Japan's National Institute of Information and Communications Technology (NICT) exhibited a 200-inch naked-eye 3D screen that shows full-HD (1,920 x 1,080-pixel) video to each of the two eyes.
NICT developed the screen in collaboration with JVC Kenwood Corp. NICT has exhibited naked-eye 3D display systems at CEATEC since 2008 (See related article). Those systems and the latest screen use multiple projectors to drastically increase total pixel count so that smooth motion parallax can be realized while apparent resolution is kept at full HD. Motion parallax is a stereoscopic effect realized when the viewer sees different images depending on the angle from which the viewer looks at the screen.
The new system is different from the previous ones in that NICT increased screen size from 70-72 to 200 inches while keeping apparent resolution. It uses 64 projectors and has 57 parallaxes in the horizontal direction.
Density of images determines quality of 3D image
Commercially-available 3D TVs using special glasses realize 3D video by showing two images for the right and left eyes (as images seen from two different angles) at the same time (or almost at the same time). And many of the so-called naked-eye 3D TVs that do not require glasses show two to nine types of images for every angle.
On the other hand, the NICT's latest display system shows 57 types of images (as images seen from 57 different angles) at the same time and with a high density. At a point 5.5m away from the screen, the image changes each time when the viewpoint moves 2.3cm in the horizontal direction.
However, this density of images is available only when the angle of the eye to the screen is within 90±6.75°. At the point 5.5m away from the screen, the viewable width is only about 1.3m.
Commenting on the reason why NICT designed the system in this way, it said, "Unless three or more images are arranged between the right and left eyes (which are about 7.5cm away from each other), it is not possible to realize smooth motion parallax." When the density of images is low, the same image enters both the right and left eyes when the viewer moves in the horizontal direction, making 3D images unnatural.
For the future, NICT is planning to expand the angle range and the viewable width by drastically increasing the number of projectors.
"Within 2011, we will triple the angle range and expand the viewable width to about 4m, which is almost the same as the width of the screen," NICT said. "Then, there will be almost no limit to the viewpoint."
The total pixel count will be more than one billion, it said.
Because of those improvements, the development of the screen seemed to have entered a phase where commercialization is considered. NICT said that it is receiving an increasing number of inquiries from organizations in and outside Japan, especially from overseas automakers.