【简答题】There are many TV programs on Chinese cooking. However, few programs are like A Bite of China (舌尖上中国). It tries to bring something new by introducing more cultural features (特征) of dishes, such as eat...
【简答题】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°,在物镜的像方焦面上有一场镜,在目镜的物方焦平面上有一分划板,物镜的通光口径为60mm,是系统的入瞳。设所有的透镜均是薄透镜,求: