A Method to Improve Angle-Tuned Filter´ Polarization Characteristics

Beginning with the analysis of phase relationship and by use of the characteristic matrix expression of films, this paper deduce two implicit function expressions of moderate refractive index of spacer and central wavelength of P-polarization & S-polarization .Therefore the value of moderate refractive index and corresponding central wavelength can be quickly and accurately obtained. Simulation calculations of concrete filter design for three cavities prove that the method is feasible. We also proves that the algorithm is highly accurate though the examples data analysis of curves with incidence angle from 0° to 30°.