When this light hits, the plastic screen undergoes chemical reactions that temporarily record the most recent set of images in the data stream.
A particular color of light illuminates the plastic and -- voila! Light scatters in just the right way to recreate the original image. Then, the new plastic can be erased, creating a clean slate for the next image.
But unlike Princess Leia pleading for help, the new hologram can't float in space. Instead, Leia's image would appear to stick out from a screen's surface. "Star Wars was a great movie and we got a lot of feedback because of Princess Leia," says Arizona physicist Pierre-Alexandre Blanche. But the idea of a hologram hovering in mid-air is impossible. "You need a screen, a support to display the image."
Within a few months, the Arizona team hopes to create holographic video on a tabletop, where laser light shines up from underneath a table.
Before holographic devices hit living rooms, though, the holograms need to be bigger and faster. The researchers will have to upgrade their 50 hertz laser to one that operates at faster gigahertz speeds, scale up the size of the screen, and miniaturize their instrumentation.