Augmented reality is quickly becoming more integrated into everyday usage, such as smartphone apps that can identify landmarks, constellations, and more. Head-worn goggles, like Google Glass can superimpose computer-generated images onto your direct view of the physical world. But, moving your eyes back and forth between a 2D image on the screen and a 3D world in front of you can cause eye strain, particularly for short distances viewing. To combat this, a new device being developed by scientists at the University of Arizona, Tucson, and the University of Connecticut, Storrs, is minimizing this visual discomfort by superimposing 3D images instead of 2D onto views of the real world.

The lightweight, high-performance device, called an optical see-through head-mounted display might one day allow a doctor to see computed tomography images overlaid on a patient's abdomen during surgery, they say.

To create the 3D image, the researchers developed a technology called microscopic integral imaging display. In this technique, a tiny, high-resolution screen produces views from different perspectives of the 3D image you want to superimpose. The views then combine to reconstruct a scene that is sent through a specially shaped optical lens, called a freeform eyepiece, and into the eye. The lens, based on freeform optics, also allows you to directly see the real-life scene before you.