What is the difference between WDM and Splitter?
WDM mainly manage wavelengths,Splitter mainly split optical power(light ratio).
WDM each output port only can through a certain wavelength,for example,CWDM each output port only can through one wavelength of 1270-1610nm,no split optical power function.
Splitter each output port through different or average optical power(light ratio) from common port,its each output port still can run wavelength from 1260-1650nm.FBT 1310/1550 or 1310/1490/1550 still can run wavelength 1260-1650nm,just over other wavelengths the insertion loss higher.