抄録
Photonic crystal fiber (PCF) has an array of the air hole that surrounds the core region. PCF is classified
into two types by the difference of the principle of the optical guide mechanism. One is called index
guiding type PCF, that confines the light into the core by lower effective refractive index of the cladding
region. The other type is called PBGF (photonic band gap fiber), that has the optical guide mechanism
based on the photonic band gap effect. In this report, we discuss the properties of various types of PCF,
namely endlessly single mode (ESM) fiber, high birefringence polarization maintaining fiber, bending
insensitive hole assisted fiber and double cladding fiber with air holes. We also discuss the property of
PBGF.