3D is a phenomenon of visually perceiving three dimensions on a two dimensional plane. It was first developed by Sir Charles Wheatstone in 1838. The “technology” entailed the overlay of two identical images that are slightly off register, creating the illusion of a third dimension. The effect, called stereopsis, was popularized by the invention of hand-held viewers which took advantage of stereopsis in the early 20th century. The hand held device quickly became a popular in parlors throughout the world. The public marveled at this hi-tech wonder. Those of us who grew up In the 50’s and 60’s recall spending hours gazing through the old Viewmaster. The ubiquitous viewer captured 3D images on a disk that rotated as the viewer clicked to the next image. The device resembled a set of binoculars that viewed pictures of far off lands and popular movie stills, except in true 3D. Many remember viewing the images as the 3D effect brought them to life, creating a true-to-life experience that could never be duplicated on the printed page or TV screen.
Today, experiencing video in 3D is a common experience. The technology has employed the principle of stereopsis in movies with an entirely new 3D experience. Although the technology has evolved, it is still based on the principles established by Wheatstone over 175 years ago.
Today’s 3D technology still employs stereoscopy that tricks the brain into “seeing” what it perceives as a third dimension. This is accomplished much like the Viewmaster created an illusion of dimensionality. It is based on the knowledge that each eye perceives a slightly different view of the world. This can be demonstrated holding a pencil tip in front of your eyes. First, close your right eye and observe the positioning of the pencil tip. Then close your left eye and look at the pencil tip. You’ll observe that the left eye perceives that the pencil tip has shifted to the right. It is that simple geometric formula that applies to all 3D, regardless of the technology in use.