Abstract: An actuator to displace, for example a mirror, provides movement with at least two degrees of freedom by varying the currents in two electromagnets. A moving part includes a permanent magnet with a magnetic face constrained to move over a working area lying substantially in a first plane perpendicular to a direction of magnetization of the magnet. The electromagnets have pole faces lying substantially in a second plane closely parallel to the first plane, each pole face substantially filling a quadrant of the area traversed by the face of the moving magnet. An optical position sensor may direct a beam of radiation at the moving magnet through a central space between the electromagnets. The sizes of facets in a pupil mirror device may be made smaller in a peripheral region, but larger in a central region, thereby relaxing focusing requirements.

Abstract: An EUV optical apparatus includes a number of adjustable mirrors (22x) on mirror bodies (120). Each mirror body is supported on an actuator (100x) comprising a moving part (132, 134, 136) and a fixed casing part (128, 130). The actuator provides a resilient support (140, 142) for the mirror body so that it is tiltable with two degrees relative to the casing. An electromagnetic motor (166, 170-178) applies first part, under the influence of an applied motive force, the resilient mounting being arranged to provide a biasing force that resists said motive force. A magnetic coupling (102, 104a, 104b) is arranged between the moving and fixed parts so as to provide a counter-biasing force. The counter-biasing force partly opposes said biasing force and thereby reduces the motive force required to effect a given displacement. The actuator can thus be made with reduced size, weight and heat dissipation.

Abstract: A reluctance actuator assembly comprising a reluctance actuator, a flux sensor to measure a magnetic flux in a gap of the reluctance actuator, and a flux amplifier to drive an actuator coil of the reluctance actuator based on a flux set point and the flux measured by the flux sensor. A method comprising providing to the flux amplifier a flux setpoint, the flux setpoint comprising a time constant component and a sinusoidally varying component at an excitation frequency, measuring a force generated by the reluctance actuator in response to the flux setpoint, and calibrating the reluctance actuator assembly from the measured force.

Abstract: A lithographic apparatus includes an illumination system configured to condition a radiation beam and a support constructed to support a patterning device, the patterning device being capable of imparting the radiation beam with a pattern in its cross-section to form a patterned radiation beam. The lithographic apparatus further includes a substrate table constructed to hold a substrate; a positioner constructed to position the substrate table; a projection system configured to project the patterned radiation beam onto a target portion of the substrate; a substrate surface actuator arranged to engage a part of a surface of the substrate facing the projection system, and a position controller configured to control a position of the substrate table, the position controller being arranged to drive the positioner and the substrate surface actuator.

Abstract: A support for a movable element includes a stator element, a gravity compensator field inducing element mounted on the stator element, the gravity compensator field inducing element configured to apply a translational force to the movable element by controlling a magnetic field in a gap between the stator element and the movable element, and a plurality of torque compensator field inducing elements mounted on the stator element, the torque compensator field inducing elements configured to apply a torque to the movable element by controlling a magnetic field in the gap between the stator element and the movable element, the torque being about a first axis substantially perpendicular to the direction of the translational force applied by the gravity compensator field inducing element.

Abstract: A variable reluctance device includes first and second magnetic members, a coil, a measurement coil, and a control unit. The first and second magnetic members are displaceable relative to each other to provide a magnetic circuit having a variable reluctance. The coil for, in use, receiving a current for generating a magnetic flux through the magnetic circuit. The measurement coil for generating a measurement signal representative of the magnetic flux through the magnetic circuit, whereby the measurement coil is arranged to substantially enclose the magnetic flux through the magnetic circuit. The control unit arranged to receive the flux signal at an input terminal and, in response, provide a control signal based on the measurement signal at an output terminal for controlling an amplitude of the current or a force of a further device. The device can e.g., be applied in a stage apparatus or a lithographic apparatus.

Abstract: A lithographic apparatus comprises a system. The system comprises a first part, a second part and an energy absorbing element. The second part is configured to move relatively to the first part. The system has a gap located between the first part and the second part during an operation mode of the system. The energy absorbing element is for absorbing energy between the first part and the second part when the first part and the second part crash onto each other in a failure mode of the system. The energy absorbing element is outside the gap.

Abstract: A method for positioning a substage, supported by a main stage, relative to a reference object, the substage moveable in a direction between a first and second position relative to the main stage. The method includes positioning the first stage using a passive force system that is activated by positioning the main stage. The passive force system includes two magnet systems, each magnet system being configured to apply a force in the direction to the first stage with respect to the second stage in a non-contact manner, the forces resulting in a resultant force applied to the first stage in the direction by the passive force system. A magnitude and/or a direction of the resultant force depends on the position of the first stage relative to the second stage, and the first stage has a zero-force position between the first and second position in which the resultant force is zero.

Abstract: An exposure apparatus including a projection system configured to project a plurality of radiation beams onto a target; a movable frame that is at least rotatable around an axis; and an actuator system configured to displace the movable frame to an axis away from an axis corresponding to the geometric center of the movable frame and to cause the frame to rotate around an axis through the center of mass of the frame.

Abstract: An electromagnetic actuator includes a first and second magnetic members that are displaceable relative to each other and are arranged to provide a magnetic circuit; and a coil configured to, in use, receive a current to generate a magnetic flux through the magnetic circuit, thereby generating a force between the first and second magnetic members in a first direction, the magnetic flux, in use, being transferred between the first and second magnetic members through a first surface of the first magnetic member and a second surface of the second magnetic member, the first and second surface being separated by an airgap, wherein the first surface and the second surface are arranged relative to each other such that an outer dimension of the first surface extends beyond an outer dimension of the second surface in a second direction substantially perpendicular to the first direction.

Abstract: A lithographic apparatus includes an actuator for producing a force in a first direction between a first and a second part including a first magnet assembly and a second magnet assembly each attached opposite to each other to the first part of the apparatus, the first magnet assembly including a first main magnet system and a first outer subsidiary magnet system, and the second magnet assembly including a second main magnet system and a second outer subsidiary magnet system, the first and second main magnet system defining a space between them in a second direction perpendicular to the first direction. The actuator includes a coil attached to the second part. The distance between the first outer subsidiary magnet system and the second outer subsidiary magnet system in the second direction is substantially zero.

Abstract: Actuator for exerting a force and a torque on an object, wherein the actuator includes a first part that is movable with respect to a second part of the actuator in at least a first degree of freedom, wherein the object is mounted to the first part, wherein one of the parts is provided with a first electrical coil that is arranged to cooperate with a magnetizable portion of the other part and wherein a controller of the actuator is arranged to generate a first electrical current through the first electrical coil for generating a force between the parts, wherein the one of the parts is provided with a second electrical coil which is arranged to cooperated with a magnetizable portion of the other part, wherein the controller is further arranged to generate a second current through the second coil and the first current through the first electrical coil for exerting the force and torque between the parts so that the actuator is arranged to exert the force and the torque on the object with respect to the second pa

Abstract: A lithographic apparatus includes a projection system, a substrate table, a plurality of sensors, an actuator and a controller. The projection system is configured to project a patterned beam of radiation onto a substrate. The substrate table is configured to support the substrate and to move relative to the projection system. The plurality of sensors is configured to measure a deformation of the substrate table. The actuator is configured to deform the substrate table. The controller is configured to control the actuator to deform the substrate table based on measurements made by the sensors. The plurality of sensors is located on a first side of the substrate table opposite to a second side of the substrate table facing the projection system. The plurality of sensors is substantially stationary relative to the projection system.

Abstract: A lithographic apparatus includes an illumination system configured to condition a radiation beam and a support constructed to support a patterning device, the patterning device being capable of imparting the radiation beam with a pattern in its cross-section to form a patterned radiation beam. The lithographic apparatus further includes a substrate table constructed to hold a substrate; a positioner constructed to position the substrate table; a projection system configured to project the patterned radiation beam onto a target portion of the substrate; a substrate surface actuator arranged to engage a part of a surface of the substrate facing the projection system, and a position controller configured to control a position of the substrate table, the position controller being arranged to drive the positioner and the substrate surface actuator.

Abstract: A motor includes a stator including a plurality of stator poles arranged in a repetitive arrangement with a first pitch, the stator poles facing a first side of a plane of movement, and a mover including a plurality of mover poles arranged in a repetitive arrangement with a second pitch, the mover poles facing a second, opposite side of the plane of movement. The poles of the stator and/or the mover are provided with a winding to alter a magnetic field in the respective ones of the stator poles and the mover poles in response to an electric current through the respective winding. At least one of the stator and the mover includes a permanent magnet for generating a magnetic field extending from the permanent magnet via at least one respective pole of the stator and the mover to the other one of the stator and the mover and back.

Abstract: An electromagnetic actuator includes a first and second magnetic members that are displaceable relative to each other and are arranged to provide a magnetic circuit; and a coil configured to, in use, receive a current to generate a magnetic flux through the magnetic circuit, thereby generating a force between the first and second magnetic members in a first direction, the magnetic flux, in use, being transferred between the first and second magnetic members through a first surface of the first magnetic member and a second surface of the second magnetic member, the first and second surface being separated by an airgap, wherein the first surface and the second surface are arranged relative to each other such that an outer dimension of the first surface extends beyond an outer dimension of the second surface in a second direction substantially perpendicular to the first direction.

Abstract: A variable reluctance device includes first and second magnetic members, a coil, a measurement coil, and a control unit. The first and second magnetic members are displaceable relative to each other to provide a magnetic circuit having a variable reluctance. The coil for, in use, receiving a current for generating a magnetic flux through the magnetic circuit. The measurement coil for generating a measurement signal representative of the magnetic flux through the magnetic circuit, whereby the measurement coil is arranged to substantially enclose the magnetic flux through the magnetic circuit. The control unit arranged to receive the flux signal at an input terminal and, in response, provide a control signal based on the measurement signal at an output terminal for controlling an amplitude of the current or a force of a further device. The device can e.g., be applied in a stage apparatus or a lithographic apparatus.

Abstract: A cooling apparatus is described that has a first cooling structure, in thermal contact with a heat source having a temperature greater than a cool structure, including a channel through which a cooling fluid is passed, an isolator between the heat source and the cool structure, the isolator in thermal contact with the first cooling structure and including a material of low thermal conductivity, and a second cooling structure between the isolator and the cool structure, the second cooling structure including a channel through which cooling fluid is passed.

Abstract: A method for positioning a substage, supported by a main stage, relative to a reference object, the substage moveable in a direction between a first and second position relative to the main stage. The method includes positioning the first stage using a passive force system that is activated by positioning the main stage. The passive force system includes two magnet systems, each magnet system being configured to apply a force in the direction to the first stage with respect to the second stage in a non-contact manner, the forces resulting in a resultant force applied to the first stage in the direction by the passive force system. A magnitude and/or a direction of the resultant force depends on the position of the first stage relative to the second stage, and the first stage has a zero-force position between the first and second position in which the resultant force is zero.

Abstract: Actuator for exerting a force and a torque on an object, wherein the actuator includes a first part that is movable with respect to a second part of the actuator in at least a first degree of freedom, wherein the object is mounted to the first part, wherein one of the parts is provided with a first electrical coil that is arranged to cooperate with a magnetizable portion of the other part and wherein a controller of the actuator is arranged to generate a first electrical current through the first electrical coil for generating a force between the parts, wherein the one of the parts is provided with a second electrical coil which is arranged to cooperated with a magnetizable portion of the other part, wherein the controller is further arranged to generate a second current through the second coil and the first current through the first electrical coil for exerting the force and torque between the parts so that the actuator is arranged to exert the force and the torque on the object with respect to the second pa