A dark-field optical system may include a rotational objective lens assembly with a dark-field objective lens to collect light from a sample within a collection numerical aperture, where the dark-field objective lens includes an entrance aperture and an exit aperture at symmetrically-opposed azimuth angles with respect to an optical axis, a rotational bearing to allow rotation of at least a part of the dark-field objective lens including the entrance aperture and the exit aperture around the optical axis, and a rotational driver to control a rotational angle of the entrance aperture. The system may also include a multi-angle illumination sub-system to illuminate the sample with an illumination beam through the entrance aperture at two or more illumination azimuth angles, where an azimuth angle of the illumination beam on the sample is selectable by rotating the objective lens to any of the two or more illumination azimuth angles.

A device for dark-field optical inspection of a substrate comprises: a light source for generating an incident beam that is projected onto an inspection zone of the substrate and that is capable of being reflected in the form of diffuse radiation; at least one first and one second collecting device; and a reflecting device for directing at least a portion of the diffuse radiation originating from a focal point of collection coincident with the inspection zone in the direction of the collecting devices, with a first and second reflective zone from which a first portion of the diffuse radiation is directed toward a first focal point, which is optically conjugated with the focal point of collection, and a second portion of the diffuse radiation is reflected toward a second focal point, which is optically conjugated with the collection focal point and distinct from the first focal point of detection.

A surface inspection system for inspecting the surface of sheet elements present in an inspection area: The system includes two light sources arranged adjacent each other on opposite sides of an illumination plane, and a camera for capturing line images of the inspection area along a viewing plane. The illumination plane and the viewing plane are arranged on opposite sides of a median plane perpendicular to an inspection plane. The angle between the illumination plane and the median plane is the same as the angle between the viewing plane and the median plane. In a method of using the system, the first light source illuminates the sheet element before the second light sources does. An image evaluation unit compares the captured line images with each other.

The present disclosure featured compositions and methods related to the detection and molecular profiling of extracellular vesicles using optical probes, dual imaging approaches, and computationally programing-based image analysis methods. These compositions and methods leverage the unique optoelectrical properties of quantum dots, fluorescently labeled nanoparticles, and gold nanoparticles, which allow reliable, real-time detection of extracellular vesicles and vesicle surface bound or lumenal molecules at single vesicle level.

Methods of performing metrology. In one arrangement a substrate has a layer. The layer comprises a two-dimensional material. A target portion of the layer is illuminated with a beam of radiation and a distribution of radiation in a pupil plane is detected to obtain measurement data. The measurement data is processed to obtain metrology information about the target portion of the layer. The illuminating, detecting and processing are performed for plural different target portions of the layer to obtain metrology information for the plural target portions of the layer.

Methods for detecting areas of localized tilt on a sample using imaging reflectometry measurements include obtaining a first image without blocking any light reflected from the sample and obtaining a second image while blocking some light reflected from the sample at the aperture plane. The areas of localized tilt are detected by comparing first reflectance intensity values of pixels in the first image with second reflectance intensity values of corresponding pixels in the second image.

The invention relates to a method for optically testing containers, in which a container (10) is conveyed by means of a transport device (30), whereby an image of a side wall surface of the container (10) is generated by means of an inspection unit (40) comprising a camera unit (20) and an illumination unit (34). An inspection volume (24) is spanned by several correspondingly arranged inspection units (40), in which an image of the entire side wall surface (26) of the container (10) is generated in a transmitted light method, an incident light method and/or a dark-field method.

Methods for detecting areas of localized tilt on a sample using imaging reflectometry measurements include obtaining a first image without blocking any light reflected from the sample and obtaining a second image while blocking some light reflected from the sample at the aperture plane. The areas of localized tilt are detected by comparing first reflectance intensity values of pixels in the first image with second reflectance intensity values of corresponding pixels in the second image.

An overlay metrology system may include an illumination sub-system to sequentially illuminate an overlay target with a first illumination lobe and a second illumination lobe opposite the first illumination lobe, where the overlay target includes grating-over-grating features formed from periodic structures on a first sample layer and a second sample layer. The system may further include an imaging sub-system to generate a first image and a second image of the overlay target. The first image includes an unresolved image of the grating-over-grating structures formed from a single non-zero diffraction order of the first illumination lobe. The second image includes an unresolved image of the one or more grating-over-grating structures formed from a single non-zero diffraction order of the second illumination lobe. The system may further include a controller to determine an overlay error between the first layer and the second layer based on the first image and the second image.

An inspection system may include an illumination source to generate an illumination beam, illumination optics to direct the illumination beam to a sample at an off-axis angle along an illumination direction, and collection optics to collect scattered light from the sample in a dark-field mode, where the scattered light from the sample includes surface haze associated with light scattered from a surface of the sample, and where at least a at least a portion of the surface haze has elliptical polarizations. The system may further include pupil-plane optics to convert the polarizations of the surface haze across the pupil to linear polarization that is aligned parallel to a selected haze orientation direction. The system may include a linear polarizer to reject the surface haze aligned parallel to this haze orientation direction and a detector to generate a dark-field image of the sample based on light passed by the linear polarizer.