Cars are running out of screens. The dashboard is a jumble of numbers, icons, indicator lights, and gauges. In some vehicles, the display built into the center console is bigger than our televisions in certain rooms at home. But drivers' and passengers' appetite for more information isn't subsiding, so the dashboard and entertainment console are about to get a companion: the windshield.

At the Detroit auto show, which runs until Jan. 25, you'll find demonstrations of cars with built-in projectors displaying speed, range, turn-by-turn directions, and other crucial data along the bottom of the windshield. Head-up displays—developed to keep fighter pilots' eyes on the sky rather than on the instruments in the cockpit—have existed in some form for cars since at least the 1980s, but they've mostly functioned as a novelty for high-end clientele. In the past year, however, HUD technology has made its way into some Mazdas and Priuses as a way to manage information overload for everyday drivers.

Automakers have been adding a flood of information designed to keep drivers safe—some requested by customers, others mandated by governments—but it risks having the opposite effect. As weird as it sounds, projecting text and graphics onto the windshield may be less distracting to drivers than forcing them to look down at cluttered in-car screens—or worse, their mobile phones. A HUD, which sits within the driver's line of sight, would be free of "check engine" and "change oil" lights, and only display the alerts a driver might need at any given moment. Hyundai, Toyota, and General Motors expect the HUD to go mainstream very soon.

King, Ian, and Dana Hall. "The Car Windshield Is Turning Into a Computer Screen." Bloomberg.com. Bloomberg, 22 Jan. 2015. Web. 14 Apr. 2015.