Hitachi Medical Corporation

Hitachi, Ltd.

Hitachi, Ltd. , Hitachi Medical Corporation

Masayuki Tsuneoka

Hisatake Yokouchi

Yoichi Onodera

Fumitaka Takahashi

Kouichi Koike

Takakazu Funo

Tadaaki Hirai

Yukio Takasaki

Ken Ueda

Masanori Maruyama

Keiji Umetani

Rika Baba

Takakazu Huno

A digital X-ray imaging system having an X-ray generator, an X-ray generator controller for controlling the X-ray generator, an X-ray detecting unit for detecting an X-ray transmitted through a subject, the X-ray detecting unit having an X-ray grid for shielding a scattered X-ray, a signal processor for acquiring a signal from the X-ray detecting unit and processing the signal to obtain a digital X-ray image of the subject, and a display device for displaying an image of the subject obtained by the signal processor. The system is provided with a position changing unit for changing a relative position between the X-ray detecting unit and the subject, a position change controller for controlling the position changing unit, and an imaging-sequence controller for controlling the position change controller and the X-ray generator controller. The imaging controller controls setting of each of a plurality of target imaging regions of the subject to generally a central area of an X-ray detecting plane of the X-ray detector, the X-ray detecting plane being an incident plane of the transmitted X-ray, and to set at least one imaging view field to contain an intermediate region between target imaging regions. The whole or part of a plurality of obtained digital X-ray images is used to join a single or a plurality of digital X-ray images for display.

Digital x-ray imaging system and method

An X-ray television apparatus applies an X-ray to an object to be inspected, converts the X-ray projection image of the object into an optical image by a fluorescent screen or an X-ray image intensifier, picks up the optical image by a TV camera, displays the video signal obtained by a TV monitor for fluoroscopic monitoring, and records radiograph of the object by using the video signal. Avalanche multiplication is caused on the photoconductive layer of the image pick-up tube of the TV camera so as to enable monitoring or imaging with high sensitivity at a low X-ray dose rate.

X-ray television apparatus

In a real-time digital radiographic apparatus, an image is picked up by means of a TV camera. In a fluoroscopic monitoring mode, an output of the TV camera is displayed on a display in real time. In a radiographic imaging mode, the output of the TV camera is A/D converted, subjected to a necessary image processing and held as image data for diagnosis. In the fluoroscopic monitoring mode, a beam scanning for an image pickup tube corresponding to an NTSC system is performed whereas in the radiographic imaging mode a high-density and low-speed beam scanning can be selected in which the number of scanning lines is increased and the frame rate is lowered. In order to suppressing the lowering of the maximum signal current derivable from the image pickup tube which may occur in such a high-resolution scanning, a target voltage of the image pickup tube in a high-resolution mode is changed to a value higher than a standard value of the target voltage, thereby acquiring an image which has a wide dynamic range and a high S/N ratio.

Multiple-mode scanning and beam current control x-ray TV apparatus

In an image input device, in which an image is photographed by a television camera using a plurality of operational modes having numbers of scanning lines different from each other, a video signal thus obtained is subjected to an analogue to digital conversion and a digital image signal is stored, one of a plurality of sampling clocks obtained by dividing a main clock is selected; the analogue to digital conversion is effected by using the sampling clock thus selected; and at the same time synchronization signals of the horizontal and the vertical scannings of the television camera are formed by counting the selected sampling clock.

Image input device

An X-ray television apparatus in which an X-ray image which is obtained by an X-ray image intensifier is converted to an electrical signal by a television camera. This electrical signal is converted to a digital signal and stored into an image memory, and the angiographic imaging can be performed due to a differential process of data between two X-ray images. Either one of first, second, and third operating modes in which the scanning periods and the numbers of scanning lines of the television camera differ and a fourth operating mode to obtain the X-ray images by a further low X-ray dose and to simultaneously monitor the X-ray images can be selected. Thus, proper time resolution and spatial resolution according to a desired purpose can be obtained and the beam current of the image pickup tube of the television camera which is optimum in each operating mode is set.

A television camera device for obtaining an image of high resolution by making the number of scanning lines on the target plate of an image pickup tube about twice larger than that in the television standard system and making the scanning speed of electron beam at the surface of the target plate smaller than that in the television standard system, is disclosed in which an electric field intensity in a region between the target plate and a mesh electrode (namely, the fourth grid electrode) is made greater than or equal to 5.3 KV/cm, to improve the landing characteristics of scanning electron beam, thereby preventing the occurrence of the water fall phenomenon peculiar to a slow scanning operation.

Growing community of inventors

Kashiwa, Japan

Masayuki Tsuneoka