Prototype system paves way for huge, glasses-free 3D displays
Using red/blue filters (anaglyph), polarized (passive) or LED shutter (active) glasses are relatively simple ways of creating a 3D effect. Creating 3D pictures without viewers having to don any form of eyewear is a little trickier and is made even more so if you want really big 3D effects for a sports stadium or a billboard. To help address this, Austrian scientists working at the Vienna University of Technology (TU Vienna) and the company TriLite Technologies have developed a new kind of display just for this purpose that sends beams of light directly to the viewers’ eyes via a laser and a sophisticated mirror system.
Every 3D-Pixel (or "Trixel", as the team calls them) used by the prototype system consists of lasers and a movable mirror to send light beams in different directions, which the creators claim produces angular resolution so fine that the left eye is presented a different picture than the right one, thus creating a 3D effect.
"The mirror directs the laser beams across the field of vision, from left to right," says Professor Ulrich Schmid of TU Vienna. "During that movement the laser intensity is modulated so that different laser flashes are sent into different directions.'
Unlike current large-scale 3D projection systems, such as those used at the cinema where only two different pictures are projected, one for each eye, the new system can project hundreds of pictures at a time. The result of this is that a view of the scene may be made from different sides, just like the way real objects and scenes are observed. This is achieved via a new video format that has been developed by the researchers.
"Today’s 3D cinema movies can be converted into our 3D format, but we expect that new footage will be created especially for our displays – perhaps with a much larger number of cameras", said Franz Fiedler, CTO of TriLite Technologies.
According to the research team, compared to a movie screen, the display is also very vivid and can be easily used outdoors, even in full sunlight. As a result, the new technology lends itself to applications such as 3D electronic billboards that could display different ads at the same time, dependent upon the angle of the viewer.
"Maybe someone wants to appeal specifically to the customers leaving the shop across the street, and a different ad is shown to the people waiting at the bus stop," says Ferdinand Saint-Julien, CEO of TriLite Technologies.
On the downside, the current prototype only has a resolution of five pixels by three and, like the lenticular lens system used in the Nintendo 3DS and some prototype TVs, which split the image for a 3D effect without the user having to wear glasses, the viewer must be positioned at a certain distance from the screen for the effect to work. If the distance is too great, the same image is seen by both eyes at once and the effect is lost. However, according to the creators, the range in which the 3D effect can be experienced can be tuned according to the local requirements.
"We are creating a second prototype, which will display color pictures with a higher resolution," says Jörg Reitterer of TriLite Technologies and PhD-student in the team of Professor Schmid. "But the crucial point is that the individual laser pixels work. Scaling it up to a display with many pixels is not a problem."
From first design to working prototype took three years, and the technology behind the system has now been patented. The researchers are aiming for a commercial launch of the technology in 2016.
The research behind the prototype was published in the journal Optics Express.
Source: Vienna University of Technology