What Is a HUD (Head-Up Display)?

Article summary 

• Head-up displays (HUDs) project essential driving details like your speed, navigation instructions and safety warnings directly onto your windshield to help you keep your eyes safely on the road.
• While manufacturers originally installed this helpful technology only in luxury vehicles, you can now find HUDs in mid-range cars, electric vehicles and affordable aftermarket units.
• Major automakers like Ford and Toyota are currently developing innovative HUD features, including portable sun visor devices and distance-based displays, to make your future driving experience even safer.

Modern drivers deal with many potential distractions—phones, entertainment systems, cabin climate controls and more. Vehicle manufacturers have spent years refining ways to reduce these distractions and keep a driver’s hands on the wheel and their eyes on the road.

In recent years, steering wheels have been outfitted with entertainment system controls, cruise control and smartphone features to help ensure your hands never have to stray from the wheel. Now, they are working on ways to keep you from ever having to look away from the road with the introduction of head-up displays (often mislabeled as heads-up displays).

Imagine being behind the wheel and never having to look down to see your speedometer or double-check your navigation screen. With a head-up display, you won’t need to. 

How does a head-up display work?

The term head-up literally means “eyes forward.” The technology was originally developed for military aviation purposes during World War II, although the first system in operational service wasn’t available until 1961. It allowed pilots to view targets and flight information without needing to look down.

Today, a head-up display projects key driving information onto the windshield so drivers can see it without ever needing to take their eyes off the road. Thanks to modern technology and a transparent screen, this information can be projected without impeding the driver’s view of the road.

HUDs rely on small projectors built into a vehicle’s dashboard, tiny mirrors and specially treated surfaces to project images into your sightline without blocking your view of the road. The result is a clear, easy-to-read display that keeps your attention where it should be: on the road.

These displays are also customizable. You can adjust brightness, enable daytime/nighttime settings and adjust the position of images for maximum comfort.

What information does a HUD display?

The information on display will vary from system to system, but there are a few constants that you can expect:

• Speed – This allows you to see how fast you’re going without having to look down at your speedometer.
• Posted speed limits – Additionally, you will see the posted speed limit to ensure you’re not speeding.
• Navigation – Turn-by-turn prompts will guide you to your destination without you having to glance toward your phone or an installed navigation device.
• Safety warnings – These include collision and lane departure warnings.
• Call screening and media information – You’ll see who’s calling, what artist is playing on the entertainment system and volume controls.

HUDs and accessibility

HUDs were initially installed in luxury vehicles, but manufacturers are now expanding to mid-range vehicles and EVs as the technology continues to evolve. More consumers will have access to the technology, which, in turn, should lead to safer roads.

If your vehicle doesn’t come with a HUD installed, there are several aftermarket options available for you to purchase. These options typically plug into your vehicle’s power outlet or send data from your smartphone to a dash-mounted display. These dash-mountable units either project information onto your vehicle’s windshield or onto a separate transparent screen also mounted to the dashboard.

These aftermarket systems, while affordable, do have their drawbacks.

• The information displayed is not as robust as it is in pre-installed systems.
• The display is harder to see in daytime driving if projected onto your windshield. Pre-installed HUDs rely on specially treated or laminated windshields to reduce glare and other visual impairments, but aftermarket options typically do not include a film, so bright, direct sunlight could make the display harder to see.

What’s next for HUDs?

Both Ford and Toyota are working to revolutionize HUD technology. Ford has filed patents for a portable HUD that can be mounted to your sun visor. Their goal is to eliminate the need to project images onto glass while providing traditional HUD information and to include additional safety features like peripheral motion detection. As a bonus, Ford’s HUD would be portable, allowing drivers to move it from vehicle to vehicle.

Meanwhile, Toyota has patented a HUD that strategically displays pertinent information based on distance rather than displaying everything on one flat plane. This means that if something enters your vehicle’s path, existing car technology will assign a distance to it so that the drivers’ eyes can interpret order of importance and react in real time.

Are HUDs worth it?

HUDs are still a growing technology. Though they are still being refined, HUDs are easy to use and help keep drivers’ eyes on the road. For some, the displays may be hard to read, but it might be worth considering in your next vehicle purchase as the technology continues to improve and accessibility grows.