摘要:
An x-ray imaging system (10), such as a X-ray computerised tomographic system, may acquire a series of radiographs at different detector positions along a first translation axis or a second translation axis parallel to orientation directions of detector pixels of a radiation detector (14). In a first embodiment, the different detector positions may be separated by a distance less than a linear size of the radiation detector (14) along the first translation axis or the second translation axis, respectively. The radiographs may be assembled into a radiograph larger than each radiograph in the series of radiographs, resulting in image stitching. In a second embodiment, the different detector positions may be separated by a distance less than a pixel size of the radiation detector (14), also referred as sub-pixel shifting of the detector. The radiographs may be assembled to form a radiograph with a higher resolution than the acquired radiographs, resulting in superresolution.
摘要:
An electron energy beam (28) discontinuously scans a sample (32) and at each scan position produces a thermal wave in the sample, there being infrared radiation emitted from the thermal wave. All of the infrared radiation emitted from the heated areas of the sample is collected by an ellipsoidal collector (34) and directed by reflection to an infrared detector (44), the sample and detector being at the foci of the collector (34), to give a two-dimensional image of the sample. A computer system (52) is used to control data acquisition, storage, processing and image display, and also modulation and scanning of the beam (28). Surface, on the surface, and sub-surface structure of the sample can be detected, for example to reveal defects, or surface particles.
摘要:
Embodiments of methods and apparatus are disclosed for obtaining a phase-contrast digital imaging system and methods for same that can include an x-ray source for radiographic imaging; a beam shaping assembly, an x-ray grating interferometer including a phase grating and an analyzer grating; and an x-ray detector; where the source grating, the phase grating, and the analyzer grating are detuned and a plurality of uncorrelated reference images are obtained for use in imaging processing with the detuned system.
摘要:
A multi-beam apparatus for inspecting or processing a sample (232) with a multitude of focused beams, the apparatus equipped to scan a multitude of N beams (240-n) over the sample, the apparatus equipped with a multitude of M detectors (234-m) for detecting secondary radiation emitted by the sample when said sample is irradiated by the multitude of beams, each of the detectors capable of outputting a detector signal representing the intensity of the secondary radiation detected by the detector, , in working, each detector signal comprising information caused by multiple beams, the information caused by one beam thus spread over multiple detectors, the apparatus equipped with a programmable controller (236) for processing the multitude of detector signals to a multitude of output signals, using weight factors so that each output signal represents information caused by a single beam, characterized in that the weight factors are dynamic weight factors depending on the scan position of the beams with respect to the detectors and the distance between sample and detectors. The weight factors describe the contribution of each beam to each detector. The invention is based on the insight that when scanning the beams over the sample, the position of the position where the secondary radiation is formed (the impact position) changes. Therefore the weight factors should be a function of the scan position. Also the distance between sample and detector (the working distance) has a similar effect on the weight factors It is noted that, as the position of the impact is known at all times the weight factors can be a known function of the scan position, working distance and, if applicable, the beam energies.
摘要:
An x-ray imaging system (10), such as a X-ray computerised tomographic system, may acquire a series of radiographs at different detector positions along a first translation axis or a second translation axis parallel to orientation directions of detector pixels of a radiation detector (14). In a first embodiment, the different detector positions may be separated by a distance less than a linear size of the radiation detector (14) along the first translation axis or the second translation axis, respectively. The radiographs may be assembled into a radiograph larger than each radiograph in the series of radiographs, resulting in image stitching. In a second embodiment, the different detector positions may be separated by a distance less than a pixel size of the radiation detector (14), also referred as sub-pixel shifting of the detector. The radiographs may be assembled to form a radiograph with a higher resolution than the acquired radiographs, resulting in superresolution.
摘要:
The invention relates to a multi-beam apparatus for inspecting a sample (232) with a multitude of focused beams, the apparatus equipped to scan a multitude of N beams (240-n) over the sample, the apparatus equipped with a multitude of M detectors (234-m) for detecting secondary radiation emitted by the sample when said sample is irradiated by the multitude of beams, each of the detectors capable of outputting a detector signal representing the intensity of the secondary radiation detected by the detector, characterized in that, in working, each detector signal comprises information caused by multiple beams, the information caused by one beam thus spread over multiple detectors, the apparatus equipped with a programmable controller (236) for processing the multitude of detector signals to a multitude of output signals, the controller processing the multitude of detector signals so that each output signal represents information caused by a single beam.