Clear, Holographic Optic Allows High-Definition Images in Augmented Reality Devices
Augmented reality devices enable people to view the world around them overlayed with data relevant to what they are seeing. Applications range from head-up displays on car windscreens showing speed, navigation, and safety information, to headsets worn by surgeons during operations providing them with live health data from the patient. The UK's National Physical Laboratory (NPL) has developed an optical component for augmented reality devices in partnership with London-based company TruLife Optics. The small, lightweight optic consists of a glass waveguide that contains two postage-stamp-sized holograms. The light is transmitted into the first hologram and then turned 90 degrees through the length of the waveguide, via total internal reflection, before hitting the second hologram and being turned a further 90 degrees so it is projected into the human eye. This allows for overlaid transparent images to be projected from the center of the optic in perfect focus. Images can be displayed in high definition, full color, and in 3D (with a different image for each eye).