film leader indicator
/ˈfɪlm ˈliːdəɹ ˈɪndɪkˌeɪtə/
n
English · film leader indicator中文 · 胶卷头指示器Español · indicador de inicio de la películaFrançais · témoin de l’amorce du film
意味：Indicator showing whether the film leader (end of the film extending outside the cartridge) is properly inserted into the take-up spool.