According to Patently Apple, a blog that scours the latest patents filed by the Cupertino giant, Apple filed a patent last week in Europe for an augmented-reality powered windshield system, which it termed a Heads-Up Display.

While innovations detailed in corporate patents often don’t see the light of day, some of the ideas that Apple is exploring are interesting. Notably, its AR windshield may allow passengers in different vehicles to conduct FaceTime calls with each other.

“In some embodiments, an augmented reality display system included in a vehicle enables visual communication between an occupant of the vehicle and a remotely located user, including an occupant of a separate vehicle,” Apple’s patent said.

Another feature could use internal sensors to detect stress in drivers and passengers by monitoring eye motion, heart rate, body posture, etc. The AR windshield would then automatically adjust its display to potentially reduce stress, although it’s not clear from the patent how the display would accomplish this.

Last month, Apple filed another patent for “personal comfort profiles” of passengers and autonomous vehicles. Apple’s technology would navigate an autonomous car in different ways, according to a passenger’s profile. The AR windshield might rely on similar technology, Patently Apple said.

Apple’s smart windshield may also use external sensors to detect the current speed as well as the posted speed limit, displaying both on the windshield.

Apple CEO Tim Cook has said little about the company’s plans to create technology for cars, including autonomous vehicles. The company has reportedly backed away from plans for an Apple car, providing instead technology that would power autonomous vehicles. Last year Cook acknowledged that Apple is working on car technology, but did not rule out building its own car.

Apple was initially reportedly aiming to release its own electric car by 2020, but a more recent report claims that the launch date has been pushed into 2021.