The stereoscope was invented in the 19th century as a novel way to lend perspective to photographs.Two identical photos taken from slightly offset lenses and then placed side by side in the stereoscope gave the viewer a three-dimensional image of a scene . Similarly,Nymbus2000 use this method to convey a three-dimensional image by improve a visualability and more vivid as a sense of reality  With adjusted span make more dimensional image as you never seem before. With a big prism lens can fixed your both eyes stay on your mornal eyed-view without make any stress and no need experienced like crossed-eyed view or parralelled-eyed view.