The arrival of software-defined vehicles (SDVs) will bring with them a reimagining of the cockpit experience. A transition from analogue buttons to digital technologies has been underway for more than a decade. So far, that has largely meant LCD touchscreens similar to a tablet. However, this approach could prove a mere stopgap on the road towards a more radical reinvention of the dashboard.
In January 2025 at CES, Hyundai Mobis unveiled its ‘world-first’ holographic windshield display (HWD): a head-up display that is projected onto and spans the width of the windshield. Designed in collaboration with German optical company Zeiss, the company’s HWD promises a wholly unique form factor and opens up a range of unique software-enabled possibilities.
Eye of the beholder
Fundamentally, the HWD concept is similar to that of a conventional projection display, which consists of a projector and a screen. The image projected is displayed on the screen, and light is transmitted to the human eye through scattering reflections. “But in the case of our HWD, a holographic optical element (HOE) serves as the screen,” explains Minho Shin, Principal Research Engineer for the HUD Optics Team at Hyundai Mobis. The image displayed on the windshield is generated by three separate projectors, all of which are integrated directly into the dashboard.
A HOE screen is distinguished from typical projector screens by two key characteristics. First, it must allow for wavelength selectivity: it only diffracts certain wavelengths of light—such as red, green, and blue—to ensure fast transmission rates and a high level of transparency. This minimises latency and prevents the display from obstructing the driver’s view of the road. It also prevents the distraction of other road users, as only vehicle occupants can see what is displayed. The HOE must possess a thickness of less than 100µm to make this possible.
The second characteristic is the ease of light distribution control. “HOE can control the emission angle and light distribution through its diffraction properties,” says Minho. In practice, this means the HOE can send different sets of visual information to multiple locations at once, allowing for unique and customised experiences for two vehicle occupants. What the driver sees on the dashboard, the front-seat passenger cannot, and vice versa. For example, the passenger can enjoy private entertainment offerings like movies or video games without the possibility of distracting the driver.
Reimagining the cockpit experience
Another driver benefit of the HWD is minimised eye movement. By placing key information like state of charge, speed and directions directly on the windshield, the driving experience is inherently safer because it helps keep the driver’s eyes trained on the road. When looking at the HWD, the driver retains clear visibility of the road in their peripheral vision. Key pieces of information, such as state of charge, will be similarly visible in the peripheral vision. In addition to aiding vehicle safety, however, it is also more convenient: the driver only needs to look away from the windshield when they need to do something, like adjusting the route or changing their music playlist.
More broadly, the HWD helps to facilitate a software-driven reimagining of the cockpit’s entire design. “This innovation is a game-changer for creating a seamless cockpit,” says Minho. Placing the majority of the infotainment experience on the dashboard allows the user interface to be simplified down to a small integrated touchscreen or a handful of integrated buttons.
Minho speculates that the touchscreen could even be abandoned entirely in favour of an AI-powered voice assistant or a deeper integration with the user’s smartphone. This more minimalist approach would not only facilitate a more spacious cockpit design but also create a clear “SDV aesthetic” due to the lack of visible hardware. This, it is hoped, would help to communicate visually what an SDV is and how it differs from a conventional vehicle in the eyes of consumers.
Facilitating future software
The integration of HWD into Hyundai’s vehicles could also help the automaker develop new and differentiating software offerings for its customers. Some of these are part and parcel of the integration of light distribution control, such as multi-screen environments tailored to the person viewing them and real-time data visualisation in the driver’s line of sight. “You could also use software to turn the windshield display into a part of the vehicle interior, providing personalised user interfaces that allow users to tweak the theme, background, and widget layout of the display to match the driver or passenger’s personal preferences,” remarks Minho.
This innovation is a game-changer for creating a seamless cockpit
As both HWD technology and autonomous driving become increasingly advanced, more radical software solutions may become possible. By achieving SAE Level 5 autonomous driving, it will no longer be necessary for a driver to keep their eyes on the road. “Eventually, we expect that the entire windshield could be transformed into a display using HOE, allowing you to essentially use the space like a personal movie theatre,” says Minho. However, he advises that this is not something Hyundai Mobis is currently working on.
By helping to maintain drivers’ attention on the road and creating a sleek and spacious cabin interior while delivering wholly unique software offerings, Hyundai Mobis believes its HWD technology could help differentiate SDVs. Pre-development of the technology will be completed in 2026, with its use in series-production vehicles set to follow as early as 2027.
