3D has been around for a long time. It was first used in the theaters starting in the 1950s. 3D technology has increased greatly since that time but many still use the same process they did back then. In this article we will look at the three main processes of creating 3D images for films, television and video games.
Passive Systems
Passive systems, or filtered lenses are best known as those old blue and red glasses movie-goers wore while they were at the theatre starting all the way back in the 50s. Surprisingly, they are still used today, however, they are generally not the old-fashioned blue and red that they once were. This 3D systems works by showing your eyes 3 different images. There is an image that is shown to your left eye, an image that is shown to your right eye and an image that is shown to both. The image that is shown to both helps to focus your eyes, a place from which the 3D effect can pop out from. It is also known as the “normal plane”. The biggest problem with the blue and red glasses is our color perception. Our brains have a hard time sorting broken-up colors out, so many people are left finding it hard to enjoy their 3D experience. The newest type of passive system or filtered lens uses polarization. One of the pros with polarization, over the old color glasses, is that you can tilt your head and it will not affect the image. However, with polarization you do not get the same brightness.
Active Systems
Active systems involve showing media at a high frame rate and similarly to the passive systems glasses are worn to help create the 3D image. These glasses are made up of transparent LCD lenses. In the active systems 3D process one eye is quickly shown the image while the other is shown a black screen then they are switched. This happens back and forth very quickly, creating a 3D image. Most television companies working in 3D are currently using this technology. There are a number of problems linked to this type of 3D system. For one, it is known to cause seizures. Secondly, the glasses require batteries, which can end up being costly (the glasses themselves can already cost you up to $100 each). Thirdly, how you are positioned or how you tilt your head can affect the quality. And finally, as the technology is constantly improving, it can be costly to keep up with the changes.
Parallax Barrier Systems
The parallax barrier systems uses a sawtooth prism that sends light (image) in varying directions. So, part of the light is shone into your left eye while the other is shone into your right creating a 3D effect. This system has been around for a while now. There are a number of ways that parallax barrier systems can be created but the most popular way used today is done by putting a series of lines into the display. These lines are placed exactly so that half the pixels are picked up by your right eye and the other half by your left.