Dolby 3D vs RealD
The variety of 3D technology used in cinemas and their respective glasses can be confusing. With names thrown around like RealD, Stereoscopy, Anaglyph, Liquid Crystal Shutter, Polarized lenses and Dolby 3D, it's easy to be left wondering how 3D technology works and which 3D glasses are the best.
That may have been the situation a few years ago but as with most new technology, a large number of prototypes eventually boil down to just one or two mainstream success stories. HD is fast winning the home cinema race and Blu-ray has already trumped its nearest competitor, the now extinct HD-DVD. The same will surely happen with 3D glasses.
In terms of these glasses, the frontrunners have emerged as Infinitec super-anaglyph glasses for use in Dolby 3D cinemas, and circularly-polarized stereoscopic glasses for RealD cinemas. Both are 3D glasses the viewer must wear to experience a 3D movie, but there are subtle differences between the two, which we'll take a look at.
Infinitec GmbH is a German, Zurich-based company specialising in information technology software. Dolby licensed them to create the 3D glasses that would be used exclusively in Dolby 3D cinemas. Unlike RealD's need for a special silver screen to be installed, Infinitec glasses can work on normal cinema screens with projectors that show 3D movies as easily as 2D movies. All that's required is a rotating filter wheel to place between the lamp and picture element of the projector, a filter controller (such as the DFC100) to synchronize the images and, of course, the glasses themselves.Since RealD requires a silver screen to keep the light polarized and reflect it back as much as possible to counter polarization loss, you'd need a new, dedicated screen, whereas Dolby 3D can project 2D or 3D films onto existing screens just by adding or removing the filter wheel, making them far cheaper and easier to implement.
Infinitec glasses may be more expensive to make than the typical polarised glasses used in RealD cinemas (which are used once and then thrown away), but Infinitecs are lightweight and can be washed after each use, making them better for the environment and easier to split the cost since they can be used around a hundred times before needing to be replaced.