The present invention is directed to spatial-spectral filtering for multi-material CT decomposition. The invention includes a specialized filter that spectrally shapes an x-ray beam into a number of beamlets with different spectra. The filter allows decomposition of an object/anatomy into different material categories (including different biological types: muscle, fat, etc. or exogenous contrast agents that have been introduced: e.g iodine, gadolinium, etc.). The x-ray beam is spectrally modulated across the face of the detector using a repeating pattern of filter materials. Such spatial-spectral filters allow for collection of many different spectral channels using “source-side” control. However, in contrast to other spectral techniques that provide mathematically complete projection data, spatial-spectral filtered data is sparse in each spectral channel—making traditional projection-domain or image-domain material decomposition difficult to apply. Therefore, the present invention uses model-based material decomposition, which combines reconstruction and multi-material decomposition, and permits arbitrary spectral, spatial, and angular sampling patterns.

The present invention relates to a grating for X-ray phase contrast and/or dark-field imaging. It is described to form a photo-resist layer on a surface of a substrate. The photo-resist layer is illuminated with radiation using a mask representing a desired grating structure. The photo-resist layer is etched to remove parts of the photo-resist layer, to leave a plurality of trenches that are laterally spaced from one across the surface of the substrate. A plurality of material layers are formed on the surface of the substrate. Each layer is formed in a trench. A material layer comprises a plurality of materials, wherein the plurality of materials are formed one on top of the other in a direction perpendicular to the surface of the substrate. The plurality of materials comprises at least one material that has a k-edge absorption energy that is higher than the k-edge absorption energy of Gold and the plurality of materials comprises Gold.

A method is for controlling an x-ray imaging device, in particular a computed tomography device. The x-ray imaging device includes an x-ray source and a photon counting detector as an x-ray detector. The methods includes, for an image acquisition process of a patient: determining at least one input parameter relating to at least one of an attenuation property of the patient and a purpose of the image acquisition; at least one of determining or adapting at least one operation parameter of the x-ray detector, dependent upon the at least one input parameter determined; and performing the image acquisition using the at least one operation parameter determined or adapted.

Systems and method for performing X-ray computed tomography (CT) that can improve spectral separation and decrease motion artifacts without increasing radiation dose are provided. The systems and method can be used with either a kVp-switching source or a single-kVp source. When used with a kVp-switching source, an absorption grating and a filter grating can be disposed between the X-ray source and the sample to be imaged. Relative motion of the filter and absorption gratings can by synchronized to the kVp switching frequency of the X-ray source. When used with a single-kVp source, a combination of absorption and filter gratings can be used and can be driven in an oscillation movement that is optimized for a single-kVp X-ray source. With a single-kVp source, the absorption grating can also be omitted and the filter grating can remain stationary.

Some embodiments include an x-ray system, comprising: an x-ray imager including a plurality of imaging layers; an x-ray source configured to generate an x-ray beam; and an x-ray prefilter; wherein: the x-ray prefilter is configured to adjust an energy spectrum of the x-ray beam to create or decrease a level of x-ray fluence of a local minimum between two of a plurality of local maximums.

A method for generating an x-ray image in color includes selecting three-sets of x-ray images in gray scale acquired with x-rays having different energy spectra, assigning basic colors RGB to the three-sets, and displaying the x-ray image in color with RGB signals generated. A system for generating an x-ray image in color includes an x-ray generator configured to generate at least three sets of x-rays with different energy spectra, an x-ray detector, a controller, a computer, and a color display. The computer is configured to generate three sets of x-ray images from output data of the x-ray detector acquired for x-rays with different energy spectra, assign RGB and display an x-ray image in color. A non-transitory computer readable medium stores an instruction, when the instruction is executed by a processor, cause the processor to perform the method for generating an x-ray image in color.

Methods and systems are provided for cross calibration between two or more dual energy x-ray absorptiometry (DXA) systems. In one example, a calibration phantom is scanned along with a patient during a scanning sequence, with a first system, to obtain one or more coefficients that map pixel values retrieved from a phantom image from the phantom scan to image pixel values in the reconstructed patient image from the patient scan. The one or more coefficients may be utilized to adjust and/or compare BMD values of the patient obtained when the patient is scanned with a different system utilizing a phantom with similar composition and parameters as the calibration phantom.

Disclosed herein is a dual energy X-ray imaging apparatus. The dual energy X-ray imaging apparatus includes: an X-ray generator configured to generate a predetermined dose of X-rays; an X-ray detector configured to detect the X-rays received from the X-ray generator; an X-ray filter located between the X-ray generator and the X-ray detector, and configured to filter out part of the generated X-rays so that X-rays of two dose types reach the X-ray detector; and a medical image processing unit configured to generate medical images corresponding to the two dose types recognized by the X-ray detector.

An X-ray imaging apparatus according to an embodiment of the present disclosure includes an X-ray tube, a photon counting X-ray detector, and a filter unit. A generating unit of the X-ray tube is configured to generate X-rays. The photon counting X-ray detector is configured to count photons contained in the X-rays. The filter unit is provided between the X-ray tube and the photon counting X-ray detector. The filter unit includes a first filter and a second filter. The first filter is configured to shape a spectrum of the X-rays. The second filter is configured to generate X-ray fluorescence on the basis of X-rays related to a spectrum resulting from the shaping by the first filter.

The present invention relates to a grating for X-ray phase contrast and/or dark-field imaging. It is described to form a photo-resist layer on a surface of a substrate. The photo-resist layer is illuminated with radiation using a mask representing a desired grating structure. The photo-resist layer is etched to remove parts of the photo-resist layer, to leave a plurality of trenches that are laterally spaced from one across the surface of the substrate. A plurality of material layers are formed on the surface of the substrate. Each layer is formed in a trench. A material layer comprises a plurality of materials, wherein the plurality of materials are formed one on top of the other in a direction perpendicular to the surface of the substrate. The plurality of materials comprises at least one material that has a k-edge absorption energy that is higher than the k-edge absorption energy of Gold and the plurality of materials comprises Gold.