illustrated with measurements performed on an onion with different transverse step sizes and different focusing optics. These experimental results are used to support a proposed criterion for the transverse step. The criterion aims at insuring efficient artifact removal while limiting the amount of oversampling in the transverse scan.Un des principaux probl\ue8mes pos\ue9s par la tomographie par coh\ue9rence optique \ue0 domaine de Fourier (TCO-DF) est son incapacit\ue9 \ue0 faire la diff\ue9rence entre les endroits positifs ou n\ue9gatifs par rapport \ue0 la position de d\ue9lai z\ue9ro. Dans la technique de balayage en mode B-M r\ue9cemment propos\ue9, ces art\ue9facts sont \ue9limin\ue9s en introduisant une modulation transversale entre des A-scans successifs, suivie d\u2019un filtrage Fourier dans la direction transversale. Dans le pr\ue9sent article, on traite de la relation entre la taille du pas transversal et l\u2019efficacit\ue9 de l\u2019\ue9limination des art\ue9facts. Cette relation est illustr\ue9e gr\ue2ce \ue0 des mesures r\ue9alis\ue9es sur un oignon avec diff\ue9rentes tailles de pas transversal et diff\ue9rentes optiques de focalisation. Les r\ue9sultats exp\ue9rimentaux sont utilis\ue9s pour appuyer un crit\ue8re propos\ue9 pour le pas transversal. Le crit\ue8re vise \ue0 assurer une \ue9limination efficace des art\ue9facts tout en limitant la quantit\ue9 de recouvrement du balayage transversal.Peer reviewed: YesNRC publication: Ye

Artifact removal in Fourier-domain optical coherence tomography with a piezoelectric fiber stretcher

Peer reviewed: YesNRC publication: Ye

Common Path swept-source OCT interferometer with artifact removal

Peer reviewed: YesNRC publication: Ye

Artifacts removal with a piezoelectric fiber stretcher in Fourier domain OCT

Peer reviewed: YesNRC publication: Ye

On the speckle size in optical coherence tomography

Peer reviewed: YesNRC publication: Ye

Recovering distance information in spectral domain interferometry

This work evaluates the performance of the Complex Master Slave (CMS) method, that processes the spectra at the interferometer output of a spectral domain interferometry device without involving Fourier transforms (FT) after data acquisition. Reliability and performance of CMS are compared side by side with the conventional method based on FT, phase calibration with dispersion compensation (PCDC). We demonstrate that both methods provide similar results in terms of resolution and sensitivity drop-off. The mathematical operations required to produce CMS results are highly parallelizable, allowing real-time, simultaneous delivery of data from several points of different optical path differences in the interferometer, not possible via PCDC

Toward better treatment of clogged arteries

Real-time detailed monitoring of angioplasty balloon deformation may lead to improved medical devices to treat hardened artery walls.Peer reviewed: YesNRC publication: Ye

Using a piezoelectric fiber stretcher to remove the depth ambiguity in Optical Fourier Domain Imaging

Peer reviewed: YesNRC publication: Ye

Étude de la dispersion chromatique différentielle dans un interféromètre fibré hectométrique dans le cadre du projet OHANA

Nous présentons les résultats de l'étude de la dispersion chromatique différentielle entre deux fibres optiques unimodales en silice d'une longueur de 300 mètres. Ces fibres sont destinées à relier 2 télescopes du mont Mauna Kea à Hawaii dans le cadre du projet Optical Hawaiian Array for Nanoradian Astronomy (OHANA)

Experimental validation of an optimized signal processing method to handle non-linearity in swept-source optical coherence tomography

We evaluate various signal processing methods to handle the non-linearity in wavenumber space exhibited by most laser sources for swept-source optical coherence tomography. The following methods are compared for the same set of experimental data: non-uniform discrete Fourier transforms with Vandermonde matrix or with Lomb periodogram, resampling with linear interpolation or spline interpolation prior to fast- Fourier transform (FFT), and resampling with convolution prior to FFT. By selecting an optimized Kaiser-Bessel window to perform the convolution, we show that convolution followed by FFT is the most efficient method. It allows small fractional oversampling factor between 1 and 2, thus a minimal computational time, while retaining an excellent image quality.Peer reviewed: YesNRC publication: Ye