Optimization of Beam Focusing into the Stark's Cell for MM-Wave Spectroscopy

In case of adding and using of dielectric lens in front of horn antenna, a plane wave is created at the short distance behind the lens with the Gaussian amplitude distribution, which is therefore focused into the very narrow beam. This energy focusing is used in the microwave, millimetre-wave and terahertz spectroscopies in order to reach the optimal coupling of energy into the measuring cuvette. This paper presents an analysis of the power distribution behind dielectric lens and optimization of the beam focusing by double sided dielectric lens into the Stark's cell as a particular part of spectroscopic measuring equipment.