Abstract: Apparatus for receiving electromagnetic radiation at various angles of incidence including an optical element for guiding the radiation upon a radiation detector, and magnetic drive means for adjusting the position of the optical element, characterized by the provision of a shock-resistant suspension for the magnet in the form of a plurality of linear elements in the form of coplanar taut wires or resilient bands that extend radially outwardly from and coplanar with the magnet, together with a plurality of stationary coils arranged circumferentially about the magnet, whereby the magnet can be pivoted about pivot axes, respectively, contained in the plane, and also be displaced in a direction normal to the plane (i.e., in the Z-direction).

Abstract: In order to avoid contamination of a bombarding plasma jet by the products f cathode erosion in a plasma gun having a cathode and an anode, with which a connecting plasma is produced which strikes vertically onto the bombarding plasma jet and flows through a cooled duct between the cathode and the bombarding plasma jet, it is suggested that the cathode should be located in an enclosed cavity, the duct emerging from a wall of this cavity and the cathode being laterally offset relative to the inlet port to the duct, and that a gas supply line should open into the duct between the inlet port and the end of the duct facing the bombarding plasma jet, gas being supplied through this supply line as a substitute for the deposited cathode material in order to maintain a substantially constant particle density in the connecting plasma.