Abstract: An image correcting apparatus for correcting distortion appearing in an image produced by electron beam scanning in a SEM under the influence of electric, magnetic and mechanical vibrations through arithmetic operations for eliminating the distortion. Installation of electric shield, magnetic shield and vibration-damping structure is thus rendered unnecessary.

Abstract: In order to permit the detection of a respiratory motion and an imaging synchronized with the respiration by an NMR imaging apparatus itself without any special hardware, a sequence for detecting the respiratory motion is repeated for a short time immediately before the measurement of an image signal to detect the position and speed of the respiratory motion, and a desired image signal is measured in synchronism with the detected position. Alternatively, the respiratory motion is detected immediately after the measurement of an image signal, and the measured image signal is corrected in accordance with the detected amount to obtain a desired image signal synchronized with the respiration.

Abstract: A magnetic resonance imaging method and a device for realizing the same for obtaining a magnetic resonance image having corrected phases, wherein the device comprises a construction for generating a static magnetic field, gradient magnetic fields and a radio-frequency magnetic field, irradiating an object to be tested with these magnetic fields and detecting nuclear magnetic resonance signals coming from the object to be tested; a sequence-controlling portion controlling the irradiation of the object to be tested with the gradient magnetic fields and the radio-frequency magnetic field and the detection of the nuclear magnetic resonance signals; and a processing device for reconstructing complex image data on the basis of the nuclear magnetic resonance signals thus detected.

Abstract: A magnetic resonance signal is detected at a plurality of different periods of time in accordance with the phase shift of a plurality of chemical shift components while varying the intensity of a gradient magnetic field with time, a plurality of magnetic resonance signals thus obtained are used for estimating a magnetic resonance signal due to only a predetermined chemical shift component, the phase rotation of the predetermined chemical shift component is corrected in the estimated resonance signal, and further a blur due to chemical shift components other than the predetermined one is corrected to obtain a tomogram formed of only the predetermined chemical shift component. Alternatively, one measured resonance signal is modified by an image construction algorithm peculiar to each of a plurality of chemical shift components, to obtain tomograms corresponding to the chemical shift components.

Abstract: In order to extract correctly an intended region by correcting the distortion of two images due to different time points of observation, an emphasis factor which depends on the standard deviation of the image gray value within the intended region is evaluated, and the intended region for registration is selected after adaptive filtering with characteristics determined by the emphasis factor.

Abstract: In an nuclear magnetic resonance imaging system for acquiring a tomographic image of an object of interest at a high speed by use of time-varying gradient magnetic fields, a weighting factor is used in reconstructing an image through the calculation of a correlation of data of a detected nuclear magnetic resonance signal with data of a reference signal, thereby controlling the point spread function and/or the signal-to-noise ratio in each point on the reconstruction image. Also, the effect of relaxation, chemical shift and/or static magnetic field inhomegeneity, which would otherwise degradate the image quality, can be corrected. Further, a velocity of the object of interest at each point on the reconstruction image can be measured.

Abstract: To display the information, as an image, regarding the moving portion of the object without the aid of the doctor, the image is reconstructed on the basis of the observed NMR signal and the image phase information is calculated from the image intensity information derived from the reconstructed image, and the phase information calculated is displayed as the image.

Abstract: A slice selection gradient magnetic field used in a pulse sequence for generating a spin echo signal is applied in such a fashion that its polarity at the time of a 90.degree. pulse becomes opposite to the one at the time of 180 .degree. pulse, in order to expand a dynamic range of blood flow speed measurement. When the blood flow speed contains a component in a slice vertical direction, the gradient magnetic field in the slice vertical direction is adjusted so that the phase changes of two sets of flow encoded pulses contained in the slice vertical direction are opposite to each other.The flow speed in the direction of the readout gradient magnetic field, which is a lateral direction of the slice plane, is purely measured by cancelling influences of the flow in the slice vertical direction.

Abstract: A method and system for measuring sectional shape to system the sectional shape of a subject on a plane that includes a direction that couples light sources or detectors, relying upon intensities of the same subject taken or irradiated from one direction wherein a calculation is carried out using a function that is not affected by the change of surface material of the subject in order to find a gradient component of a surface element in the direction which couples the light sources or the detectors, and the sectional shape of the subject on a plane that includes the direction coupling the light sources and the surface element, is determined relying upon the gradient component, making it possible to correctly obtain the sectional shape even when there exist different materials on the subject. Distortion in the measured result caused by the shadow of the surface topography is corrected by repeating the procedure; i.e.

Abstract: To measure a line width of a linear portion of a digital image maintaining a precision finer than a picture element, a digital linear cursor pattern represented by digital picture elements is generated, the pattern is inclined with respect to the horizontal direction by an angle which maximizes the measuring precision, and the pattern is fitted to a linear portion to be measured, to thereby measure the width of a line.

Abstract: A method for imaging a three-dimensional moving object is disclosed, by which a static magnetic field, gradient magnetic fields and high frequency magnetic field are generated; a nuclear magnetic resonance signal due to them coming from an examined object is detected; and various sorts of operations including image reconstruction are effected, starting from the signal thus detected so that the speed of moving object moving in any three-dimensional direction, independently of the slice direction, can be measured by one imaging.

Abstract: In an unsharp masking processing for sharpening images such as radiographic images, an emphasizing coefficient of an image and parameters for real-time change of picture quality are set interactively. The entire image is divided into a plurality of regional images and filtering optimized for each pixel image is effected using a standard deviation computed for each regional image and a density difference between pixel images.

Abstract: Method of determining stereoscopic geometry of an object through photometric stereoscopic measurement with high accuracy. Three or more images of the object picked up in a same fixed direction by varying the state of light sources are derived. Relationships among the images are corrected so that an evaluation function determined by making use of redundancy of the images assumes a minimum value, to thereby prepare a reflectance map to be used in determining orientations of surface elements of the object. Through integration of the orientations, the surface shape of the object is determined. The method is applicable to the image processing in a scanning electron microscope.

Abstract: In order to make an accurate display possible even in case image data having been subjected to a Fourier transformation have negative values, the sampling timing deviations of measured signals having phase errors based on various factors are detected from the gradient of the linear components of the image data having been subjected to the Fourier transformation, and the density values of the image having the detected timing deviations corrected are displayed.

Abstract: A sample surface structure measuring method using a scanning type electron microscope featured by scanning the sample surface by an electron beam incident from above the sample surface; measuring the amount of the secondary electrons discharged according to the three-dimensional structure of the sample surface by the scanning; and determining the three-dimensional structure of the sample surface from the amount of the secondary electrons measured based on a relation existing between the predetermined three-dimensional structure and the amount of the secondary electrons discharged.

Abstract: A stereoscopic measuring method and system for measuring the sectional shape of a step formed object such as a semiconductor element carrying a resist and wiring on a wafer. The method and system comprises the steps of means for detecting the images of the step formed object from at least two directions so as to form pictures corresponding to the images detected from different directions, determining the distances D between the upper and lower edges of a step in respective pictures; determining the angles .theta. of inclination of the edge lines with respect to the axis of the pictures, determining the angles of inclination of the standard plane fixed to the step formed object with respect to the viewing directions, and determining, as significant factors of the shape to be determined, the height H and width W of the step formed object.

Abstract: In order to measure a static field distribution with one scanning operation and to make image distortion corrections with the static field distribution and a gradient field distribution simultaneously considered, an image is reconstructed using a spin echo signal produced under the condition that a time interval between a 90.degree. pulse and a 180.degree. pulse differs from an interval between the 180.degree. pulse and the time origin of the spin echo signal, the static field distribution is evaluated from the relation of distortions to phase errors free from a phase distortion attributed to the characteristic of a detecting part and a phase distortion attributed to the dynamic characteristic of the gradient field, a relations existing between the spatial distortion and phase distortion of the reconstructed image and a magnetic field distribution including the gradient field is obtained, and the distortion magnitude of the reconstructed image is evaluated from the measured magnetic field distribution.

Abstract: An NMR imaging apparatus is disclosed, which comprises imaging means for measuring a cross section of an object to be inspected with a high speed and for reconstructing an image of said cross section, means for specifying a region of interest in the image of the object to be inspected thus reconstructed by said imaging means, and gradient magnetic field control means for controlling a gradient of a magnetic field so that the gradient of the magnetic field at the specified region of interest is substantially greater than that at the other regions, whereby an enlarged image with high image quality at the region of interest is obtained by reconstructing an image of said region of interest after having raised the gradient of the magnetic field at least at said region of interest by means of said gradient magnetic field control means.

Abstract: Two images to be registered are divided into a plurality of image portions. A standard point for the registration is extracted for each of the image portions divided. Coordinate transformations between two images for the registration are conducted for each image portion by using the standard point extracted. The coordinate values transformed between the image portions are smoothed in the case that they discretely change so that they may be smoothly connected.

Abstract: A step of changing the frequency of a rotational field for nuclear magnetic resonance measurement of a medical nuclear magnetic resonance imaging apparatus is set to be smaller in a region of interest in a cross-section of an object to be examined than that in regions of less interest. In the less interesting regions of less interest, the spatial sampling interval is made large and an interpolating calculation is performed for the obtained projection data to provide data at the same spatial interval. The image reconstruction can be performed using an ordinary image reconstruction algorithm.