The Problem with Heads-up Displays
Heads-up displays (HUDs) are systems that allow drivers to view important vehicle information while keeping their eyes focused ahead of them. At their most basic level, they function as projectors that use the windshields of cars (or planes) as a backdrop. They might contain information on speed, navigation, fuel use or any number of relevant data points.
Currently, all HUDs suffer from the same limitation: a small eye box. When drivers shift their field of view even slightly, all or part of the display becomes invisible to them. Researchers from the University of Arizona think they may have a solution to that problem. In a paper recently published in Applied Optics, the team presents a system that uses holographic optical elements to allow HUD users a larger eye box. The result is a drastically improved user experience—one in which viewers of the display don’t need to worry that shifting their posture a few inches could obstruct their view of crucial data.
Using Holography to Expand the Eye Box
In order to increase the size of the total display or the eye box using traditional HUD methods, the associated optical mechanisms must be enlarged. According to Colton Bigler, doctoral student and an author of the paper, that simply isn’t practical. “[It] takes up too much space in the dashboard,” he said.
To address this concern, his team tested a system using holographic elements instead of the traditional optical components of a HUD. These elements relay light from a small, computerized image to a glass canvas of sorts. The glass then funnels the light toward another holographic element that extracts the image and displays it directly onto the windshield in front of it. The result? An eye box that could be up to seven times larger than the original image, giving users the flexibility to adjust their seats and/or posture without losing the display. Check out the video below for a demonstration of how perspective shifts impact the holographic HUD.
Holographic HUDs: Coming Soon to Your Vehicle?
Bigler’s team feels confident that their improvements could be in widespread use within a few years. While their current focus is ongoing work with Honeywell on integrating the technology into airplane displays, there’s reason for optimism about it catching on in cars, too.
One point that automakers are likely to appreciate is that the requisite holographic components are good candidates for mass production. This, in turn, should make them cheap. In fact, using holography in standard car models shouldn’t require any equipment more expensive than what’s used in current HUD setups. The team says their larger display and eye box could be applied to a standard car windshield easily and economically.
While more testing is needed, the commercial potential of this technology could be too great to ignore. A system that creates a better user experience that is both cheaper and easier to implement than earlier alternatives? That’s usually a recipe for a successful marriage of technology and business.
Check out other cool hologram research with 3D Holograms that Float in Thin Air.