It is true that sensor technologies are not the first research area that comes to mind in the context of infection control. But the little electronic helpers can also be found in medical devices urgently needed right now, such as lung ventilators.

For this reason, the Fraunhofer EMFT clean room is not empty - even though the already high hygiene and safety standards have been tightened further. Dr. Lars Nebrich and his team support Heimann Sensor GmbH, a longtime customer, in the development and optimization of so-called thermopile infrared detectors. "These high-tech sensors are used for instance in non-contact IR clinical thermometers: they can reliably determine the body temperature of people even at a distance of 0.5 to 2 m (depending on the sensor type). Contactless temperature measurement can be used for access to buildings, for example: If the sensor detects an increased body temperature in a person, the system reacts with an optical and acoustic signal. In manual clinical thermometers, the sensors enable reliable fever control without medical staff coming into contact with patients.

However, almost even more relevant in the current situation is the fact that the sensors are also required for lung ventilators," explains the researcher. In lung ventilators, thermopile sensors are used in optical CO2 sensors to control the exhaled air.

Heimann is one of the world's leading manufacturers of these thermopile infrared detectors, and the demand is accordingly high. "If the supply of detectors were to come to a standstill, even more urgently needed medical equipment would be lacking in the current crisis areas," says Nebrich. The cooperation partners have therefore jointly decided to continue the work in the clean room. Nevertheless, it does not feel like "business as usual" for the team at the moment. "The health protection of our colleagues has top priority, there is no question about that", Nebrich emphasizes. Based on the instructions of the Bavarian state government and the Fraunhofer crisis management, only a greatly reduced core team is currently working in the clean room, so that the obligatory distance can be preserved at all times. Apart from this, even in "normal" times, work in the clean room is characterized by the strictest cleanliness requirements: the researchers generally work in special clean room clothing and the air is usually already low in germs, thanks to the specific air treatment with ultra-fine filter technology - similar to an operation room.

Developing thermopile sensors is a complex process that requires not only specific clean room infrastructure but also a lot of know-how and routine in building and processing so-called MEMS (micro-electro-mechanical systems). To optimize the manufacturing technology, Fraunhofer EMFT scientists are also working together with Heimann Sensor GmbH on the next generation of high-resolution infrared sensors. This could further increase the spatial and thermal resolution of such sensors while keeping production costs low.