The study of three dimensional imaging and depth perception started in the sixteenth century, with Leonardo Da Vinci. Da Vinci understood that our eyes perceive images slightly different in each eye, because they see things from slightly different angles. The combination of these two angular views gives humans the ability to perceive depth.
It was not until the late nineteenth century that Joseph D’Almeida took the same principles Da Vinci had noticed centuries before and imparted them upon a device that allowed two different images to be created using two different wavelengths of light – red and blue/green. By taking photographic images at slightly different angles and combining the pictures was the foundation for stereographic and stereoscope graphics. When D’Almeida applied the light filters, a 3D effect took place; the technical term for this technique is ‘anaglyph’.
In 1894, William Friese-Greene filed for a patent and premiered the first 3D anaglyphic viewing process. This was achieved by placing two screens side by side and blending the viewer’s vision by a stereoscope headset.
In Los Angeles, California in 1920, The Power of Love is the first 3D movie screened for a commercial audience. The film was developed by Robert F Elder.
By the 1950’s, comic books and magazines took hold of the anaglyph industry. Joe Kubert and Norman Maurer created a 3D comic book starring Danger Mouse These comic books came with a pair of red/green 3D glasses that allowed the viewer to see the anaglyph images in the book.
As of today, there have been many advances in 3D glasses technology and we are not subjected to wearing the old-fashioned red and blue plastic frames any longer. There are two types of 3D viewers and they are categorized into two systems, active and passive.
The only active viewer is a shutter system, which works by presenting images to one eye while simultaneously blocking the other. These glasses are time signal controlled, which allows the liquid crystal shutter glasses to darken in an alternating pattern between one eye and the other. This pattern fluxes with the refresh rate on the screen.
Passive 3D viewers work on polarization systems, which cause two images to be superimposed and then projected onto the same screen through a series of polarizing filters. When using passive type of polarization, viewers wear low-cost eyeglasses that contain a pair of lenses that use the opposite polarization of filters as opposed to those that appear on the projection. Only light that is similar passes through the respective lens filter while the other is blocked out completely, thus only one eye sees one image at a time and the 3D effect is achieved.