| 摘要 |
FIELD: medical equipment.SUBSTANCE: group of inventions refers to medical equipment, namely to computed tomography. Imaging system comprises source, which rotates around area of examination and emits radiation, which crosses examination area, radiation-sensitive detector array, evaluation device, which determines whether noise level in projection is reduced on basis of number of detected photons for projection, and device reducing noise level in projection data based on number of detected photons for projection, at that at least one projection includes number of detected photons, which corresponds to predetermined threshold value of number of photons and noise level which does not reduced, and at least one projection includes a number of detected photons, which does not correspond to predetermined threshold value of number of photons and noise level in which is decreased. Method of reducing noise level in projection consists in obtaining of these projection data generated by image forming system, determination of estimated number of detected photons for two-dimensional projection of projection data and generating signal, which is its indicator and reduction of noise level in projection on basis of said signal.EFFECT: using inventions enables reducing noise level on basis of image.13 cl, 3 dwg |
