Stereoscopy (noun, “Stair-ee-AH-skuh-pee”)
Stereoscopy is a method to trick the mind into perceiving flat photographs as three-dimensional scenes. Right here’s the way it works. Every eye is proven an image of a flat, or two-dimensional, scene. The 2 photos are virtually similar however present the scene from barely completely different angles. When viewing that pair of 2-D photos collectively, the mind interprets them as a 3-D scene.
This mimics what the mind does in the true, 3-D world we stay in. In on a regular basis life, every of your eyes can understand solely a flat picture of what’s in entrance of you. And since your eyes are separated by a small distance, they every see the world from barely completely different angles. (To see this distinction, shut one eye after which the opposite. Watch how the objects in entrance of you seem to shift a tiny bit.)
The mind combines the visible enter from every eye. Within the course of, the mind makes use of the slight variations between these two 2-D photographs to work out the distances to numerous objects throughout the discipline of view. (Say, as an illustration, you’re a pencil sitting in your desk. Your eyes get two barely completely different 2-D views of that pencil. By evaluating these two flat photographs, your mind can estimate how far-off the pencil is.) That is known as depth notion. And it really works whether or not your eyes are taking in two barely completely different views of the true, 3-D world — or two variations of a 2-D scene displayed on a display.
This impact is behind a lot of in the present day’s immersive tech. Digital actuality headsets present barely completely different photographs to every eye to make on-screen photographs really feel actual. Stereoscopy has additionally been used to make 3-D motion pictures. In these movies, right-eye and left-eye photographs are each displayed on display. Particular glasses assist present the proper picture to every eye. Previous-school 3-D glasses did this by letting every eye see solely particular colours of sunshine. Extra subtle glasses now present every eye solely gentle waves that wiggle at particular angles. Both method, the mind can assemble the 2-D view via every lens into a picture that leaps off the display.
In a sentence
Stereoscopy methods the mind into pondering the flat photographs displayed on digital actuality headsets are 3-D scenes.