Orotrons of frequency range 140–300 GHz

Experimental investigation of two embodiments of orotrons in frequency range 140GHz–300GHz was carried out. The electrodynamic system is designed on the basis of an open resonator, including one plane mirror where double-row periodic structure (DRPS) is installed and focusing mirrors of two types — spherocylinder and multifocal spherical mirror. The longitudinal axis of spherocylinder is parallel to the axis of symmetry of DRPS. The multifocal mirror is formed by some (3 or 4) crossed spherical surfaces with general plane of symmetry along the interaction space of the device. The comparative analysis of output parameters of orotrons with multifocal and spherocylindrical mirrors shows that the correct choice of their geometries efficiently increases interaction length and correspondingly reduces start current value in the orotron.