Watching Hollywood movies in 3D theaters makes use of polarized 3D glasses.
Watching movies in 3D format can be done in a variety of ways. Many 3D systems require the use of 3D glasses so that the person can properly view footage in 3D. Each kind of 3D glasses uses a different technology to separate the images seen by the left and right eyes. In doing so, the brain is able to process these “left” and “right” images and render them as three-dimensional depth.
Anaglyph 3D Glasses
The oldest 3D technology uses the anaglyph 3D glasses, which are still popular because they are the cheapest and most accessible type of 3D technology available to the general public. This system is easily recognizable with its red-green, red-blue, blue-amber, green-magenta or red-cyan lenses. Anaglyph 3D uses color filters to separate the left and right images into slightly different footage distinct for each eye.
While it’s not as technically effective as newer 3D technologies, anaglyph 3D is so far the only type of 3D system that makes it possible for anyone to upload 3D movies to the Internet and still provide 3D effect to anyone who views it using a cheap or even a do-it-yourself pair of anaglyph 3D glasses.
Polarized 3D Glasses
Polarized 3D glasses are popularly used in 3D movie theaters and theme parks. This system is the common method used in Real-D and IMAX theaters as it offers a much better image quality. It allows the viewer to see colors and details more accurately because it utilizes different light frequencies to separate images without sacrificing picture quality and color.
This system generally works by restricting the amount of light entering each eye through polarizing filters found in the lenses. This makes it work similar to anaglyph 3D, except that it uses light waves to make the differences on the left and right images instead of using color. Therefore, the 3D viewing experience features a more visceral and life-like quality to the images.
3D Shutter Glasses
The 3D shutter glass system is a technology more popularly used in 3D TVs. This requires the TV screen to display two alternating images for each eye. This is done in rapid succession using a special type of glasses that block the view of one eye, then the other eye.
Because using such an active pair of 3D shutter glasses makes the left and right images to flicker on and off at very high-speeds, the glasses actually communicate wirelessly with the TV’s LCD display to make sure everything is synchronized. The interaction enables the viewer to see different images for each eye through the variation of light filters offered by each lens. The wireless communication is typically controlled using Infrared or Bluetooth technology.
Pulfrich 3D Glasses
Pulfrich 3D glasses create a 3D effect through one completely transparent lens and another heavily tinted lens. The image shown through the dark lens reaches the brain on a slightly later time compared to the one passing through the clear lens. This follows the concept that low light levels respond slower in terms of sending visual information from the eye to the brain.
The relative delay in image perception for this system provides a variation between the images seen by the left eye and the right eye. While it works similar to anaglyph 3D glasses, this system doesn’t alter the images’ colors.