The invention relates to an image sensor comprising a photodetector array including neighboring photodetector elements, each photodetector element comprising:—a photodetector cell having a photodiode and a reset unit;—a cell control unit coupled with the photodetector cell and configured to reset the photodiode by means of the reset unit; wherein the cell control unit is configured to asynchronously effect resetting of the photodiode after a given dead time after detection of a photon.

Techniques are disclosed for systems and methods to provide a radiation detector module for a radiation detector. A radiation detector module includes a metallic and/or metalized enclosure, a radiation sensor disposed within the enclosure, readout electronics configured to provide radiation detection event signals corresponding to incident ionizing radiation in the radiation sensor, and a cap including an internal interface configured to couple to the readout electronics and an external interface configured to couple to a radiation detector, where the cap is configured to hermetically seal the radiation sensor within the enclosure. The cap may be implemented as an edge plated printed circuit board (PCB) including a slot configured to mate with a planar edge of an open surface of the enclosure, where the slot is soldered to the planar edge of the enclosure to hermetically seal the radiation sensor within the enclosure.

For dead time determination for a gamma camera or other detector, a long-lived point source of emissions is positioned so that the gamma camera detects the emissions from the source while also being used to detect emissions from the patient. The long-lived point source, in the scan time, acts as a fixed frequency source of emissions, allowing for dead time correction measurements that include the crystal detector effects.

A radiation imaging device capable of reducing the number of measurement times of calibration data used in pile up correction while maintaining the accuracy of the pile up correction. The radiation imaging device has a photon counting type detector to output an electric signal corresponding to energy of an incident radiation photon. The radiation imaging device includes: an extraction unit that extracts a component by the number of pile ups from a material spectrum, as a photon energy spectrum, obtained by detecting a radioactive ray transmitted through a calibration member, formed by combining plural basal substances having different radiation attenuation coefficients, with the photon counting type detector; and a synthesis unit that generates a calibrated equivalent spectrum, as a photon energy spectrum to be collated with an imaging spectrum obtained by imaging a subject by synthesizing the components by the number of pile ups based on the imaging spectrum.

A radiation sensor that may include a first transistor, a first isolated conductive structure that comprises a floating gate of the first transistor, a first group of radiation sensing diodes that are coupled to each other, wherein the first group is configured to convert sensed radiation that is sensed by the first group to a first output signal, and to change a state of the first isolated conductive structure using the first output signal, a second transistor, a second isolated conductive structure that comprises a floating gate of the second transistor, and a second group of radiation sensing diodes that are coupled to each other, wherein the second group is configured to convert sensed radiation that is sensed by the second group to a second output signal, and to change a state, under a control of the first transistor, of the second isolated conductive structure using the second output signal.

Methods, devices, systems, and apparatus for controlling pulse pileup are provided. In one aspect, a method of controlling pulse pileup includes: obtaining scan protocol parameters of a computed tomography (CT) device, the scan protocol parameters including an exposure voltage, an exposure duration for each revolution of a scanning of an object, and a number of views for each revolution, determining an angle of a radioactive source for an i-th view based on the number of views and an initial position of the radioactive source, obtaining an optimal exposure current for the i-th view under the exposure voltage by minimizing an output value of an objective function for the i-th view, and determining a current view based on the exposure duration for each revolution and a current exposure moment to perform the scanning on the object with the optimal exposure current for the current view.

A method and apparatus for resolving individual signals in detector output data are disclosed. One inventive aspect includes a processing circuit configured to receive detector output data wherein the detector output data may be stepped data or non-stepped data; transform the detector output data to produce stepped data wherein the detector output data is received as non-stepped data; detect at least one signal at least partially based on the stepped data; and estimate a parameter associated with the signal, wherein estimating the parameter may preferably comprise estimating a signal energy or signal time of arrival associated with the signal.

The invention provides a method of estimating an input count rate of a radiation pulse detector from a detector signal where some individual signal pulses making up the detector signal are closely spaced in time less than a minimum reliable detection gap (104,105; t.sub.c, t.sub.d). In one aspect, the individual signal pulses are detected using a detection algorithm and a plurality of interval start times (s.sub.k) are defined each interposed with at least one of the detected individual signal pulse arrival times (t.sub.k), each interval start time (s.sub.k) being later by at least the minimum reliable detection gap than a corresponding most recent detected individual signal pulse arrival time (t.sub.k−1). A corresponding plurality of individual signal pulse arrival intervals are calculated between each of the interval start times (s.sub.k) and a corresponding next detected individual signal pulse arrival time (t.sub.k).

The operation unit of radiation monitoring equipment reads in a real countable number (this time) and a cumulated countable number (previous time) in a every operational cycle, and judges whether the real countable number (this time) is within a permissible range, if the real countable number (this time) is judged to be within the permissible range, it is judged whether a number of times deviated from the permissible range is equal to zero or not, if the number of times deviated from the permissible range is judged to be equal to zero, a regular processing is performed, if the real countable number (this time) is judged to be out of a permissible range, 1 is added to the number of times deviated from the permissible range and further it is judged whether the added number of times deviated from the permissible range is equal to 1 or not.

A highly accurate pulse height spectrum is generated within a short amount of time, further cost of a radiation imaging apparatus being reduced by employing a detector that performs calibration using the pulse height spectrum. Provided is a pulse height spectrum acquisition device of a radiation detector including multiple counting units for counting a detected signal obtained by detecting incident X-rays, when a value of the detected signal is equal to or larger than a threshold, and for outputting a count value of each counting unit. This device is provided with a threshold setter configured to set to a first counting unit, a first threshold V1 as a threshold for a first measurement, along with setting to a second counting unit, a second threshold V2 larger than the first threshold V1, and to set to the first counting unit, a reconfigured threshold V1′ as the threshold for a second measurement, the reconfigured threshold V1′ being different from the first threshold V1, a measurement controller configured to perform multiple measurements, and a pulse height spectrum generator configured to generate a pulse height spectrum for the first threshold V1 of the first counting unit, on the basis of a difference in the count values from the first counting unit and the second counting unit, obtained by the multiple measurements performed by the measurement controller.