Abstract: A magnetic bearing (108) with an axis of rotation (106), wherein the magnetic bearing comprises: a cylindrical rotor (116) comprising a ferromagnetic material (118, 338, 440) wherein the cylindrical rotor has an axis of symmetry (114), wherein the cylindrical rotor has an inner radius (124), wherein the cylindrical rotor has a top side (128), a static hub (120), wherein the static hub has an overhang (122) which protrudes from the static hub and is located adjacent to the top side, a lift magnetic actuator apparatus (130) for controlling the distance (126) between the top side and the overhang, a radial magnetic actuator apparatus (132) for controlling the distance (136) between the inner radius and the axis of rotation.

Abstract: A magnetic bearing (108) with an axis of rotation (106), wherein the magnetic bearing comprises: a cylindrical rotor (116) comprising a ferromagnetic material (118, 338, 440) wherein the cylindrical rotor has an axis of symmetry (114), wherein the cylindrical rotor has an inner radius (124), wherein the cylindrical rotor has a top side (128), a static hub (120), wherein the static hub has an overhang (122) which protrudes from the static hub and is located adjacent to the top side, a lift magnetic actuator apparatus (130) for controlling the distance (126) between the top side and the overhang, a radial magnetic actuator apparatus (132) for controlling the distance (136) between the inner radius and the axis of rotation.

Abstract: An inspection apparatus for measuring a property of a substrate (W), includes a base frame, a substrate table (51) to hold the substrate, an illumination system arranged to direct a beam of radiation onto the substrate and a sensor arranged to detect radiation reflected off the substrate. Two balanced positioning systems displace the substrate table and sensor relative to the base frame in several directions. Each balanced positioning system includes a balance mass (59, 61), a bearing arrangement (65) to movably support the balance mass and tracks effective to guide the displacement in each direction. A motor arrangement causes the displacement in each direction. The balance mass is positioned relative to the track arrangement such that the centers of gravity of each balance mass and the substrate table or the sensor are substantially aligned in the direction substantially perpendicular to the plane including the direction of displacement.

Abstract: A substrate table positioning device that is supported by four bearing elements is provided. The substrate table positioning device also includes a balance mass. Two of the bearing elements support the base frame in such a way that they can move in a vertical direction independently of the other bearing elements. This can be achieved by using a hinge. This structure of substrate table positioning device has a higher lowest Eigen frequency of oscillation than that of substrate table positioning devices supported by three bearing elements. As such, the balance mass is not excited by typical vibrations that occur in the lithographic apparatus. This enables better positional control of the substrate table. It also enables at least some of the dimensions of the frame elements of the balance mass to be reduced.

Abstract: The invention relates to a medical imaging system comprising a frame (1) which accommodates an imaging device and an examination volume (7). The system further comprises a patient support member (13), a first displacement device (31) for displacing the patient support member relative to the frame in a first horizontal direction (X) into and out of the examination volume, and a second displacement device (33) ford is placing the patient support member relative to the frame in a second horizontal direction (Y) transverse to the first horizontal direction. The patient support member is provided on a mobile carrier (15) which comprises a first docking member (19) by means of which the mobile carrier can be docked to a second docking member (21) provided on the frame. According to the invention, the second displacement device (33) is provided on the frame (1) for displacing the second docking member (21) relative to the frame in the second horizontal direction (Y).