Abstract: An NMR imaging apparatus, wherein a 180.degree. RF pulse is applied shortly after the termination of the 90.degree. RF pulse, and wherein after such 180.degree. pulse application, to collection of spins and after collection of spins to dispersion of spins are sampled asymmetrically, whereby Fourier transformation takes place by interpolating missing data on a Fourier plane, and by operating on the data, image is accurately reconstructed. The novel pulse sequence improves the S/N ratio and reduces deterioration of images.

Abstract: The present invention relates to a CRT multiformat camera which photographs CRT images onto photographic media of either film or photoprint in photographic conditions automatically set according to a selected photographic media type and has a feature of including photographing media discriminator (1) which discriminates between photographic media, and photographing condition setting device (4) which sets photographic conditions to the camera and/or the CRT display unit according to the discriminating signal of said photographing media discriminator.

Abstract: In measuring a number of echo signal, which normally attenuate chronologically, in a single pulse sequence, such as in multi-echo method or a multi-slice method, each echo signal is received and suitably amplified by a reception amplifier having predetermined levels of gain for different time periods during which the successive echo signals are processed such that the echo signals received at a data collection unit are all of substantially the same amplitude regardless of where they appear in the time sequence. The predetermined levels of gains are obtained by false scanning prior to actual image scanning and calculation and storing in a memory. As a result, the echo signals can be received within a dynamic range which is smaller than using the conventional system.

Abstract: An NMR imaging domain is required to have a uniform distribution of static magnetic field. However, it is very difficult to generate a uniform magnetic field for an entire imaging domain, which is usually a spherical domain. The invention advantageously, exploits the requirement that to obtain imaging the static magnetic field need only be uniform as the slicing part. Thus, sufficient uniformity of static magnetic field is obtained in the invention by providing one or more shim coils to a static magnetic field generating coil and selectively controlling current to be applied to each shim coil in relation to data defining the imaging domain.

Abstract: The equipment in this invention provided with an internal signal checking means configured in a combined use with signal processing and display means commonly furnished to an ultrasound diagnostic equipment stores various internal signals and in said equipment by selectively inputting them through a multiplexer into a video memory also used for receive echo signal storage, and said internal signals stored are displayed on a screen of a display means of said equipment as an image or they are evaluated by a processor in said equipment to perform internal signal checking.

Abstract: A method and apparatus are disclosed for nuclear magnetic resonance imaging utilizing the Fourier transform imaging scan sequence, with measurement data being obtained from which the offects of variations in the static magnetic field are eliminated. The method and apparatus are characterized by measurement of view data G(k,t) for a body which is under diagnosis under the condition that there is a specific value of twist of spin phase within the body, in a specific direction, measurement of the view data G(-k,t) for the body which is under diagnosis under the condition that the value of twist of the spin phase within the body is equal in amount and of opposite direction to the aforementioned value of twist of spin phase, with the time which elapses between the measurements of G(k,t) and G(-k,t) being made sufficiently short that any change in the static magnetic field occurring therein can be ignored, deriving from the view data G(k,t) and G(-k,t) the data G(k,t.sub.0) and G(-k,-t.sub.

Abstract: An object which can provide a reference for measuring the intensity of a primary magnetic field, is positioned in the vicinity of a subject being examined. A variation in the primary magnetic field intensity is detected, based on a frequency shift of data observed of the object, and is used to control the primary magnetic field intensity, or reference frequency for phase detection, or to correct image data. In this manner image quality is prevented from being degraded due to the variation of the primary magnetic field intensity.

Abstract: The equipment in this invention provides an ultrasound diagnostic equipment with a matrix switch checking means configured in a combined use with means commonly furnished to said device heaving a built-in test sequencer, whereby taps on the delay line is selected in due order from one end of said taps for each channel of the matrix switch to input a checking signal to that channel from a transducer circuit every time these taps are selected; as a result a signal obtained from the delay-line output terminals is shown on a display screen of a display device as a mimic echo signal to determine the presence or absence of any fault of switching elements in the relevant channel of the matrix switch based on a mimic echo image pattern shown on the display screen.

Abstract: The static magnetic fields of an NMR imaging apparatus should be maintained constant in intensity in order to obtain satisfactory NMR images. Coils used to generate the static magnetic fields, and the supporting frames therefor, are subject to heat expansion due to changes in the temperature, which causes fluctuations in the intensity of the generated static magnetic fields. In the invention, the temperatures of the coils, frames, atmosphere and cooling water, and the amount of cooling water, are detected, and the energizing current for the static magnetic field coils is selectively controlled, based on the detected quantities, to thereby maintain constant the intensity of the generated static magnetic fields.

Abstract: An NMR data processing method for use with an NMR tomograph, wherein signals, located in a period before and after an NMR signal to be sampled and containing substantially none of the NMR signal component, are measured as offset data for each view, so that even the offset slightly fluctuating in the view can be corrected for the NMR signal, on the basis of that data.

Abstract: A radiation CT system packs projection data and reads the data in a DMA mode, and separates the packed data into individual data items through format conversion when the data are to be processed. The system has a memory for storing raw projection data and processed image data for one full image. With this arrangement, a high speed processing program for image reconstruction can be executed exclusively for image reconstruction immediately after scanning operation has started. During image reconstruction processing, no data transfer to and from an external memory is performed, thereby to reduce the period of time required for image reconstruction after data have been collected.

Abstract: Two different CT images are stored respectively in a primary image memory and a secondary image memory. For image display, the secondary image is inset in a desired rectangular region in the main image memory so that the two images can simultaneously be displayed. The data for the two images to be displayed can be independently subjected to various types of processing in real time, such as window or level processing, blinking for flashing displayed image data pixels in a particular CT value zone, and reverse video operations.

Abstract: A phased array sonar is arranged to obtain an image in a wide field of view beyond a normal angle of view. In an angle of view beyond the normal angle of view, the number of active transducer elements, which are simultaneously energized, is reduced, as the angle of view is increased, and at the same time, the amplification factor for the echo signals is increased.

Abstract: In ultrasonic transmission from and reception by an array probe in a phased array sonar, when an ultrasonic beam is directed substantially in front of the array probe, an ultrasonic wave having a high center frequency f.sub.o, or a bandwidth extending into higher frequencies, is transmitted and/or received in order to insure a high image resolution. When the ultrasonic beam is steered sideways, an ultrasonic wave having a lower center frequency f.sub.o, or a higher frequency range cutoff in relation to a steering angle .theta., is transmitted and/or received in order to increase the angle at which grating lobes are generated and hence prevent such grating lobes from entering the angle range of the field of view.

Abstract: A coil assembly comprises four coils for generating a static magnetic field in an NMR imaging apparatus, wherein the dimensions of the coils are selected so that the flatness of the cross section of the coils, the current turns ratio, and the radius ratio, are within certain limits. The assembly so constructed produces highly uniform magnetic field, is small in size, and light-weight, and consumes a lower amount of power, and can be manufactured inexpensively.

Abstract: A table mechanism suitable for use in a tomographic system, such as an X-ray computerized tomograph, has a table movable upwardly and downwardly by a parallel link mechanism. The distance of horizontal movement of a cradle on the table can be automatically compensated for, dependent on an angle of angular movement of the parallel link mechanism, while holding the cradle and a gantry, relatively positioned in a constant relation. A side of the parallel link mechanism is covered with a cover mechanism having a relatively small area.

Abstract: A phased-array receiver used in an ultrasonic diagnostic apparatus or the like for appropriately varying the phases of the output voltages from transducer elements receiving ultrasonic waves and for summing these voltages to change the directional or other characteristics of ultrasonic waves. The receiver is equipped with a plurality of blocks each comprising a tapped delay line and a crosspoint switch. The crosspoint switch is capable of selecting any desired one of various delay periods of the delay line. The receiver can perform all types of scans ranging from linear scan, intermediate scan, dynamic focusing scan, to sector scan.