Hitachi Medical Corporation

Takakazu Funo

Hisatake Yokouchi

Yoichi Onodera

Masayuki Tsuneoka

Tadaaki Hirai

Yukio Takasaki

Kouichi Koike

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

Growing community of inventors

Nishitama, Japan

Takakazu Funo