Windscreen Head-Up Display (W-HUD)

Definition and Technical Principle

W-HUD (Windscreen Head-Up Display) represents the second generation of in-car head-up display technology. By utilising the vehicle's front windscreen directly as the projection medium, it relies on optical reflection principles to project driving data—such as vehicle speed, turn-by-turn navigation, and ADAS alerts—into the driver’s line of sight, creating a virtual image that appears to float over the road ahead. Unlike Combiner HUD (C-HUD), which uses a dedicated transparent combiner screen, W-HUD integrates seamlessly into the vehicle's cockpit architecture, delivering a wider display area and a longer virtual image distance.

Core Technology: Ghosting Elimination and Distortion Correction

The primary engineering challenge of W-HUD lies in resolving double imaging (ghosting) caused by the dual-layer construction of automotive windscreens. Because a windscreen comprises inner and outer glass plies sandwiching a PVB interlayer, light reflects off both surfaces to produce a primary and a secondary ghost image. To overcome this, W-HUD-equipped vehicles must be fitted with wedge-shaped PVB laminated glass—a tapered interlayer that aligns the reflected light paths from both glass surfaces into the driver's eyes, effectively eliminating ghosting. Simultaneously, high-precision free-form mirrors are employed to correct optical distortion caused by the windscreen’s curvature and rake angle, ensuring a crisp projection with a wide field of view and an extended virtual image distance. In terms of Picture Generation Units (PGU), TFT-LCD remains the dominant technology in the W-HUD segment, commanding nearly 100% market share.

Market Positioning and Current Adoption

W-HUD is currently the mainstream choice in the automotive HUD market. Industry data from January 2026 shows that W-HUD accounted for 66.8% of factory-fitted HUD installations in the domestic market. The technology is also accelerating its penetration from premium models into mass-market segments priced between RM150,000 and RM250,000. In terms of technical specifications, W-HUD typically offers a field of view (FOV) of 5° to 7.5° and a virtual image distance of 2 to 3 metres, mainly serving to project static data such as vehicle speed. However, some drivers have noted usability drawbacks, such as reduced legibility under direct sunlight and eye strain caused by constantly refocusing between the road and the virtual display. With AR-HUD installations surpassing the one-million mark for the first time in 2026—recording year-on-year growth of over 35%—W-HUD is gradually ceding its market share to this next-generation technology.