409 results about "Phase grating" patented technology

A differential phase-contrast X-ray imaging system is provided. Along the direction of X-ray propagation, the basic components are X-ray tube, filter, object platform, X-ray phase grating, and X-ray detector. The system provides: 1) X-ray beam from parallel-arranged source array with good coherence, high energy, and wider angles of divergence with 30-50 degree. 2) The novel X-ray detector adopted in present invention plays dual roles of conventional analyzer grating and conventional detector. The basic structure of the detector includes a set of parallel-arranged linear array X-ray scintillator screens, optical coupling system, an area array detector or parallel-arranged linear array X-ray photoconductive detector. In this case, relative parameters for scintillator screens or photoconductive detector correspond to phase grating and parallel-arranged line source array, which can provide the coherent X-rays with high energy.

A device for imaging an object, such as for breast imaging, includes a gantry frame having mounted thereon an x-ray source, a source grating, a holder or other place for the object to be imaged, a phase grating, an analyzer grating, and an x-ray detector. The device images objects by differential-phase-contrast cone-beam computed tomography. A hybrid system includes sources and detectors for both conventional and differential-phase-contrast computed tomography.

The present invention discloses an interferometer device and method. In embodiments, the device comprises an electromagnetic radiation source emitting radiation having a first mean wavelength λLE; a phase grating having a first aspect ratio; an absorption grating having a second aspect ratio; and a detector. The electromagnetic radiation source, the phase grating, the absorption grating and the detector are radiatively coupled with each other. The absorption grating is positioned between the detector and the phase grating; the electromagnetic radiation source is positioned in front of the source grating; and wherein the phase grating is designed such to cause a phase shift that is smaller than π on the emitted radiation. Additional and alternative embodiments are specified and claimed.

An x-ray CT system for x-ray phase contrast and / or x-ray dark field imaging has a grating interferometer that has a first grating structure that has a number of band-shaped x-ray emission maxima and minima arranged in parallel, the maxima and minima exhibiting a first grating period, a second band-shaped grating structure that produces, as a phase grating, a partial phase offset of x-ray radiation passing therethrough and that exhibits a second grating period, a third band-shaped grating structure with a third grating period with which relative phase shifts of adjacent x-rays and / or their scatter components are detected, and a device for value-based determination of the phase between adjacent x-rays and / or for value-based determination of the spatial intensity curve per detector element perpendicular to the bands of the grating structures. The third grating structure has a grating period that is larger by a factor of 2 to 5 than the grating period of the first grating structure.

The invention relates to a rotational X-ray device (100), for example a CT scanner, for generating phase contrast images of an object (1). In a particular embodiment of the device (100), a plurality of X-ray sources (11), an X-ray detector (30), and an analyzer grating (G2) are attached to a rotatable gantry (20), while a ring-shaped phase grating (G1) is stationary. The X-ray sources are disposed such that X-rays first pass an object under study before traversing the phase grating (G1) and subsequently the analyzer grating (G2). This is achieved by either shifting the X-ray sources axially with respect to the ring-shaped phase grating (G1) or by disposing the X-ray sources in the interior of the ring. Moreover, the phase grating (G1) and the analyzer (G2) shall have spatially varying relative phase (and / or periodicity), for example realized by line grids that are tilted with respect to each other. During the rotation of the gantry (20), the synchronized activation of X-ray sources (11) allows to generate projection images of an object (1) from the same viewing angle with different relative positions (and therefore phases) between the phase grating (G1) and the analyzer (G2).

In a method to determine phase and / or amplitude between interfering, adjacent x-ray beams in a detector pixel in a Talbot interferometer for projective and tomographical x-ray phase contrast imaging and / or x-ray dark field imaging, after an irradiation of the examination subject with at least two coherent or quasi-coherent x-rays, an interference of the at least two coherent or quasi-coherent x-rays with the aid of an irradiated phase grating is generated, and the variation of multiple intensity measurements in temporal succession after an analysis grating is determined in relation to known displacements of one of the gratings or of an x-ray source fashioned like a grating, positioned upstream in the beam path, relative to one of the gratings. The integrating intensity measurements ensue during a relative movement—thus not during the standstill—of one of the upstream gratings or of the x-ray source fashioned like a grating or of the examination subject, with known speed behavior over a final time interval of a final distance.

Embodiments of methods and apparatus are disclosed for obtaining a phase-contrast digital radiographic imaging system and methods for same that can include an x-ray source for radiographic imaging; a beam shaping assembly including a collimator and a source grating, an x-ray grating interferometer including a phase grating, and an analyzer grating; and an x-ray detector, where a single arrangement of the beam shaping assembly, the x-ray grating interferometer and a position of the detector is configured to provide spectral information (e.g. at least two images obtained at different relative beam energies).

To provide a phase grating capable of acquiring, in photographing of an X-ray phase contrast image by use of X-ray with two wavelengths, an X-ray phase contrast image by a phase grating in the same size as when a single wavelength is used, provided is a phase grating used when an X-ray is directed to take an X-ray phase contrast image, the phase grating including a periodic structure for generating a phase difference between an X-ray transmitted through the structure and an X-ray not transmitted through the structure. The periodic structure has different periods in a plurality of directions in a same surface.