Now cops can scan for drunk drivers using Infrared Technology. Originally developed to help diabetics check their sugar level without the nasty needle prick. The device generates a beam of infrared (IR) radiation and channels this through optical fibres into a cradle designed to attach to a forearm. When a suspect’s arm is placed in the cradle, the infrared light penetrates to a depth of 5 millimetres and the reflected light is picked up by a bunch of IR sensors. The beam is constantly moved over the skin to avoid burning it. The reflected beam is combined with the original one to create an interference pattern. This will change depending on the amount infrared absorbed, which will depend on levels of alcohol in the blood.

The Infrared Blood Alcohol Test is certainly better than the breathalyzer.
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