Abstract: A CT image reconstruction method includes substituting other projection data, which has a predetermined positional relationship to projection data that is found defective during scanning, for the defective data, and interpolating back projection data using a value and information on a scanned position that are contained in the substitute data.

Abstract: The present invention provides a detector which suppress the crosstalk between detector cells while improving the acquisition efficiency of X-ray radiation. The detector includes a plurality of detector cells, arranged along a detection plane of X-ray, in which each detector cell has a scintillator unit made of a scintillator, and a photodiode for transduce the light incoming from the scintillator unit into electric signals. The scintillator units are partitioned each from another by the border, which has a groove extending in the channel and row directions. A scintillator is provided in some part of the border in the incident X-ray direction.

Abstract: The present invention provides a detector which suppress the crosstalk between detector cells while improving the acquisition efficiency of X-ray radiation. The detector includes a plurality of detector cells, arranged along a detection plane of X-ray, in which each detector cell has a scintillator unit made of a scintillator, and a photodiode for transduce the light incoming from the scintillator unit into electric signals. The scintillator units are partitioned each from another by the border, which has a groove extending in the channel and row directions. A scintillator is provided in some part of the border in the incident X-ray direction.

Abstract: With the object of realizing an X-ray CT apparatus which performs a plurality of pieces of imaging small in resolution degradation too simultaneously while suppressing an expansion of a data acquisition section that receives an electric signal of an X-ray detector, such an array that X-ray detectors in a channel direction are operated with the two as one pair is made by first detector switching means of a switching unit. This array moved by one X-ray detector in the channel direction is alternately repeated in the row or channel direction. Therefore, even when the number of receivers is small, data extending over a wide imaging range can simultaneously be collected while the degradation of resolution is being suppressed to a minor degree. By extension, imaging more coincident with an operator-aimed image can be done by making the switching use of imaging in high resolution.

Abstract: To reduce a collimator thickness, plural collimators are not erected each independently on a scintillator array but are integrated into a collimator unit by molding with use of a plastic resin and the collimator unit is installed on the scintillator array. Even if the collimator thickness is made small, resulting in deterioration of the rigidity strength, there occurs no problem and thus the collimator thickness can be made as small as 200 ?m or less.

Abstract: An X-ray CT system comprises: an X-ray generator that generates two cone beam X-radiations which pass through two successive slabs; an X-ray detector that detects a two-dimensional distribution of intensities exhibited by the two cone beam X-radiations having passed through the two slabs; an acquisition unit that acquires a plurality of view of projection data representing the two slabs on the basis of detection signals sent from the X-ray detector; and a reconstruction unit that reconstructs an image according to the projection data.

Abstract: With the object of realizing an X-ray CT apparatus which performs a plurality of pieces of imaging small in resolution degradation too simultaneously while suppressing an expansion of a data acquisition section that receives an electric signal of an X-ray detector, such an array that X-ray detectors in a channel direction are operated with the two as one pair is made by first detector switching means of a switching unit. This array moved by one X-ray detector in the channel direction is alternately repeated in the row or channel direction. Therefore, even when the number of receivers is small, data extending over a wide imaging range can simultaneously be collected while the degradation of resolution is being suppressed to a minor degree. By extension, imaging more coincident with an operator-aimed image can be done by making the switching use of imaging in high resolution.

Abstract: An X-ray distribution adjusting filter apparatus for supplying a desired X-ray intensity distribution or adjusting the X-ray distribution to a desired profile, the bowtie filter as the X-ray distribution adjusting filter apparatus has a fixed section having a base portion and inclined portions, first and second movable sections configured to be tiltable pivoting on a center point, and first and second deformable sections whose cavities defined by the fixed section, the movable sections and an expansible bellows is to be filled with fluid, wherein the inclined faces of the fixed section and the flat faces of the movable sections are caused to approach or move away from each other by the tilting of the movable sections pivoting on the center point to vary the quantity of the fluid in the cavities of the movable sections, and to vary the sectional shape of the X-ray absorbing portion of the bowtie filter.

Abstract: A CT image reconstruction method includes substituting other projection data, which has a predetermined positional relationship to projection data that is found defective during scanning, for the defective data, and interpolating back projection data using a value and information on a scanned position that are contained in the substitute data.

Abstract: An X-ray CT apparatus that includes a multidetector wherein a scintillator unfractionated by reflectors or slits or the like is laminated on an upper surface of a photodiode array comprising photodiodes two-dimensionally arranged in channel and slice directions, a DAS which acquires signals delivered from the photodiodes, and a signal transfer section which switches whether to transfer the signals sent from the respective ones of the photodiodes to the DAS or to add the signals sent from the 2×2 photodiodes of the photodiodes and transfer the result of addition to the DAS.

Abstract: The present invention comprises: an X-ray generator that generates two cone beam X-radiations which pass through two successive slabs; an X-ray detector that detects a two-dimensional distribution of intensities exhibited by the two cone beam X-radiations having passed through the two slabs; an acquisition unit that acquires a plurality of view of projection data representing the two slabs on the basis of detection signals sent from the X-ray detector; and a reconstruction unit that reconstructs an image according to the projection data.

Abstract: An X-ray distribution adjusting filter apparatus for supplying a desired X-ray intensity distribution or adjusting the X-ray distribution to a desired profile, the bowtie filter as the X-ray distribution adjusting filter apparatus has a fixed section having a base portion and inclined portions, first and second movable sections configured to be tiltable pivoting on a center point, and first and second deformable sections whose cavities defined by the fixed section, the movable sections and an expansible bellows is to be filled with fluid, wherein the inclined faces of the fixed section and the flat faces of the movable sections are caused to approach or move away from each other by the tilting of the movable sections pivoting on the center point to vary the quantity of the fluid in the cavities of the movable sections, and to vary the sectional shape of the X-ray absorbing portion of the bowtie filter.

Abstract: In an X-ray computerized tomography apparatus, a water phantom is interposed between an X-ray tube unit and an X-ray detector in place of a subject under examination and a plurality of pieces of data detected by a plurality of X-ray detector elements are previously measured as a pieces of compensation data while shifting the X-focal point to different positions. Compensation data corresponding to the actual position of the X-ray focal point, which shifts according to the thermal state of the X-ray tube unit, is selected to correct detect data obtained for a subject under examination, permitting optimum compensation of variations in sensitivity among the X-ray detector elements for any position of the X-ray focal point, thereby preventing a ring-like artifact from being produced on a tomography image.

Abstract: An X-ray computerized tomographic (CT) apparatus capable of facilitating alignment of focal spot position at the time of replacing an X-ray tube anew and capable of easily correcting the focal spot position even when the focal spot position of the X-ray tube is deviated. Thereby, the focal spot position of the X-ray tube remains fixed in a predetermined position. The X-ray computerized tomographic (CT) apparatus includes an X-ray tube which is freely movable in at least one of a horizontal direction and a vertical direction; a detection unit for detecting a dislocated degree of the focal spot position of the X-ray tube; and a controlling unit for automatically controlling the focal spot position of the X-ray tube based on data obtained from the detection unit so that the focal spot position of the X-ray tube remains fixed in a predetermined position.

Abstract: In a CT (computerized tomographic) scanning apparatus, a biological body under medical examination is scanned to acquire image data on the scanned body, whereby a computerized tomographic image of the scanned body is reconstructed by processing the acquired image data. The CT scanning apparatus comprises: an AC/DC converting unit for converting AC (alternating current) power supplied from a commercial power source into first DC (direct current) power; a peak power consumption unit for consuming peak power during a scanning operation; and a secondary battery unit rechargeable by the first DC power supplied from the AC/DC converting unit and capable of supplying second DC power to the peak power consumption unit during at least the scanning operation.

Abstract: In a power source device for X-ray system, circuit units are mounted on chassises, respectively and chassises are fixed in a casing and are electrically insulated from the casing by insulative members. The circuit units are electrically connected through a cable to a ground terminal of the casing which is connected to the ground. The chassises are also connected through a cable to a ground terminal of a panel board which is connected to the ground.

Abstract: A frame structure for a CT scanner, in which a dome for containing a scanner for an object or subject to be examined has an imaging space in its central portion, and a bed plate support mechanism carries the subject, and in which a bed plate slidably drive mechanism moves the bed plate into or out of the imaging space of the dome, and the bed plate support mechanism and the bed plate slidably drive mechanism are integrally provided to the dome.

Abstract: A fourth-generation X-ray CT scanner device comprises an X-ray tube for irradiating X-rays in a sector form to an object while moving on a circular orbit around the object, an annular X-ray detector array disposed coaxially with and inside the circular orbit of the X-ray tube and arranged to surround the object, for detecting the X-rays which have been irradiated from the X-ray tube and passed through the object for each channel, and a reconstruction unit for acquiring an output of the detector array to effect the reconstruction process and create a tomographic image. The X-ray array is formed of a large number of solid-state X-ray detectors and a plurality of the detectors constitute a detector module, and the array includes a large number of modules.

Abstract: An X-ray generator system has first and second switching devices such as transistors which are complementarily turned on and off to intermittently apply a DC voltage to the primary winding of a transformer for thereby inducing a high voltage across secondary windings of the transformer for enabling an X-ray tube to emit X-rays. The X-ray generator has a control mode in which the first and second switching devices are simultaneously turned on immediately before they start being complementarily turned on and off, for allowing the high voltage to have a sharply rising positive-going edge.

Abstract: A high DC voltage generator for an X-ray tube includes a low voltage rectifier for rectifying a low AC input voltage to produce a low DC voltage, a DC-to-DC converter for converting the low DC voltage into a high DC voltage for the X-ray tube, and a controller for controlling transition characteristics of turning-on and off the X-ray tube. The controller shortens a rising time period of the high DC voltage until a rating anode voltage is applied to the X-ray tube after turn-on operation.