Information is power when a soldier is enveloped by the fog of war. Precisely locating the positions of both friends and foes is key for a mission to roll out both smoothly and without avoidable casualties. The US Army has just revealed its latest innovation, a head-up display system for soldiers called "Tactical Augmented Reality," or TAR.
The TAR system is a small, one-inch-by-one-inch (2.5 x 2.5 cm) eyepiece that is mounted on a soldier's helmet. The eyepiece overlays a map onto the soldier's field of vision, instantly offering target information and GPS-tracked data showing where the rest of their team is located.
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Designed to replace a soldier's handheld GPS device, the TAR device is also wirelessly connected to a tablet worn on a soldier's waist, and to a thermal site mounted on the their rifle. This means additional data, such as an image of the target or the distance to a target, can be displayed through the eyepiece. This visual data can also be wirelessly sent to the eyepieces of other members of the team.
The TAR is similar to another head-up display being developed by BAE Systems called the Q-Warrior. That device, which has already been field tested by the US Army, is a little bulkier than this system from CERDEC.

The main challenge CERDEC faced in developing TAR was finding a way to miniaturize a high-definition image to fit on such a small eyepiece and couldn't be achieved with commercial, off-the-shelf hardware. They have successfully created high-definition monochrome units that are bright enough to be used in daylight, and development of full-color units are well underway.
Take a look at a simulation of the new TAR device in the video below.
Source: US Army