Abstract: In a two-dimensional radiation detector of the invention, a semiconductor layer for converting a radiological image or light image converted therefrom to a picture image of charges by sensing X-ray, and a switching element matrix are integrally formed. A bias electrode common to a signal electrode of the semiconductor layer is connected to a bias power source through a switch or a resistance. An electric current flowing through the bias electrode from the bias power source is detected by a detector, and supplied to a control circuit. The control circuit compares a detected value supplied from the detector with a threshold value, and turns off the switch when the detected current value reaches the threshold value to shut off application of the bias voltage to the bias electrode.

Abstract: The rotary cathode X-ray tube equipment of present invention is constructed so as to permit radiation of X-ray from all directions with respect to the whole circumference of a subject, and is used for x-ray CT. The equipment of the invention is constructed to prevent an X-ray radiation window 40 of a low strength from being influenced by atmospheric deformations of a vacuum vessel 1 or by machining and assembling errors, for example by using a joint portion disposed between the X-ray radiation window and an inner ring and having both a surface perpendicular to a rotational axis of a rotary member and a cylindrical surface parallel to the rotational axis, a face seal formed on the surface of the joint portion perpendicular to the rotational axis, and an axial seal formed on the cylindrical surface of the joint portion parallel to the rotational axis.

Abstract: The rotary cathode X-ray tube equipment of the present invention is constructed so as to permit radiation of X-ray from all directions with respect to the whole circumference of a subject, and is used for x-ray CT. The equipment of the invention is constructed to prevent an X-ray radiation window 40 of a low strength from being influenced by atmospheric deformations of a vacuum vessel 1 or by machining and assembling errors, for example by using a joint portion disposed between the X-ray radiation window and an inner ring and having both a surface perpendicular to a rotational axis of a rotary member and a cylindrical surface parallel to the rotational axis, a face seal formed on the surface of the joint portion perpendicular to the rotational axis, and an axial seal formed on the cylindrical surface of the joint portion parallel to the rotational axis.

Abstract: An X-ray image pickup tube converts a transmitted X-ray image into electric signals. The pickup tube includes a target structure having a fluorescent element, and a translucent conductive film for receiving a high voltage, with a photoconductive film laminated thereupon. The fluorescent element receives transmitted X rays in a two-dimensional distribution, and converts them into visible rays in a two-dimensional distribution. The translucnet conductive film is optically coupled to a surface of the fluorescent element opposite from an X-ray incident surface thereof. The photoconductive film includes an amorphors semiconductor layer which converts the visible rays transmitted in a two-dimensional distribution through the translucent conductive film, into electric charges in a two-dimensional distribution, and which multiplies the electric charges in the two-dimensional distribution based on electric fields formed by the high voltage applied to the translucent conductive film.

Abstract: The rotary cathode X-ray tube equipment of the present invention is constructed so as to permit radiation of X-ray from all directions with respect to the whole circumference of a subject, and is used for x-ray CT. The equipment of the invention is constructed to prevent an X-ray radiation window 40 of a low strength from being influenced by atmospheric deformations of a vacuum vessel 1 or by machining and assembling errors, for example by using a joint portion disposed between the X-ray radiation window and an inner ring and having both a surface perpendicular to a rotational axis of a rotary member and a cylindrical surface parallel to the rotational axis, a face seal formed on the surface of the joint portion perpendicular to the rotational axis, and an axial seal formed on the cylindrical surface of the joint portion parallel to the rotational axis.