The noninvasive and optical only glucose monitoring investigation and analysis

For preventive medicine, regular glucose monitoring is the potential production to detect the possibility of diseases at an early stage. The noninvasive and optical only glucose sensor is more user-friendly for customers because of the advantages of small size, low cost, and easy operation. The near-infrared (NIR) glucose sensor is the most popular analytic method based on the glucose properties of overtones and combinational bands. For hardware setup, the 3D printing machine was used to fabricate the assembly components including the sample cuvette structure, the sample holder, and the laser diode stage, etc. The sample cuvette was composed of the structure with two square glasses with optical path length of 1, 1.5, 2 mm, and the optical component include the 1456 nm laser diode and the PD (photodiode). This paper investigates the glucose precipitation experiment (0-90 min), the response voltages with the different optical path lengths (1, 1.5, and 2 mm), and the response voltages with the laser power was 574, 798, 950, and 1045 mW/cm ² according to Beer-Lambert law, respectively. In the results, the different response voltages had not different when the precipitation time less than 90 min. In addition, the concentration of the glucose solution with the same optical path length and the same laser power was proportional to the response voltage. The optical path length with the same concentration of the glucose solution and the same laser power was inversely proportional to the response voltage. The laser power with the same optical path length and the same concentration of the glucose solution was proportional to the response voltage. The 1 mm optical path length and the 1045 mW/cm ² laser power had the best discrimination than the other optical path lengths and the other laser powers. The experiment results indicate that the shortest optical path length and the largest laser power are required for the best discrimination of the noninvasive and optical only glucose monitoring production.