A microfiche is a flat sheet — about the size of an index card — that holds many tiny photographs of pages. You cannot read it with your eyes. You slide it into a special reader that shines light through it and throws a big picture onto a screen. Libraries and archives used these for old newspapers, theses, and records, because one sheet can hold dozens or even hundreds of pages and does not take much shelf space. Though actually, people say microfiche and microfilm as if they were the same. Film is often a long roll you wind; a fiche is a single flat sheet (the French word fiche is a slip or card). You still meet both in older libraries, though computers have taken most of this work. It can be a noun (a microfiche) and, more rarely, a verb (to microfiche something = to copy it onto these sheets). It feels a bit old-fashioned and official.

縮影單片（圖書館用語；對照捲起來的是「縮影捲片」。中國大陸常說「縮微平片」）