In 1838, scientist Sir Charles Wheatstone outlined the concept of “stereopsis” or “binocular vision” – where the brain combines two images (one from each eye) to make a single 3D image. This led to the development of the first stereoscopes, devices that took a pair of images and turned them into a 3D image with the illusion of depth. Stereoscopic displays are used in today’s VR systems to bring a sense of depth to digital images – thereby enhancing the feeling of immersion.