High-speed low-cost line-field spectral-domain optical coherence tomography for industrial applications

The applications of Optical Coherence Tomography (OCT) systems have been extensively explored in clinical settings and have attracted growing interest in other fields. Factors such as speed and cost are often prioritized over high resolution and power efficiency in industrial applications. Modern OCT systems typically operate at speeds between 20k-70k A-scans/s and are priced at least $50k. We report a line-field OCT with a high imaging speed of 430k A-scans/s, by operating a 2D camera in 8-bit mode, at a cost of $3.2k. The reported OCT system provides an axial resolution of 9 mu m in air and achieves a maximum on-axis signal-to-noise ratio and sensitivity of 68.8 dB and 88.8 dB, respectively. We demonstrate the practical use of the system by measuring, visualizing, and segmenting samples of Printed Circuit Boards, pharmaceutical tablets, and pea seeds.