Abstract: A measurement apparatus (10) for measuring a wavefront aberration of an imaging optical system (12) includes (i) a measurement wave generating module (24) which generates a measurement wave (26) radiated onto the optical system and which includes an illumination system (30) illuminating a mask plane (14) with an illumination radiation (32), as well as coherence structures (36) arranged in the mask plane, and (ii) a wavefront measurement module (28) which measures the measurement wave after passing through the optical system and determines from the measurement result, with an evaluation device (46), a deviation of the wavefront of the measurement wave from a desired wavefront. The evaluation device (46) determines an influence of an intensity distribution (70) of the illumination radiation in the region of the mask plane on the measurement result and, when determining the deviation of the wavefront, utilizes the influence of the intensity distribution.

Abstract: The disclosed method involves: recording, under illumination of a diffractive measurement structure via an illumination device, a plurality of diffraction images which differ from one another in terms of the region of the measurement structure that contributes to the respective diffraction image, and ascertaining transmission properties and/or reflection properties of the diffractive measurement structure based on the plurality of diffraction images, wherein the steps of recording a plurality of diffraction images and of ascertaining transmission properties and/or reflection properties of the diffractive measurement structure in a plurality of recording sequences are carried out repeatedly in a plurality of recording sequences, wherein these recording sequences differ from one another with respect to the illumination angles that are respectively set during the illumination of the diffractive measurement structure and at which the diffractive measurement structure is illuminated.

Abstract: An appliance for moiré measurement of an object (12) includes a grating arrangement having a first grating (11) positioned upstream of the object and including test structures to be imaged, a second grating (14) positioned downstream of the object, and an evaluation unit having at least one detector evaluating moiré structures produced by superposing the two gratings in a detection plane situated downstream of the second grating. The object is an anamorphic imaging system, and the respective grating periods of the first grating and of the second grating are selected so that the grating period of the second grating corresponds to a common multiple or a common divisor of the respective periods of two test structure images of the test structures of the first grating produced by the imaging system in two different measurement positions. The two measurement positions differ in relative grating arrangement position and test object position.

Abstract: The disclosed method involves: recording, under illumination of a diffractive measurement structure (110, 210, 310, 410, 510, 610) via an illumination device, a plurality of diffraction images which differ from one another in terms of the region of the measurement structure that contributes to the respective diffraction image, and ascertaining transmission properties and/or reflection properties of the diffractive measurement structure based on the plurality of diffraction images, wherein the steps of recording a plurality of diffraction images and of ascertaining transmission properties and/or reflection properties of the diffractive measurement structure in a plurality of recording sequences are carried out repeatedly in a plurality of recording sequences, wherein these recording sequences differ from one another with respect to the illumination angles that are respectively set during the illumination of the diffractive measurement structure and at which the diffractive measurement structure is illuminated.

Abstract: A measurement apparatus (10) for measuring a wavefront aberration of an imaging optical system (12) includes (i) a measurement wave generating module (24) which generates a measurement wave (26) radiated onto the optical system and which includes an illumination system (30) illuminating a mask plane (14) with an illumination radiation (32), as well as coherence structures (36) arranged in the mask plane, and (ii) a wavefront measurement module (28) which measures the measurement wave after passing through the optical system and determines from the measurement result, with an evaluation device (46), a deviation of the wavefront of the measurement wave from a desired wavefront. The evaluation device (46) determines an influence of an intensity distribution (70) of the illumination radiation in the region of the mask plane on the measurement result and, when determining the deviation of the wavefront, utilizes the influence of the intensity distribution.

Abstract: An appliance for moiré measurement of an object (12) includes a grating arrangement having a first grating (11) positioned upstream of the object and including test structures to be imaged, a second grating (14) positioned downstream of the object, and an evaluation unit having at least one detector evaluating moiré structures produced by superposing the two gratings in a detection plane situated downstream of the second grating. The object is an anamorphic imaging system, and the respective grating periods of the first grating and of the second grating are selected so that the grating period of the second grating corresponds to a common multiple or a common divisor of the respective periods of two test structure images of the test structures of the first grating produced by the imaging system in two different measurement positions. The two measurement positions differ in relative grating arrangement position and test object position.

Abstract: An apparatus for the moiré measurement of an optical test object includes a grating arrangement made of a first grating (25, . . . ) which is positionable in the optical beam path upstream of the test object and a second grating (11, . . . ) which is positionable in the optical beam path downstream of the test object, an evaluation unit having at least one detector (12, . . . ), for evaluating moire structures produced by superposition of the two gratings in a detection plane situated downstream of the second grating in the optical beam path, and at least one aperture stop (14, . . . ), by way of which the light distribution which was produced after the light exit from the second grating can be shadowed in a region-wise fashion such that only light of a subset of all field points on the second grating reaches the detection plane.

Abstract: A measuring system (10) for measuring an imaging quality of an EUV lens (30) includes a diffractive test structure (26), a measurement light radiating device (16) which is configured to radiate measurement light (21) in the EUV wavelength range onto the test structure, a variation device (28) for varying at least one image-determining parameter of an imaging of the test structure that is effected by a lens, a detector (14) for recording an image stack including a plurality of images generated with different image-determining parameters being set, and an evaluation device (15) which is configured to determine the imaging quality of the lens from the image stack.

Abstract: A measuring system (10) for measuring an imaging quality of an EUV lens (30) includes a diffractive test structure (26), a measurement light radiating device (16) which is configured to radiate measurement light (21) in the EUV wavelength range onto the test structure, a variation device (28) for varying at least one image-determining parameter of an imaging of the test structure that is effected by a lens, a detector (14) for recording an image stack including a plurality of images generated with different image-determining parameters being set, and an evaluation device (15) which is configured to determine the imaging quality of the lens from the image stack.

Abstract: A tube structure, and a method for assembling the tube structure, is provided, that is particularly useful in a solar heating system. The tube structure comprises, (a) a tube formed into a predetermined (e.g. coiled) configuration, (b) at least one rafter which engages the tube in a manner designed to hold the tube in the predetermined configuration, and (c) a plurality of snippets connected at predetermined locations to the rafter, the snippets extending away from a bottom surface of the rafter, and configured to (i) hold the rafter away from the substrate to allow flow of water and debris along the substrate without interference from the rafter, and (ii) allow relative movement of the rafter and tube relative to the snippets during expansion and contraction of the tube structure.

Abstract: A tube structure, and a method for assembling the tube structure, is provided, that is particularly useful in a solar heating system. The tube structure comprises, (a) a tube formed into a predetermined (e.g. coiled) configuration, (b) at least one rafter which engages the tube in a manner designed to hold the tube in the predetermined configuration, and (c) a plurality of snippets connected at predetermined locations to the rafter, the snippets extending away from a_bottom surface of the rafter, and configured to (i) hold the rafter away from the substrate to allow flow of water and debris along the substrate without interference from the rafter, and (ii) allow relative movement of the rafter and tube relative to the snippets during expansion and contraction of the tube structure.