Venturebeat have found a 2010 patent filed by Sony which has striking similarities to that of the Nintendo Wii U.
Some extracts from the Patent below:
“A system for augmented video, the system comprising: a video source configured to provide video content to a video display; and a mobile device with an integrated video camera and display, the mobile device configured to: track a relative distance and direction of the video display using the video camera; determine a position coordinate of the mobile device using the tracked relative distance and direction; and render, on the integrated display, an object in a position based on the determined position coordinate of the mobile device.”
“A method for augmenting video, comprising: receiving a first position coordinate corresponding to a first user, the first position coordinate relative to a first video display; receiving a first view direction corresponding to the first user, the first view direction relative to the first video display; receiving a second position coordinate corresponding to a second user, the second position coordinate relative to a second video display; determining a direction and range from the first position coordinate to the second position coordinate; and rendering, on an integrated display of a first mobile device, an object based on the determined direction and range from the first position coordinate to the second position coordinate and based on the received first view direction. ”
Pictures from the Patent: