【摘要】 ＩＵＴ－Ｔ在Ｇ．６５０建议中，模场直径定义是严格基于远场扫描测量给出的，然而实际上它与现今普遍采用的Ｐｅｔｅｒｍａｎｎ定义是完全一致的。本文从理论上推证运场扫描、可变孔径法定义的模场直径与Ｐｅｔｅｒｍａｎｎ定义的模场直径一致。更多还原

【Abstract】 In ITU-T G. 650,definition of mode-field diameter is given based on farfield scan measurment,whereas definition of mode-field diameter by far-field scan conform with daily common used Petermann’s definition substantially. In this paper,conformability of defining mode-field diameter by far-field scan and variable aperture with Petermann’s definition is derived from theorem.更多还原