slide frame
small (image) frame that includes the slide and thus allows the introduction of the film excerpt into the slide projector or slide viewer
en-GB/ˈslaɪd ˈfɹeɪm/
en-US/ˈslaɪd ˈfɹeɪm/
small (image) frame that includes the slide and thus allows the introduction of the film excerpt into the slide projector or slide viewer