Hitachi, Ltd.

Hokkaido University

Fujifilm Healthcare Corporation

Takafumi Ishitsu

Kensuke Amemiya

Kazuma Yokoi

Katsutoshi Tsuchiya

Hiroshi Kitaguchi

Yuuichirou Ueno

Norihito Yanagita

Tomoyuki Seino

Yuichiro Ueno

Shinichi Kojima

Takashi Matsumoto

Keiji Kobashi

Tsuneaki Kawaguchi

Isao Takahashi

Naoyuki Yamada

Masafumi Onouchi

Yuichi Morimoto

Masatoshi Tanaka

Fumito Watanabe

Wataru Takeuchi

Atsuro Suzuki

Naoki Kubo

Nagara Tamaki

Shinya Kominami

Makoto Satou

Shinobu Irikura

Tatsuhiko Hayashi

There is provided a radiographic imaging apparatus capable of alignment of a detector with a collimator with a position of a radiation source fixed. The radiographic imaging apparatus includes the radiation source which irradiates a subject with radioactive rays, a plurality of detecting elements which detect photons in the radioactive rays, and a collimator which is disposed between the radiation source and the detecting elements and has a plurality of walls which form a plurality of passing holes that the radioactive rays pass. The detecting element and the collimator are aligned with each other in a direction which is orthogonal to a direction that the subject is irradiated with the radioactive rays such that a ratio or a difference between output signals from the detecting elements which are mutually adjacent with the wall being interposed falls within a predetermined range.

Radiographic imaging apparatus

There are provided a radiation detector module, a radiation detector, and a radiographic imaging apparatus which make it possible to increase the row number while suppressing a length in a body-axis direction. The radiation detector module includes a detector substrate on which a scintillator, a photodiode, and AD conversion chips are loaded, and a control substrate which supplies power to the detector substrate and controls the operation of an AD conversion unit (AFE) of each AD conversion chip of the detector substrate. The plurality of radiation detector modules configure a radiation detector which suppresses the length in the body-axis direction by connecting together the two substrates so as to form a two-stage structure by stacking connectors.

Radiation detector module, radiation detector, and radiographic imaging apparatus

The present invention provides a radiation imaging apparatus capable of maintaining the quality of an image obtained even when a dose incident on a radiation detector changes suddenly. The present invention is a radiation imaging apparatus including a radiation source, a radiation detector to detect radiation emitted from the radiation source, and a cooling unit to cool the radiation detector; and is characterized in that the radiation detector has a counting circuit to output a number of photons in radiation counted per unit time as a photon counting rate, and the cooling unit controls a coolability of the radiation detector in response to the photon counting rate.

Radiation imaging apparatus

To provide a radiation imaging system which is adapted to downsize a photon counting radiation detector including a semiconductor layer for detecting photons of radiation and a collimator for suppressing incidence of scattered rays, and which ensures high voltage resistance. The radiation imaging system includes: a radiation source; a radiation detector; and a support portion for supporting the radiation source and the radiation detector in opposed relation. The system has a structure wherein the radiation detector includes a plurality of detecting element modules arranged in an arcuate form. The detecting element module includes a base fixed to the support portion; a semiconductor layer; a high-voltage wire for supplying high voltage to the semiconductor layer; a collimator for suppressing scattered rays, and a supporting column disposed at place within a predetermined distance from the semiconductor layer.

Radiation imaging system

A radiation imaging apparatus provided with a detector capable of improving correction accuracy at a high counting rate. The present invention is provided with: grids that remove scattered beams that emanate from an object; and a plurality of detector sub-pixels arranged so as to divide the gap between the grids into three or more segments, wherein the area of each of the detector sub-pixels located below the wall surface of the grids is larger than that of each of the other detector sub-pixels in a planar view. The size of each of the detector sub-pixels not located below the wall surface of the grids is expressed as (P&#x2212;T&#x2212;L&#xd7;2)/N, where Prepresents the pitch between the grids, Trepresents the thickness of each of the grids, and N represents the number of segments formed by the detector sub-pixels between the grids.

To improve performance in Photon Counting CT, pixel miniaturization, a reduction in circuit dead time, and dealing with scattered radiation and charge sharing are important. In addition, because the number of circuits increases, a reduction in power consumption of each circuit is important. Under these constraints, circuitry that deals with the scattered radiation is provided. Each pixel includes a circuit that determines whether radiation has been detected by another, adjacent pixel at the same time, and counters that count the radiation are switched on the basis of the result of the determination. On the basis of this result, counts of non-coincident events are primarily used, and coincident counts are used after being corrected, for reconstruction data.

Radiation imaging apparatus, radiation counting apparatus, and radiation imaging method

When two detector panels are rotationally moved around the entire circumference of a region of interest and projection images of the region of interest are captured during the rotational movement, the respective detector panels are moved along the tangential direction of the rotational movement to a position where the union of the capturing ranges of the projection images captured by the respective detector panels covers the entire region of interest. The projection images captured by the respective detector panels are used to reconstruct a transaxial image of the region of interest.

Radiation image capturing device, radiation image capturing method, and nuclear medicine diagnosis apparatus

There is provided is a radiation image acquiring device which corrects a positional displacement between a collimator and a detector and obtains an image without artifacts. The device includes a detector () to measure a radiation; a collimator () including a through-hole () having one or more detectors () disposed therein and configured to limit an incident direction of the radiation; a positional displacement measuring unit configured to measure a positional displacement between the detector () and the collimator () by use of a profile of a radiation source measured by the detector () based on the radiation source disposed corresponding to a predetermined detector ().

Radiation image acquiring device

A radiation measuring device includes: a detector that detects radiation; a preamplifier that amplifies a signal outputted from the detector; a shaping amplifier that shapes the waveform of the signal outputted from the preamplifier; an A/D converter that converts the analog signal output from the shaping amplifier to a digital signal; and a digital data processing unit that calculates digital signal output from the A/D converter, wherein energy information of the radiation inputted to the detector is obtained from a pulse height of the pulse signal processed by the preamplifier and the shaping amplifier, and the pulse height of the current pulse is corrected in the digital data processing unit by performing an arithmetic operation using the pulse height information of the current pulse digitalized by the A/D converter, the generation time information of the preceding pulse, and the pulse height information of the preceding pulse.

Radiation measuring device

The purpose of the present invention is to improve energy resolving power and prevent energy resolving power from deteriorating when a thick semiconductor detection element with a wide energy range is used, in a radiation measuring device using a semiconductor detector and a nuclear medicine diagnostic device. With the present invention, the purpose is achieved by pulsed wave value correction employing the difference of (Hs&#x2212;Hf) between the pulsed wave height value Hs obtained from the slow speed shaping circuit, and the pulsed wave height value Hf obtained from the fast speed shaping circuit and normalized with respect to Hs. An even more desirable result may be obtained by employing either (Hs&#x2212;Hf)/Hf or exp(k(Hs&#x2212;Hf)/Hf), wherein k is a coefficient to be optimized, said optimization being dependent on the measurement assembly.

Radiation measurement apparatus and nuclear medicine diagnosis apparatus

A radiation imaging apparatus comprises display means for displaying an image obtained by imaging an object and light projection means for projecting a light projection mark onto the object, and displays a light projection position on the object onto which the light projection mark is projected on the image. The light projection mark is projected as a line of intersection which is perpendicular to the surface of a detector and at which two planar flat light beams visually intersect each other, and the light projection position on the image is moved according to the movements of the flat light beams. By calculating projected lines obtained by projecting the light projection lines projected onto the object by the flat light beams onto the surface and displaying the projected lines on the image, the light projection position is displayed as a point of intersection of the projected lines on the image.

Provided between a bias power supply and a radiation detector are a noise filter and a bias voltage transmitting circuit. In a state where the bias voltage is applied, the noise filter circuit operates. In a state where the bias voltage is switched on and off, the bias voltage transmitting circuit and the noise filter circuit operate. In a state where the bias voltage is switched on and off, the bias voltage transmitting circuit operates.

Radiation measuring circuit, nuclear medicine diagnosing apparatus, and method of measuring radiation

A radiation imaging system includes a detecting unit including a plurality of radiation detecting elements arranged in a plane for radiation detection, a collimator provided with through holes respectively aligned with the radiation detecting elements and opening in an entrance surface such that radiation from a specified direction is selectively made to fall on the radiation detecting elements. A second case joined to a first case fixed to the side surface of the collimator defines a holding chamber G, and a holder holding the detecting unit is placed in the holding chamber G such that spaces that allow the holder to be moved in a plane parallel to the entrance surface are formed between the holder and the second case. A position adjusting mechanism for adjusting the positional relation between the second case and the holder by moving the holder relative to the second case.

Radiation imaging system, nuclear medicine diagnosis apparatus and positioning adjusting mechanism

A PET apparatus comprises a plurality of detector units in the circumferential direction, wherein the detector unit includes a plurality of unit substrates therein, and wherein the unit substrate includes: a plurality of detectors upon which a &#x3b3;-ray is incident; and an analog ASIC and digital ASIC for processing a &#x3b3;-ray detection signal outputted by each of the detectors. The analog ASIC includes two slow systems having mutually different time constants, each of which outputs a pulseheight value. A noise determination part of the digital ASIC determines whether a relevant detection signal is an intended &#x3b3;-ray detection signal or a noise based on a correlation between the pulseheight values, and a noise counting part counts the number of times of noise determination, and a detector output signal processing control part controls the signal processing with respect to an output signal from a relevant detector based on the count.

Growing community of inventors

Hitachi, Japan

Takafumi Ishitsu