Takara Telesystems Corp.

Telesystems Co., Ltd.

Hideyuki Nagaoka

Tsutomu Yamakawa

Koichi Ogawa

Masahiro Tsujita

Tatsuya Nagano

Daisuke Hashimoto

Akitoshi Katsumata

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 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.

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Osaka, Japan

Hideyuki Nagaoka