Abstract: An optical measurement device with a transparent cylindrical measurement cuvette, which defines an axial symmetrical axis and contains the fluid sample, an optical measurement arrangement which quantitatively determines the optical property of the fluid sample in the measurement cuvette, and a mechanical cleaning arrangement is described. The cleaning arrangement comprises an external magnetic working platform, which is arranged coaxially to the symmetrical axis, is slidable in a translatory manner parallel to the symmetrical axis, is rotatable about the symmetrical axis, encloses the cylindrical measurement cuvette externally in an annular manner, and has at least one translatory magnet element and at least one rotary magnet element, and an internal magnetic cleaning unit, which is arranged within the measurement cuvette and is slidable in a translatory manner, has a cleaning body, has at least one translatory magnet element, and has at least one rotary magnet element.

Abstract: An optical measurement device with a transparent cylindrical measurement cuvette, which defines an axial symmetrical axis and contains the fluid sample, an optical measurement arrangement which quantitatively determines the optical property of the fluid sample in the measurement cuvette, and a mechanical cleaning arrangement is described. The cleaning arrangement comprises an external magnetic working platform, which is arranged coaxially to the symmetrical axis, is slidable in a translatory manner parallel to the symmetrical axis, is rotatable about the symmetrical axis, encloses the cylindrical measurement cuvette externally in an annular manner, and has at least one translatory magnet element and at least one rotary magnet element, and an internal magnetic cleaning unit, which is arranged within the measurement cuvette and is slidable in a translatory manner, has a cleaning body, has at least one translatory magnet element, and has at least one rotary magnet element.

Abstract: The invention relates to a method for preventing contamination on the surfaces of optical elements comprising a multi-layer system, during the exposure thereof to radiation at signal wave lengths in an evacuated closed system comprising a residual gas atmosphere, whereby the photocurrent generated by means of photo emission from the radiated surface of the multi-layer system is measured. The photocurrent is used to regulate the gas composition of the residual gas. The gas composition is altered according to at least one lower and one upper threshold value of the photocurrent. The invention also relates to a device for regulating the contamination on the surface of at least one optical element during exposure and an EUV-lithographic device and a method for cleaning the surfaces of the optical elements contaminated by carbon.

Abstract: In order to reduce contamination of optical elements which comprise a multilayer system on a substrate, it is proposed that the layer material and/or the layer thickness of at least one layer of the multilayer system are/is selected such that the standing wave which forms during reflection of the irradiated operating wavelength, forms a node of the electrical field intensity (node condition) in the area of the free interface of the multilayer system. Furthermore, a method for determining a design of a multilayer system, as well as a manufacturing process and a lithography apparatus are described.

Abstract: The invention relates to a method for preventing contamination on the surfaces of optical elements comprising a multi-layer system, during the exposure thereof to radiation at signal wave lengths in an evacuated closed system comprising a residual gas atmosphere, whereby the photocurrent generated by means of photo emission from the radiated surface of the multi-layer system is measured. The photocurrent is used to regulate the gas composition of the residual gas. The gas composition is altered according to at least one lower and one upper threshold value of the photocurrent. The invention also relates to a device for regulating the contamination on the surface of at least one optical element during exposure and an EUV-lithographic device and a method for cleaning the surfaces of the optical elements contaminated by carbon.

Abstract: The invention relates to a method for preventing contamination on the surfaces of optical elements comprising a multi-layer system, during the exposure thereof to radiation at signal wave lengths in an evacuated closed system comprising a residual gas atmosphere, whereby the photocurrent generated by means of photo emission from the radiated surface of the multi-layer system is measured. The photocurrent is used to regulate the gas composition of the residual gas. The gas composition is altered according to at least one lower and one upper threshold value of the photocurrent. The invention also relates to a device for regulating the contamination on the surface of at least one optical element during exposure and an EUV-lithographic device and a method for cleaning the surfaces of the optical elements contaminated by carbon.

Abstract: The invention relates to a method for preventing contamination on the surfaces of optical elements comprising a multi-layer system, during the exposure thereof to radiation at signal wave lengths in an evacuated closed system comprising a residual gas atmosphere, whereby the photocurrent generated by means of photo emission from the radiated surface of the multi-layer system is measured. The photocurrent is used to regulate the gas composition of the residual gas. The gas composition is altered according to at least one lower and one upper threshold value of the photocurrent. The invention also relates to a device for regulating the contamination on the surface of at least one optical element during exposure and an EUV-lithographic device and a method for cleaning the surfaces of the optical elements contaminated by carbon.