Abstract
Asymptotic ray theory (ART) or Geometrical optics approximation shows singularity in the focal region of focusing systems. Maslov's method is a technique which overcomes the defect of asymptotic ray theory (ART). In this research work, electromagnetic field expressions for a paraboloidal mirror are derived in which incident electromagnetic field is considered to be oblique. In this work polarization of the incidence wave are studied under two cases, when the field is parallel and perpendicular to the assumed meridional plane of incidence. The procedure used to calculate the electromagnetic field in the focal region of paraboloidal mirror is Maslov's method. The numerical integration is performed for the integrals obtained by this technique in order to get information about intensity of field in focal region.