Microlens array-based high-gain screen design for direct projection head-up displays

Abstract

Head-up display (HUD) systems have been used in recent car models to provide essential information to the drivers while keeping their eyes on the road. Virtual image HUD systems have been the preferred method, but they have the drawback of requiring a large volume of space in order to accommodate the relay optics that creates the virtual image. This is especially significant as the desired field of view increases. Direct projection HUD systems have been developed with a separate stand-alone microlens array (MLA)-based transparent screen on the dashboard, offering a compact solution. In this paper, we propose a direct projection HUD system based on a unique, windshield-embedded see-through screen that uses minimal space under the dashboard, offering an elegant and compact solution to the HUD problem. The screen is based on MLAs with varying surface normal angles such that the light from the projector is directed to the viewer's eyes from all positions across the field of view. Varying tilts provide an efficient relay and high brightness even with a low-lumen output projector. The calculated screen gain is about 69 and the eyebox area is about 30 cm×30 cm.

Wearable and augmented reality displays using MEMS and SLMs

“…Fig1.e shows a light efficient semi-transparent screen to be used with pico projectors [5]. Such screens are essential for emerging augmented reality applications such as automotive head up displays, where display image needs to be combined with real world view.…”

High‐efficiency switchable optical elements for advanced head‐up displays

“…With the rapid development of high brightness yet compact display systems and increasing needs from the modern automobile industry, head‐up displays (HUDs), aimed at enhancing road safety and driving comfort, have been intensively developed in recent years . The very name “head‐up” precisely and concisely emphasizes the main benefit of this type of automotive display.…”

“…With the rapid development of high brightness yet compact display systems and increasing needs from the modern automobile industry, head-up displays (HUDs), aimed at enhancing road safety and driving comfort, have been intensively developed in recent years. [1][2][3] The very name "head-up" precisely and concisely emphasizes the main benefit of this type of automotive display. Useful driving information such as navigation instructions, adaptive cruise control data, and lane-departure warnings are directly projected to the driver's field of view (FOV).…”

Image quality affected by diffraction of aperture structure arrangement in transparent active-matrix organic light-emitting diode displays

“…The development of microprojection applications on wearable devices is popular research in this field. Many researches focus on stereoscopic 3D projection, bilateral projection function, or imaging quality improvement [17][18][19][20].…”