Optical absorption glucose measurements using 2.3-μm vertical-cavity semiconductor lasers

Continuous glucose monitoring has been shown to help diabetes mellitus patients stabilize their glucose levels, leading to improved patient health. One promising technique for monitoring blood glucose concentration is to use optical absorption spectroscopy. This letter proposes the use of thermally tunable 2.3-mu m vertical-cavity surface-emitting lasers to obtain blood absorption spectra. The partial least squares technique is used to determine the glucose concentration from the spectra obtained in aqueous glucose solutions.