opera glasses
noun [ plural ] uk/ˈɒp.ər.ə ˌɡlɑː.sɪz/ us/ˈɑː.pɚ.ə ˌɡlæs.ɪz/
观剧镜（指看戏用的小型双筒望远镜）
small binoculars that can be used in large theatres by people sitting far from the stage, so that they can see the performers more clearly
Compare: binocularsfield glasses