Multi-wavelength Optical Approach for Non-invasive Alcohol Detection

Alcohol acts as a central nervous system depressant and is classified as a psychoactive drug that impairs cognitive alertness and motor coordination. Driving after alcohol consumption slows reaction time in emergency situations and increases the risk of collisions. Although various technologies have been developed to measure alcohol concentration, many suffer from limitations such as sensitivity to environmental factors (e.g., temperature and humidity), hygiene concerns, and the need for periodic calibration. This study proposes an optical method for measuring alcohol concentration using near-infrared (NIR) spectroscopy. Statistical analyses were conducted across multiple wavelength regions to identify wavelengths with significant correlations to alcohol concentration. As a preliminary step, single alcohol solution samples were prepared using distilled water and ethanol. The optical properties of the samples were analyzed in the NIR wavelength range, and statistical indicators including the coefficient of determination (R²), p-value, and coefficient of variation (CV) were evaluated. The results identified specific wavelengths with statistical significance, and the application of mathematical modeling at these wavelengths enabled accurate estimation of alcohol concentration. This approach demonstrates the potential for non-invasive alcohol concentration measurement while minimizing hygiene and infection-related concerns for users.