The use of alcohol breath analyzers to immobilize a car if the driver is over the limit is becoming accepted. In Sweden, workers can be obligated to use the measuring devices as part of an employment contract. Some areas in Australia and Canada have introduced requirements on people convicted of a drink driving offense to have the instruments installed in their cars before their license is reinstated.
Methods of detection are based on non-dispersive infrared spectroscopy. Breathe from the subject is passed through a measurement cell where a broadband IR source is used to emit light through the cell to a detector. The detector uses IR optical filters to filter the light into an active channel at the absorption wavelength of the target gas and a reference channel. In simple terms, the light intensity at the detector decreases as the alcohol concentration in the chamber increases.
In order to measure gases at particularly small concentrations or very quickly, a high-sensitivity detector is required. The L220X1810, manufactured by Laser Components, is a dual-channel, current-mode sensor with a responsivity of 120000 V/W. The device is housed in
a standard T0-39, 4-pin package. The sensors have long expected lifetimes, making them suitable for this fit-and-forget application.
Back to Products
