Patent ID: 8344626

Claim:
A microwave output transition for an electron tube comprising a body of tubular shape, along a longitudinal axis, having two ends, a passage between the two ends that has internal surfaces for propagating electromagnetic waves, one of the ends, in the form of a circular cylindrical tube, comprising a conical internal propagation surface and the other end, in the form of a tube of rectangular cross section, having two long sides and two short sides perpendicular to the long sides, the passage comprising two planar internal propagation surfaces parallel to the long sides and two planar internal surfaces parallel to the short sides, wherein each of the planar internal propagation surfaces parallel to the long sides is joined to the conical internal propagation surface via a respective curved connecting surface defined by a plurality of radii of horizontal curvature and a plurality of radii of vertical curvature, wherein each of the radii of horizontal curvature rotates about a respective rotation axis parallel to the short sides of the rectangular end of the body and each of the radii of vertical curvature rotates about a respective rotation axis parallel to the long sides of said rectangular end of the body.