摘要:
Even when areas delimited by delimiting points are not appropriate and area division has failed, success or failure of area division in such areas can easily be determined by applying a map determination condition in the map determining step (step S50). And since the areas delimited by the delimiting points are changed and the map determining step (step S50), including also steps S22 and S23 and steps S30 and S40, is repeated until the map determination condition is satisfied, the areas satisfying the map determination condition are determined appropriate and the area division in such areas can be carried out accurately. Even when there is distortion, a two-dimensional position map can be corrected accurately.
摘要:
Even when areas delimited by delimiting points are not appropriate and area division has failed, success or failure of area division in such areas can easily be determined by applying a map determination condition in the map determining step (step S50). And since the areas delimited by the delimiting points are changed and the map determining step (step S50), including also steps S22 and S23 and steps S30 and S40, is repeated until the map determination condition is satisfied, the areas satisfying the map determination condition are determined appropriate and the area division in such areas can be carried out accurately. Even when there is distortion, a two-dimensional position map can be corrected accurately.
摘要:
A PET apparatus and a timing correction method of this invention select two target gamma-ray detectors which count coincidences, select a reference detector which is one detector out of the two selected gamma-ray detectors, select a gamma-ray detector different from the other, opposite detector, and when repeating the selection, make a time lag histogram concerning two gamma-ray detectors selected in the past a reference, and correct a time lag histogram concerning gamma-ray detectors selected this time based on the reference. By repeating an operation to make the corrected time lag histogram concerning the two gamma-ray detectors a new reference, an optimal time lag histogram can be obtained without repeating many measurements and computations.
摘要:
Disclosed is a radiation detector signal processor that allows accurate identification of a variation in fluorescence detection intensity. With a construction of the disclosure, the variation is obtainable in accordance with detection data (a peak value) of fluorescence and a specified number of light spread indicating how the fluorescence generated in a scintillator spreads spatially until reaching each of detecting elements. Such a construction allows accurate obtainment of the variation in the radiation detector in which the fluorescence is detected with a plurality of light detecting elements while spreading. A radiation detector is adjusted in accordance with the variation, achieving more accurate positional identification by the radiation detector.
摘要:
A PET apparatus and a timing correction method of this invention select two target gamma-ray detectors which count coincidences, select a reference detector which is one detector out of the two selected gamma-ray detectors, select a gamma-ray detector different from the other, opposite detector, and when repeating the selection, make a time lag histogram concerning two gamma-ray detectors selected in the past a reference, and correct a time lag histogram concerning gamma-ray detectors selected this time based on the reference. By repeating an operation to make the corrected time lag histogram concerning the two gamma-ray detectors a new reference, an optimal time lag histogram can be obtained without repeating many measurements and computations.
摘要:
Disclosed is a radiation detector signal processor that allows accurate identification of a variation in fluorescence detection intensity. With a construction of the disclosure, the variation is obtainable in accordance with detection data (a peak value) of fluorescence and a specified number of light spread indicating how the fluorescence generated in a scintillator spreads spatially until reaching each of detecting elements. Such a construction allows accurate obtainment of the variation in the radiation detector in which the fluorescence is detected with a plurality of light detecting elements while spreading. A radiation detector is adjusted in accordance with the variation, achieving more accurate positional identification by the radiation detector.
摘要:
The display apparatus of this invention, even when edges of an IP image with measurement information on β+ rays are indistinct and an area to be measured is unclear, includes a main screen for displaying in superimposition the IP image and a scanner image with morphological information on blood, whereby an area measured of the scanner image can be grasped visually from the IP image. Even if traces of movement of the blood appear on the IP image, the position of an object to be measured can be determined by displaying the IP image and the scanner image in superimposition.
摘要:
In a DOI radiation detector, scintillation crystals are arranged in three dimensions on a light receiving surface of a light receiving element, and a response of a crystal having detected a radiation ray can be identified on the light receiving surface. Thereby, a position at which the radiation ray is detected is determined in three dimensions. In this DOI radiation detector, regular triangular prism scintillation crystals are used, and response positions of the respective crystals are shifted for each set. This allows crystal identification without loss even with a structure such as a three-layer or six-layer structure hard to achieve by a quadrangular prism scintillation crystal.
摘要:
In a scintillator of a radiation detector according to this invention, first reflectors provided in first scintillation counter crystal layer adjacent to one another have gaps wider than first reflectors provided in second scintillation counter crystal layer such that an overall width of the first reflectors in the first scintillation counter crystal layer in an arranging direction is identical to an overall width of the first reflectors in the second scintillation counter crystal layer in an arranging direction. Such construction improves spatial resolution at a side end of the scintillator.
摘要:
An emitted light in a scintillator element is sufficiently diffused in the scintillator array to be inputted into a photo multiplier tube (PMT) using a side face light guide that is optically coupled with respect to a side face of a scintillator array, except for in an end area. In the end area, the emitted light in the scintillator element is sufficiently diffused also in the side face light guide to be inputted into the PMT. In this way, also in the scintillator element in the end area, the emitted light is sufficiently diffused in the side face light guide, and thereby the precision of separation of a position calculation map in the end area may be improved, resulting in improved discriminating ability of a position in the end area.