Rancang Bangun Alat Ukur Kadar Gula Darah Non-Invasive Berbasis Sensor Fotodioda

Abstract

A non-invasive blood glucose meter has been invented before by using light dependent resistor (LDR) as its sensor. This glucose meter has not generating accurate data because LDR is susceptible to noise. Photodiode sensor has more specific wavelength spectral response than LDR, so it can be more resistant to noise. The purpose of this study are to design a non-invasive glucose meter by using photodiode as its sensor and test it on blood glucose variations. The main component of this tool are photodiode sensor, signal conditioning circuits, and microcontroller ATmega328P. This tool is tested by measuring blood glucose level and seeing its correlation with the output voltage from the circuit. The result showed that the light intensity as represented by output voltage, will actually changed when the value of blood glucose changed, following polinomial equation y = 0,0014 x2 - 0,6652 x + 139,34. Coefficient of correlation R2 = 0,9544 showed that x has a real effect toward y, so it can be concluded that photodiode has been functioning properly as non-invasive blood glucose meter’s sensor. The accuration and precision value of this glucose meter are 98,92% and 97,41%.