As with the first system, those nearby see nothing more than a person waving their hands in the air, but to the wearer it all makes sense.
A third wearable technology used augmented reality to provide additional information about the world around. When a person approaches, the head-mounted device uses facial recognition to try to identify them, then projects their name and other details on a display.
So rather than scramble to remember someone's name, you can reply with a confident greeting and maybe a remark about the last time you saw them. It feels very futuristic and might raise concerns about privacy.
The same system can be used to translate text, on a restaurant menu for example. If you hold the menu up in front of you, the headset reads it and displays the translation.
All three technologies are research projects and there are no immediate plans to turn them into commercial products.
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