Towards Occlusion-Aware Multifocal Displays

The human visual system uses numerous cues for depth perception, including
disparity, accommodation, motion parallax and occlusion. It is incumbent
upon virtual-reality displays to satisfy these cues to provide an immersive
user experience. Multifocal displays, one of the classic approaches to satisfy
the accommodation cue, place virtual content at multiple focal planes, each
at a diff erent depth. However, the content on focal planes close to the eye do
not occlude those farther away; this deteriorates the occlusion cue as well
as reduces contrast at depth discontinuities due to leakage of the defocus
blur. This paper enables occlusion-aware multifocal displays using a novel
ConeTilt operator that provides an additional degree of freedom — tilting
the light cone emitted at each pixel of the display panel. We show that, for
scenes with relatively simple occlusion confi gurations, tilting the light cones
provides the same eff ect as physical occlusion. We demonstrate that ConeTilt
can be easily implemented by a phase-only spatial light modulator. Using a
lab prototype, we show results that demonstrate the presence of occlusion
cues and the increased contrast of the display at depth edges.