The polarization-preserving property of photonic crystals (PhCs) is combined to the superior extraction efficiency of embedded PhCs to enhance polarized light emission in m-plane GaN light-emitting diodes. As guided modes in m-plane GaN are mostly polarized along the a-direction (Ea), their efficient extraction is achieved by one-dimensional embedded PhCs also aligned to the a-direction. A better diffraction efficiency is obtained by air-gap PhCs which required the growth of high quality, defect-free, m-plane GaN coalesced over the embedded air-grooves. (C) 2011 American Institute of Physics. [doi:10.1063/1.3602319]