Abstract: A waveguide absorber which withstands high mechanical and thermal loads is typified in that a member (4) exhibiting absorber material is clamped between waveguide walls (5, 6) in such a way that at least one wall region (5) adjoining the member (4) is constructed flexibly, and that a force acting on the flexible wall region (5) presses the latter against the member (4).

Abstract: A waveguide assembly includes a waveguide having walls defining a cavity; and a frame surrounding the walls of the waveguide. The frame has a coefficient of thermal expansion less than that of the waveguide. First and second connecting spacers are attached to and project away from oppositely located wall portions of the waveguide and are attached to the frame such that forces derived from a difference between a heat expansion of the frame and a heat expansion of the waveguide are transmitted by the first and second connecting spacers to the waveguide walls for deforming the same.