Adjustable and continuous eyebox replication for a holographic Maxwellian near-eye display

A Maxwellian display presents always-focused images to the viewer, alleviating the vergence-accommodation conflict (VAC) in near-eye displays (NEDs). Recently, many methods of improving its limited eyebox have been proposed, among which viewpoint replication has attracted a lot of attention. However, double-image, blind-area, and image-shift effects always happen in typical eyebox-replication Maxwellian NEDs when the eye moves between the replicated viewpoints, which prevents these NEDs from being applied more widely. In this Letter, we propose a method for designing a holographic Maxwellian NED system with continuous eyebox replication as well as flexible interval adjustment by changing the projection angles of the reconstructed images. Thus, holograms corresponding to the positions of different viewpoints are calculated to match the interval of the replicated viewpoints with the human pupil diameter, making it possible to eliminate or alleviate double-image or blind-area effects. Also, seamless viewpoint conversion in the eyebox is achieved by aligning the images of adjacent viewpoints on the retina via hologram pre-processing independently. These effects are verified successfully in optical experiments and have the potential to be applied in near-eye three-dimensional displays without VAC.