High flux porous hollow fiber membranes are produced from perfluorinated thermoplastic polymers by extruding a heated solution of the polymer having a lower critical solution temperature directly into a cooling bath to form the porous membrane by liquid-liquid phase separation. Measures for improving the outcoupling of the light generated in the layer sequence are provided on both the first and the second main emission surface. Extending through the rear face and between the heel area and toe area is a cavity. By analyzing the distribution, one can adjust the distance and the incidence angle between the reflection mirror and the reference beam. A coaxial feed is connected at a predetermined location near the center of a patch, having a narrower width, in order to match the input impedance of the antenna to the coaxial feed.