Nausea-free AR
Krishna Amin (St Catharine’s). September 29, 2019.Cambridge researchers at the Centre for Photonic Devices and Sensors and their colleagues from Huawei Technologies Duesseldorf GmbH have developed a new AR headset that eliminates nausea during use and improves image quality and the field of view, with implications for numerous industries.
Accommodation-free displays, also known as Maxwellian displays, keep the displayed image sharp regardless of the viewer’s focal distance. However, they typically suffer from a small eye-box and limited effective field of view (FOV) which requires careful alignment before a viewer can see the image. Their paper presents a high-quality accommodation-free head mounted display (aHMD) based on pixel beam scanning for direct image forming on the retina, using narrow, collimated pixel beams. It has an enlarged eye-box and FOV for easy viewing by replicating the viewing points with an array of beam splitters.
A prototype aHMD built using this concept shows high definition, low colour aberration 3D augmented reality (AR) images with a FOV of 36∘, a marked improvement on holographic displays, with poor image quality and a limited FOV of 4.9 degrees. The advantage of the proposed design over other head mounted display (HMD) architectures is that the high image quality is unaffected by changes in eye accommodation, and the approach to enlarge the eye-box is scalable. Most importantly, such an aHMD can deliver realistic three-dimensional (3D) viewing perception without vergence-accommodation conflict (VAC), which causes nausea, dizziness, eyestrain and inaccurate depth perception. Viewing the accommodation-free 3D images with the aHMD presented in this work was comfortable for viewers and did not cause the VAC symptoms commonly associated with conventional stereoscopic 3D or HMD displays, even for all-day use. Furthermore, the aHMD put forward in their paper delivers all the above improvements in a relatively compact system – previous solutions had resulted in impractically bulky optics. This new development in the world of AR has promising implications in almost every conceivable field, including education, sports and the military.
Their paper:
Pawan K. Shrestha, Matt J. Pryn, Jia Jia, et al., “Accommodation-Free Head Mounted Display with Comfortable 3D Perception and an Enlarged Eye-box,” Research, vol. 2019, Article ID 9273723, 9 pages, 2019.