One such device, coined Droplet, essentially redirects light from one source to another, while also serving as a physical interface for tablet-based tasks.

ENGADGET: Droplet and StackAR bring physical interface to virtual experiences, communicate through light (hands-on)

Until now, the existence of such a device -- which works by splitting light in a way that points to its source -- has only been hinted at in fleeting literary mentions.

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