Multiplane holographic augmented reality head-up display with a real-virtual dual mode and large eyebox

Automotive Augmented Reality Head-Up Displays

As the next generation of in-vehicle intelligent platforms, the augmented reality heads-up display (AR-HUD) has a huge information interaction capacity, can provide drivers with auxiliary driving information, avoid the distractions caused by the lower head during the driving process, and greatly improve driving safety. However, AR-HUD systems still face great challenges in the realization of multi-plane full-color display, and they cannot truly achieve the integration of virtual information and real road conditions. To overcome these problems, many new devices and materials have been applied to AR-HUDs, and many novel systems have been developed. This study first reviews some key metrics of HUDs, investigates the structures of various picture generation units (PGUs), and finally focuses on the development status of AR-HUDs, analyzes the advantages and disadvantages of existing technologies, and points out the future research directions for AR-HUDs.

Holographic multiplane augmented reality head-up display with switchable display modes based on polymer dispersed liquid crystal

The multiplane augmented reality (AR) head-up display (HUD) is important in improving driving safety and comfort. In this paper, we propose an AR-HUD with switchable display modes based on polymer dispersed liquid crystal (PDLC) and lens holographic optical elements (HOEs), which can provide two display modes: the dual-virtual-image mode and the virtual-real-image mode. The dual-virtual-image mode can produce two virtual images at different depths, which can provide a better sense of reality integration for the driver to improve driving safety and comfort. The virtual-real-image mode can produce one far virtual image and one near real image at different depths, and it provides a larger eye box (EB) for both driver and passengers in the car and a higher image contrast. The two display modes can be switched by an electronically controlled scattering module consisting of a pair of PDLC films. The proposed AR-HUD system is compact and equipped with multiplane display and mode-switching functions, and is expected to be applied in the future.