Abstract: A method of producing photonic crystal fibers (PCFs) is disclosed, the method includes: 1) obtaining an intermediate PCF having an initial outer fiber diameter of less than 1 mm; and 2) elongating the intermediate PCF so as to controllably reduce at least one dimension of the intermediate PCF.

Abstract: Disclosed is a pupil shaping arrangement for obtaining a defined pupil intensity profile for a metrology illumination beam configured for use in a metrology application. The pupil shaping arrangement comprises an engineered diffuser (ED) having a defined far-field profile configured to impose said defined pupil intensity profile on said metrology illumination beam. The pupil shaping arrangement may further comprise a multimode fiber (MMF) and be configured to reduce spatial coherence of coherent radiation.

Abstract: Disclosed is a pupil shaping arrangement for obtaining a defined pupil intensity profile for a metrology illumination beam configured for use in a metrology application. The pupil shaping arrangement comprises an engineered diffuser (ED) having a defined far-field profile configured to impose said defined pupil intensity profile on said metrology illumination beam. The pupil shaping arrangement may further comprise a multimode fiber (MMF) and be configured to reduce spatial coherence of coherent radiation.

Abstract: A broadband radiation source device configured for generating a broadband output radiation upon receiving pump radiation, the device including: a hollow-core photonic crystal fiber (HC-PCF) including at least one structurally varied portion having at least one structural parameter of the HC-PCF varied with respect to one or more main portions of the HC-PCF, wherein the at least one structurally varied portion includes at least a structurally varied portion located downstream of a position along the length of the HC-PCF where the pump radiation will be spectrally expanded by a modulation instability dominated nonlinear optical process, and wherein the at least one structurally varied portion is configured and located such that the broadband output radiation includes wavelengths in the ultraviolet region.

Abstract: Optical components and methods of manufacture thereof. A first optical component has a hollow-core photonic crystal fiber includes internal capillaries for guiding radiation and an outer capillary sheathing the internal capillaries; and at least an output end section having a larger inner cross-sectional dimension over at least a portion of the output end section than an inner cross-sectional dimension of the outer capillary along a central portion of the hollow-core photonic crystal fiber prior to the output end section. A second optical component includes a hollow-core photonic crystal fiber and a sleeve arrangement.

Abstract: A broadband radiation source device configured for generating a broadband output radiation upon receiving pump radiation, the device including: a hollow-core photonic crystal fiber (HC-PCF) including at least one structurally varied portion having at least one structural parameter of the HC-PCF varied with respect to one or more main portions of the HC-PCF, wherein the at least one structurally varied portion includes at least a structurally varied portion located downstream of a position along the length of the HC-PCF where the pump radiation will be spectrally expanded by a modulation instability dominated nonlinear optical process, and wherein the at least one structurally varied portion is configured and located such that the broadband output radiation includes wavelengths in the ultraviolet region.

Abstract: Optical components and methods of manufacture thereof. A first optical component has a hollow-core photonic crystal fiber includes internal capillaries for guiding radiation and an outer capillary sheathing the internal capillaries; and at least an output end section having a larger inner cross-sectional dimension over at least a portion of the output end section than an inner cross-sectional dimension of the outer capillary along a central portion of the hollow-core photonic crystal fiber prior to the output end section. A second optical component includes a hollow-core photonic crystal fiber and a sleeve arrangement.

Abstract: A broadband radiation source device configured for generating a broadband output radiation upon receiving pump radiation, the device including: a hollow-core photonic crystal fiber (HC-PCF) including at least one structurally varied portion having at least one structural parameter of the HC-PCF varied with respect to one or more main portions of the HC-PCF, wherein the at least one structurally varied portion includes at least a structurally varied portion located downstream of a position along the length of the HC-PCF where the pump radiation will be spectrally expanded by a modulation instability dominated nonlinear optical process, and wherein the at least one structurally varied portion is configured and located such that the broadband output radiation includes wavelengths in the ultraviolet region.

Abstract: Optical components and methods of manufacture thereof. A first optical component has a hollow-core photonic crystal fiber includes internal capillaries for guiding radiation and an outer capillary sheathing the internal capillaries; and at least an output end section having a larger inner cross-sectional dimension over at least a portion of the output end section than an inner cross-sectional dimension of the outer capillary along a central portion of the hollow-core photonic crystal fiber prior to the output end section. A second optical component includes a hollow-core photonic crystal fiber and a sleeve arrangement.

Abstract: A metrology apparatus is disclosed that has an optical system to focus radiation onto a structure and directs redirected radiation from the structure to a detection system. The optical system applies a plurality of different offsets of an optical characteristic to radiation before and/or after redirected by the structure, such that a corresponding plurality of different offsets are provided to redirected radiation derived from a first point of a pupil plane field distribution relative to redirected radiation derived from a second point of the pupil plane field distribution. The detection system detects a corresponding plurality of radiation intensities resulting from interference between the redirected radiation derived from the first point of the pupil plane field distribution and the redirected radiation derived from the second point of the pupil plane field distribution. Each radiation intensity corresponds to a different one of the plurality of different offsets.

Abstract: A metrology apparatus is disclosed that measures a structure formed on a substrate to determine a parameter of interest. The apparatus comprises an optical system configured to focus radiation onto the structure and direct radiation after reflection from the structure onto a detector, wherein: the optical system is configured such that the detector detects a radiation intensity resulting from interference between radiation from at least two different points in a pupil plane field distribution, wherein the interference is such that a component of the detected radiation intensity containing information about the parameter of interest is enhanced relative to one or more other components of the detected radiation intensity.

Abstract: A metrology apparatus is disclosed that has an optical system to focus radiation onto a structure and directs redirected radiation from the structure to a detection system. The optical system applies a plurality of different offsets of an optical characteristic to radiation before and/or after redirected by the structure, such that a corresponding plurality of different offsets are provided to redirected radiation derived from a first point of a pupil plane field distribution relative to redirected radiation derived from a second point of the pupil plane field distribution. The detection system detects a corresponding plurality of radiation intensities resulting from interference between the redirected radiation derived from the first point of the pupil plane field distribution and the redirected radiation derived from the second point of the pupil plane field distribution. Each radiation intensity corresponds to a different one of the plurality of different offsets.

Abstract: A metrology apparatus is disclosed that has an optical system to focus radiation onto a structure and directs redirected radiation from the structure to a detection system. The optical system applies a plurality of different offsets of an optical characteristic to radiation before and/or after redirected by the structure, such that a corresponding plurality of different offsets are provided to redirected radiation derived from a first point of a pupil plane field distribution relative to redirected radiation derived from a second point of the pupil plane field distribution. The detection system detects a corresponding plurality of radiation intensities resulting from interference between the redirected radiation derived from the first point of the pupil plane field distribution and the redirected radiation derived from the second point of the pupil plane field distribution. Each radiation intensity corresponds to a different one of the plurality of different offsets.

Abstract: A metrology apparatus is disclosed that has an optical system to focus radiation onto a structure and directs redirected radiation from the structure to a detection system. The optical system applies a plurality of different offsets of an optical characteristic to radiation before and/or after redirected by the structure, such that a corresponding plurality of different offsets are provided to redirected radiation derived from a first point of a pupil plane field distribution relative to redirected radiation derived from a second point of the pupil plane field distribution. The detection system detects a corresponding plurality of radiation intensities resulting from interference between the redirected radiation derived from the first point of the pupil plane field distribution and the redirected radiation derived from the second point of the pupil plane field distribution. Each radiation intensity corresponds to a different one of the plurality of different offsets.

Abstract: A metrology apparatus is disclosed that measures a structure formed on a substrate to determine a parameter of interest. The apparatus comprises an optical system configured to focus radiation onto the structure and direct radiation after reflection from the structure onto a detector, wherein: the optical system is configured such that the detector detects a radiation intensity resulting from interference between radiation from at least two different points in a pupil plane field distribution, wherein the interference is such that a component of the detected radiation intensity containing information about the parameter of interest is enhanced relative to one or more other components of the detected radiation intensity.