We report the creation of a double-feedback optical element based on a Fabry-Perot cavity filled with a planar aligned cholesteric liquid crystal mixture. The reflection band of the liquid crystal is in the near infra-red region. The polarization and spectral properties of this element are characterized experimentally and simulated theoretically. Preliminary experimental results are obtained for the transmission's dependence upon the orientation of the linear polarisation plane and the polarization state of the incident probe beam, with a wavelength out of resonance. The corresponding theoretical simulation results are in qualitative agreement with the experimental results.