A bone density measuring apparatus and a bone density imaging method capable of improving the accuracy of a bone density analysis are provided. In a state in which no subject is present, a detector detects X-rays emitted from an X-ray tube under a high tube voltage X-ray condition/a low tube voltage X-ray condition and a first gain correction map/a second gain correction map is generated (S1, S2). A detector detects the X-rays emitted from an X-ray tube and transmitted through a subject under a high tube voltage X-ray condition/a low tube voltage X-ray condition, and a high voltage image/a low voltage image captured by the detector is generated (S3). By performing a gain correction of the high voltage image using the first gain correction map, performing a gain correction of the low voltage image using the second gain correction map (S4), and performing a subtraction of the high voltage image after the gain correction and the low voltage image after the gain correction (S5), the accuracy of the bone density analysis can be improved.

A radiography system includes an image former, a first determiner, and an operation controller. The image former performs serial radiography of repeatedly generating a frame that constitutes a video. The first determiner determines whether a next test action is the serial radiography. The operation controller makes the image former begin turning a switch element on/off in a same manner as a manner in the serial radiography before start of the next test action in a case where the first determiner determines that the next test action is the serial radiography.

A method for determining a correction profile of an imaging device may include obtaining first data relating to the imaging device; comparing the first data and a first condition; obtaining, based on the comparison, a first correction profile relating to the imaging device; and calibrating, based on the first correction profile, the imaging device.

A method and apparatus for diagnosing and/or calibrating underperforming pixels in detectors in a small pixelated photon counting CT system utilizes a series of tests on image data acquired in-situ as part of a series of calibration scans in the CT system. Tests are performed on the acquired data to determine the existence of underperforming pixels within the detectors such that the information acquired by those pixels can be replaced by alternate data from surrounding pixels (e.g. by interpolation). The underperforming pixels are stored in “bad” pixel tables and may be specific to a type of image (e.g., spectral or counting) and a specific protocol.

A photon counting computed tomography (CT) method including, but not limited to, receiving a first forward model including a set of first parameters and a set of second parameters corresponding to a plurality of materials and path lengths by scanning a slab at plural tube voltages and plural tube currents of an X-ray tube; evaluating an image quality of a material decomposition image reconstructed by the set of first parameters and the set of second parameters; and updating at least one second parameters from the set of second parameters if the image quality of the material decomposition image does not satisfy a predetermined threshold, wherein the update of the at least one second parameter from the set of second parameters is achieved by updating the at least one second parameter from the set of second parameters to an energy dependent parameter from a constant value. Processing circuitry that is part of a photon counting computed tomography (CT) can implement the method.

An X-ray imaging apparatus includes an X-ray source, an X-ray imaging panel, and a controller. The controller includes an image processing unit that generates an inspection image in accordance with a data signal read from a thin-film transistor with the thin-film transistor supplied with a gate signal, a detection control unit that detects a dark-spot pixel from the inspection image, and a threshold correction unit that applies, to a gate of the thin-film transistor corresponding to the dark-spot pixel, a positive shift voltage that raises a gate-off threshold voltage of the thin-film transistor.

A method and a system for providing calibration for a polychromatic photon counting detector forward counting model. Measurements with multiple materials and known path lengths are used to calibrate the photon counting detector counting response of the forward model. The flux independent weighted bin response function is estimated using the expectation maximization method, and then used to estimate the pileup correction terms at plural tube voltage settings for each detector pixel. The beam hardening corrections are then applied to the measured projection data sinogram, and the corrected sinogram is reconstructed to the counting image at the selected single energy.

The disclosure relates to a system and method for tracking and correcting X-ray focus positions in a computed tomography (CT) device. The device may include an X-ray tube, a collimator, and a detector. The collimator may include an opening, wherein the collimator has a width in a first direction and a length in a second direction. The opening may have an opening width in the width direction of the collimator, and an opening at at least one end of the collimator in the second direction may have an opening width smaller than that of an opening within the middle section of the collimator.

A radiation imaging apparatus comprises a generating unit configured to generate a material characteristic image with respect to a plurality of materials included in a radiation image that has been captured using different radiation energies; and a reconstructing unit configured to set different radiation energies for the respective plurality of materials, and to generate a reconstructed image based on monochromatic radiation images of the respective materials, the monochromatic radiation images being based on the different radiation energies.

Various methods and systems are provided for calibrating a camera-based feature detection system for an x-ray system having a support surface, and a gantry operably connected to the support surface and a light source disposed on the gantry, where the gantry defines a system referential. The x-ray system includes a camera spaced from the gantry and operably connected to a calibration system, the camera defining a camera referential within which the support surface and gantry are positioned. The calibration system registers the camera referential to the system referential by operating the light source to position an indication on the support surface and by obtaining a number of camera images of the indication on the support surface and corresponding indication location in the system referential.