Researchers at the Massachusetts Institute of Technology have created a working prototype of a bidirectional LCD that allows a viewer to control on-screen objects without touching the screen.
The bidirectional LCD screen, which captures and displays images, eliminates the need for any external controllers or touch contact. Hello, Minority Report.
Ramesh Raskar, Matthew Hirsch and Henry Holtzman created the prototype at MIT's Media Lab along with Douglas Lanman of Brown University.
Called the BiDi Screen ("bye dye," short for bidirectional), the device works by building on traditional touchscreen input. That technology works by using arrays of optical sensors that are interlaced with a panel’s pixels to detect multiple points of contact with the surface.
But to incorporate air gestures instead of simply touch, the researchers added a sensor layer of photodiodes behind the liquid crystal layer.
The LCD screen can switch between display mode -- serving as a backlit LCD display, just like your computer monitor or television -- and capture mode, where it can detect air gestures, in real time.
In capture mode, the screen functions like a pinhole array to capture the angle and intensity of light passing to the sensor layer (the backlight is disabled). By correlating data from multiple views across the sensor array, the system images objects -- such as your hands -- that are located beyond the display surface to determine their distance from the display.
Add software to pair air gestures with on-screen objects, and you've got yourself Minority Report-style interaction.