A high-drop air-hole-type photonic crystal ring resonator(PCRR)was proposed based on twodimensional square lattice configuration.The single mode operation can be realized by compressing the width of bus waveguide.The impact of number of rows of holes on the propagating field intensity distribution was also analyzed.The physical parameters,such as dropping wavelength,dropping efficiency and spectral quality factor(Q)affected by changing the localized refractive index of inner ring and coupling strength betwe...