![]() We take advantage of the phase stability within each B-scan and digitally generate a low-resolution OCT signal. The novel decorrelation-based transverse flow velocimetry, developed specifically for LS SD-OCT, extends the current dynamic light scattering flow speed measurement techniques. The image reconstruction method for recovering the diffraction-limited lateral resolution has been validated using different test objects such as standard resolution target, microbeads phantom, and different biological tissues imaged ex-vivo. In addition, we show that spatial-spectral crosstalk and chromatic aberrations can be efficiently suppressed by registration of monochromatic aberration corrected sub-band tomograms. We demonstrate that phase destruction can be minimized with appropriate optics alignment. We show that interference-induced phase destruction, spatial-spectral crosstalk, and chromatic aberrations are the three primary artifacts obscuring diffraction-limited resolution restoration with standard DAO in images acquired with the broadband LS SD-OCT system. Cornea epithelial cells, sub-basal corneal nerves, keratocytes in the stroma, cornea endothelial cells, palisaded of Vogt (POV) in the limbus, limbal epithelial cells between the POVs, and hyperreflective line structures underneath POVs are resolved in the 3D images within a limited depth range.ĭigital adaptive optics (DAO) is commonly used to correct the monochromatic wavefront aberrations in heterodyne imaging techniques. The motion artifacts are not noticeable in most volumetric images. The system's performance was evaluated by imaging in-vivo a healthy volunteer's cornea and limbus. The central sensitivity of the system is 92 dB near the zero optical delay with a 6 dB rolloff depth range of 0.78 mm. The novel LS SD-OCT system combines a broadband light source and an ultrafast area camera to achieve a nearly isotropic spatial resolution of ~2.3 □m in free space and an image acquisition rate of up to 3000 frames/second. ![]() In addition, a novel flow velocimetry method is developed for extending the LS SD-OCT system's functionality. This thesis addresses these challenges by developing: (i) a broadband line-scan (LS) spectral-domain (SD) OCT system that combines micrometer-scale spatial resolution and ultrafast image acquisition rate (ii) an image reconstruction method for restoring the diffraction-limited lateral resolution of the LS SD-OCT system along a large depth range. However, the application of OCT for in-vivo volumetric cellular resolution imaging of the human anterior eye is challenging due to artifacts induced by involuntary eye motion and the contradictory requirements for high lateral resolution and extended depth of focus. Optical coherence tomography (OCT) is an optical interferometric technique for non-invasive contactless imaging of the cellular-level structures of biological tissues. ![]()
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