Fanfold stereoscope

Also known as: Leporello stereoscope

A fanfold is a continuous sequence of connected paper cards folded in alternating directions to form a compact zigzag/harmonica stack. Each section remains attached to the next, allowing the material to be extended as a continuous strip and refolded into a compact arrangement after use. The format provides ordered sequential access while minimising storage space.

The fanfold concept was applied in some multi-view stereoscope designs in which a continuous series of stereoviews could be advanced through the viewer in sequence. This provided an alternative to stereoscopes based on chain-based mechanisms.