Digital Signage Trends: 3D
Despite the fact that 3D displays and projectors are growing in popularity, it was noticeably absent from InfoComm 2011 (though it was featured as a special interest). One of the biggest arguments within the 3D world right now is between active and passive glasses. For the human brain to perceive a three-dimensional image, each eye needs to see a different signal. Active 3D uses glasses with shutters in them. About sixty times a second the shutters close and then open and each eye alternates. Everything is linked to the TV so that the right eye image is displayed while the right eye piece is open on the glasses. Then it switches for the left eye image.
Passive 3D is what the movie theaters use. The same image is projected on the screen using two projectors set slightly apart. The glasses have polarized lenses so that each eye can only receive the image designed for it. This is also the same technology employed by the Runco with the Constant Stereoscopic Video (Runco is a subsidiary of Planar Systems).
Even though home theater 3D technology is progressing well, the reliance on glasses to perceive the depth means that signage applications won’t work. Outfitting every passerby with a set of glasses isn’t practical or possible. On the horizon is a glasses-free 3D technology. The effect is achieved by the use of a lenticular lens, which spreads the image out horizontally. Think about that little hologram embedded in most credit cards and you know, basically, what a lenticular lens does. The problem with glasses-free 3D is that it sacrifices resolution for viewing angle. Displays can only show so many pixels – if you show two 3D images on a screen with 1920 pixels of horizontal resolution, you’ve divided it so that each image gets 960 pixels. The more you divide, the lower the resolution.
As displays get higher in resolution, glasses-free 3D will become an option for digital signage applications, but for now it’s not quite ready for prime time.