Takara Telesystems Corp.

Telesystems Co., Ltd.

Axion Japan Co., Ltd.

Tsutomu Yamakawa

Koichi Ogawa

Masahiro Tsujita

Tatsuya Nagano

Akitoshi Katsumata

Hideyuki Nagaoka

Daisuke Hashimoto

Kazuhide Kitou

Yasuo Harata

Takashi Sue

Hisatoshi Aoki

Kazuyuki Araki

An X-ray tomographic imaging apparatus includes an X-ray and a direct conversion type of detector. The X-ray tube and the detector are supported by the support means so as to be rotatable along curved orbits mutually independently. Under instructions from a computer, scans and image reconstruction are performed. The X-ray tube and the detector are moved along the orbits mutually independently so that X-ray beams are always transmitted through a desired tomographic plane of an object at desired angles. Acquired frame data are used to produce a panoramic image of the plane, while the frame data and the panoramic image are used to produce a tomographic image in which structural components of the object are optically focused and distortions caused due to differences in X-ray paths are suppressed. The apparatus can be used as devices for dental, medical diagnosis and nondestructive inspection, and can have a CT imaging function.

X-ray tomogram imaging device

There is provided a panoramic imaging apparatus which serves as a radiation imaging apparatus. The panoramic imaging apparatus includes an X-ray tube radiating an X-ray as a radiation, a detector outputting digital-quantity frame data corresponding to an incident X-ray, and moving means moving the pair of X-ray tube and the detector relatively to an object. The apparatus further includes means for acquiring the frame data from the detector during movement of the X-ray tube and the detector, and means for optimally focusing a portion being imaged of the object using the acquired data and producing a three-dimensional optimally focused image in which the real size and shape of the portion being imaged are reflected.

Radiation imaging apparatus and imaging method using radiation

In the imaging space provided by a panoramic imaging apparatus, a phantom is arranged. The phantom is located to a predetermined tomographic plane and includes markers which image known positional information with an X-ray beam. The X-ray beam from an X-ray source is acquired as X-ray transmission data by a detector, and a panoramic image is produced using the data. Based on known positional information of the markers and information of marker positions in the panoramic image, distance information (Rs, Rd) between the X-ray tube and the detector and height information (B) of the X-ray tube to the detector are calculated. From this calculated results and the acquired data, parameters (&#x394;x/&#x394;Fi, &#x3b8;, &#x394;&#x3b8;/&#x394;Fi, D, A, CX, CY) defining positional relationships among the X-ray tube, the detector, and the tomographic plane are calculated such that amounts of changes in the position connecting the X-ray tube and the detector are considered in the parameters. This allows the parameters to be calibrated for 3D image reconstruction.

Radiation imaging apparatus and phantom used for the same

An X-ray detector is provided with a plurality of modules each having a plurality of detection elements each composing a pixel, in which the detection elements convert incoming radiations to electric data depending on amounts of the radiations. The plural modules are mutually adjacently arranged on the same surface with a gap having a known width formed therebetween, such that the modules are arranged along at least one of a first X-axis and a first Y-axis, wherein the radiation detector is given a scan direction which is set along one of the first X- and Y-axes and the first Y-axis is perpendicular to the first X-axis. The plural detection elements of each module are two-dimensionally arranged along a second X-axis and a second Y-axis which are set obliquely to the first X-axis and the first Y-axis respectively and which are perpendicular to each other.

Radiation detector, and radiation imaging apparatus provided with detector

There is provided a calibration apparatus used for a photon counting type of radiation detector. In this apparatus, a radiation condition of a radiation is set such that particles of the radiation (X-rays) which are incident on a plurality of detection modules are piled up over each other at a probability which is equal to or less than a predetermined value. Under the setting of this radiation condition, detection sensitivities for the radiation are made uniform among the plurality of detection modules. Using this uniformed result, the detection sensitivities for the radiation are further made uniform every channel of each of the pixels formed by circuit groups including the plurality of detection modules, discrimination circuits and data calculation circuits and every discrimination circuit in each channel.

Apparatus for calibrating photon-counting type of radiation detector and method of calibrating the same

A radiation detecting apparatus includes a radiation detector, a power source, a current detector, and a bias voltage adjuster. The detector includes a semiconductor layer having a compound semiconductor directly converting incoming radiation photons to electric charges and a pair of electrode layers stacked individually on both surfaces of the semiconductor layer. One layer of the paired electrode layers has plural collecting electrodes which enable the semiconductor layer to have one-dimensionally or two-dimensionally arrayed pixels. The power source applies a direct-current bias voltage between the electrodes such that the electric charge is collected to one electrode of the electrodes. The current detector detects current supplied from the power source when the power source applies the bias voltage between the electrodes. The bias voltage adjuster changes a value of the bias voltage applied by the power source depending on a value of the current detected by the current detector.

Method and apparatus for supplying bias voltage to radiation detector

A radiation imaging apparatus is provided. The apparatus has moving means moving a pair of an X-ray tube and a detector relatively to an object. The apparatus further has means which acquire digital frame data outputted from the detector. The frame data are acquired from the same portion being imaged of the same object at different time points. The apparatus has means which use the frame data to produce a plurality of three-dimensional optimally focused images at the respective time points, an actual position and shape of the portion being imaged being reflected in the images, and means which estimate changes of the plural three-dimensional optimally focused images.

A panoramic imaging apparatus functionally includes an image processing apparatus. In this apparatus, two planar images are produced, which are subjected to registration. A registration process is applied to overall areas of two planar images based on curves decided from positions designated on the two planar images respectively. The positions on each of the planar images are aligned along a straight line, both straight lines corresponding to each other in a horizontal direction, and a scale factor for the registration is changed position by position on the straight lines. One of the two planar images is searched for a match of each local region of the other planar image, to any of regions of the one planar image, and images of the matched regions are re-produced to produce a planar image. The difference information is calculated between the planar images.

Image processing apparatus and image processing method

A panoramic imaging apparatus is provided, which is able to freely display a focus-optimized internal structural image of the tooth row depending on a position using image data acquired by only one-time X-ray panoramic imaging from an arbitrary section along a patient's tooth row. The panoramic imaging apparatus comprise an X-ray source () and a detector () outputting a digital electrical signal depending on an incident X-ray at a constant frame rate. This apparatus further comprises means () for moving a pair of the X-ray source and the detector around an object in a state where the X-ray source and the detector are opposed to each other with the object located therebetween, means () for sequentially storing, as frame data, the electrical signal outputted by the detector, means () for producing a panoramic image of a desired section of the object based on the frame data, and means () for producing a partial sectional image using the frame data, the partial sectional image being an image of a partial region specified on the panoramic image and being focused depending on a desired position in an imaging space.

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Osaka, Japan

Tsutomu Yamakawa