Fabry-Perot cavities are generally used in cavity QED. Due to technical restraints it is prudent to evaluate the ability to create open micro cavities in the weakly coupled regime. We have focussed...Show moreFabry-Perot cavities are generally used in cavity QED. Due to technical restraints it is prudent to evaluate the ability to create open micro cavities in the weakly coupled regime. We have focussed on building the foundation for the weakly coupled cavity by charactarizing a macroscopic cavity in detail. We analyse the cavity effects, for the fundamental and higher order modes. Using the primary mode of a plane-curved mirror cavity we found the Free Spectral Range in multiple ways, and looking at transmission spectra as a function of wavelenght we found a spectrum of transmission peaks with a predictable mode ordering. Thus the cavity was found to be consistent with theory. The system has been improved upon by presenting an extensive model for modematching. The model is capable of determining the coupling efficiency after introducing a lens with any focal length and possible position. With the model we were able to find a setup configurations with near unity coupling efficiency to the fundamental mode of the cavity.Show less