Soon We'll Get To View Holograms On Our Phones And Tablets
HP is in the process of developing a 3D mobile display for images and video that can be seen from any angle, which they've just published and described in the journal Nature.
"This would mean you would see something like in 'Star Wars,' with the famous hologram of Princess Leia," study researcher David Fattal, of HP, told New Scientist. "If you were to display a 3D image of planet Earth, by turning around the display, you'd be able to have a view of any country on the globe."
HP's Raymond Beausoleil described some potential applications of the technology to New Scientist:
Perhaps an approach like this could be used for low-cost 3D signage. We believe the technology has important applications in enterprise, related to the visualization of complex data, perhaps even imagining molecular configurations for pharmaceuticals.
Plus, 3D is just plain fun. HP says the display should be easy to manufacture, because it’s based on existing LCD technology.
Displaying images in 3D
Our brains’ visual system interprets light coming into our eyes by combining the two images coming from our two separate eyes — which each have a slightly different view, separated by about 2.5 inches. To see something in three dimensions, a display needs to mimic those two separate views and send them to each eye separately.
According to MIT’s Technology Review:
Videos displayed on the HP system hover above the screen, and viewers can walk around them and experience an image or video from as many 200 different viewpoints — like walking around a real object.
In comparison, the Nintendo 3DS only has one viewpoint that can create a 3D moving image, so the gamer needs to keep their head at exactly the right spot to see an image in 3D.
Conventional 3D displays — like those in theaters or on 3D TVs — use special glasses to filter images to the right or left eye to trick our brain into seeing the image as three dimensional.
Usually to do this a display needs spinning mirrors or lasers or other such fancy things. This new technology has no moving parts and uses the display from a normal LCD screen — the kind currently found on laptops, TVs, phones, and tablets.
"Conventional 2D displays have pixels that send light in all directions. A 3D display needs pixels that send light in carefully constrained directions, so that different light reaches each eye and the viewer’s two eyes thus see different images on the screen," Neil Dodgson, a researcher from the University of Cambridge who wasn't involved in the study, wrote in a News & Views commentary in Nature.
To do this the display uses “nanopatterned” grooves in the backlight of the display that create directional pixels that send off light in different directions. The screens are as thin as half a millimeter.
Though the display is thin, it’s pretty complex. Using these nanopatterned grooves, the light from the backlight is directed through the display’s color filters, polarizers, and shutters which create the image. This is similar to how normal displays work, but this takes it to the next level.
The tiny grooves in the display scatter the light in very specific directions — hence the name “directional pixels.”
The number of directions the hologram is visible from is determined by the number of grooves in the display. They can make static images that can be seen from 200 angles, while videos at 30 frames per second can be seen from 64 viewpoints.
The display works best with computer-created images — to create images for the hologram would need 200 separate images — seen from each of the angles.
"A 3-D interface for a cell phone or laptop might display different windows next to each other, or architects could use a tablet to show a 3-D model to a customer, instead of building a physical model,” Fattal told MIT’s Technology Review. “Or you might use a smart watch to view Google Maps in 3-D."
Here are the display prototypes in action: