High-speed line-field confocal optical coherence tomography

Line-field confocal optical coherence tomography (LC-OCT) is an optical imaging technique based on low-coherence interference microscopy that uses line illumination and line detection to generate tomographic images of semi-transparent samples with micrometer-scale spatial resolution. We present an LC-OCT system that achieves a threefold increase in acquisition speed compared with previously reported systems, without compromising image quality in terms of spatial resolution, contrast, or field of view. Through modifications to the experimental set-up, as well as changes and optimization of image acquisition and processing, the system captures vertical section images [1250 μm×500 μm, lateral (x) × axial (z)] and horizontal section images [1250 μm×500 μm, lateral (x) × lateral (y)] at a frame rate of 30 Hz. High-speed in vivo imaging of human skin is demonstrated with a resolution of 1.4 μm×1.1 μm (lateral × axial). No motion blur is observed during rapid scanning of large skin areas. Notably, the system allows visualization of capillary blood flow by imaging moving red blood cells.