A device for calibrating an in-line sensor is disclosed, including a housing having a first aperture and a second aperture arranged along an optical path extending through the housing, a first filter and a second filter disposed within the housing such that the filters are moveable from an operating position to a calibration position. In the calibration position the filters are arranged in the optical path and the housing includes a connection adjacent each of the first aperture and the second aperture, the connection structured to enable the housing to be reversibly attached to a flow cell, a detector and a light source of an in-line sensor.

A method of patterning lithographic substrates, the method including using a free electron laser to generate EUV radiation and delivering the EUV radiation to a lithographic apparatus which projects the EUV radiation onto lithographic substrates, wherein the method further includes reducing fluctuations in the power of EUV radiation delivered to the lithographic substrates by using a feedback-based control loop to monitor the free electron laser and adjust operation of the free electron laser accordingly.

Various embodiments of a light detection device and a system that utilizes such device are disclosed. In one or more embodiments, the light detection device can include a housing that includes a port disposed in a top surface, a receptacle disposed within the housing and adapted to receive a sample, a detector disposed within the housing along an optical axis and including an input surface having an active area, and a reflector disposed within the housing along the optical axis between the receptacle and the input surface of the detector. The reflector can include an input aperture disposed adjacent the receptacle, an output aperture disposed adjacent the input surface of the detector, and a reflective surface that extends between the input aperture and the output aperture.

A photometer (100), which includes a light source (1), an optical element (30) disposed on an optical path P of light emitted from the light source (1), and a detector (5), includes: an attenuating filter (24a) that is disposed on the optical path P and between the light source (1) and the optical element (30), and blocks a portion of the light emitted from the light source (1) and allows the rest of the light to be transmitted through the attenuating filter (24a); and a state monitoring unit (83) that monitors whether or not the light source (1) and the optical element (30) are in a stable state by monitoring light that has been transmitted through the attenuating filter (24a) on the side of a stage subsequent to the optical element (30).

The present disclosure envisages an optical attenuator assembly which is compact and cost effective. The optical attenuator assembly comprises a protective layer, an attenuation layer, and a vinyl layer. The protective layer has a cavity configured thereon to facilitate reception of a sensor mounted on a base. The attenuation layer is deposited on the protective layer, and is configured to attenuate the intensity of incident light rays. The attenuation layer is further configured to provide attenuated light rays to the sensor. The vinyl layer is deposited on the attenuation layer. The vinyl layer has a window configured thereon to facilitate the light rays to incident on the attenuation layer, and is further configured to limit the angle of incident of the light ray with respect to the sensor.

A metrology system includes an illumination source to generate an illumination beam, a multi-channel spectral filter, a focusing element to direct illumination from the single optical column to a sample, and at least one detector to capture the illumination collected from the sample. The multi-channel spectral filter includes two or more filtering channels having two or more channel beam paths. The two or more filtering channels filter illumination propagating along the two or more channel beam paths based on two or more spectral transmissivity distributions. The multi-channel spectral filter further includes a channel selector to direct at least a portion of the illumination beam into at least one selected filtering channel to filter the illumination beam. The multi-channel spectral filter further includes at least one beam combiner to combine illumination from the two or more filtering channels to a single optical column.

An electronic device may have a display with a cover layer. An ambient light sensor may be aligned with an ambient light sensor window formed from an opening in a masking layer on the cover layer in an inactive portion of the display. To help mask the ambient light sensor window from view, the ambient light sensor window may be provided with a black coating that matches the appearance of surrounding masking layer material while allowing light to reach the ambient light sensor. The black coating may be formed from a black physical vapor deposition thin-film inorganic layer with a high index of refraction. An antireflection layer formed from a stack of dielectric layers may be interposed between the black thin-film inorganic layer and the display cover layer.

A test device includes: a support that supports a light emitting device subject to a test; a light waveguide that guides light output from the light emitting device supported by the support; a light diffuser plate that diffuses light output from the light waveguide; and a light receiving device that receives light diffused by the light diffuser plate. The test device may further include a constant-temperature device that houses the support and the light emitting device supported by the support and control a temperature of the light emitting device. The light receiving device may be provided outside the constant-temperature device, and the light waveguide may guide light from inside the constant-temperature device to a space outside the constant-temperature device.

A signal barrier for a sensor device can include at least one wall that forms an inner space, wherein the at least one wall comprises a material for reducing an amount of a signal from entering the inner space, wherein the at least one wall is configured to be disposed adjacent to a transceiver element of the sensor device, wherein the transceiver element is directed to the inner space.

A device for calibrating an in-line sensor is disclosed, including a housing having a first aperture and a second aperture arranged along an optical path extending through the housing, a first filter and a second filter disposed within the housing such that the filters are moveable from an operating position to a calibration position. In the calibration position the filters are arranged in the optical path and the housing includes a connection adjacent each of the first aperture and the second aperture, the connection structured to enable the housing to be reversibly attached to a flow cell, a detector and a light source of an in-line sensor.