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bioRxiv · 10.1101/2025.06.12.659250

On-skin, micro-lens enabled camera module for speckle contrast optical spectroscopy/tomography

Quiroga Soto, A. F.·Cortese, L.·Verma, M.·Dannberg, P.·Tachtsidis, I.·Danz, N.·Durduran, T.
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Abstract

In this paper, we introduce a speckle contrast optical spectroscopy/tomography (SCOS/SCOT) configuration based on an integrated imaging approach exploiting 113 micro-objetives mounted on a commercial CMOS camera that operates without fiber coupling, suitable for direct skin contact measurements and simultaneous multiple source-detector separation acquisitions. This compact system was validated ex vivo on phantoms and in vivo by monitoring the blood flow on the forearm muscle of a healthy human subject. The measurements, performed at multiple source-detector separations and camera exposure times, demonstrate excellent agreement with the theory based on the correlation-diffusion model. In vivo data demonstrate the capability of tracking pulsatile blood flow with a high signal-to-noise ratio (>4 harmonics of the cardiac pulse frequency detected) and sensitivity to small changes in muscle blood flow. This micro-objective array-based design overcomes a key challenge towards wearable SCOS/SCOT devices.

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Quiroga Soto, A. F., Cortese, L., Verma, M., Dannberg, P., Tachtsidis, I., Danz, N., Durduran, T.. 2025-06-17. On-skin, micro-lens enabled camera module for speckle contrast optical spectroscopy/tomography. https://doi.org/10.1101/2025.06.12.659250

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