Video holograms

A new development in optical materials brings a sci–fi fantasy to life.

Ever since R2-D2 showed Luke Skywalker a flickering projection of Princess Leia, people have been obsessed with holograms. It has taken more than 30 years to turn sci-fi fantasy into a reality, but now an optical research team at the University of Arizona has reported the ability to transmit 3-D holographic video in almost real time.

Holography records the light reflecting from an object, then reproduces the pattern on a material to present a 3-D image of the original object. The researchers have developed a new type of plastic that allows the previously static image to be refreshed every two seconds, thereby giving a sense of movement, like in a film. According to project leader Nasser Peyghambarian, “the technology has the potential to show hundreds of perspectives.”

The team first chose various objects, including their own heads, and surrounded them with 16 webcams to capture multiple perspectives. The cameras then sent the images to another room where they were encoded into a fast-flashing laser. The laser pulsed the image onto their newly developed photo-reactive plastic where the light from the image gets turned into electrical charges and stored. The properties of the polymer allow the charges to move around, projecting the original image, and because the polymer can rewrite the image every two seconds, the static image easily turns into a moving picture.

Applications for what the researchers are calling “holographic telepresence” range from virtual business meetings to remote medical exams. The military is also interested — though they should remember the use to which Darth Vader put the technology.