What is a Stereoscope?
A stereoscope is a viewing device which allows users to create a three-dimensional image from a set of two-dimensional photographs or drawings. Original stereoscopes were popular around the turn of the 20th century, and featured a clip for holding special stereoscopic cards in place. The viewer would peer through a rudimentary binocular system, which forced each eye to see only one of the two images. By either crossing or diverging one’s eyes, a third image would eventually appear in the middle, and this image would provide the illusion of depth for as long as the viewer maintained proper concentration and focus. The secret behind the stereoscope was the relative perspective of the photographs or drawings. When both eyes are trained on the same two-dimensional picture, the viewer’s brain does not receive enough divergent information to form a binocular or three-dimensional image. The photograph will remain two-dimensional, with no sense of depth. However, if two images are taken at the
Stereoscopes, also known as stereopticons or stereo viewers, were one of America’s most popular forms of entertainment in the late 1800s and early 1900s. The first patented stereoscope was invented by Sir Charles Wheatstone in 1838. Wheatstone had experimented with simple stereoscopic drawings in 1832, several years before photography was invented. Later, the two principles were combined to form the stereoscope. A stereoscope is composed of two pictures mounted next to each other, and a set of lenses to view the pictures through. Each picture is taken from a slightly different viewpoint that corresponds closely to the spacing of the eyes. The left picture represents what the left eye would see, and likewise for the right picture. When observing the pictures through a special viewer, the pair of two-dimensional pictures merge together into a single three-dimensional photograph.
