有一个开普勒望远镜,物镜焦距为300mm,目镜焦距为30mm,中间加入一个由两块透镜组成的-1 x 转像系统,透镜焦距分别为200mm和300mm,间隔为250mm。 该系统的物方视场角2ω=4°,在物镜的像面上有一场镜,在目镜的物平面上有一分划板,物镜的口径为60mm,是系统的入瞳。设所有的透镜均是薄透镜,求:
【简答题】Kevin is a 12?year?old boy. He from New York. He is in Class 5, Grade 7. Mr Zhang is his class teacher. He is a good teacher. All the students of class like him very much. There are forty in the class...
【简答题】完形填空。 Look 1 the woman in a yellow coat. 2 is my teacher. She teaches 3 English. She is a good teacher. Her 4 is Wang Hong. Her bike is red. 5 under the tree. Her brother, Wang Dong 6 in a black coat....