Holographic Near-eye Display with Expanded Eye-box

摘要

Holographic displays have great potential to realize mixed reality by modulatingthe wavefront of light in a fundamental manner. As a computationaldisplay, holographic displays offer a large degree of freedom, such as focuscue generation and vision correction. However, the limited bandwidth ofspatial light modulator imposes an inherent trade-off relationship betweenthe field of view and eye-box size. Thus, we demonstrate the first practicaleye-box expansion method for a holographic near-eye display. Instead ofproviding an intrinsic large exit-pupil, we shift the optical system’s exitpupilto cover the expanded eye-box area with pupil-tracking. For compactimplementation, a pupil-shifting holographic optical element (PSHOE) isproposed that can reduce the form factor for exit-pupil shifting. A thoroughanalysis of the design parameters and display performance are provided.In particular, we provide a comprehensive analysis of the incorporationof the holographic optical element into a holographic display system. Theinfluence of holographic optical elements on the intrinsic exit-pupil andpupil switching is revealed by numerical simulation and Wigner distributionfunction analysis.