To facilitate Augmented Reality (AR) displays suitable for all-day-long usage, technologies are anticipated to realize compact form factor, low power consumption without compromising key aspects such as field-of-view (FOV), brightness, resolution, and uniformity. The balance among those requirements is crucial for creating a better AR experiences that are both comfortable and visually appealing for extended use. One of the challenges, FOV-resolution-form factor trade-off is addressed by using a MEMS based micro display panel, Digital Micromirror Device (DMD) in diffractive image steering mode. The DMD is paired with synchronized and short laser pulse illumination and a prism array expands FOV. This setup facilitates steering images into one of the multiple diffraction orders in a time sequential manner. The FOV is horizontally increased by fivefold. The vertical FOV is increased by twofold by incorporating illumination multiplexing. The resulting FOV reaches 30 degrees horizontally and 12 degrees vertically, all while sustaining a resolution of 1.86 arc minutes per pixel. This method increases FOV without sacrificing resolution nor increasing the form factor of micro display panel.
|