Continuous-depth augmented-reality display device

Near-eye displays with focus cues attract a lot of attention from display society since they can provide more immersive and comfort experience. However, there are several challenging issues to implement near-eye displays with focus cues. First, most prototypes still suffer from the contrast or resolution degradation which is drawback in reconstructing continuous focus cues. Second, providing multiple focus cues usually involves complex or large optical design that prevent comfort experience. Third, rendering process for layered structures demands a large computation load so that it is hard to realize real-time operation. Here, we will investigate several ideas to solve or mitigate these challenges. Foveated retinal optimization enhances the central contrast by considering human visual characteristics. After a calibration process, foveated retinal optimization could be employed without a gaze tracking system because pupil location, gaze direction, and distribution of optical nerves are correlated. Hybrid multi-layer displays are a convincing approach to achieve advantages of additive and multiplication displays. Combining additive and attenuated layers, hybrid multi-layer displays have relatively small form factor and higher brightness while providing continuous focus cues within the range of 1.8 diopter. Recently, we conceived a novel prototype that supports a large number of layers within the large depth of field. This system provides semi-original contrast, large depth of field, and quasi-continuous focus cues at 60 frames per second. We believe this approach may open a new possibility for near-eye displays for representation of continuous depth.