AR HUD allows vehicles to convey more data than a traditional dashboard. For example, the system could show how the car perceives the surroundings, detects hazards, plans routes, interacts with other technologies, and activates ADAS.
There are three kinds of HUDs. The existing standard models can display dashboard information on the windshield or in the driver’s field of vision. examined, individuals gain valuable insights about the road and vehicle conditions without diverting their attention from traffic.
In the future, advanced AR HUDs will project intricate graphics corresponding to real-world objects. For instance, on a foggy night, if the car’s thermal sensors identify an animal or human, they could highlight their presence to the driver. This way, even if a human eye can’t see the person through the fog, the driver can still react.
All these display systems share common building blocks:
– A data acquisition system comprised of sensors and engine control units (ECU).
– A data processing system that evaluates what information should be displayed and how to visualize it.
– A display system.
– Simple display systems might consist of static icons or graphics on a windshield. More complex display systems will present contextual animations to the driver. Finally, full AR display systems will integrate and adapt with the driver’s environment.
How Will AR HUD Assist Drivers in Adjusting to Autonomous Vehicle Technology?
As ADAS systems assume more control over the car, a HUD can enhance drivers’ understanding of these systems. As humans begin to realize that they need to take over the wheel less frequently, they will gradually gain confidence in self-driving cars and the technologies that enable them.
The challenge lies in the fact that designing, testing, and validating AR HUDs in real-world with a human-in-the-loop could be difficult, or even potentially hazardous. examined, virtual prototyping and development scenarios will play a critical role in reducing the time to market for this technology.
How to Develop HUD Systems
Conventional HUD development focuses on creating a clear image that doesn’t distract the driver. This means that the design must account for its integration into the car and its positioning relative to the driver.
It is difficult to anticipate what optical effects may arise during the design phase. Additionally, building physical prototypes could become expensive and delay development toward the end of the car’s design cycle.
Thus, engineers can utilize Ansys Speos to address optical challenges of these displays virtually. Using this method, defects that could be prevented early in the development include:
– Dynamic distortion
– Blurry images
– Ghosting
– Vignetting
– Stray light
Integrating AR into the display makes it more challenging to test and validate. The system needs to be dynamically tested to ensure it effectively interacts with the environment. For example, engineers have to guarantee that it recognizes the surrounding traffic elements and promptly displays pertinent information based on these inputs. As a result, the user experience (UX) and user interface (UI) of these systems encounter all of the optical challenges of a classic display along with the additional challenges arising from lag.
Thus, the AR system must be tested on the road, which implies that it will encounter all of the validation complexities associated with designing ADAS and AV systems. It is difficult to safely and practically control physical environments. For instance, if the system is tested on the road, it may not encounter all of the scenarios that could trigger potential defects.
The solution is for engineers to simulate the traffic and driving scenarios to evaluate the AR HUD in all conceivable scenarios, variables, and edge cases without compromising the safety of test drivers or people on the roads.
The Advantages of Virtually Testing AR HUD
Engineers will observe other benefits from testing their display systems using simulation. For instance, it allows them to consider the UX and UI early in development.
The design of the display will often be restricted by the development of the car’s windshield and dashboard. Therefore, by inputting these geometries into a virtual reality (VR), engineers can evaluate how these constraints impact the appearance and functionality of the system. As the geometries change development throughout, it doesn’t take engineers long to assess how they affect the display.
Through simulation, engineers gain an early understanding of how the HUD:
– Affects the field of view
– Distracts the driver
-Responses to latency, brightness, and movement
– Presents information
– Influences the driver’s response to new information, safety warnings, and edge cases
How to Virtually Test AR HUD System
The initial step in virtually testing the display is to have a prototype of its UI/UX software. Engineers utilize EB GUIDE arware from Elektrobit to create the AR content and embedded software for the HUD system.
First, engineers utilize Ansys VRXPERIENCE to develop a real-time physics-based lighting simulation that replicates the display of content. This simulation can also verify how sensors perceive the environment to ensure the proper functioning of the data acquisition system.
Then, Ansys VRXPERIENCE HMI enables engineers to immerse themselves in their HUD designs within a digital reality environment. Subsequently, the embedded software can be included in the testing and validation process, allowing engineers to virtually design, evaluate, and test an augmented reality HUD prototype under real driving conditions.
For example, this setup allows to observe how sensor filtering can impact the performance of the AR HUD system. Due to human perception of movement, AR systems require a higher frequency of data collection compared to ADAS systems. Simulations can validate whether the vehicle motion tracking is adequate for the system to align its graphics with the real world and human vision.
Prior to embarking on a long journey, it is important to have a clear view of the road ahead and know the route. Head-up display technology embodies both of these concepts to enhance the driving experience.
HUD, a form of augmented reality, projects data onto a transparent display so that users do not have to divert their attention from their usual viewpoints. It was originally developed for military aviation as early as the 1950s, displaying altitude, speed, and targeting systems in the cockpit. This allowed pilots to receive information at eye level by looking straight ahead with their heads up, rather than having to shift their gaze to another piece of equipment.
HUD systems are increasingly being integrated into production cars’ windshields, typically offering displays for speedometer, tachometer, and navigation systems.
How does the head-up display work?
The workings of HUD technology often depend on the system used. Some vehicles employ transparent phosphors on the windshield that react when a laser is shone on them. When the laser is off, no information is displayed, but when it is on, the information is projected onto the glass. A projector built into the car’s dashboard projects a transparent image onto the windshield, utilizing a series of mirrors to reflect the image before magnifying it for legibility to drivers. This can be adjusted to meet their visual and height requirements.
The All-New Kona is equipped with a combiner head-up display.
For the first time in a Hyundai, the new combiner HUD of the All-New Kona directly projects relevant driving information into the driver’s line of sight. This allows for quicker information processing while maintaining focus on the road ahead.
The Kona’s HUD features an eight-inch projected image size at a two-meter distance and class-leading luminance of over 10,000 candela per square meter, ensuring optimal visibility in varying light conditions. It is activated by a button located next to the steering wheel and retracts into the dashboard when not in use. The HUD’s angle and height can be adjusted to ensure optimal visibility for each driver.
HUD in the Kona contributes to safe driving by displaying information such as speed, navigation commands, and the car’s fuel levels, as well as safety warnings from assistance systems such as Lane Keeping Assist and Blind-Spot Collision Warning. additionally, the HUD also projects information regarding the in-car radio and audio systems.
Enhancing Driver Safety and Experience
What is a head-up display (HUD)? This automotive electronic system projects vehicle and environmental data onto the windshield within the driver’s line of sight. By integrating speed, navigation, and ADAS alerts with the external view, this HUD technology helps drivers maintain focus on the road. HUDs are projected to reach a market value of USD 3,372 million by 2025, indicating their increasing significance in improving driver experience and safety in the automotive industry.
Technology is transforming the automotive sector. Driver assistance and surround-view cameras, previously exclusive to high-end vehicles, are now standard in many mid-range cars. HUDs are slowly following suit.
Moreover, Mazda offers HUDs in several vehicles. Instead of incorporating components into the dashboard with a dedicated windshield, Mazda3 and Mazda6 HUDs utilize a foldable plastic lens. MINI provides a similar system. However, this cost-effective approach restricts expensive the image size and location compared to windshield HUDs.
The Need for HUD
Head-up display technology minimizes eye movement and focus adjustments. The immediate flow of data reduces cognitive strain, enabling swift responses to driving conditions and hazards. For example, dual-focal HUDs optimize data processing and comprehension by separating critical driving metrics and navigational signals across visual planes. They can offer active driving assistance information at a distance of 25 meters from the driver and road information 2.5 meters away on two displays.
Accordingly, head-up display technology enhances situational awareness, reduces distractions, and accelerates information absorption. It has become an essential asset for vehicle safety.
HUD Types
Combined Head-Up Display (CHUD): The core of head-up display technology is CHUD. It directly shows basic driving information in the driver’s line of sight. Data is displayed on a clear screen or windshield through a simple projection mechanism. CHUD’s basic capability limits its interaction with real-time driving conditions and ADAS. CHUD displays may use TFT-LED panels and 2D flat displays. However, they require at least 20 liters of HUD volume, have low brightness and contrast, and lack distance perception.
Windshield Head-Up Display (WHUD): WHUD improves head-up display technology. This enhancement increases the display area for more complex information. WHUD can be easily integrated into the windshield, creating a more vivid information display without changing the focus length. WHUD systems are complex and require special windshields.
Because WHUD systems are fixed, they must be custom-designed for each vehicle model. WHUD displays can also use TFT-LED or DLP projection, but they may have a smaller virtual image, lower brightness and contrast , and no AR.
Augmented Reality Head-Up Display (AR-HUD): AR-HUD represents the latest head-up display technology. It overlays digital information on the real-world view. AR-HUD can display people and objects on the windshield and provide adaptive navigation signals that blend with the road ahead. In addition, it utilizes laser beam scanning, variable field of vision, virtual image distance, volume, and low power.
However, it’s important to note that AR-HUD systems require development costs and computing resources to process real-time data and create the augmented display, which may limit short-term adoption. The rich visualizations of AR-HUD may overwhelm some drivers, and it requires custom display choices to avoid information overload.
Projection Basics
Understanding “how HUD works” or “how does a heads-up display work” involves knowing how it projects navigation and vehicle statistics into a driver’s field of sight. A heads-up display uses a projector to display images on the windshield or combiner. Optical systems with lenses and mirrors sharpen and direct the presented information without causing distractions.
For example, the windshield HUD matches the glass’s curvature to display data as if it’s floating on the road ahead. This eliminates the need for drivers to look away from their environment. On the other hand, combiner HUDs use transparent LCD panels to reflect the display from a smaller area and are more compact. These systems utilize calibration to adapt the display to correct viewing angles and distances for clarity and readability in various lighting conditions.
Optical Combiner Functionality
The optical combiner functions as a selective filter and reflecting surface, aiding in HUD visibility. When considering “how does a heads-up display work,” the optical combiner also aligns the projected visualization with the driver’s closest line of perception for the best luminance. HUD systems using optical combiners utilize refined polymers and coatings to enhance light refraction and reflection, ensuring that the information is clearly displayed against the windshield view.
The combiner also adjusts the focal distance of the projected data so that drivers can see it as if it were moving ahead on the road. As a result, this configuration enhances readability in various lighting conditions and helps the driver stay focused on the road for safer driving.
The Picture Generation Unit
The picture-generating unit of a HUD utilizes optical technology to present information, which is essential to understanding how HUD works. A high-resolution projector with LED or laser light sources illuminates digital content to ensure that information is clearly displayed and directly, avoiding duplicate images under different lighting conditions.
Additionally, the image-generating unit of AR-HUDs superimposes dynamic visuals directly over the road view using real-time data from the vehicle’s sensors and navigation systems, providing improved situational awareness without distracting the driver. This hardware-software interaction delivers clear, actionable information directly into the driver’s field of sight, optimizing the user experience while combining real-world and digital stimuli.
Spotlight on FIC AR-HUD Features
Innovative Laser Beam Scanning (LBS)
LBS technology, a fundamental aspect of advanced head-up display technology, projects information using high-intensity laser light sources, providing exceptional visibility even in bright sunlight.
Meanwhile, lasers’ higher contrast (80,000:1) and brightness improve the readability of display content with sharper images and more colors. LBS can more precisely control light than standard HUD systems. This enables flexible adjustment of brightness in response to ambient light conditions, addressing the challenge of “how does a heads-up display work” under changing lighting conditions. examined, LBS maintains key driving information bright and easily readable.
Integration with ADAS
AR-HUD and ADAS from FIC use innovative optical projection and sensor technologies. The AR-HUD utilizes Laser Beam Scanning for projection, high contrast & brightness, 6-42 degrees FOV, 3-50M VID, 4L-20L volume, low power consumption , and ADAS-based with seven algorithms for road status mapping. It explains how HUD works by merging real-world and virtual data without diverting drivers’ attention from the road.
ADAS utilizes radar, lidar, and cameras to monitor and assess environmental variables, while the ECU makes decisions to enhance response times and prevent accidents. These technologies offer a comprehensive safety net, including but not limited to blind spot recognition, lane departure alerts, and adaptive cruise control. Find out more about FIC AR-HUD and ADAS by visiting FIC’s official AR-HUD page and FIC’s ADAS solutions.
While you drive, numerous distractions are vying for your attention—both on the road and inside the vehicle. The speedometer. Fuel levels. Traffic alerts and driving conditions. Valuable information to enhance your driving experience, but to view it, you must look down or away from the road.
What is a Heads-Up Display?
A heads-up display (HUD) is a type of augmented reality that presents information directly in your line of sight so you don’t need to look away to see it. Just as the name suggests, it helps drivers keep their eyes on the road – and their heads up.
What Are Applications for Heads-Up Displays?
While driving is the most commonly known application for heads-up displays, there are many uses for the technology. Anywhere an operator requires visibility to the real world and digital information simultaneously, a HUD can be beneficial. Piloted systems, such as aircraft, military vehicles, and heavy machinery, are all ideal use cases. In these situations, information is projected where it can be viewed by the operator without looking away from the road, sky, or task at hand.
Another common application for HUDs is video games. Augmented reality headsets utilize HUD technology to provide gamers with the ability to see through the game and into their physical environment. When used in this manner, they create a mixed reality where game play is overlaid with information about the player’s status, such as health, wayfinding, and game statistics.
The global use of telemedicine has also increased the adoption of heads-up displays in healthcare. Providing medical professionals with the convenience of hands-free operation, Head-Mounted Displays and Smart Glasses featuring HUD technology can be found in clinical care, education and training , care team collaboration, and even AI-guided surgery.
Types of Heads-Up Displays
Whether you’re a pilot needing to keep your eyes on airplane traffic or a gamer watching out for the edge of the coffee table, there are several types of heads-up displays designed to fulfill specific user requirements. Many factors, such as the environment , cost constraints, and user comfort, all play a role in selecting the appropriate type of HUD for the intended use.
While HUD types can vary to serve the industry and use case, most HUD types consist of the same three components—a light source (such as a LED), a reflector (such as a windshield, combiner, or flat lens), and a magnifying system.
All HUDs have a light source (Picture Generation Unit) and a surface reflecting the image. (Most often this surface is transparent to allow the user to see through it). In between the light source and reflecting surface, there is typically a magnifying optical system. The magnifying systems can be:
- One or several freeform mirror(s) magnifying the image
- A waveguide with gratings magnifying the image
- A magnifying lens (typically in aircraft HUDs)
- Nothing (some HUDs have no magnification)
- Benefits of HUDs
Heads-up displays project visual information within a user’s current field of view. This provides several key benefits:
- Enhances safety through improved focus and awareness
- Prioritizes and distills the most pertinent information at the right time
- Alleviates eyestrain caused by constantly changing focus
- Builds trust between autonomous vehicles and riders by demonstrating that the system and human share the same reality
How Does a Heads-Up Display Work?
Place the flashlight from your phone on a window and you’ll see both the light’s reflection and the world beyond the window. A heads-up display achieves a similar experience by reflecting a digital image on a transparent surface. This optical system provides information to the user in four steps.
- Image Creation: The Picture Generation Unit processes data into an image
- Light Projection: A light source then projects the image towards the desired surface
- Magnification: The light is reflected or refracted to magnify the beam
- Optical Combination: The digital image lands on the combiner surface to overlap the real-world view
To address the human element, HUD designers utilize simulation. By digitally testing and validating their models, they can proactively tackle various scenarios and technical obstacles, potentially without the need for expensive physical prototypes. These obstacles may include:
– Ghost images, warping value, and dynamic distortion
– Variations in human physiology such as head position and color vision deficiencies
– Changes in colors due to coated windshields or polarized glasses
– Contrast, legibility, and brightness of projected images
– Sunlight impacting legibility and visual safety
As vehicles become more technology-packed, the method of delivering information is also evolving. Analog gauges are disappearing, and screens are taking over, displaying a wide range of information from speed to comprehensive maps. Adding to this shift is the head-up display ; once a feature exclusive to luxury brands, it is now available in mainstream vehicles as well.
The Two Categories of Head-Up Displays
The most prevalent type of head-up display projects information onto the vehicle’s windshield. Depending on the automaker, the system can display various information including speed, navigation directions, and infotainment details. In some performance cars or models with manual transmissions, head-up displays provide shift indicators to suggest optimal shifting points. Certain brands such as Mazda limit the displayed information to speed, navigation directions, and the current road speed limit, while others like Mercedes-Benz, BMW, Toyota, and Volvo offer customizable information, including the color of the speed display.
To make head-up displays more accessible in affordable vehicles, manufacturers like Hyundai, Kia, Mazda, Ford, and Mini project information onto a pop-up plastic panel positioned just above the instrument cluster. The third-generation Mazda3 was among the first to feature this type of head-up display, followed by the current-generation Mini lineup. Hyundai introduced its first pop-up head-up display on the Kona and Veloster, while Kia recently added it to the Soul. The latest Ford Escape compact SUV also features this type of head-up display on higher trim levels.
Which Type of Head-Up Display is Superior?
Each type of head-up display has its advantages and disadvantages. The advanced windshield projection technology is more convenient as it positions the information higher up and directly in the driver’s line of sight, offering more surface area for displaying information without cramming it into a small space. However, this setup comes with a higher cost due to the specific glass required for projecting information onto the windshield, and some systems may be difficult to see when wearing polarized sunglasses.
Head-up displays projected onto a plastic panel are more cost-effective, but their adjustability is limited due to the smaller surface area. In some cases, the driver may need to look down slightly because the pop-up panel is not within their direct line of sight. One advantage is that these displays require a conventional windshield glass, reducing replacement costs in case of damage.
Should You Consider a Car with a Head-Up Display?
If you view a head-up display as a safety feature designed to keep your focus on the road instead of looking down at an infotainment screen, trying out the technology is sensible. However, some systems may reflect light even when inactive, and cost can also be a consideration. While head-up displays are worth looking into, they are not an essential feature.
What to Evaluate in a Head-up Display
Assess the level of customization to tailor the type and amount of projected data to your preference. Some individuals may prefer a simpler layout with minimal information.
Consider the surface area used on the windshield or plastic panel. Some head-up displays use a wider area to display more information.
Ensure that the projection can be adjusted to be within your line of sight.
If the head-up display projects onto a plastic panel, ensure that it does not necessitate looking down too much.
The Purpose and Functioning of HUDs
While this technology has long been utilized in the aviation industry, head-up displays have been present in cars for several decades—they were first introduced in the 1988 Nissan Silvia on Q trims and up, as well as the 1988 Oldsmobile Cutlass Supreme Indy Pace Cars—and have evolved to be highly practical.
Some are more effective than others, but overall, head-up displays have been a valuable technological advancement for the automotive industry, providing a wealth of information within the driver’s line of sight without obstructing their view forward. But how do they work in the first place?
Projection: Similar to their use in the first fighter planes, HUDs are designed to keep the user’s focus on the road or the airspace ahead by keeping their head up. To achieve this, a HUD utilizes a projector that is directed at a reflecting surface at an angle, ensuring that the projected light hits the viewer’s eyes based on the Law of Reflection, which states that the angle of reflection equals the angle of incidence.
The projector also needs to focus so that its reflected image is perceived to be farther away than the surface on which it’s being reflected, closer to visual “infinity,” due to the windshield acting like a lens. Hence, the image in the projector appears a bit fuzzy when viewed from angles outside the vehicle.
Combiner: The glass used to reflect the image from the projector is called a combiner or a beam splitter, and it may be the windshield itself or a separate piece of glass positioned in the viewer’s field of view. Regardless, it needs to be treated to ensure a bright display and prevent a “ghost” image. Sometimes the glass is tinted to make the HUD image stand out against the bright environment in front of the driver.
This tint can be laminated within the glass or added to the back of the windshield . Some manufacturers apply this tint across the entire windshield, while others do so only in the area where the image is projected. In the case of a separate, retractable combiner, the glass is usually treated as a whole and may be curved for focus and image distortion.
Ghost In the Display: Ghosting, where a second image appears within the combiner, is caused by unwanted refraction, a phenomenon that occurs when light is deflected by a medium instead of passing through it. This phenomenon is separate from the Law of Reflection and is responsible for bending light in water and creating mirages. Improperly designed glass combiners or overly laminated glass can cause this effect by bending some of the light from the projector at just the right angle to reflect back into the cabin, creating a ghost image for the viewer’s eyes.
To address this issue, modern windshields used in cars with HUDs are sometimes laminated with a wedge-shaped PVB layer between the glass in the area where the HUD is projected. The wedge shape of the PVB layer aligns the refracted-reflected-refracted light to line up directly with the normally reflected light from the projector.
Considering all of these factors, it’s why many manufacturers, especially those aiming to avoid the cost and complexity of a specialized windshield, opt for a retractable combiner instead of a specialized windshield. Some may find the amount of ghosting and low light reflection to be ” acceptably legible,” which may explain why some auto manufacturers implement HUDs more effectively than others.
The dashboards in cars are crucial for ensuring safe and smooth driving by providing important information such as speed, RPM, oil level, and warnings. However, with more data being displayed on multiple screens in cars, it can sometimes be challenging to see critical information. Additionally, looking back and forth between the dashboard and the road can be risky, particularly when drivers need to concentrate and keep their eyes on the road.
Head-up displays for drivers in vehicles
This is why head-up displays (HUDs) have gained popularity in the transportation industry recently, as they project essential information in front of the driver to reduce distractions.
There are two main types of head-up display technologies: Projected HUD and Emissive HUD.
Projected HUDs
Common projected HUD solutions include TFT-/micro-LED-display HUD and DLP projector HUD. When it comes to TFT-/ micro-LED-display HUD, two mirrors are used to project images from a micro-LED display, while the DLP projector HUD consists of a DLP projector, DLP optics, and HUD optics.
Here are the advantages and disadvantages of these two projected HUD solutions.
Pros of projected HUDs
The focal point can be adjusted, for example, to 3 meters ahead of the road. The eyes can refocus quickly when the driver switches from the road to the projected display, which typically floats 3 meters in front of the driver.
The projected content can be vivid and colorful.
The solution is well-established, as it has been available and tested in the automotive market for years.
Cons of projected HUDs
The setup is complex and takes up a lot of space (usually 7-10 liters) on the dashboard.
A special windshield/coating is needed.
The viewing angles are limited.
The projector shakes when the vehicle shakes, leading to blurry images.
They are not suitable for vertical windows and windshields, making them unsuitable for buses, RVs, trucks, or vans in most cases.
Emissive HUDs
As emissive display technologies progress, some serve as alternative solutions for creating next-generation head-up displays that do not need projected systems. The emissive display technologies that can be used for HUDs include micro-LED, TOLED, and LUMINEQ in-glass/polycarbonate displays.
These solutions utilize transparent displays to show information in front of the driver. The electronics and flexible cables are compact and hidden, while the display components are located outside the dashboard. Micro-LED arrays can be attached to the windshield or placed above the dashboard as a separate unit, such as TOLED. LUMINEQ in-glass/polycarbonate displays are laminated into the windshield.
Pros and cons of emissive HUDs
The focal point is the main difference between an emissive HUD and a projected HUD. The focal point of a projected HUD is adjustable and usually positioned a few meters ahead of the road, whereas the focal point of an emissive HUD is on the display, which is placed in the driver’s line of sight. This can be seen as a disadvantage or an advantage, depending on the driver’s preference. The projected information floating a few meters ahead of the driver allows the eyes to refocus more quickly, but some drivers may find it more distracting when combined with real-world road conditions.
Apart from the focal point, another significant difference is the amount of space required for the setup. In this aspect, emissive HUDs clearly come out on top. Their construction is straightforward and requires minimal space in the vehicle’s interior. Instead of a complex projection system, emissive HUDs only consist of compact electronics, a flexible cable, and a display. The electronics are small and take up approximately 0.3L of space on the dashboard, which is 20-30 times less than projected HUDs.
Additionally, emissive HUDs are more capable of withstanding shock and vibration. They are suitable for use in vertical windshields of commercial and industrial vehicles like trucks, buses, RVs, vans, cranes, forklifts, and tractors as they directly display information, unlike projected HUDs which usually require specific angles to project images effectively.
Out of the three emissive HUDs, LUMINEQ and mini-LED are constructed using inorganic materials, while TOLED is made using organic materials. Therefore, the performance of a TOLED HUD is significantly influenced by the environment, whereas the other two are resistant to external factors such as humidity, solar load, and temperature.
In terms of optical clarity and transmission, LUMINEQ HUD outperforms TOLED and mini-LED. It boasts 80% transparency, and the whole laminated stack can achieve over 70% overall transparency. In comparison, TOLED achieves 40% transparency, and mini-LED achieves 60%, depending on the density of LEDs in an array. LUMINEQ HUD provides excellent clarity with minimal haze, while the other two have issues with clarity and haze. The images from LUMINEQ HUD can be viewed from any angle, both inside and outside the vehicles.
Ford’s Lincoln division is the pioneer in adopting Continental’s new Digital Micromirror Device (DMD) head-up display (HUD) technology for production. By projecting symbolic representations of objects ahead of the vehicle, they are advancing towards offering augmented reality HUD, which is Continental’s ultimate goal.
Research conducted by the Virginia Tech Transportation Institute consistently indicates that the likelihood of a crash or near miss more than doubles when a driver takes their eyes off the road ahead. HUD technology can mitigate the need to divert attention by displaying selected information in the driver’s line of sight.
In 1988, General Motors became the first automotive manufacturer to incorporate HUD technology, originally developed for fighter aircraft. Early systems projected images from a cathode ray tube onto the windscreen or a pop-up screen integrated into the top of the instrument panel.
Subsequent systems utilized liquid crystal display (LCD), LED, or laser technology to project images, ultimately aiming to create virtual images that appear to be located beyond the front of the vehicle, reducing the need for the driver to refocus their vision to clearly perceive the displayed information.
In addition to displaying fundamental data such as speed and engine RPM, digital map data or camera technology can also allow the current speed limit to be displayed. Advanced active safety systems can provide data that enhances road markings, provides following distance alerts, and symbolically highlights obstacles such as pedestrians and cyclists.
Continental has been a prominent player in the HUD sector and announced in 2014 that they were developing an augmented reality HUD (AR-HUD) system with “near” and “status” projection distances and “remote” and “augmentation” projection levels.
Selected status information like current speed, speed limit, and the current setting of the Adaptive Cruise Control seem to be located near the front of the vehicle’s bonnet, while augmented representations of navigation symbols or hazards appear to be 65 feet to 330 feet (20 m to 100 m) ahead, as part of the road ahead.
The content is adjusted based on traffic conditions using inputs from camera and radar sensors, vehicle dynamics systems, digital map data, and GPS positioning. The system also supports other driver assistance systems such as lane departure warning.
Dr. Frank Rabe, head of the Instrumentation & Driver HMI business unit at Continental, stated that the Digital Micromirror Device (DMD) HUD is a step in the direction of AR-HUD.
“It is a significant achievement for the entire team that our digital micromirror device technology is going into production for the first time at Lincoln,” says Rabe. “Our solution bridges the gap between the classic head-up display and augmented reality head-up displays, providing a better image with a larger display area.”
The DMD, which is used instead of the previously employed TFT LCD technology, generates graphical elements in a manner similar to digital cinema projectors, integrating mirror optics and a picture generating unit. An intermediate screen and sequential color management result in brighter and sharper images than those produced by previous displays, making the Lincoln HUD one of the brightest and largest in its class.
The expanded display area allows for more information to be shown, reducing the need for the driver to shift focus to the instrument cluster, and remaining visible to drivers wearing polarized sunglasses.
Coincidentally, the first application of Continental’s DMD HUD was in the 2017 Lincoln Continental, and it is now available in the 2018 Lincoln Navigator.+
The Future of Head-up Displays
In modern automobiles, there are primarily two types of head-up displays (HUDs): one that projects data onto a glass or plastic panel extending from the instrument panel, and the more advanced version that projects data directly onto the windshield.
However, the basic operating principle remains consistent between these two types. A projector housed within the dashboard (typically situated in a large rectangular opening) generates an image that is then reflected by a series of mirrors.
Among these mirrors is a rotatable mirror, which enlarges the original image created by the projector, corrects any distortion, and enables the driver to modify the final display position on the windshield. After passing through the rotatable mirror, the image is reflected off the windshield (or a separate glass/plastic piece) into the driver’s field of vision.
For systems that project directly onto the windshield, a specially crafted windshield is necessary, designed with stricter tolerances to minimize double reflections.
As a result, if the vehicle is involved in an accident, a replacement windshield meeting OEM specifications must be used, as opposed to any third-party alternatives that might be easier to find.
Advantages
Similar to their counterparts in aviation, HUDs seek to decrease distractions and enhance visibility by positioning crucial information within the driver’s line of sight, minimizing the need for drivers to divert their attention away from the road and look down at their instrument panel.
Initial head-up displays were primarily focused on presenting speed; however, modern car versions are much more advanced, showcasing a range of information.
In addition to speed, this information can include everything from the tachometer, selected gear, navigation instructions, detected speed limits (as identified by the vehicle’s traffic sign recognition system), details from driving assistance technologies (like adaptive cruise control), and even media information such as currently playing songs.
Budget-friendly aftermarket head-up displays are now widely available in several retailers, including Supercheap Auto and JB Hi-Fi. These displays typically consist of bright LED screens that sit on the dashboard and reflect information onto the vehicle’s windshield into the driver’s line of sight.
Normally, these aftermarket displays are limited to showing speed data through an integrated GPS unit, or both speed and engine revs if connected to the vehicle’s OBDII diagnostics port.
The Apple App Store and Google Play Store also feature HUD ‘apps’ that promise to provide similar functionality when the user places their smartphone on top of the dashboard; however, the practicality and effectiveness of these apps is often questionable.
Augmented reality
One of the most significant advancements in head-up displays is the incorporation of augmented reality (AR) technology. In the context of HUDs, this allows features like navigation directions and road hazard alerts to be displayed as virtual ‘objects’ on the actual road being traveled.
For instance, in terms of navigation, directions for turns or which lane to merge into can appear virtually above the actual intersection or lane, resembling an arcade video game. This greatly enhances the driver’s contextual awareness of their driving surroundings by clearly visualizing the precise location of any hazards or navigation directions.
Specifically for navigation, the integration of AR directly into the head-up display is arguably a more efficient approach than layering it over a real-time camera view in the central infotainment system (similar to features offered by certain Mercedes and Genesis models), as the driver can keep their gaze forward.
Another notable aesthetic development in this area is the gradual emergence of color head-up displays throughout the industry, marking a shift from the standard monochromatic HUDs commonly found in many vehicles.
