§ 2. Summary writing: Read an excerpt from David Crystal ( English grammar in the UK: a political history (Profile, 2017) and Post your summary online before March 19th.
【简答题】请写出: 1、光纤的归一化频率V的物理含义。 2、光纤的截止波长的物理含义。 3、第一类、二类、三类Bessel函数及其变形函数。 Please write: 1. Physical meaning of normalized frequency V of optical fibers. 2. Physical meaning of cut-off wavelength of optical fi...