Visualiser

From Tardis Wiki, the free Doctor Who reference

The Visualiser (also known as the Visualiser Eye, and referred to by Amy Pond as a "Dalek Librarian") was a piece of Dalek technology used in Kaalann to monitor the universe. It appeared to be a giant Dalek eyepiece. It could also connect to the eyepieces of every nearby Dalek and could scan for intruders. (GAME: City of the Daleks)