Video: 3D videoconferencing (Artwork courtesy of CaptinCaptin and Madi Boyd)
A technique that started life as an optical illusion to thrill Victorian Londoners could soon be adding a new dimension to videoconferencing. London-based company Musion has adapted the method that creates life-size hologram-like images for theatrical purposes to the needs of modern businesses.
In the 19th century Henry Dircks, and later John Pepper, developed an optical illusion to convince audiences they were witnessing ghostly activity. A large sheet of glass was positioned at an angle between two rooms; a target room visible to audience members and another out of their line of sight. Shining a light on a character in the hidden room creates a reflection that seems to materialise in the target room, or on the stage, as a ghostly spectre.
In this form, “Pepper’s Ghost” is still used in theme parks today. But incorporating huge sheets of glass into large attractions is problematic, says Ian O’Connell, director of Musion. His company has replaced them with the transparent polyester foils used to package microwave meals.
Using a process called biaxial orientation, the polyester is stretched in both horizontal and vertical directions during manufacture to create an incredibly strong film which is just 0.1 millimetres thick. “A large foil could be under 5000 to 7000 kilograms of tension, ” says O’Connell. This is necessary to ensure that the surface is perfectly smooth and flat to reflect the image without distorting it.
Musion is building a reputation among performance artists trying to add new elements to their stage shows. Their holographic projection technology has been used by both Madonna and virtual band Gorillaz.
The image itself comes not from hidden actors but from a digital light processing (DLP) projector tucked out of the audience’s sight. The plastic foil is hung under tension at a 45-degree angle across the front of the stage, reflecting the projector feed onto the stage to give the impression that the actors are performing on the stage (see video).
“This isn’t a hologram, it’s a virtual image, ” says O’Connell. “But it looks enough like people’s expectations of a hologram for most people to call it one.” O’Connell says the system could be used to provide more realistic videoconferencing.
However, hardware prices will have to drop some way for the technology to become a realistic option for many companies. To produce crystal clear life-size images, Musion’s system incorporates a high-definition camera that costs at least £4500 ($7500) and a professional-standard codec – hardware that compresses the data into a package small enough to be sent via the internet. These come with a hefty price tag of about £36, 000 ($60, 000).
Then there’s the DLP projector which has to be as bright as possible because only a small fraction of the signal is reflected by the thin foil and out from the stage. Musion typically uses 8000-lumen projectors that also retail for about £36, 000.
“Then there’s the telecom lines, ” says O’Connell. All videoconferencing options run on dedicated private lines that can cost up to £30, 000 ($50, 000) per month, he says.
But O’Connell’s reckons prices will drop. “The technology is there but it’s [lack of]economies of scale that are keeping the component costs high, ” he says. Within a few years the cameras and projectors could be one-tenth of their current prices, and software codecs could replace current hardware versions.
O’Connell goes so far as to suggest that Musion-enabled “entertainment suites” could one day replace televisions.