Part 1 of Essay
Single Image Random Dot (SIRDS) are not only a lot of fun, but they demonstrate many of the properties of stereopsis. "Stereopsis" means that each eye sees a slightly different image, also known as three dimensional or 3D. Stereopsis is essential for our perception of depth. Leonardo da Vinci demonstrated in his writings ....

Part 2 of Essay
.... circle and the selected dots are the dots that fall within the blue circle. (fig. 2). Next, he created a new rectangle identical to the original rectangle, except that the dots within the small shape have been shifted to the left. (fig. 3). When the two rectangles are viewed together as a stereo pair, the image of the circle appears to float above the background. (fig. 4). In 1979 Christopher Tyler discovered that the offset scheme could be applied to a single image. This was ....