Infrared camera with sensor could make road traffic safer

Washington, July 7 (ANI): Infrared cameras with newly developed sensors can even function at room temperature, thus making road traffic safer.

It is known that infrared cameras can see more than the naked eye, but cameras for the long-wave infrared range have the disadvantage that the sensor requires constant cooling, which adds to the cost and complexity of the device.

Now a new type of detector has been developed which functions at room temperature.

Driving at night could be safer if infrared cameras are employed for better vision.

The problem is that infrared cameras for the wavelength range above five micrometers like it cold - the sensor has to be constantly cooled down to about minus 193 degrees Celsius.

This is now set to change as research scientists at the Fraunhofer Institute for Microelectronic Circuits and Systems IMS in Duisburg have succeeded in producing an imaging sensor for the long-wave infrared range that functions at room temperature.

"We could be the first in Germany to offer this technology," said Dr. Dirk Weiler, scientist at the IMS.

At the heart of the IRFPA (Infrared Focal Plane Array) sensor is a microbolometer - a temperature-sensitive detector that absorbs long-wave infrared light.

To produce a two-dimensional image, several microbolometers are combined to form an array. If the microbolometer absorbs light from a heat source, its interior temperature rises and its electrical resistance changes.

A readout chip then converts this resistance value directly into a digital signal. Previously this was not possible without a further intermediate step - normally the electrical pulse is first translated into an analog signal and then digitized using an analog/digital converter.

"We use a very specific type of converter, a sigma-delta converter, in our imager. This has enabled us to produce a digital signal directly," explained Weiler.

As complex and costly cooling is no longer required, further areas of application become feasible beyond the automotive sector.

"Mobile devices in particular should benefit from the new development," said Weiler.

The fact that the cooling mechanism is no longer needed not only saves weight.

The battery power available and therefore the operating time of the mobile device increase because no energy is needed for cooling.

The potential uses of mobile infrared cameras include firefighting, where they could detect hidden hotspots or locate people in smoke-filled buildings.

Initial laboratory tests with the new sensor element were successful. The research scientists have already been able to produce a number of infrared images. (ANI)