Holograms closer to becoming a reality

Scientists at the University of Arizona have developed a rewrite-able material that could one day be used to store massive amounts of shifting holographic data.

According to Arizona U optical scientist Nasser Peyghambarian, the substance is likely to offer future applications in medicine and manufacturing, as well as in the entertainment industry.

“From day one, I thought about the hologram of Princess Leia and whether it can be brought out of science fiction,” Peyghambarian told Nature.com.

“[But now] we have shown that creating a dynamic hologram of the size and resolution of Princess Leia is a reality.”

As Peyghambarian explaines, the initial challenge of achieving true holographic quality was successfully overcome when the team managed to create material capable of recording and displaying 3D images with a two second refresh rate.

To be sure, Peyghambarian’s prototype system captures 3D information by filming an object from multiple angles – using a total of 16 cameras that each take an image of the object every second. 

The 16 views are subsequently processed into holographic pixel data by a computer that sends a signal to two pulsed laser beams, which then write the data into the recording material.

During the writing process, the two beams combine to create an interference pattern of light and dark patches in the recording material. 3D images are then reconstructed by firing another light at the pattern.

“In a static hologram, the physical properties of the recording material are permanently changed by this interference pattern, so the image can never be refreshed,” said Peyghambarian.

“In contrast, [our] team has developed a rewritable recording material from a combination of plastic polymers, dubbed PATPD/CAAN.”

Indeed, when the laser beams hit the copolymer, they cause electrons and other charge carriers within it to drift and gather in areas corresponding to dark and light regions of the interference pattern, creating a temporary recording.

This allows the stored image to be overwritten by the next round of image data to be displayed.

It should be noted that Peyghambarian and his team have already constructed and tested a 17-inch display with an ultra-swift refresh rate – generating a high-quality image, in conjunction with PATPD/CAAN, that changes almost in real time.