Patent illustration US Patent Office A stereoscope is used for viewing a stereographic pair of images that are placed side-by-side on a card or presented on a digital screen. A lens board has left and right apertures defining a horizontal base line. A pair of prismatic lenses are fitted into the left and right apertures, respectively. A stem or handle projects from the lens board in the plane of the lens board midway between the apertures and perpendicular to the base line. A removable opaque synthetic rubber hood is fitted onto the lens board and has eye covers of generally tubular shape.