Abstract: The serial communication device capable of reducing the load on the CPU is provided for a system using the serial communications such as the car navigation system. The attention is focused on the control method of the serial communication, in which a DMA controller is used for the data reception in the serial communication, and a number larger than the number of data received at a time is set in advance as the number of transfers of the receive DMA controller, and further, the function to generate the timeout interrupt when data is not received for a certain period is added to the serial interface, so that the serial communication can be controlled and performed without applying the load on the CPU.

Abstract: The serial communication device capable of reducing the load on the CPU is provided for a system using the serial communications such as the car navigation system. The attention is focused on the control method of the serial communication, in which a DMA controller is used for the data reception in the serial communication, and a number larger than the number of data received at a time is set in advance as the number of transfers of the receive DMA controller, and further, the function to generate the timeout interrupt when data is not received for a certain period is added to the serial interface, so that the serial communication can be controlled and performed without applying the load on the CPU.

Abstract: A digital radiography system having an X-ray source irradiating an object to be inspected with X-ray, an X-ray image intensifier tube which receives the X-rays which pass through the object and converts the received X-rays into an optical image, a video camera which picks up the output image and has different modes, an optical system including a plurality of lenses and disposed between the X-ray image intensifier tube and the video camera, an image processor which converts an output from the video camera into a digital image data, and an image display for displaying an X-ray image by reading out the digital image data from the image processor.

Abstract: A digital radiography system having an X-ray source irradiating an object to be inspected with X-ray, an X-ray image intensifier tube which receives the X-rays which pass through the object and converts the received X-rays into an optical image, a video camera which picks up the output image and has different modes, an optical system including a plurality of lenses and disposed between the X-ray image intensifier tube and the video camera, an image processor which converts an output from the video camera into a digital image data, and an image display for displaying an X-ray image by reading out the digital image data from the image processor.

Abstract: A digital radiography system obtaining x-ray images of a patient body through an X-ray image intensifier tube and a video camera optically coupled with the X-ray image intensifier tube. The diameter of an input imaged size of the X-ray image intensifier tube is ranged from 254 to 457 mm, the diameter of an output image size of the X-ray image intensifier tube is ranged from 50 to 90 mm, and the ratio of the diameter of the output image size against the diameter of the input image size is ranged from 4 to 8.

Abstract: A digital radiography system obtaining X-ray images of a patient body through an X-ray image intensifier tube and a video camera optically coupled with the X-ray image intensifier tube. The diameter of an input imaged size of the X-ray image intensifier tube is ranged from 254 to 457 mm, the diameter of an output image size of the X-ray image intensifier tube is ranged from 50 to 90 mm, and the ratio of the diameter of the output image size against the diameter of the input image size is ranged from 4 to 8.

Abstract: In order to image an object larger than a field of view for observation, imaging is effected by dividing it into several times and pictures thus imaged are synthesized to constitute a whole image. In order to image several times, only a detecting unit is moved and an X-ray source is substantially fixed with respect to the object. Images thus obtained include a common part of the object and are joined so that the common part are overlapped on each other. In case where an image pick-up tube is included in the detecting unit, the image pick-up tube is made operable, after a period of time necessary for attenuation of microphonic noise has lapsed, measured from a point of time where the detecting unit has been stopped.

Abstract: An X-ray radiography method and apparatus in which a phantom such as a chart having elements arranged in predetermined positions is irradiated with X-rays and an X-rays detection unit detects signals thereof. An image of the chart is obtained and a center position of each of the elements in the image of the chart is obtained as well as for those elements which are not within the imaging field of view. Pixel positions for a distortion free image is obtained and a transform table is prepared making each of the pixel positions in the image of the chart correspond to each of the pixel positions in the distortion free image. A plurality of digital images of a subject to be examined are obtained and the digital images are corrected in accordance with the transform table. The corrected digital images are then joined together and a digital image is displayed, wherein common portions in the corrected images are in accordance with each other.

Abstract: 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.

Abstract: An X-ray imaging apparatus is constructed with a combination of an X-ray image intensifier, a relay optical system, and a video camera with avalanche multiplication camera tube. The video camera is controlled by an image acquisition circuit, a synchronizing signal generation circuit, and an applying voltage control circuit. The applying voltage control circuit for controlling the voltage to be applied to the video camera with avalanche multiplication camera tube controls the applying voltage on the basis of image data in an image memory so that the gray scale level of a detected visible image is corrected.

Abstract: An X-ray fluorograph and radiograph apparatus including an X-ray television camera having an avalanche multiplication operation type image pick-up tube having an input/output characteristic in which increment of an output reduces gradually against increase of dose of incident X-rays and a unit for setting X-ray latitude and a multiplication factor of an image pick-up tube to optimum values for inputted radiograph conditions by controlling a voltage value applied to the image pick-up tube and a value of a stop of an optical system, and making it possible to obtain X-ray latitude at 1,000 or more.

Abstract: A real-time digital radiography system operates to introduce a X-ray image on a real-time basis and process the image for clinical diagnosis. The system provides for additional inputs, for example, clinical information material, which are also subject to digital image conversion. The system is designed to connect several TV cameras to an A/D converter which digitally converts the produced image to digital information, with one of the TV cameras for imaging the output image of an X-ray image intensifier, and the output of the one TV camera is selectively connected to the A/D converter. The output image of the X-ray image intensifier and other output images produced by separate TV cameras are connected to the A/D converter through a switching apparatus, and subsequently the digital output is processed.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: In a film image reading out device, in which one surface of a film, where images are recorded, is scanned repeatedly with a laser light beam along a scanning line and images are read out by detecting continuously light, which has passed through the film, while moving the film with a low speed in the direction, which is perpendicular to the scanning line, a light diffusing member is disposed closely to the surface opposite to that of the film scanned with the laser light beam and the optical density of the film is detected continuously by leading transmitted and diffused light to a photodetector by means of a bundle of optical fibers.

Abstract: A circuit for correcting a variation in phase of a train of clock pulses detected from a pattern of a coding disc of a rotary encoder which detects the rotation angle of a rotating shaft, comprises an ROM in which data for correction of a phase variation corresponding to the rotation angles of the coding disc are preliminarily stored. The correction data are read from the ROM by designating addresses of the ROM by means of the counter which counts up a train of clock pulses from the rotary encoder before the clock pulse train is subjected to correction. The clock pulses are phase-modulated by the correction data from the ROM to provide a corrected train of clock pulses which correctly represent the rotation angles of the rotating shaft.