Sawyers- és GAF View-Master nézőkék

Inventor William B. Gruber introduced his 3D stereoscope at the New York World's Fair in 1939. The early reels were made out of 16 mm Kodachrome films, which can be rolled with a simple button, located on the side of the viewer. During World War II it was used for military education. It became popular when the production of reels for children about tales and comics started (other themes also remai…