Cars are already capable of driving and parking themselves while avoiding obstacles, but to do so, they need to see their surroundings. How do you know whether you’re maintaining a safe distance from vehicles around you when it’s dark outside, or when headlights can’t penetrate the fog? A new class of small, sensitive optical sensors could help.

Researchers at Fraunhofer Labs in Germany are developing optical sensors that can be mounted between a car's windshield and a rear-view mirror. The sensors collect images and analyze them to pick out hard-to-see spots, which can help a car when trying to park. The sensors can also determine weather conditions and ambient lighting, according to Fraunhofer. If a car knows it’s foggy outside, it can automatically turn on fog lamps or emergency flashers, helping the driver see and helping other motorists notice the vehicle.

Some pricey German cars have already been equipped with these systems, a Fraunhofer news release says. Researchers were determined to build a version that can last much longer — without burning out the LEDs and light detectors — enabling these types of sensors to become available in mass-market autos.