摘要

Continuous non-invasive glucose monitoring makes the treatment and management of diabetic disease convenient. A non-invasive technique based on the frequency-modulated continuous-wave (FMCW) lidar technique that detects the scattering coefficient of the tissue is proposed. Compared with the traditional glucose measurement method based on optical coherence tomography, the FMCW lidar system has the advantages of simple and compact structure without moving parts, and is easy to realize portable apparatus. It mainly consists of a near-infrared semiconductor tunable laser and a detector, using heterodyne technique to convert the signal from time domain to frequency domain. A mathematical model of the system of sawtooth-wave modulation is established. Factors that affect system resolution are analyzed. Monte Carlo simulations have been performed on the tissue phantoms to investigate the slope of the system signal spectrum under different glucose concentrations. The simulations show that the system signal slope decreases 35% with a glucose concentration increment of 20 mmol/L, which agrees well with the scattering coefficients calculated by Mie theory. Proof-of-principle simulations and the experiments suggest that the FMCW method has a great potential as a convenient tool for non-invasive glucose measurement.

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