Study On The Calibration Method For Non-invasive Blood Glucose Measurement With Different Skins

In the non-invasive blood glucose measurement,the physiological state of skin tissues may change randomly,which cause changes in optical parameters of the skins.In addition,the changes of the physiological state of skin tissues could be uncontrollable,which causes a large measurement deviation in the real measurement practices.In this thesis,a flexible calibration method for the human skin tests was proposed to correct the random measurement deviations.This method can flexibly adjust the calibration parameters based on the currently measured skin spectrum,and the parameters will be used to correct the current blood glucose results.This work would be significant for promoting the real application and development of non-invasive blood glucose measurements.The main work in this thesis is as follows:Firstly,the measurement theory of the position-differential spectroscopy is discussed,using the diffusion equation.And the formula to compute the optical parameter—effective attenuation coefficient is presented,and the glucose concentration prediction method can be performed by using this parameter.Among them,the linearity of the attenuation of diffuse light with the light source-detector separations is studied.Secondly,the effects of the skin changes on the blood glucose measurement are investigated,and a linear calibration method and its formula are proposed.The parameters for the calibration are discussed in case of the skin changes in their absorption coefficients and scattering coefficients.Finally,a method for estimating the linear calibration parameters for a changed skin is developed,by only using the current measured diffuse light spectrum of the skin.The method was validated by Monte Carlo simulations and human tests of oral glucose tolerance test(OGTT).The results show that the blood glucose measurement deviations were significantly reduced by using the calibration.In summary,the calibration method and its formula for non-invasive blood glucose measurement with skin changes are studied.For real use,we give a practical method to quickly estimate the calibration parameters.The method was validated by simulation experiments and human experiments.The research in this thesis could promote the future real application of non-invasive blood glucose measurement.