Fibre optic interconnecting devices and passive components - basic test and measurement procedures - part 3 - 25 : examinations and measurements - concentricity of the ferrules and ferrules with fibre installed 光纤互连设备和无源元件.基本试验和测量程序.第3部分第25节:检验和测量.装配有光纤的金属加固环间的同心度