Drunk Person Screening using Eye Thermal Signatures

Temperature distribution on the eyes of drunk persons is studied by means of thermal infrared images. The sclera and the iris are of the same temperature for the sober person, while for the intoxicated person, the sclera temperature increases. Consequently, only the thermal images from the drunk persons are necessary for intoxication screening. Forty-one participants drank in a controlled alcohol consumption procedure. Their breath alcohol concentration was above the threshold of 0.2 mg/L of exhaled air, which corresponds to about 0.5 mg of alcohol per cubic centimeter of blood. Histogram modification algorithms were employed to prove that for 36 among the 41 intoxicated persons, the sclera becomes hotter. The Student t-test verified with over 99% confidence the drunk discrimination capabilities of the procedure. The forensic science potential contribution of the method is that face infrared imagery is available to the authorities for supporting intoxication in case of criminal actions.