An adjustable inductor including a toroidal core defining a plurality of gaps, a compressible gap material positioned in the gaps, at least one winding wound on the core, a force-applying structure, and a film substantially covering the adjustable inductor. The force-applying structure is operable to apply a force to the core to adjust the gaps and thereby an inductance of the adjustable inductor. The film is configured to prevent movement of force-applying structure when above a predetermined temperature threshold, and allow movement of the force-applying structure when below the predetermined threshold.

A capacitively-coupled plasma processing apparatus includes: at least one chamber body providing chambers separated from each other; upper electrodes respectively installed in upper spaces within the chambers; lower electrodes respectively installed in lower spaces within the chambers; a high frequency power supply; a transformer including a primary coil electrically connected to the high frequency power supply, and secondary coils each of which coils having a first end and a second end; first condensers respectively connected between each of the first ends of the secondary coils and the upper electrodes; and second condensers respectively connected between each of the second ends of the secondary coils and the lower electrodes. The primary coil extends around a central axis. The secondary coils are configured to be coaxially disposed with respect to the primary coil. A self-inductance of each of the secondary coils is smaller than that of the primary coil.

A capacitively-coupled plasma processing apparatus includes: at least one chamber body providing chambers separated from each other; upper electrodes respectively installed in upper spaces within the chambers; lower electrodes respectively installed in lower spaces within the chambers; a high frequency power supply; a transformer including a primary coil electrically connected to the high frequency power supply, and secondary coils each of which coils having a first end and a second end; first condensers respectively connected between each of the first ends of the secondary coils and the upper electrodes; and second condensers respectively connected between each of the second ends of the secondary coils and the lower electrodes. The primary coil extends around a central axis. The secondary coils are configured to be coaxially disposed with respect to the primary coil. A self-inductance of each of the secondary coils is smaller than that of the primary coil.

A magnetic shell for a magnetic device juxtaposable to another shell form a magnetic core, wherein at least part of the surfaces of the magnetic shells meet when the shells are juxtaposed and form at least an air gap, wherein the magnetic core expands and contracts under temperature changes along a main expansion direction at the air gap, characterized in that the surfaces of the magnetic shells that meet to form the air gap are at least in part disposed parallel to the main expansion direction at the air gap.

A magnetic shell for a magnetic device juxtaposable to another shell form a magnetic core, wherein at least part of the surfaces of the magnetic shells meet when the shells are juxtaposed and form at least an air gap, wherein the magnetic core expands and contracts under temperature changes along a main expansion direction at the air gap, characterized in that the surfaces of the magnetic shells that meet to form the air gap are at least in part disposed parallel to the main expansion direction at the air gap.

A rotary variable differential transformer for measuring angular displacement and method of manufacturing the same are provided herein. The rotary variable differential transformer includes a stator configured to house a primary coil configured to receive an alternating current, a first secondary coil electromagnetically coupled to the primary coil, and a second secondary coil electromagnetically coupled to the primary coil. The rotary variable differential transformer also includes a rotor positioned concentrically within the stator. The rotor is configured to receive a shaft and rotate with the shaft while the stator remains stationary. The primary coil is positioned at a first radial position within the stator spaced between about 90 to 150 degrees from each of the first secondary coil and the second secondary coil.

A rotary variable differential transformer for measuring angular displacement and method of manufacturing the same are provided herein. The rotary variable differential transformer includes a stator configured to house a primary coil configured to receive an alternating current, a first secondary coil electromagnetically coupled to the primary coil, and a second secondary coil electromagnetically coupled to the primary coil. The rotary variable differential transformer also includes a rotor positioned concentrically within the stator. The rotor is configured to receive a shaft and rotate with the shaft while the stator remains stationary. The primary coil is positioned at a first radial position within the stator spaced between about 90 to 150 degrees from each of the first secondary coil and the second secondary coil.

An adjustable inductor including a core defining a plurality of gaps, a material positioned in the gaps, at least one winding wound on the core, a force-applying structure, and a film substantially covering the adjustable inductor. The force-applying structure is operable to apply a force to the core to adjust the gaps and thereby an inductance of the adjustable inductor. The film is configured to prevent movement of force-applying structure when below a predetermined temperature threshold, and allow movement of the force-applying structure when above the predetermined threshold.

An adjustable inductor including a core defining a plurality of gaps, a material positioned in the gaps, at least one winding wound on the core, a force-applying structure, and a film substantially covering the adjustable inductor. The force-applying structure is operable to apply a force to the core to adjust the gaps and thereby an inductance of the adjustable inductor. The film is configured to prevent movement of force-applying structure when below a predetermined temperature threshold, and allow movement of the force-applying structure when above the predetermined threshold.

A rotary variable differential transformer for measuring angular displacement and method of manufacturing the same are provided herein. The rotary variable differential transformer includes a stator configured to house a primary coil configured to receive an alternating current, a first secondary coil electromagnetically coupled to the primary coil, and a second secondary coil electromagnetically coupled to the primary coil. The rotary variable differential transformer also includes a rotor positioned concentrically within the stator. The rotor is configured to receive a shaft and rotate with the shaft while the stator remains stationary. The primary coil is positioned at a first radial position within the stator spaced between about 90 to 150 degrees from each of the first secondary coil and the second secondary coil.