Abstract: A seismic shaker is described, the seismic shaker comprising:—a base plate;—an electromagnetic motor comprising a mover and a stator, the stator being mounted to the base plate, and—a guiding mechanism comprising a plurality of rods connecting the stator to the mover, the guiding mechanism being configured to enable a displacement of the mover relative to the stator in a first direction and restrict a displacement in a plane substantially perpendicular to the first direction.

Abstract: There is provided electromagnetic actuator. The electromagnetic actuator comprises a mover, a tubular coil and a tubular coil holder. The mover has a magnet. The tubular coil holder holds the tubular coil. The tubular coil holder has a cylindrical inner space for receiving the mover. The tubular coil and the magnet are configured to cooperate with each other to generate a force to move the mover relative to the coil holder along an axial axis. The mover comprises a ferromagnetic element arranged to change an inductance of the tubular coil in dependency on a position of the mover relative to the tubular coil holder. Further, there is provided a valve for opening and closing a conduit. The valve comprises the electromagnetic actuator.

Abstract: A coil assembly for a magnetic actuator is described, the coil assembly comprising: —a tubular coil holder (100) comprising a first (110) and second open distal end (120); —the first open distal end comprising an outer circular rim (112) and an inner circular rim (114) separated by a circular groove (116); —the second open distal end comprising an outer circular rim (122); the tubular coil holder further comprising a central circular rim (130) arranged substantially halfway between the inner circular rim of the first open distal end and the outer circular rim of the second open distal end; —a coil (140) formed of a single wire (150) the coil comprising a first coil section (142) arranged in a first winding area (144) between the inner circular rim of the first open distal end and the central circular rim, and a second coil section (146) in a second winding area (148) between the central circular rim and the outer circular rim of the second distal end; the first coil section and the second coil section being w

Abstract: A coil assembly for a magnetic actuator is described, the coil assembly comprising: a tubular coil holder (100) comprising a first (110) and second open distal end (120): the first open distal end comprising an outer circular rim (112) and an inner circular rim (114) separated by a circular groove (116): the second open distal end comprising an outer circular rim (122); the tubular coil holder further comprising a central circular rim (130) arranged substantially halfway between the inner circular rim of the first open distal end and the outer circular rim of the second open distal end: a coil (140) formed of a single wire (150) the coil comprising a first coil section (142) arranged in a first winding area (144) between the inner circular rim of the first open distal end and the central circular rim, and a second coil section (146) in a second winding area (148) between the central circular rim and the outer circular rim of the second distal end; the first coil section and the second coil section being wound

Abstract: An actuator includes coil assemblies arranged in an array, wherein each coil assembly defines a core chamber having a core chamber height; and at least one magnetic member that extends partly along the core chamber height of the core chamber of a corresponding at least one coil assembly, wherein the at least one magnetic member is made of a magnetic material. A shape of the at least one magnetic member, a size of the at least one magnetic member, a position of the at least one magnetic member and/or the magnetic material of the at least one magnetic member may be selected so as to control one or more parameters of the actuator.

Abstract: An actuator includes coil assemblies arranged in an array, wherein each coil assembly defines a core chamber having a core chamber height; and at least one magnetic member that extends partly along the core chamber height of the core chamber of a corresponding at least one coil assembly, wherein the at least one magnetic member is made of a magnetic material. A shape of the at least one magnetic member, a size of the at least one magnetic member, a position of the at least one magnetic member and/or the magnetic material of the at least one magnetic member may be selected so as to control one or more parameters of the actuator.

Abstract: A speed sensor has a static part and a dynamic part arranged concentrically inside the static part. The static part has two permanent magnets and the dynamic part has two further permanent magnets. The magnet is oriented reversely to the further magnets. The magnets are tuned to each other so that gravity on the dynamic part is counteracted by the magnetic force on the dynamic part. As a result, the weight of the dynamic part need not be carried by springs and the dynamic part can move freely so that the full stroke can be used for measuring accelerations and the natural frequency is low. The static part further includes a measuring coil for measuring the displacement of the dynamic part and for the radial positioning of the dynamic part this part is connected to the static part by means of leaf springs.

Abstract: A magnetic actuator has a static part and a dynamic part concentrically arranged therein. The static part comprises two permanent magnets and the dynamic part comprises two further permanent magnets. The magnet is oppositely oriented to the further magnets. The magnets are tuned to each other in such a way that the gravity on the dynamic part is compensated by the magnetic force on the dynamic part. The static part further includes a coil with which an additional magnetic field can be generated by which the actuation force can be adapted.

Abstract: A method of preparing components for use in a vacuum chamber of a lithographic apparatus is disclosed. The method includes coating the component with a non-metallic material. The method may further include treating the coating so as to harden the coating. Preferably, the coating material is a hydrogen silsesquioxane (HSQ), which may be applied via spraying, brushing, or spinning and can be treated by heating or by irradiation with an electron beam. The resulting components strongly reduce outgassing of water and hydrocarbons when subjected to a vacuum environment.

Abstract: A speed sensor has a static part and a dynamic part arranged concentrically inside the static part. The static part has two permanent magnets and the dynamic part has two further permanent magnets. The magnet is oriented reversely to the further magnets. The magnets are tuned to each other so that gravity on the dynamic part is counteracted by the magnetic force on the dynamic part. As a result, the weight of the dynamic part need not be carried by springs and the dynamic part can move freely so that the full stroke can be used for measuring accelerations and the natural frequency is low. The static part further includes a measuring coil for measuring the displacement of the dynamic part and for the radial positioning of the dynamic part this part is connected to the static part by means of leaf springs.

Abstract: A gas bearing has a first bearing part defining a first bearing surface and a second bearing part defining a second bearing surface. Between the first bearing surface and the second bearing surface there is a gap. A gas supply device supplies a gas to the gap. The first bearing part is at least partly ferromagnetic, and the second bearing part has at least one permanent magnet interacting with the first bearing part for pre-tensioning the gas bearing. The gas bearing may be part of a lithographic apparatus.

Abstract: A magnetic actuator has a static part and a dynamic part concentrically arranged therein. The static part comprises two permanent magnets and the dynamic part comprises two further permanent magnets. The magnet is oppositely oriented to the further magnets. The magnets are tuned to each other in such a way that the gravity on the dynamic part is compensated by the magnetic force on the dynamic part. The static part further includes a coil with which an additional magnetic field can be generated by which the actuation force can be adapted.

Abstract: This invention relates to a magnet assembly that includes a ferromagnetic member extending in a first direction, an array of magnetized poles of opposite polarity arranged adjacent to each other in the first direction and mounted on the ferromagnetic member, wherein a magnetized pole of the array of magnetized poles includes a plurality of permanent magnets arranged to generate a diverging magnetic field towards the ferromagnetic member. In the magnet assembly, each permanent magnet of the magnetized pole has a magnetic polarization having a non-zero component in the first direction and a non-zero component in a second direction substantially perpendicular to the first direction.

Abstract: A lithographic apparatus is arranged to transfer a pattern from a patterning device onto a substrate and includes an electromagnetic actuator to actuate a part of the lithographic apparatus in a linear direction or in a rotational direction. The actuator has a substantially stationary part and a movable part interacting with each other. The stationary part has a plurality of coils and a magnetic circuit of magnetizable material, and the movable part has a magnet system. The magnet system has an array of magnets forming a magnet array having opposite ends. The magnet array has an array of primary magnets and an array of subsidiary magnets alternating with the primary magnets. A direction of polarization of an end primary magnet at an end position of the array of primary magnets differs from a direction of polarization of an intermediate primary magnet at an intermediate position between the end primary magnets.

Abstract: A positioning device for positioning an object table relative to a reference frame with a drive unit including a first part connectable to the reference frame and a second part for holding the object table is described. The drive unit is constructed to displace the object table in a first direction by generating a force in the first direction on the second part, and a torque acting on the second part about an axis substantially perpendicular to the first direction such that the resulting force of the force and the torque is directed substantially through the center of gravity of the assembly including the object table and the second part.

Abstract: A lithographic apparatus includes a guiding mechanism to guide a movable structure such as a mask blade of a reticle masking device, a movable part connected to the movable structure, and a substantially stationary part to guide the movable part. The movable part includes a nozzle to inject a gas in a gap between the movable and stationary parts, a contactless supply of the gas from the stationary part to the movable part being provided by a gas supply outlet in the stationary part and a gas supply inlet in the movable part. The gas supply outlet includes an inlet trench in a surface of the movable part facing the gas supply outlet of the stationary part, the trench being orientated parallel to a direction of movement of the movable part. The movable part includes a motor drive part and a counter weight part connected to an end of the motor drive part facing away from the movable structure.

Abstract: In a scanning exposure, the short stroke module accelerates the mask or substrate table with a higher acceleration that the long stroke module. The short stroke module starts at or near (proximate) one extreme of its range of motion and catches up to the long stroke module during the scan. The long stroke module starts to decelerate earlier but the short stroke decelerates faster so that the short stroke overtakes the long stroke and ends up at the other extreme of its range of motion. The acceleration times can be reduced without increasing the forces exerted by the long stroke actuators so there is less of an increase in dissipation and reaction forces.

Abstract: A method and a system for accurate positioning of an object are presented. An embodiment of the invention includes an electromagnetic actuator including a coil assembly. The coil assembly includes two coils that encloses a magnet assembly including a magnet that is magnetized in the direction of the generated force. The generated force is substantially constant over the operating range of the actuator. The actuator may further be equipped with a cooling body surrounding the coil assembly.

Abstract: This invention relates to a magnet assembly that includes a ferromagnetic member extending in a first direction, an array of magnetized poles of opposite polarity arranged adjacent to each other in the first direction and mounted on the ferromagnetic member, wherein a magnetized pole of the array of magnetized poles includes a plurality of permanent magnets arranged to generate a diverging magnetic field towards the ferromagnetic member. In the magnet assembly, each permanent magnet of the magnetized pole has a magnetic polarization having a non-zero component in the first direction and a non-zero component in a second direction substantially perpendicular to the first direction.

Abstract: A lithographic optical system is presented herein. The optical system comprises a housing with two optically transparent windows and at least one moveable lens therein, as well as at least one other optical element outside said housing. By providing at least one optical element outside the housing, possible deleterious influences thereof on the optical quality of the moveable lens may be diminished. The housing with the moveable lens may be purged, and may be provided with a linear motor and a gas bearing for contactless moving of the lens.