AbstractsEngineering

"The diffraction theory for the transmission of electromagnetic fields through a grid in a dielectric is derived and experimentally checked in the visible wavelength region. In the far infrared, an approximate mathematical representation is found to describe the grids in dielectrics. The empirical equations in the far infrared are combined with the electrical circuit-transmission line analog for inductive grids. Detailed structure of the transmittance versus wave number curves are presented. Then the theory of multielement grid filters is derived and compared with experiment. The properties of the filters can be predicted from a knowledge of the characteristics of the individual grids. The filters are treated as asymmetric Fabry-Perot interferometers coupled and in series. Room temperature and low temperature data for combination filters are presented. The fabrication techniques and materials are described for filters in a dielectric" – Abstract, page ii.