Abstract: A quasi-optical component for microwave radiation comprises a quasi-optical element (16a) which radiates incident microwave radiation along a major axis (19) and which has a characteristic transverse dimension (D) which is smaller than 50-times one wavelength. It is distinguished by the fact that a cooled absorption device (17) is provided which is arranged closely in front of the quasi-optical element (16a) in such a manner that at least one high-power secondary peak (20) of the diffraction due to the characteristic transverse dimension is destroyed.

Abstract: In a quasi-optical gyrotron an electron beam (1) passes along an electron beam axis (2) and in so doing is compressed by a static magnetic field and forced into gyration, so that it excites in a quasi-optical resonator a standing alternating electro-magnetic field of given frequency. The resonator exhibits two mirrors (4a, 4b) arranged opposite to one another on a resonator axis (5) aligned perpendicular to the electron beam axis (2). In order to generate radiation in a wide frequency range, each of the two mirrors (4a, 4b) of the resonator is arranged in each case on a movable mount (8a, 8b) together with at least one further mirror (4c, 4d). In order to set a specific frequency of the alternating field, it is possible for two mirrors (4c, 4d), corresponding to one another and tuned to the desired frequency, to be brought onto the resonator axis by actuating the movable mounts (8a, 8b).

Abstract: In a quasi-optical gyrotron, two coils (3a, 3b) in a Helmholtz arrangement generate a static magnetic field which is axially symmetrical with respect to an electron beam axis (2). As a result, the electrons passing along the electron beam axis (2) parallel to the magnetic field are forced into gyration and excite an alternating electromagnetic field in a quasi-optical resonator. The resonator comprises two mirrors (4a, 4b) which are arranged opposite to one another on a resonator axis (5) and which exhibit a superconducting reflective surface (6a, 6b). The resonator axis (5) is aligned perpendicularly to the electron beam axis (2) between the two coils (3a, 3b). So that the superconduction is not impaired by the strong magnetic field, means for suppressing the magnetic field at the location of the mirros (4a, 4b) are provided. These means preferably comprise a yoke (10) of a material having a high magnetic permeability.

Abstract: In a quasi-optical gyrotron which exhibits a quasi-optical resonator having two mirrors (4a, 4b) which opposite one another on a resonator axis (5), the required electromagnetic radiation is coupled out by means of a hologram. In this arrangement, at least one of the two mirrors (4b) of the resonator exhibits a reflective surface (8b) provided with a hologram. The hologram is constructed in such a manner that the radiation to be coupled out is scattered in the direction of at least exactly one coupling-out axis (10), the at least exactly one coupling-out axis (10) enclosing a predetermined angle .alpha. not equal to zero with the resonator axis (5). The angle .alpha. is preferably as small as possible.

Abstract: A coupling-out window for linearly polarized high-power microwaves exhibits at least one plate transparent to microwaves and cooling fins. The cooling fins are situated together with the plate in a plate plane and are aligned perpendicular to a direction of polarization of the microwaves. They are in heat-conducting and pressure-locking contact with the plate.