Compact  on InP single ring resonators incorporating  multimode interference (MMI) turning mirror couplers with cross coupling factor of 0.15 have been demonstrated. Two MMI turning mirror couplers of 128mm in length are used in the single ring resonators, which correspond to free spectral ranges of 83GHz. A contrast of 3dB for the drop port and full-width at half-maximum (FWHM) of 0.24nm for the drop port have been achieved  in this single ring resonator. From the experimental value  of 21dB, the experiment coupling factor agrees with the simulation.