摘要:
The invention relates to an X-ray detector (30) that comprises an array of sensitive elements (Pi−1,b, Pia, Pib, Pi+1,a, Pi+1,b) and at least two analyzer gratings (G2a, G2b) disposed with different phase and/or periodicity in front of two different sensitive elements. Preferably, the sensitive elements are organized in macro-pixels (IIi) of e.g. four adjacent sensitive elements, where analyzer gratings with mutually different phases are disposed in front said sensitive elements. The detector (30) can particularly be applied in an X-ray device (100) for generating phase contrast images because it allows to sample an intensity pattern (I) generated by such a device simultaneously at different positions.
摘要:
Scattered radiation has non-intuitive properties. A signalling system (28) is presented which provides a perceptible signal (34) being indicative of a predicted or measured spatial distribution of scattered radiation. An embodiment provides for easy assessment of the individual risk of scattered radiation exposure for personnel working in an environment exposed to scattered radiation. A method for predicting a distribution of scattered radiation takes into account at least one object related parameter (18) and at least one radiation related parameter (22) and, in response hereto, predicts a distribution of scattered radiation.
摘要:
The invention relates to an X-ray detector (30) that comprises an array of sensitive elements (Pi−1,b, Pia, Pib, Pi+1,a, Pi+1,b) and at least two analyzer gratings (G2a, G2b) disposed with different phase and/or periodicity in front of two different sensitive elements. Preferably, the sensitive elements are organized in macro-pixels (IIi) of e.g. four adjacent sensitive elements, where analyzer gratings with mutually different phases are disposed in front said sensitive elements. The detector (30) can particularly be applied in an X-ray device (100) for generating phase contrast images because it allows to sample an intensity pattern (I) generated by such a device simultaneously at different positions.
摘要:
An apparatus includes an integrator (120) that produces a pulse having a peak amplitude indicative of the energy of a detected photon. First discharging circuitry (136) discharges the integrator (120) at a first discharging speed, and second discharging circuitry (124) discharges the integrator (120) at a second discharging speed. The first discharging speed is less than the second discharging speed.
摘要:
The invention is directed at an apparatus (10), an imaging device and a method for detecting X-ray photons, in particular photons (32,34) in a computer tomograph. Photons (32,34) are converted into an electrical pulse and compared against a threshold using a discriminator (20). The electrical network (12) performing these functions comprises a switching element (28), that can modify the electrical path (22) along which the process signals travel. The trigger signal (VT) for actuating the switching element (28) is derived from an electrical state of the electrical path (22). If a pulse associated to a photon (32,34) is detected, the switching element (28) is actuated in order to avoid that the processing of the charge pulse stemming from a first photon (32) is affected by a subsequent second photon (34).
摘要:
Computed tomography (CT) systems are provided that utilize x-ray tube spectra in connection with the generation and/or interpretation of CT data. The disclosed systems and methods use x-ray tube spectra associated with CT systems to enhance contrast and/or image quality, e.g., by making use of energy selective detection techniques. The x-ray spectra may be determined in a variety of ways, e.g., incorporation of a spectral x-ray tube model into the CT system, using the output of Monte-Carlo simulations, and/or processing measured experimental spectral tube data for the CT system. The x-ray tube spectra is generally generated by and/or stored in a computer system associated with the CT system and may be used in support of an energy selective detective method and/or generation of spectral CT images.
摘要:
An imaging system includes a scintillator array (202) and a digital photomultiplier array (204). A photon counting channel (212), an integrating channel (210), and a moment generating channel (214) process the output signal of the digital photomultiplier array (204). A reconstructor (122) spectrally resolves the first, the second and the third output signals. In one embodiment, a controller (232) activates the photon counting channel (212) to process the digital signal only if a radiation flux is below a predetermined threshold. An imaging system includes at least one direct conversion layer (302) and at least two scintillator layers (304) and corresponding photosensors (306). A photon counting channel (212) processes an output of the at least one direct conversion layer (302), and an integrating channel (210) and a moment generating channel (214) process respective outputs of the photosensors (306). A reconstructor (122) spectrally resolves the first, the second and the third output signals.
摘要:
An apparatus includes an integrator (120) that produces a pulse having a peak amplitude indicative of the energy of a detected photon. First discharging circuitry (136) discharges the integrator (120) at a first discharging speed, and second discharging circuitry (124) discharges the integrator (120) at a second discharging speed. The first discharging speed is less than the second discharging speed.
摘要:
The invention is directed at an apparatus (10), an imaging device and a method for detecting X-ray photons, in particular photons (32, 34) in a computer tomograph. Photons (32, 34) are converted into an electrical pulse and compared against a threshold using a discriminator (20). The electrical network (12) performing these functions comprises a switching element (28), that can modify the electrical path (22) along which the process signals travel. The trigger signal (VT) for actuating the switching element (28) is derived from an electrical state of the electrical path (22). If a pulse associated to a photon (32, 34) is detected, the switching element (28) is actuated in order to avoid that the processing of the charge pulse stemming from a first photon (32) is affected by a subsequent second photon (34).
摘要:
Device and method for synchronously switching activating a first and second charge accumulation section (31, 32) for a duration of a first and second predetermined sub-frame and a first and second X-ray source until lapse of a predetermined time frame for each of the first and second charge accumulation section (31, 32) for the accumulation of a plurality of temporally distributed partial charges according to an origin of a respective one of the plurality of spatially distributed X-ray sources so as to establish a specific relation between the focal spot position and a rule for accumulating the respective partial measurements, e.g. temporally distributed partial charges, belonging to the same focal spot positions, and to keep the focal spot temperature low by only activating the focal spot for a limited time according to a sub-frame.