Bosch engineers have re-imagined the sun visor as a transparent liquid crystal display (LCD) panel that uses algorithms to darken only the area where sunlight hits the driver’s eyes. The rest of the visor panel remains see-through for visibility. “The algorithm is really the magic behind the Virtual Visor,” Bosch technology expert Jason Zink told SAE’s Automotive Engineering prior to the product’s global unveiling at the CES 2020 in Las Vegas.

Led by Zink, a group of three powertrain engineers in North America created initial prototypes in their free time to secure funding for the concept, which transitioned – after approval – to the Bosch Car Multimedia division. “I’ve completely lost track of how many prototypes we’ve gone through,” software engineer Ryan Todd said, “but they can be broadly categorized into six major hardware generations.”

Seventh-generation hardware is expected to correspond to pilot-project fleet testing. The Virtual Visor is intended as a drop-in replacement for the traditional sun-visor, a ubiquitous vehicle staple since the 1920s when it appeared on the Ford Model T and other cars. Bosch’s prototype system features a transparent LCD panel comprised of hexagon-shaped pixels in a honeycomb grid and a driver-facing red, blue and green (RBG) camera to see sun-cast shadows on the face. “Artificial Intelligence is the enabler for the Virtual Visor,” Zink said. 

According to Todd, “The single most challenging aspect of this development was nailing down an algorithm that can simultaneously track the driver’s face and track shadows cast on the driver’s face, then use that information to update the display state of the Virtual Visor so that the shadow will line up directly in between the user’s eyes and the sun.”

Eyes, nose, mouth and other distinctive features of the face are AI-identified and software-tracked so that the visor’s algorithm-controlled hexagon pixels darken the visor only in the location where the sunlight hits the eyes. Each hexagon pixel shape is approximately 2 cm, while the average distance between the eyes is 6.5 cm. “One of the reasons to look for facial landmarks is to make sure that there is a sufficient shadow covering a visor user’s eyes,” Zink said.

Squares, rectangles, triangles and stripes were early pixel-shape contenders. “By making our pixels hexagonal, the resulting shape, when tessellated, is more circular. And that better matches your eye shape and the shape of the sun, so It makes sense to cast a circular shadow,” Todd said. Although Bosch officials declined to speculate on a timeline for production debut, the Virtual Visor is targeted as a traditional sun-visor replacement for light-passenger vehicles and commercial trucks.