Dolby 3D glasses - how it works
For an occasional 3D movie viewer, the idea of different technologies that go into making the movie look so realistic may not be that interesting, but for the regulars, quality differences are quite obvious. There are several companies in the world right now that produce projectors, 3D glasses and whole 3D systems for commercial use as well as at-home experiences, with Dolby leading their way for many years now. How does their system and 3D glasses compare to the others and how exactly do the glasses work?
All the modern laser projectors operate on the idea of using red, green and blue as the colour scheme that can create every colour there is and thus provide an excellent depth and quality of the image. Although the systems are all similar as far as the laser projectors go, it’s the minute details that make the most difference when it comes to the quality and depth of the 3D image. Dolby based their system on different colour wavelengths – a special, alternate colour wheel is placed in the projector, allowing it to produce the same RGB colour scheme with different wavelength for each eye. As a result, the 3D image is created with each lens of the 3D glasses picking up a different light frequency. The idea is now known as wavelength multiplex visualisation and as far as cinematic world goes, it is the biggest project that Dolby released so far. They are also the only ones that use it so well. After all, why change something good? But how does it go with the glasses?
In order to have glasses work with the Dolby 3D system, they had to come up with dichroic 3D glasses that were able to pick up different wavelengths of RGB light with each lens, allowing the viewer to see the displayed picture in 3D. How it works is simple – one lens is picking up one set of wavelengths, while the other one is picking up the other one and blocking the first one out. Doing the projection this way, there’s no need for projectors to display one image after the other – they can display the left and right stereoscopic picture simultaneously, which means no loses on the quality or dynamic part of the movie. Not every pair of 3D glasses can do such thing – with all the technologies and variations within 3D display, it’s almost impossible to make one pair that serves all purposes.
Original photo: Visit Dolby.com