Front projected glasses-free 3D technology developed in Korea

22 August 2012

Researchers in South Korea say that they are well on the way to creating a front projected, glasses-free 3D experience with a single projector thanks to a new technique.

The team from Seoul National University has published its findings in the journal Optics Express.

Flat panel manufacturers attempting to make a glasses-free 3D experience have used a technique involving what is known as a "parallax barrier". This involves placing a barrier in front of the image source which has slats in it similar to those of Venetian blind.

These slats are angled so that light from one set of the TV screen's pixels shines through and is directed to one of the viewer's eye, and light from another set is shown to the other eye - with no overlap.

But this only provides a 3D-effect if the watcher is sitting in a specific spot, or one of several sweet spots depending on the system.

The South Korean team mimicked this technique, but adapted it to support a much wider variety of viewing angles.

They did this by creating the slat-effect using polarisers - similar to those used in the lenses of 3D cinema glasses.

Their screen was also covered with a special coating, and this combined with their adapted barrier produced many pairs of images - enough in theory to accommodate a cinema audience.

What appears to have happened is that the glasses have effectively be removed from the audience and placed on the projector. A much better place in our opinion, there is however no information on the effect of the filter on image brightness, which is another complaint often levelled at polarising glasses.

The lead scientist Byoungho Lee, professor at Seoul National University, said that more research was necessary, but the technology "might constitute a simple, compact, and cost-effective approach to producing widely available 3D cinema, while also eliminating the need for wearing polarising glasses".