The first word is "day", the second word is "day", "Ming", the third word is "crystal", the word is four words on the word combination, the latter three are the world "".

A fully vectorial effective index method is proposed and used to study the dispersion properties of photonic crystal fibers in combination with the concept of normalized dispersion.

Beam coherent combination of two photonic crystal fiber (PCF) lasers is experimentally studied by using self-imaging resonator technique, and phase-locking of the two PCF lasers is achieved.