Shark Night 3D, which chronicles the misfortunes of college aged kids on a lake house, surrounded by sharks, is the latest movie to hit theaters, which relies on 3D to sell tickets. 3D movies have come a long way since red-blue glasses, which disappeared in 2004, and have experienced resurgence in popularity following James Cameron’s Avatar. RealD 3D is the latest 3D film technology that is able to capture two projected images onto a custom screen and combine them to form a single 3D viewing experience, which stays the same from many angles.
Hold up your finger in front of you and close one eye. Now close the other eye and open up the eye you just had closed. You’ll notice that each of your eyes has a slightly different perspective of the world. The closer an item is to your eyes, the bigger this effect. When both of your eyes are opened, your brain combines the two perspectives to create the illusion of depth.
Two projected images on a screen and 3D glasses aim to do the same exact thing. Each one of your eyes gets a slightly different perspective when wearing 3D glasses, creating the appearance of depth, something which your brain does naturally. Even though technology cannot compete with the processing power of the brain, 3D viewing has progressed significantly in recent years…
Remember those red and blue glasses that you used to wear? The screen was projected with film of 2 colors: red and blue, each of which had an image that was slightly offset from the other. The glasses you wore combined the red and blue images into one, giving you an illusion of a 3D image. This “anaglyph” technique, as you may remember, lead to one image bleeding onto the other. It also distorted colors, particularly ones, which had a shade of red or blue. Needless to say, the overall 3D experience was unimpressive.
Those throw away glasses have since been replaced with polarized glasses, which use the same concept, but in a different way. Light can be given different orientations when projected onto the screen, one vertical projection, and one horizontal projection. Polarized glasses have filters, which make one of your eyes get the vertical and another one of your eyes get the horizontal. To make sure that the 3D effect doesn’t dissipate when you move your head around, each of the 2 projected orientations are rotated in opposite directions. Because the filters on the polarized glasses are a neutral gray color and are very good at filtering the different orientations, there is no color distortion or ghost images.
Linear polarizing projection has been around since 1936. However, high definition video and computer animation have fueled interest in the technology, which now allows for life like 3D viewing and an audience, which is willing to pay a premium to have movies such as Shark Night 3D and Dolphin Tale 3D seen with current 3D technology.
