G01T7/00

System and method for calibrating a PET scanner

A method and system for calibrating a PET scanner are described. The PET scanner may have a field of view (FOV) and multiple detector rings. A detector ring may have multiple detector units. A line of response (LOR) connecting a first detector unit and a second detector unit of the PET scanner may be determined. The LOR may correlate to coincidence events resulting from annihilation of positrons emitted by a radiation source. A first time of flight (TOF) of the LOR may be calculated based on the coincidence events. The position of the radiation source may be determined. A second TOF of the LOR may be calculated based on the position of the radiation source. A time offset may be calculated based on the first TOF and the second TOF. The first detector unit and the second detector unit may be calibrated based on the time offset.

GAMMA RAY DETECTION SYSTEM AND CALIBRATION METHOD THEREOF
20230146548 · 2023-05-11 ·

Gamma ray detection system (10) comprising a computation system including a signal processing and control system (30), a detection module assembly (13) including at least one detection module (14) configured for detecting gamma ray emissions from a target zone (4), each detection module comprising at least one scintillator plate (16) having a major surface (40a) oriented to generally face the target zone and lateral minor surfaces (40b) defining edges of the scintillator layer, and a plurality of photon detectors oupled to said at least one scintillator plate and connected to the signal processing and control system. The scintillator plate comprises a material having isotopes intrinsically emitting radiation causing intrinsic scintillation events in one or more scintillator plates having an intensity measurable by the photon detectors. The gamma ray detection system comprises a calibration module configured to execute a spatial calibration procedure based on measurements of a plurality of said intrinsic scintillation events output (37) by the photon detectors, the spatial calibration procedure for determining spatial positions of scintillating events in the scintillator plate as a function of the outputs of the photon detectors.

Method and system for evaluating the working condition of a detector

The disclosure relates to a system and method for evaluating and calibrating detector in a scanner, further evaluating and calibrating time information detected by at least one time-to-digital convertor.

Radiographic imaging device
11644430 · 2023-05-09 · ·

A high-sensitive phase imaging is achieved using a grating section without upsizing the imaging device or narrowing the period of the gratings. A radiation source generates radiation on a radiation path toward the grating section. The grating section comprises a G1 grating and a refraction-enhancing grating. The G1 grating has a G1 periodic structure that forms radiation converging points where an intensity of the radiation is increased between the G1 grating and a detector. The refraction-enhancing grating is located at the position of the radiation converging points and has enhancement planes and that increase the refraction angle of the radiation. The detector detects the radiation that has passed through the grating section.

Radiographic imaging device
11644430 · 2023-05-09 · ·

A high-sensitive phase imaging is achieved using a grating section without upsizing the imaging device or narrowing the period of the gratings. A radiation source generates radiation on a radiation path toward the grating section. The grating section comprises a G1 grating and a refraction-enhancing grating. The G1 grating has a G1 periodic structure that forms radiation converging points where an intensity of the radiation is increased between the G1 grating and a detector. The refraction-enhancing grating is located at the position of the radiation converging points and has enhancement planes and that increase the refraction angle of the radiation. The detector detects the radiation that has passed through the grating section.

Pixel summing scheme and methods for material decomposition calibration in a full size photon counting computed tomography system

A method and a system for a two-step calibration method for the polychromatic semiconductor-based PCD forward counting model, to account for various pixel summing readout modes for imaging at different resolutions. 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. To correct the variation of the detector response due to different PCD sub-pixel summing schemes, the embodiments calibrate forward model parameters based on the various pixel readout modes.

SEMICONDUCTOR DEVICE AND MANUFACTURING METHOD THEREOF
20170373042 · 2017-12-28 ·

A semiconductor device includes n semiconductor chips stacked via electrical contacting means in the silicon substrate thickness direction, n being an integer larger than 2, a side face of the stacked semiconductor device in the substrate thickness direction being covered by a non-conductive layer. The shape of the side face with respect to a plan view of the stacked semiconductor device may be one of curved, convex, concave or circular.

SENSITIVITY CORRECTION COEFFICIENT CALCULATING SYSTEM AND X-RAY ANALYZER
20170371047 · 2017-12-28 · ·

The invention provides a sensitivity correction coefficient calculating system for an X-ray detector with which the sensitivity correction coefficient can be calculated using a multipurpose X-ray source instead of a specific X-ray source. In the sensitivity correction coefficient calculating system for an X-ray detector having a detection surface where detection elements for detection the X-ray intensity are aligned one-dimensionally or two-dimensionally, fitting is carried out on the measured X-ray intensity detected by a detection element using an approximation function so as to calculate the sensitivity correction coefficient using the calculated X-ray intensity calculated from the approximation function and the measured X-ray intensity.

Threshold voltage calibration and compensation circuit for a digital radiographic detector
09851459 · 2017-12-26 · ·

A two dimensional array of digital imaging pixels each include a photo-sensing element and a readout element. A test element within the two-dimensional array, a column of test elements peripheral to the array, or test monitoring circuits peripheral to the array are constructed using the same process as the readout elements. The test element within the array and the column of test elements are connected to a first and second external voltage sources. The test element within the two-dimensional array and the column of test elements may be connected to a test data line or to a data line used by the imaging pixels.

Apparatus and method for a high-flux photon-counting spectral application-specific integrated circuit (ASIC) having a charge summing mode

A method and apparatus is provided to detect and correct for distributed X-ray detection events in which the electrical signal arising from the detection of an X-ray is distributed across more than one element of an X-ray detection array. Examples of distributed-detection events include charge sharing across adjacent boundaries between detector elements and X-ray fluorescence between detector elements. Distributed-detection events can be determined by their corresponding to a partial-detection energy that is in a range of energies great than an upper energy for noise and cross-talk and less than a lower energy for an X-ray spectrum from an X-ray source. For a distributed-detection event, the energy of the event is recorded using a sum of electrical signals from the detector elements of the event.