photochromoscope
/ˌfəʊtə(ʊ)ˈkrəʊməskəʊp/noun
A device for viewing a set of three monochrome photographs stereoscopically through red, green, and blue filters so that they are seen as a single appropriately coloured image. Compare kromskop. Now historical.
Origin
Late 19th century (in an earlier sense). From photo- + chromo- + -scope.