Hitachi Medical Corporation

Rika Baba

Ken Ueda

Hironori Ueki

Keiji Umetani

Hisatake Yokouchi

Yoichi Onodera

Ken Ishikawa

Akira Kuba

Hiroyuki Kawai

Takashi Ishiguro

Kensuke Sekihara

Fumitaka Takahashi

Koichi Koike

Masayuki Tsuneoka

Masakazu Okabe

Tomoharu Kajiyama

Shigekazu Hara

Keiji Umetake

Nobuhisa Kasagima

Disclosed is an X-ray imaging apparatus in which a correction function used to correct scattered X-rays and a correction function used to correct beam hardening can be simply and precisely determined so that the correcting operations are performed in an appropriate sequence using the correction functions thus determined to enhance the precision in the correction and improve the image quality. The scattered X-rays and the beam hardening are corrected sequentially in this order, using the scattered X-ray correction function and the beam hardening correction function, both calculated using measured data for calculating the correction functions. The scattered X-ray correction function approximates as to each transmission distance, the data measured with changes in the transmission distance and with changes in the scattered X-ray amount, and associates the correction value thus obtained with transmittance data. Upon calculation of the beam hardening correction function, data measured with changes in the transmission distance is converted into projection data and is linearly approximated to obtain an ideal amount of beam hardening.

Radiation imaging device

An X-ray measuring instrument in which an object under examination is irradiated with X-rays, measurement data on the object is detected, a filter for adjusting the amount of transmitted X-rays is disposed between an X-ray source and the object, the relative position of the X-ray source to the object is varied, and the acquired measurement data is computed. The measurement data is subjected to logarithm transform to acquire projection data, and the amount of absorbed X-rays of the filter corresponding to the acquired projection data is determined. The thickness of the filter is computed by using a predetermined transform formula for the acquired amount of absorbed X-rays. A correction coefficient corresponding to the projection data acquired from the computed thickness of the filter is determined, and the projection data is multiplied by the determined correction coefficient. The projection data multiplied by the correction coefficient is restructure-computed to obtain a three-dimensional image.

X-ray measuring instrument

An x-ray measuring apparatus comprises an x-ray source, an x-ray detector, a rotating device, and a processor. The x-ray source generates x-rays to be emitted to a subject. The x-ray detector detects measurement data regarding the subject. The rotating device changes a relative position of the x-ray source and the x-ray detector with respect to the subject. The x-ray detector is shifted by a distance shorter than half the length of the x-ray detector along a line parallel to the plane of rotation, in a tangential direction of the plane of rotation generated by the x-ray source. The processor obtains projection data by executing a logarithmic converting process for the measurement data, multiplies a value of the projection data by a weight, and obtains reconstructed data therefrom.

X-ray measuring apparatus

The present invention provides an x-ray measuring apparatus for diagnosis having high spatial resolution and high sensitivity, which includes: an x-ray source for emitting x-rays from an x-ray focal spot; an x-ray detector in which a plurality of sensing elements each having a sensitive part and a blind part surrounding the sensitive part are arranged two-dimensionally; data processing means for collecting output signals of the sensing elements and performing data processing; and an anti-scatter grid disposed between the x-ray focal spot and the x-ray detector with predetermined distance from the position of the x-ray focal spot and in which an x-ray transmitting member and an x-ray shielding member are alternately arranged in a first direction. A pitch in the first direction of linear images projected on a sensing surface of the x-ray detector of the x-ray shielding member by the x-ray is set to be substantially an integral multiple of two or larger of the pitch of arrangement of the sensing elements in the first direction. In such a manner, a moir&#xe9;-free image of a wide field of view is obtained.

An X-ray based measuring device of the invention includes: X-ray imaging means ( ) which have their detection areas divided into a plurality of detector units ( to &prime;), detect X-rays transmitted through an inspection object ( ), and pick up X-ray images in interested areas ( &prime;) of the inspection object; conversion means ( ) for converting analog image signals read from the detector units into digital image data under specified conversion conditions for each of the detector units; and re-conversion means ( ) for converting the digital image data obtained for each of the detector units under re-conversion conditions corresponding to the specified conversion conditions, wherein analog image signals are A/D converted into digital image data under optimum conversion conditions for each detector unit, and X-ray images in interested areas of the inspection object are sequentially picked up.

X-ray based measuring device

Between an X-ray generating system and an X-ray image detecting system arranged opposite to the X-ray generating system, an examination object supporting system is arranged and contains a straight movement table provided on a rotary table supported by a rotary table supporting member, and an examination object supporting member for supporting the examination object under either a standing position or a sitting position on the straight movement table. While the examination object is rotated by the rotary table, the examination object is continuously moved (reciprocating movement) by the straight movement table along a direction parallel to the rotation plane, and X-ray images of the examination object are acquired along a plurality of directions during both the rotating operation and the moving operation. As a result, both an X-ray tomographic image and a three-dimensional image (stereoscopic image) of a wider area than a viewing field of an X-ray I.I. can be acquired. Since the viewing fields of the X-ray tomographic image and of the 3-dimensional image can be employed, both diagnostic performance and also a diagnostic efficiency with respect to a large organ such as a lung can be improved.

X-ray examination apparatus and imaging method of X-ray image

The method for generating an X-ray image of the present invention by correcting a measured fluorographic image or radiographic image and removing the veiling glare component and scattered X-ray component has (1) a step of generating a veiling glare component image and a scattered X-ray component image corresponding to the fluorographic image or radiographic image from the measured fluorographic image or radiographic image independently and (2) a step of obtaining the difference between the measured fluorographic image or radiographic image and the veiling glare component image and scattered X-ray component image and executes a correction of removing the veiling glare component and scattered X-ray component from the measured fluorographic image or radiographic image.

Method for generating X-ray image and apparatus therefor

An X-ray apparatus acquires an X-ray image of an object by radiating X-rays to the object and includes an X-ray radiator for radiating X-rays to an object. An imager acquires an X-ray image of the object and radiation dose controller controls the radiation dose so as to acquire an X-ray image having a predetermined X-ray relative noise level on the basis of an image level of a predetermined area in the X-ray image.

X-ray apparatus

A radiographic apparatus which can improve at high speed the picture quality of an X-ray fluoroscopic image or an X-ray radiographic image is disclosed. In a radiographic apparatus acquiring an X-ray fluoroscopic image or an X-ray radiographic image and having a scattered X-ray corrector for eliminating a scattered X-ray component from the acquired X-ray fluoroscopic image or X-ray radiographic image, the scattered X-ray corrector comprises: scattered X-ray intensity distribution function generator for generating a scattered X-ray intensity distribution function on the basis of the acquired X-ray fluoroscopic image or X-ray radiographic image; a moving average calculator for executing moving average calculation a plurality of times in each of the vertical and lateral directions of the acquired X-ray fluoroscopic image or X-ray radiographic image; a window width calculator for calculating a window width of the moving average calculation on the basis of the scattered X-ray intensity distribution function; and a difference calculator means for calculating the difference between the acquired X-ray fluoroscopic image or X-ray radiographic image and an image to which the moving average calculation is performed.

In order to image an object larger than a field of view for observation, imaging is effected by dividing it into several times and pictures thus imaged are synthesized to constitute a whole image. In order to image several times, only a detecting unit is moved and an X-ray source is substantially fixed with respect to the object. Images thus obtained include a common part of the object and are joined so that the common part are overlapped on each other. In case where an image pick-up tube is included in the detecting unit, the image pick-up tube is made operable, after a period of time necessary for attenuation of microphonic noise has lapsed, measured from a point of time where the detecting unit has been stopped.

X-ray imaging system and method therefor

An X-ray apparatus for collecting X-ray transmission data of a subject from a plurality of directions to generate an X-ray transmission image or X-ray CT image of the subject, which includes an X-ray generator for generating an X-ray, an X-ray detector for detecting a transmission X-ray after the X-ray generated by the X-ray generator is transmitted through the subject, a rotation unit for rotating an imaging unit including the X-ray generator and the X-ray detector around the subject, a data collector for converting an output signal of the X-ray detector to a digital signal and collecting the digital signal, a signal processor for subjecting data collected by the data collector to a signal processing operation, a display for displaying thereon as an image the data collected by the data collector and the data subjected by the signal processor to the signal processing operation, and a position change unit for moving a relative position of a rotation center of the imaging unit and the subject in a direction parallel to a rotation plane of the rotation, and wherein the imaging unit is rotated by the rotator around the subject and at the same time the relative position is changed by the position change unit in a direction parallel to the rotation plane to perform X-ray fluoroscopic or radiographic operation or CT scan.

Method for X-ray fluoroscopy or radiography, and X-ray apparatus

An X-ray radiography method and apparatus in which a phantom such as a chart having elements arranged in predetermined positions is irradiated with X-rays and an X-rays detection unit detects signals thereof. An image of the chart is obtained and a center position of each of the elements in the image of the chart is obtained as well as for those elements which are not within the imaging field of view. Pixel positions for a distortion free image is obtained and a transform table is prepared making each of the pixel positions in the image of the chart correspond to each of the pixel positions in the distortion free image. A plurality of digital images of a subject to be examined are obtained and the digital images are corrected in accordance with the transform table. The corrected digital images are then joined together and a digital image is displayed, wherein common portions in the corrected images are in accordance with each other.

X-ray radiography method and system

A digital X-ray imaging system having an X-ray generator, an X-ray generator controller for controlling the X-ray generator, an X-ray detecting unit for detecting an X-ray transmitted through a subject, the X-ray detecting unit having an X-ray grid for shielding a scattered X-ray, a signal processor for acquiring a signal from the X-ray detecting unit and processing the signal to obtain a digital X-ray image of the subject, and a display device for displaying an image of the subject obtained by the signal processor. The system is provided with a position changing unit for changing a relative position between the X-ray detecting unit and the subject, a position change controller for controlling the position changing unit, and an imaging-sequence controller for controlling the position change controller and the X-ray generator controller. The imaging controller controls setting of each of a plurality of target imaging regions of the subject to generally a central area of an X-ray detecting plane of the X-ray detector, the X-ray detecting plane being an incident plane of the transmitted X-ray, and to set at least one imaging view field to contain an intermediate region between target imaging regions. The whole or part of a plurality of obtained digital X-ray images is used to join a single or a plurality of digital X-ray images for display.

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Kokubunji, Japan

Rika Baba