THE
Visionaries
3D Glasses
3D Glasses
Background
In the mid-19th century, Charles Wheatstone discovered that the 3- dimensional effect can be formed simply by viewing a pair of images side-by-side where these images are slightly separated.
In the late 19th and early 20th century, the stereoscope was invented. It used lenses that merged the two distinct images into one, giving the 3D effect without straining the eyes.
Traditional plastic glasses with red and blue lenses when used with special photographs called anaglyph images, create the illusion of depth. In the past, anaglyph images were taken using two slightly separated cameras, one with a red filter and one with a blue filter. Now, the filtering is being done afterwards with a processing program like Adobe Photoshop.
However, polarized 3D glasses allow for more accurate colour viewing than anaglyph images.
How does it work?
To understand what polarization is, imagine you are holding to a hose. If you shake the hose up and down, you will generate vertical 'waves' that also move up and down hence creating a vertically polarized wave. On the other hand, shaking the hose left to right will generate horizontally polarized waves. Light is a wave made up of electric and magnetic fields that vary in time and it can be made to be vertically or horizontally polarized.
One of the lenses on the 3D glasses allows only vertically polarized light to pass through, while the other allows only horizontally polarized light. Two projectors show slightly different images, using light polarized in one or the other direction. In this way, each eye sees a different image, just like you would if you were viewing the scene in real life.
The working of 3D-glasses is based on the use of a technique, stereoscopy. Stereoscopy is a technique that creates an illusion of depth by projecting a separate image to each eye.
Applications
Application to Entertainment/ Media Industry
The polarized lens system is used at Disneyworld, Universal Studios and in IMAX 3D theatres. Two synchronised projectors project two images on the screen. These images are projected in two different orientations, typically at 45 and 135 degrees relative to the horizon. The polarizer films in the 3D-glasses filtered the images, allowing only one of the images to enter each eye. The perspective difference between objects seen through the left and right eyes create the illusion of depth, also known as the 3D effect. Some of the popular movies release with a 3D were Kung Fu Panda 2, Toy Story 3 and Avatar.
