Engineers at the University of Cambridge have developed a new AR-HMD (Augmented Reality - Head Mounted Display) that allows a more realistic 3D viewing experience without the usual side effects of nausea or eye strain normally associated with this type of display.

The display is a high-quality accommodation-free head mounted display (aHMD) consisting of a scalable enlarged eye-box designed for a more comfortable AR experience. The advantage of the design over other head mounted display (HMD) architectures is that the narrow, collimated pixel beams projecting the images are unaffected by the eye’s natural focussing mechanism.

The HMD uses partially reflecting beam splitters to create an additional "exit pupil" (a virtual opening through which the light travels). Together with narrow pixel beams that run parallel to each other and do not spread in other directions, the result is a high-quality image, unaffected by changes in the eye's focus.
The results of a study with more than 50 participants between the ages of 16 and 60 (published in the journal Research) showed that the 3D effect is very convincing for objects from 20 cm to 10 m, that pictures and videos have a vivid colour and high contrast without recognisable pixels and none of the participants reported any eye irritation or nausea, even after prolonged use for a few hours or even a full day.
 
Video: Department of Engineering, University of Cambridge / YouTube

The high brightness achieved makes this HMD suitable for a variety of indoor and outdoor applications. Further research is focused on applications such as training, CAD, development, healthcare, data manipulation, outdoor sports, military and construction work. Work is underway to miniaturise the aHMD to the size of spectacles.