The invention relates to a rotary joint which comprises two components mounted for rotation relative to one another about an axis of rotation, and each comprising electrically conductive material and jointly enclosing at least one intermediate gap, which is in the form of a capacitive gap for the purpose of transmitting electrical signals and/or energy. The two components are mounted by means of at least one plain bearing such that they are axially fixed longitudinally relative to the axis of rotation and can be rotated relative to one another about the axis of rotation. The plain bearing has at least one plain bearing gap, at least some regions of which correspond to the capacitive gap. The invention is characterized in that the surface of at least one of the two components has, at least in the region of the capacitive gap, the electrically conductive material with an electrically insulating layer in the form of a metal oxide layer.

Electrical instrument for applying radiofrequency and/or microwave frequency energy to tissue, comprising: a distal part comprising an instrument tip for applying radiofrequency and/or microwave frequency energy to tissue, the instrument tip comprising first and second conductive elements; a coaxial feed cable comprising an inner conductor, a tubular outer conductor coaxial with the inner conductor, and dielectric material separating the inner and outer conductors, the coaxial feed cable being for conveying radiofrequency and/or microwave frequency energy to the distal part; wherein: the inner conductor is electrically connected to the first conductive element and the outer conductor is electrically connected to the second conductive element through a rotatable connection between the distal part and the coaxial feed cable that allows rotation of the distal part relative to the coaxial feed cable; and the instrument comprises an actuator for rotating the distal part in a first rotational direction relative to the feed cable.

Electrical instrument for applying radiofrequency and/or microwave frequency energy to tissue, comprising: a distal part comprising an instrument tip for applying radiofrequency and/or microwave frequency energy to tissue, the instrument tip comprising first and second conductive elements; a coaxial feed cable comprising an inner conductor, a tubular outer conductor coaxial with the inner conductor, and dielectric material separating the inner and outer conductors, the coaxial feed cable being for conveying radiofrequency and/or microwave frequency energy to the distal part; wherein: the inner conductor is electrically connected to the first conductive element and the outer conductor is electrically connected to the second conductive element through a rotatable connection between the distal part and the coaxial feed cable that allows rotation of the distal part relative to the coaxial feed cable; and the instrument comprises an actuator for rotating the distal part in a first rotational direction relative to the feed cable.

Electrical instrument for applying radiofrequency and/or microwave frequency energy to tissue, comprising: a distal part comprising an instrument tip for applying radiofrequency and/or microwave frequency energy to tissue, the instrument tip comprising first and second conductive elements; a coaxial feed cable comprising an inner conductor, a tubular outer conductor coaxial with the inner conductor, and dielectric material separating the inner and outer conductors, the coaxial feed cable being for conveying radiofrequency and/or microwave frequency energy to the distal part; wherein: the inner conductor is electrically connected to the first conductive element and the outer conductor is electrically connected to the second conductive element through a rotatable connection between the distal part and the coaxial feed cable that allows rotation of the distal part relative to the coaxial feed cable; and the instrument comprises an actuator for rotating the distal part in a first rotational direction relative to the feed cable.

Electrical instrument for applying radiofrequency and/or microwave frequency energy to tissue, comprising: a distal part comprising an instrument tip for applying radiofrequency and/or microwave frequency energy to tissue, the instrument tip comprising first and second conductive elements; a coaxial feed cable comprising an inner conductor, a tubular outer conductor coaxial with the inner conductor, and dielectric material separating the inner and outer conductors, the coaxial feed cable being for conveying radiofrequency and/or microwave frequency energy to the distal part; wherein: the inner conductor is electrically connected to the first conductive element and the outer conductor is electrically connected to the second conductive element through a rotatable connection between the distal part and the coaxial feed cable that allows rotation of the distal part relative to the coaxial feed cable; and the instrument comprises an actuator for rotating the distal part in a first rotational direction relative to the feed cable.

Electrical instrument for applying radiofrequency and/or microwave frequency energy to tissue, comprising: a distal part comprising an instrument tip for applying radiofrequency and/or microwave frequency energy to tissue, the instrument tip comprising first and second conductive elements; a coaxial feed cable comprising an inner conductor, a tubular outer conductor coaxial with the inner conductor, and dielectric material separating the inner and outer conductors, the coaxial feed cable being for conveying radiofrequency and/or microwave frequency energy to the distal part; wherein: the inner conductor is electrically connected to the first conductive element and the outer conductor is electrically connected to the second conductive element through a rotatable connection between the distal part and the coaxial feed cable that allows rotation of the distal part relative to the coaxial feed cable; and the instrument comprises an actuator for rotating the distal part in a first rotational direction relative to the feed cable.

Electrical instrument for applying radiofrequency and/or microwave frequency energy to tissue, comprising: a distal part comprising an instrument tip for applying radiofrequency and/or microwave frequency energy to tissue, the instrument tip comprising first and second conductive elements; a coaxial feed cable comprising an inner conductor, a tubular outer conductor coaxial with the inner conductor, and dielectric material separating the inner and outer conductors, the coaxial feed cable being for conveying radiofrequency and/or microwave frequency energy to the distal part; wherein: the inner conductor is electrically connected to the first conductive element and the outer conductor is electrically connected to the second conductive element through a rotatable connection between the distal part and the coaxial feed cable that allows rotation of the distal part relative to the coaxial feed cable; and the instrument comprises an actuator for rotating the distal part in a first rotational direction relative to the feed cable.

A tunable microwave system includes at least two elements, each element being chosen from a propagating guide, an evanescent guide, a resonator, and at least one coupling device arranged between the two elements and configured to couple the two elements to each other, the coupling device having a holder having an aperture and having at least one elongate element the shape of which is elongate in a polarization direction contained in a plane of the aperture, the elongate element being securely fastened to the perimeter of the aperture at at least one end, the coupling device being configured to be rotatable about an axis substantially perpendicular to the plane of the aperture so as to modify a value of the polarization direction and so that the coupling between the two elements is dependent on the value of the polarization direction.

A rotary joint according to an aspect of the present disclosure includes a first microstrip line, a second microstrip line, a transmitting circuit connected to one end of the first microstrip line and configured to output a communication signal, a transmitting-side terminator connected to the other end of the first microstrip line, a receiving-side terminator connected to one end of the second microstrip line, and a receiving circuit connected to the other end of the second microstrip line and configured to receive the communication signal, in which the first and second microstrip lines and are set along at least a part of a circular ring having a circumferential length equal to an integral multiple of a wavelength of a traveling wave with which the communication signal propagates through the microstrip lines.

A coupler provides a high speed datalink between rotatable parts, which includes comprising a circular gap shaped as a hollow-cylindric volume and at least two antennae. The gap is formed between a first ring and a second ring rotatable against the first ring. A first antenna is mechanically coupled to the first ring and a second antenna is mechanically coupled to the second ring. The antennae are configured to effectuate a microwave signal connection between them the antennae based on multiple reflections of the signal at the rings.