3557541 Japanese girls using a stereoscope viewer with stereographic cards, 1899 (photo) by Japanese School, (19th century); Private Collection; (add.info.: Stereoscopy is a technique for creating or enhancing the illusion of depth in an image by means of stereopsis for binocular vision. The word stereoscopy derives from Greek ??庰?庰?? (stereos), meaning \'firm, solid\', and ?庥怷?峟? (skope?), meaning \'to look, to see\'. Any stereoscopic image is called a stereogram. Originally, stereogram referred to a pair of stereo images which could be viewed using a stereoscope; ); Prismatic Pictures ; Japanese, out of copyright.