Abstract: A positioning device configured to displace an object is disclosed. The positioning device comprises a stage to support the object, an actuator to move the stage with respect to a reference in a direction of movement, a balance mass arranged between the actuator and the reference to reduce transfer of reaction forces from the actuator to the reference, a support device arranged between the reference and the balance mass to support the balance mass, and a gravity compensator acting between the reference and the balance mass to exert a lifting force on the balance mass to reduce a gravitational support force to be provided by the support device to support the balance mass.

Abstract: A positioning device configured to displace an object is disclosed. The positioning device comprises a stage to support the object, an actuator to move the stage with respect to a reference in a direction of movement, a balance mass arranged between the actuator and the reference to reduce transfer of reaction forces from the actuator to the reference, a support device arranged between the reference and the balance mass to support the balance mass, and a gravity compensator acting between the reference and the balance mass to exert a lifting force on the balance mass to reduce a gravitational support force to be provided by the support device to support the balance mass.

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 (370). A moving part includes a permanent magnet (362) 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. A ferromagnetic shield (820) is provided around the moving part and has at least one interruption (822) to reduce the influence of adjacent actuators or stray fields while also minimizing attraction between the permanent magnet (362) and the shield (820).

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: An actuator to displace, for example a mirror, provides movement with at least two degrees of freedom by varying the currents in two electromagnets (370). A moving part includes a permanent magnet (362) 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. A ferromagnetic shield (820) is provided around the moving part and has at least one interruption (822) to reduce the influence of adjacent actuators or stray fields whilst also minimizing attraction between the permanent magnet (362) and the shield (820).

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 lithographic apparatus arranged to transfer a pattern from a patterning device onto a substrate. The apparatus includes an optical element, and at least two clamping assemblies for clamping the optical element. The clamping assemblies each include a first clamp with a first clamping surface in contact with a first surface of the optical element and a second clamp with a second clamping surface in contact with a second surface of said optical element, opposite said first surface of said optical element.

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.