3D projection has been available in various forms for a very long time. The first mainstream 3D films made their debut during the 1950s. People at the time were convinced that 3D was the Future of Cinema. Films like Bwana Devil, Man in the Dark, House of Wax, and It Came from Outer Space thrilled audiences with this new technology. Despite a strong push, 3D didn't stick. The few 3D theaters that existed had a hard time with the expensive, complex equipment. Small mistakes could send the two-projector system out of synchronization and destroy the effect. Audiences were dissatisfied with the lackluster image quality and poor viewing conditions. For a number of years, 3D lay dormant.
3D made a brief comeback in the 1980s. This time the technology was a little better--theaters were able to show 3D with a single projector instead of two. This greatly reduced the occurrence of synchronization errors though an improper repair splice by a projectionist could still cause the movie to lose synch. This period also saw the birth of IMAX 3D. For a few years, 3D enjoyed a healthy resurgence and people were again convinced that it was here to stay. But with content like Jaws 3-D, Friday the 13th Part 3, and Amityville 3-D, audiences soon tired of the gimmick and the craze faded away.
Now, 3D has made yet another comeback with films such as The Polar Express, Coraline, Monsters vs. Aliens, and (of course) Avatar. This time around, there are several key differences which indicate that 3D might be here for good. With the advent of digital cinema, synchronization and timing issues have been eliminated. Decreases in the cost and complexity of cinema projection equipment have made it possible for 3D systems to be installed in many more theaters. And filmmakers are learning how to work with 3D, leaving behind the gimmicky effects of the previous generations in favor of more immersive, integral applications of depth.
Perhaps most importantly, it is now much easier to bring the 3D experience into the home. With active LCD shutter glasses, a compatible display, and a powerful enough computer, we are at the point where movies and video gaming can be seen in high quality 3D that closely approximates the commercial theater experience. Blu-ray players are on the way which will deliver full 1080p movies in 3D to TVs and projectors capable of diplaying them.
3D has been around a long time and has fallen flat before, so an assertion like "3D is here to stay" is not to be made without some consideration. With the recent technological advances in both cinema and home 3D projection, however, the stakes are higher than ever.
What is 3D?
In a nutshell, 3D technologies use two overlapping images to increase the viewer's perception of depth. One image is for the right eye, the other for the left eye. Content is filmed using a specialty camera system with two lenses which are separated horizontally, much in the way your eyes see two slightly different images. This creates the impression of depth, making the image appear to extend farther back from the surface of the screen and in some cases to pop off the screen towards the viewer.
There are several competing implementations of 3D technology, but they all accomplish the same objective: they show a different image to each eye. This is achieved through the use of different types of glasses which selectively show different parts of the picture to your left and right eyes. What differs among the methods in use is the way the two images are created and the way the glasses function to separate the images.