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As an effective noninvasive method for glucose doesn't come into clinical realization due to the weakness of glucose
unique signal and complexity of background noise, a method based on a floating reference point and a measuring point,
where the diffuse reflectance intensity is insensitive and most sensitive to the variation of glucose concentration,
respectively, is applied. In this paper, the data processing method based on the information of reference point was
investigated to improve the precision of glucose sensing. The diffuse reflectance of intralipid solution with different
glucose concentration in different source-detector distances was obtained by Monte-Carlo simulation. And the radial
region selection of reference position and measuring position were discussed. Then in order to simulate the actual
measurement condition, the random noise and linear drift were added on the simulated spectra. And the spectra in the
proper measuring region corrected by that in the reference point were used to build the multivariate model. Further more,
the corresponding optical probe was designed according to the distribution of light intensity in the radial distance and an
in vitro experiment about intralipid solution with different glucose concentration was conducted to verify the effect of the
data correction based on the information from the reference point. Results showed that, three different measuring regions
should be determined in the wavelength of 1100nm-1700nm according to the wavelength characteristic of reference
point. And the measuring region should be about 0.2-0.3mm far away from the reference region. For the simulation and
in vitro experiment, after the correction by the information from the reference point, the prediction error for glucose was
reduced by 46.2% and 23.2%, respectively.
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