Hamamatsu-photonics K.k.

Hamamatsu Photonics Kabushiki Kaisha

National Institute of Radiological Sciences

National Institutes for Quantum and Radiological Science and Technology

National Institute of Radiological Sicences

Mitsuo Watanabe

Taiga Yamaya

Tomohide Omura

Takahiro Moriya

Eiichi Tanaka

Kenshi Fukumitsu

Takaji Yamashita

Hiroyuki Okada

Hiroshi Uchida

Hideo Murayama

Ryosuke Ota

Takayuki Obata

Naoko Inadama

Hideaki Tashima

Fumihiko Nishikido

Keiji Shimizu

Mikio Suga

Ryoko Yamada

Kazuyuki Saito

Toshihiko Sawai

Nobuyuki Hirai

A PET device includes detectors including detector signal processing units and a data processing circuit configured to acquire a gamma ray generation position. The detector signal processing unit includes a Compton cone estimating unit configured to estimate incidence directions of gamma rays detected by a pair of detectors as a first and second Compton cones. The data processing unit includes: a coincidence acquiring unit; a scattering surface estimating unit; an intersection line determining unit; an intersection point determining unit; and a gamma ray generation position.

PET device and method of acquiring gamma ray generation position using scattered coincidence with PET device

A scintillator array including a plurality of scintillators, an optical detector array corresponding to the scintillators, an AD conversion unit configured to convert an analog signal output from each optical detector into digital data, and a position detection processing unit configured to specify a position of the scintillator on which the radiation is incident are provided. If there are two different pieces of digital data at the same time, the position detection processing unit determines that radiation is incident on two scintillators when energy value data of the two pieces of digital data is greater than an energy value of a Compton edge and specifies the address of the scintillator on which the radiation is incident by comparing the energy values of the two pieces of digital data when at least one of the two energy values is less than the energy value of the Compton edge.

Radiation position detector, PET device, and recording medium

An inclined PET device is provided in which the cut plane of a detector ring upon which a plurality of PET detectors are disposed is inclined so that it does not intersect perpendicularly with the long axis of a bed that carries a subject to be examined and in which an open space that passes through the bed in a direction perpendicular to the long axis thereof is formed, in order to enable access to the subject to be examined. The PET detectors are disposed and stacked in a direction parallel to the long axis of the bed. Thereby, the number of PET detectors is reduced and device cost is reduced, while the detector ring as well as the device can be miniaturized. At the same time, the open space that passes through the bed in a direction perpendicular to the long axis can be preserved.

Inclined pet device and pet combined device

In the integrated PET/MRI scanner provided with an RF coil for MRI and a plurality of PET detectors in the measuring port of the MRI scanner, the PET detectors are disposed with spaces therebetween and at least the transmitting coil elements of the RF coil for MRI are disposed between adjacent PET detectors. Here, the PET detectors are disposed in the circumferential direction of the measuring port with spaces therebetween and the transmitting coil elements are disposed in the axial direction of the measuring port. Alternatively, at least some of the PET detectors are disposed in the axial direction of the measuring port with spaces therebetween and the transmitting coil elements are disposed between adjacent PET detectors. The PET detectors can be DOI-type detectors capable of detecting position in the depth direction.

Integrated PET/MRI scanner

A three-dimensional position-sensitive radiation detector is provided which has a three-dimensional array of photodetectors disposed on the surface of a scintillator block and which is capable of three-dimensionally identifying the position of light emission at which radiation has been detected within the detector. The three-dimensional position-sensitive radiation detector includes: a scintillator block including a central portion which restricts the direction of diffusion of light so as to direct the light in three axial directions and which has an optically discontinuous region, and an outer portion which is disposed on the outside of the central portion and which does not restrict the direction of diffusion of light; and photodetectors disposed on at least two outer circumferential surfaces of the scintillator block. The detector identifies three-dimensionally the position of light emission, thereby preventing deterioration in position discrimination performance even when inner scintillator elements are smaller than the photodetectors.

Three-dimensional position-sensitive radiation detector and method of identifying radiation detected positions therein

An object of the present invention is to provide a radiation site detector which can detect a position of an incident scintillator with high precision by excluding the effect of Compton scattering. The radiation site detector is provided with a scintillator array having a plurality of scintillators into which a radiation is made incident, and a photodetector for converting scintillations occurring in the scintillators to independent photoelectric conversion signals to output them. A level of each of photoelectric conversion signals output from a specific scintillator to be judged whether the radiation has been incident thereinto, and from a plurality of scintillators around the specific scintillator, is compared with a plurality of threshold values different from one another so as to determine whether the levels are within or outside a window defined by the threshold values. Then, it is judged whether the above specific scintillator is a scintillator into which the radiation has been incident based on the characteristics of a signal pattern obtained in the above comparison.

Radiation site detecting apparatus

A position detector detects a light incident position on one of a plurality of scintillators with a photomultiplier having a number of anodes smaller in number than the scintillators and with a simple circuit configuration. A plurality of anodes are provided in one-to-two or one-to-three correspondence to the plurality of scintillators. An anode receiving photoelectrons is detected from a specific output produced from one of a plurality of first group comparators. Further, either one of two anodes adjacent the detected anode at which the major part of the photoelectrons are received is determined from the outputs of second comparators, whereby one of the plurality of scintillators can be identified.

Position detector using two dimensional multi-anode photomultiplier tube

A photomultiplier tube has a multi-anode array consisting of a first group of anodes arranged in the Y-direction and a second group of anodes arranged in the X-direction in the form of a plurality of rows. Each of the anodes of the first group for detecting a receiving position of photoelectrons in the Y-direction contains the associated anodes of the second group for detecting the receiving position of photoelectrons in the X-direction so as to form an empty space therebetween.

Multi-anode array photomultiplier tube

A data correcting device is intended to be used with a CT apparatus for obtaining a tomographic image with a subject holding means being adapted to be slidable into or out of the tunnel in a gantry. The device includes a body movement sensor for detecting a movement of a subject under examination; a body movement data processing unit for converting body movement data from the body movement sensor into address correcting data; a tomographic data processing unit for processing tomographic data obtained in the gantry; an address converting unit for correcting the address of the tomographic data with the address correcting data; and a memory for storing data.

Data correcting device for use with computed tomography apparatus

A two-dimensional incident position detector device for radiation, the device comprising a detector array including a plurality of detection cells in two-dimensional arrangement, and a comparator circuit for comparing an output from a noticed detection cell with outputs from all detection cells adjacent to said noticed cell, whereby a position of the noticed cell is decided as an incident position of light or radiation when the output from the noticed cell is larger than the outputs from all adjacent detection cells.

Two-dimensional incident position detector device for light or radiation

An optical window comprises a plurality of glass members and a plurality of reflective members each being formed between the adjacent glass members. Each reflective member is made of a glass medium which is the same as the glass member and grain regions made of a material having large reflectance and interspersed in the glass medium. A radiation position-sensitive detector comprises a scintillator, the optical window of the invention, and a multi-anode type photomultiplier tube which has a plurality of photomultipliers.

Optical window and radiation position-sensitive detector using the same

A two dimensional weak emitted light measuring device for determining and indicating the intensity and location of single photon light emitted from a specimen excited by radiation. The device includes an incident position detecting tube and a calculating unit for generating coordinates of the incident radiation and a data processing unit for producing specimen identification data in response to the coordinates and timing signals.

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Hamamatsu, Japan

Mitsuo Watanabe