The invention relates to a method for producing a bevel gear wheel, in particular for rudder propellers, the teeth of which have a macro geometry specific to the gear wheels, the teeth of which can be described by flank and profile lines, the flanks of which have a tooth flank micro topography and the bearing surface of which represents the contact region of the inter-meshing teeth. The crown of a tooth flank corresponds to the elevation of the tooth flank center with respect to the tooth flank edge, wherein the course of the height and width crowns of the flank surface is substantially shaped like a circular arc. By means of precise material removal, the micro topography of the tooth flank and thus the bearing surface is optimized firstly in that the material removal is carried out such that the end relief on the tooth flank surface is reduced toward the tooth heel side and the tooth toe side, an area having a greater length and width comes into engagement on the flank and thus an enlarged bearing surface is present, and secondly in that the course of the crown the crown of a tooth flank follows an approximately logarithmic, elliptical and/or an exponential curve shape, which runs through the point of contact, when the ease-off is viewed with no load, in a longitudinal section in the flank sectional surface and/or in a profile section in the profile sectional surface.

Methods of fly-cutting a workpiece are disclosed, and in methods in which the position of a fly-cutting head or its associated cutting element is known as a function of time. Also disclosed are methods of forming features, such as grooves or groove segments, in a workpiece such as a cylindrical roll. The features may be provided according to one or more disclosed patterns. Articles made using tools machined in the manner described are also provided, such as polymeric film or sheeting that exhibit certain beneficial properties.

A chip and shaving collection system for a key cutting machine has a trough with a linear first trough drawer rail located on a trough first side and a linear second trough drawer rail located on a trough second side. The trough further has a linear first trough support rail having a general shape of a triangular prism located on a trough first side and a linear second trough support rail having a general shape of a triangular prism located on a trough second side. The system has a plurality of linear support beams located on the support rails. The system has a rigid planar grid member spanning the trough top located on the linear support beams. The system has a drawer that is fluidly sealed located in the trough. The system has a key cutting machine located on the grid member.

A rotary joint device includes attachment grooves formed at positions in an outer peripheral surface of an outer cylinder, each attachment groove being formed so as to straddle a pair of adjacent cylindrical blocks and so as to be exposed from the outer peripheral surface of the outer cylinder, each attachment groove having a bottom surface that is machined to form a flat surface in a state in which the cylindrical blocks are combined, and positioning blocks corresponding to the attachment grooves on a one-to-one basis and each having an attachment phase that is uniquely set to a corresponding one of the attachment grooves in the axial direction and in a circumferential direction of the outer cylinder, each positioning block having an attachment surface corresponding to the bottom surface of a corresponding one of the attachment grooves, the attachment surface being machined so as to form a flat surface.

A machine tool having a motor-driven machine spindle which can be rotated about a spindle axis. The machine spindle has a tool holder arranged at the face. A tool is exchangeably arranged on the machine spindle. The tool has a coupling element which is compatible with the tool holder of the machine spindle. The coupling element has a rear surface pointing toward the machine spindle. The machine tool has at least one galvanic contact point for the electric current or data transmission, the point being arranged between the machine spindle and the tool and rotating together with the machine spindle. The galvanic contact point has a contact element which is arranged at the face of the tool holder on the spindle side, and a contact element which is arranged on the rear surface of the coupling element on the tool side.

A machining apparatus for grinding, milling, polishing or the like of a dental workpiece. The machining apparatus contains a machining tool, a housing to which the machining tool is mounted rotatably about an axis of rotation relative to the housing, and a holding device to which the housing is fixed. The housing is mounted yieldingly movably to the holding device in dependence on forces exerted on the machining tool.

A milling apparatus is provided for cutting desired contours into a workpiece. The apparatus comprises a head that moves relative to a workpiece in a direction of cut. Spindles are supported on the head for rotation about parallel spaced-apart spindle z axes and comprise respective rotary cutters adapted for use in machining operations. A rotary head positioner is configured to be operatively connected between the head and a milling machine and to rotate the head about a head axis. A stagger controller is connected to the rotary head positioner and is configured to provide a desired swath of a cut to be formed in a workpiece by rotating the head to set a corresponding spindle stagger angle value.

In a machine tool having a rotary shaft for use in rotating a tool or a workpiece, a plurality of stable rotation speeds at which the chatter vibrations are expected to be suppressed, and at least one switching rotation speed across which a dynamic characteristic of a rotary shaft system changes are stored. The plurality of stable rotation speeds may be determined from chatter vibrations detected using a vibration detection unit. Optimum rotation speed that is a rotation speed to which a rotation speed of the rotary shaft is changeable without crossing the switching rotation speed is selected from the plurality of stable rotation speeds, and the rotation speed of the rotary shaft is changed to the optimum rotation speed. Thus, chatter vibrations generated during rotation of the rotary shaft can be suppressed effectively.

A ram guiding apparatus 1 of a machine tool is incorporated in a portal type machine tool 2 and provided with a cross saddle 5 that is cross-like in shape, as seen in a side view of the machine tool 2, provided so as to be freely movable in the horizontal direction along a horizontal cross beam 4. The cross saddle 5 has a box 18, both upper and lower faces thereof being open, in a front side of a horizontal part, wherein a first linear guide 21, a second linear guide 22, and a third linear guide 23, respectively serving as linear guides in the box 18 for a ram vertical movement, guide the ram 9 so as to be freely movable only in the vertical direction.

A machine permits an end of a thick-walled, high-pressure tubing to be chucked in a collet one time, coned, faced and threaded, using a coning head and threading head which are mounted on a carriage which can be translated laterally between three positions and the coning and threading heads parallel to the longitudinal axis of the workpiece to complete the coning and threading operations.

A translocation-simulating loading apparatus for the gear grinding machine with the shaped grinding wheel is provided. The apparatus includes a load-receiving test piece disposed on the gear grinding machine with the shaped grinding wheel and a load-exerting component for use in loading simulation. The gear grinding machine enables linear movements along the X, Y, and Z axes, a rotary movement around the Y axis, a rotary movement C around the Z axis, and a rotary movement A around the X axis. An angle α is formed between the axis L of a ball seat of the load-exerting component and the X axis direction of a Y axis component and an angle formed between the normal line of a load receiving face a and the X direction of the coordinate system of the machine tool is α. A detection method for static stiffness distribution is provided.

In a pilot hole of a workpiece made of a difficult-to-cut cast iron, a cutting tool having a leading end to which a cutting insert is attached is inserted to cut the surface of the wall of the pilot hole. At this time, the cutting tool rotates about an axis (α) and also revolves about another axis (β), so that contouring is performed on the workpiece by the tool. The cutting insert is formed of a sintered body having a CBN content of not less than 85% by volume, and the cutting insert has a thermal conductivity of not less than 100 W/(mK).

A vibration damping mechanism allows increase of an absorption amount of vibration energy, with less possibilities of increase in the manufacture cost of a vibration damping weight and of reduction in the strength of a shaft section. Within a cylindrical hollow portion formed inside the shaft section, there are accommodated a plurality of weight members divided from each other along the circumferential direction about the axis of the hollow portion. An urging member is provided for urging the weight members toward the axis such that dividing faces of adjacent weight members are brought into surface contact with each other.

A method of machining bevel gears whereby machining of both flanks of a tooth slot and crowning of the tooth surfaces in the lengthwise direction are realized without an active pivot axis and by a modification of the conventional relationship between the radial and swivel basic settings during gear generating.

A cooling assembly for a machine tool including at least first and second nozzle rings mounted on the spindle housing, respectively defining first and second coolant conduits and respectively including first and second pluralities of nozzles in fluid communication with the respective conduit. Each first nozzle is oriented with an outlet thereof directed toward a first machining zone containing cutting edges of at last one tool having a first length. Each second nozzle is oriented with an outlet thereof directed toward a second machining zone different from the first machining zone and containing the cutting edges of at least one tool having a second length.

The present invention relates to a compensation system for compensating for the drop of the ram in a machine tool, comprising a vertical translation carriage (1) incorporating the application ram, at least one and preferably two perforated plates (2) being arranged on said carriage (1), on each of which there is incorporated a fixed sliding block (3) and movable sliding blocks (4), which blocks are linked with a guide for the transverse movement of the ram, such that the drop of the ram is compensated for by means of the controlled bending of the plates (2).

A master servo motor and a slave servo motor that synchronously drive for rotation a master main spindle provided with a center that supports one end of a work piece and a slave main spindle provided with a center that supports the other end of the work piece are included. Before grinding, a slip detection cycle that detects a limit current value for the servo motors, at which the work piece and the centers slip, is executed and, during grinding, a grinding condition is changed to prevent a slip between the work piece and the centers in advance at the time when any one of current values of the servo motors has reached a slip threshold value set on the basis of the limit current value.

A tool adapter includes an adaptor body having a connection portion structured to be attached to a machine tool and a holder portion disposed opposite the connection portion and a tool receiver structured to receive and couple a portion of a rotary cutting tool therein. The tool receiver is mounted in the holder portion so as to be rotatable to a limited extent. The tool receiver is mounted in the holder so as to be elastically resilient in both the axial and circumferential directions.

Apparatus, systems and methods of 50 CFM exhaust and ventilation fans for bathrooms with grill covers having removable light lens covers, and flaps/ears that allow the housings to mount directly to joists and/or other structural members inside of a ceiling or inside of a wall. The housing can include a mounting plate having a motor with attached impeller thereon, wherein the mounting plate with motor and attached impeller and electrical connectors can be removed as a single unit from the housing for accessing and inspecting interior wire connections during inspection and for ease in replacing parts such as burned out motors overtime.

The invention relates to a rotor for an axial flow pump for conveying a fluid having an axis of rotation and having an impeller blade which has at least one part surface which extends transversely to the axis of rotation and beyond it, wherein the impeller blade has throughgoing webs or a network of webs which connect a different marginal regions of the impeller blades to one another. A good compressibility is hereby achieved in the radial direction with high stability during operation.

A method for manufacturing a work piece is provided. The method includes preparing fiberglass in a mold, preparing a closed mold cavity around the fiberglass, flushing the closed mold cavity with an oxygen-free gas, injecting resin in the closed mold cavity, and curing the casted work piece. Furthermore, a work piece manufactured by the above method is provided.

An elongate web is attached to the root end of a spar of a wind turbine rotor blade to provide additional support along the width of the blade. The root end is formed by a winding operation, and a recess is then cut into the surface of the spar. The recess is defined by a relatively large first, cylindrical surface, which is coaxial with the longitudinal axis of the root end, and a relatively small second, conical surface. A tapered end of the elongate web is attached within the recess of the root end using a layer of suitable adhesive and an array of pins. Resilient spacer elements are arranged within the recess so as to surround the pins. The large area of the cylindrical surface causes the tensile and compressive stresses which arise along the elongate web in use to be transmitted to the spar as shear stresses.

The invention provides a method and system of monitoring bending strain on a wind turbine blade. The method in one aspect comprises: locating at least three strain sensors on the turbine blade, in use each strain sensor providing a strain measurement, the strain sensors located such that edgewise and flapwise bending can be determined from the strain measurements; calculating a plurality of resultant bending strains using the strain measurements; calculating an average resultant bending strain from the plurality of resultant bending strains; and calculating a confidence value for a first sensor based on a comparison of resultant bending strains derived from the strain measurement from the first sensor with the average resultant bending strain.

A blade for a rotor of a wind turbine is manufactured with a root region with a substantially circular or elliptical profile closest to the hub, an airfoil region with a lift generating profile furthest away from the hub and a transition region having a profile gradually changing the root region to the airfoil region. A first blade design is used for the first base part on a first longitudinal section of an airfoil region of a second blade, so that an induction factor of the first base part on the second blade deviates from a target induction factor. The first longitudinal section of the second blade is provided with flow altering devices so as to adjust the aerodynamic properties of the first longitudinal segment to substantially meet the target induction factor at the design point on the second blade.

A method is provided for operating a wind turbine having an elongated stand apparatus, a generator rotatably mounted on the stand apparatus, and a rotor coupled to the generator via a rotor hub and the wind turbine also having an elongated rotor blade. A position of a radar system is determined with respect to the wind turbine and at least one area is determined for the rotational axis of the rotor as a function of the determined position which is not intended to be permanently assumed for alignment of the rotational axis of the rotor about the longitudinal axis of the stand apparatus. The wind turbine is operated with the at least one determined area not being permanently assumed for the alignment of the rotational axis of the rotor about the longitudinal axis of the stand apparatus.

A wind turbine rotor includes a hub with a rotor blade mounted to a bearing of the hub wherein the rotor blade has a longitudinal axis extending in a radial direction relative to an axis of rotation of the hub, and the rotor blade is rotatable about its longitudinal axis whereby the pitch of the rotor blade is adjustable. The rotor blade has a tag such as an RFID tag fixed on the rotor blade at a predetermined angular position about the longitudinal axis of the rotor blade; and a sensor is fixed on the hub for contactless sensing of the tag when the tag is in a predetermined angular position about the longitudinal axis of the rotor blade. Repeated and accurate calibration of rotor blade pitch is hereby made possible.

A blade for use in water, the blade comprising an outer shell of fiber reinforced plastic defining a cavity. A substantial portion of the cavity is filled with a resin which adheres to the inner wall of the shell.

A propulsion device using fluid flow quickly discharges the vortex flow generated on an upper surface of the propulsion device to the outside to improve the propulsion and thrust of transportation means provided with the propulsion device. For this purpose, the propulsion device includes a fluid storage unit in which a downwardly curved fluid storage surface is formed between a first inlet line and a first outlet line such that a fluid storage space is formed on the fluid storage surface. A fluid flow unit in which a downwardly curved fluid flow surface is formed between a second inlet line and a second outlet line which are outwardly and backwardly inclined such that a fluid flow space is formed on the fluid flow surface. The-fluid flow surface adjacent to the second outlet line becomes gradually flattened as it extends outwardly.

A mechanism compressing a sealing ring of a cooling circuit of blades of a turbine engine against a turbine wheel supporting the blades, the wheel supporting on a downstream surface thereof an annular flange positioned radially and defining with the surface a groove configured to house the sealing ring. The flange includes at least two cut-outs on the edge thereof located opposite the bottom of the groove, to form windows for axial insertion in the groove for claws supported by the circumference of the ring facing the groove of the wheel. The mechanism includes a bolt tab configured to be positioned in the groove between the surface of the wheel and the ring, and a clamping shaped to be supported by the surface of the wheel and to engage with the bolt to ensure that the ring is compressed against the flange.

A rotating airfoil component of a turbomachine, in which the component has an airfoil aligned in a spanwise direction of the component, a shank, and a platform therebetween oriented transverse to the spanwise direction. The platform has an outer radial surface adjacent the airfoil, and at least one recessed region defined in its outer radial surface. The recessed region extends opposite the spanwise direction from a platform plane that contains portions of the outer radial surface that are upstream and downstream from the recessed region. The recessed region is contiguous with an end wall of the platform and extends therefrom toward the airfoil. The recessed region defines a surface shape whose boundary is contained by the platform plane, and has a profile shape that extends from the end wall toward the airfoil. The recessed region is sized and shaped to increase the stiffness of the platform.

A turbomachine blade or vane is made of composite material including fiber reinforcement obtained by three-dimensional weaving of yarns and densified by a matrix. The blade or vane includes a first portion constituting at least an airfoil exhibiting two faces each connecting a leading edge to a trailing edge, the first portion forming a single part with at least one second portion present only on one of the faces of the airfoil, the second portion constituting a portion of at least one of the following elements: a flowpath delimiting outer portion of an inner platform, an inner portion of an inner platform, a flowpath delimiting inner portion of an outer platform, and an outer portion of an outer platform, the portions of the fiber reinforcement corresponding to the first and the second portions of the blade being at least partially mutually imbricated, with yarns of the first portion of the fiber reinforcement penetrating into the second portion of the fiber reinforcement.

Provided is a propeller fan including a hub having an oval shape in an axial direction, a plurality of wings that extend from the hub, and at least one reinforcement rib that extends from the hub and is formed closer to a leading edge of each of the plurality of wings. Through this configuration, the propeller fan has blowing efficiency and stiffness, and the weight and material cost of the propeller fan can be reduced.

A seal assembly between a disc cavity and a turbine section hot gas path includes a stationary vane assembly and a rotating blade assembly downstream from the vane assembly and including a plurality of blades that are supported on a platform and rotate with a turbine rotor and the platform during operation of the engine. The platform includes a radially outwardly facing first surface, a radially inwardly facing second surface, a third surface, and a plurality of grooves extending into the third surface. The grooves are arranged such that a space is defined between adjacent grooves. During operation of the engine, the grooves guide purge air out of the disc cavity toward the hot gas path such that the purge air flows in a desired direction with reference to a direction of hot gas flow through the hot gas path.

The invention involves a wind turbine comprising at least one blade (5) in turn comprising a blade body (501), lift-regulating means (502) adapted for movement in relation to the blade body (501) so as to regulate the lift of the blade, and load sensing means (5022, 506) for determining a load acting on the lift-regulating means (502), the wind turbine further comprising an actuation control unit (6) adapted to control the movement of the lift-regulating means (502) based on output from the load sensing means (5022, 506). In addition to output from the load sensing means (5022, 506), the actuation control unit (6) is adapted to control the movement of the lift-regulating means (502) based on the movement of the lift-regulating means (502).

A gas turbine engine component, including: a pressure side (12) having an interior surface (34); a suction side (14) having an interior surface (36); a trailing edge portion (30); and a plurality of suction side and pressure side impingement orifices (24) disposed in the trailing edge portion (30). Each suction side impingement orifice is configured to direct an impingement jet (48) at an acute angle (52) onto a target area (60) that encompasses a tip (140) of a chevron (122) within a chevron arrangement (120) formed in the suction side interior surface. Each pressure side impingement orifice is configured to direct an impingement jet at an acute angle onto an elongated target area that encompasses a tip of a chevron within a chevron arrangement formed in the pressure side interior surface.

Turbine blade assemblies of a turbine include airfoils that are mounted on bases. The leading and/or trailing edges of the bases are provided with curved portions. Likewise, curved portions may be provided on leading and/or trailing edges of the angle wings of a turbine blade assembly. Also, curved portions may be provided on the leading and/or trailing edges of nozzle assemblies of a turbine.

A support ring for a rotary assembly such as a propeller assembly includes support cups for receiving blade roots of propeller blades. The support cups are interconnected by bridging structures. Each bridging structure includes bridging walls which extend radially from a bridging web. The bridging structures thus have a channel-shaped cross-section. The bridging walls have a scalloped configuration at their radially outer edges. As a result of this configuration, the neutral axes of the bridging structures are straight, so that the support ring behaves, in structural terms, as a polygon.

In general terms, embodiments of the present invention relate to fan assemblies and methods for installing the same. For example, some embodiments of the present invention include a fan assembly that includes: (a) a rotational member; (b) a connection member structured for connection to the rotational member and including a body portion and a head portion; and (c) a blade arm defining an opening therein, such that the opening includes an open end portion and a closed end portion. In some embodiments, the connection member and the blade arm are configured such that, (a) when the blade arm is positioned in a support state, the head portion of the connection member rests against the blade arm to support the blade arm relative to the rotational member, and (b) when the blade arm is positioned in a secure state, the head portion of the connection member at least partially bears against the blade arm adjacent to the opening defined in the blade arm. Also, some of these embodiments of the present invention may be characterized as “easy install” fan assemblies because they include an “easy install” blade arm to motor connection, as described above, and/or an “easy install” blade arm to fan blade connection.

A liner for a composite blade of a gas turbine engine includes a metallic shoe, operable substantially to encase a blade root of a composite blade and defining an inner surface and an outer surface. The liner also includes a retention lug formed on the shoe and has inner and outer keys that project from opposed portions of the inner and outer surfaces. The keys engage corresponding recesses on a dovetail slot and a blade root to resist axial displacement of the composite blade.

A winglet for a rotor blade is disclosed. The winglet may generally include a winglet body extending between a first end and a second end. The winglet body may define a sweep and may have a curvature defined by a curve fit including a first radius of curvature and a second radius of curvature. The sweep between the first end and the second end may range from about 580 millimeters to about 970 millimeters. Additionally, the first radius of curvature may range from about 1500 millimeters to about 2500 millimeters and the second radius of curvature may range from about 1200 millimeters to about 2000 millimeters.

A wind turbine for generating electrical energy may include a wind turbine blade including a plurality of vortex generators integrally formed in the outer surface of the blade. The vortex generator includes a first component that defines a portion of the outer surface of the blade and a second component defining the shape of the vortex generator and at least partially surrounded by the first component. A method of manufacturing the wind turbine blade includes disposing a first plurality of layers of structural material over a mold main body and a removable insert member with a shaped cavity. A shaped plug is then pressed into the shaped cavity, and a second plurality of layers of structural material is disposed over the plug and the mold main body to complete manufacture of a wind turbine blade with a vortex generator.

A wind turbine blade with a lightning protection for a blade with a shell body has at least one lightning receptor arranged freely accessible in or on a surface of the shell body surface, and a lightning down conductor electrically connected to the lightning receptor and comprising an inner conductor made of electrically conductive material imbedded in a bedding insulation made of an electrically non-conductive material. The lightning down conductor further includes a first conductive layer having a resistance in the range of 10 to 10,000 Mega Ohm per meter (MΩ/m). The first conductive layer is located in a transverse distance from the inner conductor and being electrically isolated from the inner conductor.

A cooled turbine blade comprises a root for fixing the blade to rotor, an airfoil extending along a radial axis from the root, and a tip shroud disposed at a radially outward end of the airfoil. The tip shroud extends in a circumferential direction from the airfoil and defines, within itself, a core plenum and a peripheral plenum. The airfoil defines an aft airfoil cooling passage that extends radially through the airfoil proximate a trailing edge portion of the airfoil. The airfoil also defines an aft cooling inlet for providing an aft stream of cooling fluid to the aft airfoil cooling passage. The airfoil also defines at least one aft cooling exit for discharging the aft stream of cooling fluid from the aft airflow cooling passage to the peripheral plenum. The tip shroud defines at least one peripheral plenum vent for discharging the aft stream of cooling fluid.

Medical imaging equipment is provided. The medical imaging equipment comprises a support assembly, an arc-shaped member slidably mounted on the support assembly, a radiation source mounted on the arc-shaped member in the vicinity of a first distal end of the arc-shaped member and being oriented to radiate along the direction of an imaging axis, and a detector mounted on the arc-shaped member in the vicinity of the second distal end of the arc-shaped member and being oriented to face the source along the imaging axis, wherein the radiation source and the detector are respectively mounted on one side and the other of the mid plane of the arc-shaped member.

A system and method for nodule boundary visualization superimposed on a scan image, including generating phantom image measurements of at least one synthetic calibration object in relation to a body to calibrate a scanner; acquiring a first image of a nodule on the calibrated scanner; computing and marking a boundary on the image; displaying the first image with the boundary superimposed over the first image; presenting the initial boundary to a user for modification where the user can add one or more modification points to the image to create a modified boundary that is encompassed by the one or more modification points; once the user has marked the one or more modification points on the image, computing an updated boundary that adapts to include the new points.

A machine-implemented display method that, with respect to a volume dataset being rendered, enables a user to navigate to any position in space and look in any direction. Preferably, the volume dataset is derived from a computer tomography (CT) or magnetic resonance imaging (MRI) scan. With the described approach, the user can see details within the dataset that are not available using conventional visualization approaches. The freedom-of-motion capability allows the user to go to places (positions) within the volume rendering that are not otherwise possible using conventional “orbit” and “zoom” display techniques. Thus, for example, using the described approach, the display image enables a user to travel inside physical structures (e.g., a patient's heart, brain, arteries, and the like).

A method is provided for constructing a tomographic reconstruction through the application of statistical inversion. Unknowns associated with points of a reconstruction grid are represented with components of a vector-valued variable. A next version of the vector-valued variable is repeatedly created by drawing for each component a value from a conditional distribution. The components of a so generated version of the vector-valued variable are used as the tomographic reconstruction. The components are divided into sets, so that components in a set represent unknowns associated with mutually independent points of the reconstruction grid, or into independent collections. For at least two components of a set or at least two collections, the drawing of values from a conditional distribution is performed in parallel in a computer-implemented process.

The present invention pertains to a system and method for X-ray imaging wherein a targeted fluence at the detector for projection images can be achieved at a plurality of projection angles around the imaging subject by control of exposure times implemented during image acquisition. Exposure time for a second projection image may be determined by the fluence in a first projection image, and in a third projection image by the fluence in a second projection image, where projection images are acquired within two degrees of one another. An acquisition parameter calculation can be configured to calculate acquisition parameters, such as said exposure times, to achieve the targeted fluence in projection images and can be coupled to a rotation controller that implements the acquisition parameters by controlling a relative angle between the imaging subject and X-ray image acquisition device.

A system and method is provided for estimating the local noise of CT images and denoising the images using a modified non-local means (NLM) algorithm that is adaptive to local variations of noise levels. A strategy for efficiently estimating the local noise of CT images is also described.

A mirror for the EUV wavelength range (1) having a layer arrangement (P) applied on a substrate (S), the layer arrangement having a periodic sequence of individual layers, where the periodic sequence has at least two individual layers—forming a period—composed respectively of silicon (Si) and ruthenium (Ru). Also disclosed are a projection objective for microlithography (2) including such a mirror, and a projection exposure apparatus for microlithography having such a projection objective (2).