Massachusetts Institute of Technology

Henry Holtzman

Ramesh Raskar

Douglas Robert Lanman

Matthew Waggener Hirsch

Roger G Kermode

A bidirectional screen alternately switches between a display mode showing conventional graphics and a capture mode in which the LCD backlight is disabled and the LCD displays a pinhole array or a tiled-broadband code. A large-format image sensor is placed behind the liquid crystal layer. Together, the image sensor and LCD function as a mask-based light field camera, capturing an array of images equivalent to that produced by an array of cameras spanning the display surface. The recovered multi-view orthographic imagery is used to passively estimate the depth of scene points from focus.

Bi-directional screen

A video-on-demand system divides video files into sequentially organized data segments for transmission and playback. Each segment is repeatedly transmitted in a looping fashion over a transmission channel. The rate of transmission is equal to or greater than the playback rate, and the lengths of the segments are chosen such that: (i) the receiver tunes into no more than a fixed number of channels (preferably two) at any one time; (ii) the receiver tunes into a new channel only after an entire segment has been received from a previous channel; and (iii) until a maximum segment length is attained, data is received from no fewer than two channels. The segments are sequentially presented even as new segments are being downloaded. When the display rate is equal to the transmission rate, it is found that the foregoing conditions are satisfied when the relative lengths of the segments form a modified Fibonacci sequence.

Growing community of inventors

W. Roxbury, MA, United States of America

Henry Holtzman