1526 results about "Radiation imaging" patented technology

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.

A radiation imaging apparatus comprises a read unit reading the electric signal in the radiation detecting elements in a radiation detecting unit comprises the radiation detecting elements converting incident radiation into electric signals arranged two-dimensionally, a control unit controlling the radiation detecting unit with such that a first radiation detecting element group is made senseless state and a second radiation detecting element group is made sensible state, and a signal processing unit performing a subtraction processing such that the electric signal in the radiation detecting elements made senseless state read by the read unit is subtracted from the electric signal in the radiation detecting elements made sensible state read by the read unit according to the state control by the control unit, to reduce conspicuous line noise in an image by a relatively simple configuration.

A radiation imaging apparatus in which early recognition of breast cancer can be made possible by acquiring both a radiation tomographic image that accurately displays a tumor mass and a radiation planar image that accurately displays calcification. The apparatus includes an image processing unit for generating a tomographic image signal in a first imaging mode and generating a planar image signal in a second imaging mode, a computing unit for computing an imaging direction for obtaining a radiation planar image based on a location designated in a radiation tomographic image, and a control unit for controlling a rotational driving device and a radiation generating unit to obtain the radiation tomographic image in the first imaging mode, and controlling the rotational driving device according to the computed imaging direction and controlling the radiation generating unit to obtain the radiation planar image in the second imaging mode.

The invention provides novel Compton camera detector designs and systems for enhanced radiographic imaging with integrated detector systems which incorporate Compton and nuclear medicine imaging, PET imaging and x-ray CT imaging capabilities. Compton camera detector designs employ one or more layers of detector modules comprised of edge-on or face-on detectors or a combination of edge-on and face-on detectors which may employ gas, scintillator, semiconductor, low temperature (such as Ge and superconductor) and structured detectors. Detectors may implement tracking capabilities and may operate in a non-coincidence or coincidence detection mode.

Radioimaging methods, devices and radiopharmaceuticals therefor.

An imaging apparatus capable of reducing a line noise artifact in a simple configuration without complicated operations includes: a plurality of pixels arranged in row and column directions and having a photoelectric conversion element and a switch element; a plurality of signal wirings connected to the plurality of switch elements in the column direction; a read out circuit connected to the plurality of signal wirings; and a power source for supplying a voltage to the photoelectric conversion element. With the configuration, the plurality of pixels are classified into a plurality of groups, and the power sources are independently provided for each of the plurality of groups.

A radiation imaging system includes an X-ray source, first and second absorption gratins disposed in a path of X-rays emitted from the X-ray source, and an FPD. The second absorption grating is stepwise slid in an X direction relatively against the first absorption grating. Whenever the second absorption grating is slid, the FPD captures a fringe image and produces image data. A correction section corrects the image data for spatial variation of X-ray transmittance of the first and second absorption gratings. A phase contrast image generator produces a phase contrast image from the corrected image data. An X-ray absorption contrast image generator calculates a value related to an average of the corrected image data on a pixel-by-pixel basis, and produces an X-ray absorption contrast image from the value.

To provide a radiation imaging apparatus which is capable of both connecting state radiographing for radiographing with a C arm connected and non-connecting state radiographing for radiographing with the C arm disconnected, and is convenient and obtains high quality images, the apparatus includes: a flat panel detector; a holding unit for holding at least the flat panel detector;and a control unit for controlling the flat panel detector. With the configuration, the flat panel detector can be connected to and disconnected from the holding unit; connecting state radiographing can be performed with the flat panel detector connected to the holding unit, and non-connecting state radiographing can be performed with the flat panel detector disconnected from the holding unit; the control unit controls the flat panel detector such that a heat generation quantity of the flat panel detector during the non-connecting state radiographing can be lower than a heat generation quantity of the flat panel detector during the connecting state radiographing.

In a radiation imaging apparatus having a radiation generator, an imaging unit including a detecting unit for detecting radiation to generate a radiation image data, a carriage for carrying the radiation generator, and an operating unit for providing an interface to a user, it is decided whether the radiation imaging apparatus is in a moving state or not. When it is decided that the radiation imaging apparatus is in a moving state, the operation function of the operating unit for the radiation detector and the imaging unit is limited.

An X-ray imaging system includes first to third absorption gratings. Initially, the third absorption grating is disposed in a Z axis orthogonal to a detection surface of a FPD, and the position of the third absorption grating is adjusted in θx and θy directions based on a dose of X-rays having passed through the third absorption grating. Then, the first absorption grating is disposed in the Z axis so as to produce a moiré pattern. The position of the first absorption grating is adjusted in the θx and θy directions so that a frequency of the moiré pattern detected by the FPD becomes uniform. Then, the position of the first absorption grating is adjusted in a Z or θz direction so that the FPD loses the detection of the moiré pattern. After that, the second absorption grating is aligned in a like manner as the first absorption grating.

A lamp emits pulse-shaped visible light when a wait period begins. If a radiation emission switch is not pressed in the wait period, X-ray radiation is not emitted from an X-ray source, and no charges are accumulated in photoelectric conversion elements of an X-ray imaging apparatus. In a non-read period, although signals are sequentially read from the photoelectric conversion elements, an output signal does not change. When the radiation emission switch is pressed in synchronization with a radiation-induced signal in a certain wait period, the X-ray source emits X-rays. After irradiation of X-rays, a photoelectric conversion period transitions to an actual read period. In the photoelectric conversion period, X-rays are emitted and transmitted X-ray information of a patient are accumulated in the photoelectric conversion elements of the X-ray imaging apparatus. In the actual read period, the accumulated information is read.

A radiation imaging device (10). The radiation image device (10) comprises a subject radiation station (12) producing photon emissions (14), and at least one semiconductor crystal detector (16) arranged in an edge-on orientation with respect to the emitted photons (14) to directly receive the emitted photons (14) and produce a signal. The semiconductor crystal detector (16) comprises at least one anode and at least one cathode that produces the signal in response to the emitted photons (14).

A method of imaging, comprising:(a) providing an isotope at a low dosage in a body of a patient;(b) receiving radiation generated by said isotope from said body using a radiation camera; and(c) reconstructing a 3D distribution of said isotope from said received radiation,wherein the dosage is less than ⅓ of a standard dose set forth in Table 5.

An X-ray imaging system includes an X-ray source, first and second absorption gratings, and an FPD. The first absorption grating passes X-ray emitted from the X-ray source to form a G1 image. The second absorption grating modulates intensity of the G1 image at each of relative positions to form two or more fringe images. The relative positions differ in phase with respect to a period pattern of the G1 image. The FPD detects two or more frames of image data of the fringe images. A defective pixel detector reads two or more frames of image data stored in a memory and obtains a characteristic value of an intensity modulated signal on a pixel-by-pixel basis based on the read image data. The defective pixel detector detects a defective pixel based on the characteristic value obtained.

When a gain correction is performed for the radiographed object image, the acquisition of the object image having a high grade quality and no artifact is realized. For that purpose, an image storing unit is provided for storing an image for correction radiographed based on conditions set with the table in a state in which no object exists to each operation modes of the plurality of operation modes; and an image processing unit is provided for performing a gain correction processing of the radiographed object image and performs the gain correction processing of the radiographed object image obtained based on the conditions set in the table of the operation mode selected by the selecting unit in a state in which the object exists using a corresponding image for correction extracted from the image storage unit based on the operation mode selected by the selecting unit.

A radiation imaging system includes an X-ray source, first and second absorption gratings disposed in a path of X-rays emitted from the X-ray source, and an FPD. The second absorption grating is slid stepwise in an X direction relative to the first absorption grating. Whenever the second absorption grating is slid, the FPD captures a fringe image. From the captured plural fringe images, an intensity modulation signal of each pixel is obtained. A positional deviation detector calculates an amplitude value of the intensity modulation signal. The positional deviation detector compares a measurement of the amplitude value with predetermined first and second threshold values. If the measurement is less than the first threshold value, a warning signal is outputted. If the measurement is less than the second threshold value, an error signal is outputted.