Stereokuvat

Stereokuvat, also known as stereograms or stereoscopic images, are visual illusions that display a three-dimensional object or scene from a two-dimensional image. They work by presenting two slightly different images of the same subject, one for each eye, and relying on the brain's ability to merge these disparate images into a single, cohesive three-dimensional perception. This process mimics the way our natural vision perceives depth, as our eyes are spaced apart and therefore see slightly different perspectives of the world.

There are several common types of stereokuvat. Autostereograms are perhaps the most well-known, often found in books or online, where a repeating pattern of dots or lines contains the hidden 3D image. To view these, one must look at the image without focusing on it directly, allowing the eyes to relax and converge or diverge in a specific way to reveal the depth. Another type involves physical stereoscopes, devices that hold two separate photographs or slides, one for each eye, and use lenses to align the images and create the illusion of depth. These have been popular for entertainment and educational purposes for over a century. The principle behind all stereokuvat is to provide the brain with the binocular disparity information it needs to construct a sense of three-dimensionality.