25.09.2015 change 25.09.2015

Scientists are preparing laser remote detector of alcohol in the car

Photo: Fotolia / Photo: Fotolia /

The police might soon be able to detect alcohol vapour inside a car without having to stop the vehicle. Scientists are working on a device that could greatly increase the effectiveness of police control.

"It will be a device for remote detection of vapours of alcohol in moving vehicles. It should not be confused with breathalysers the police use today. The role of our device is different. It only indicates a suspicion of alcohol in the car, which can be then subjected to a detailed inspection. The result of this test can not be directly used to punish drivers" - said one of the creators of the device, Dr Jan Kubicki from the Military University of Technology.

With this solution, instead of checking a huge number of cars at random, police will be able to stop only suspicious cars. Others - in which alcohol is not detected - will be allowed to pass freely. "The effectiveness of this method will be much larger than the current methods" - noted Dr. Kubicki.

The device, positioned on one side of the road, will emit two laser beams combined into a single track. They will travel through the side windows of a passing car and, reflected from the reflector set across the road, they will return back to the device, falling on the detector. One beam is absorbed by alcohol, and the other is not. The signals from the two beams are compared by the installed program that can qualify the car for control. In addition, device sensitivity can be set to a specific value. If this is exceeded, a signal will be sent to the terminal. "Fractions of seconds are enough to classify the car where the air contains alcohol as suspicious" - the researcher described.

A camera placed by the device registers approaching cars. A few hundred meters ahead, a policeman who already has test results and data of the car, will be able to stop the car for a thorough inspection. "Only then - after control - the police can draw conclusions and possibly decide to punish the driver" - said Dr. Kubicki.

Even a very low level – approx. 0.1 mg/l - is sufficient for the unusual alcohol detector to signal the presence of alcohol in the car. The result is given immediately.

"We tried to develop a device based on simple, proven and commercially available components and parts. In the prototype we used gas helium-neon laser, which was the best solution at the time. Due to this, our device is relatively large. Most importantly, to be able to use it, you need to know the parameters of windows in tested vehicles. For that reason - at least for now - our invention can not just be put on the road and used to check passing cars" - admitted the researcher.

But it can be used them in large transport companies, where the parameters of individual cars are well known. The cars could be checked when leaving or returning to base.

There is, however, a chance for a broad application of the invention. When scientists began to work on it, research was underway on so-called cascade lasers. Those lasers could not be used at the time, because they were only in the research stage. Scientists are already working on a new version of the device, which will use this new generation of lasers. "Based on our preliminary research we believe that in this new version we will be able to remove the aforementioned drawbacks: the device will be small and versatile" - said Dr. Kubicki.

PAP - Science and Scholarship in Poland, Ewelina Krajczyńska

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