The actor became internationally known after starring in that blockbuster film.

known 是动词 know 的过去分词形式，know 的意思是"知道、了解"。 在这里 known 作为形容词使用，表示"被知晓的、知名的"，指某人或某事被广泛认识或了解的状态。internationally known 表示"国际知名的"。