The Mul­ti­col­ore is sup­plied with colour fil­ters to alter the tint of glass stere­oviews dur­ing view­ing. The black front panel—with the focus knob posi­tioned between the lenses—is iden­ti­cal to that of Lucien Bize’s Min­imus. This con­struc­tion appears to be a dis­tinc­tive fea­ture of Bize’s stereoscopes.
An appar­ent­ly unre­lat­ed patent by Jules Marinier from 1864 also describes a stere­o­scope design incor­po­rat­ing colour fil­ters. The title of the patent includes the term multicolore.
(from: Com­pendi­um of Stereoscopes)