Abstract: An image generated by the detected signals of a scanning electron microscope is divided, for example, into a plurality of rectangular small areas with the boundaries parallel to the y-axis. The relative height in the boundary is obtained by conducting one dimensional integration for respectively boundaries. Thereafter, the relative height difference between the boundaries is determined by conducting one dimensional integration for each area in the direction perpendicular to the boundary. Thereby, the surface three dimensional topography having less distortion can be measured, even in case errors are included in the normal distribution which indicates the surface topography of the specimen, by adjusting and determining the height in the area by the interporating operation.

Abstract: Disclosed is a method and apparatus for measurement of surface topography of a sample by using a scanning electron microscope, in which: secondary electrons released from the sample are detected by detectors which are four or an integral multiple of four in number and which are disposed above the sample to surround the sample; differential coefficients in two directions perpendicularly intersecting each other at the scanning point are obtained from the detected signals; the differential coefficients are successively summing-integrated along the two directions thereby obtaining surface topography of the sample; and at the same time the calculation expression for calculating the surface topography is corrected with the sample table inclined.

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: A scanning electron microscope for scanning the surface of a specimen with an electron beam to detect secondary electrons, backscattered electrons, or X-rays emitted from the specimen, thereby forming an image of the surface of the specimen, is provided with a specimen table capable of making a horizontal movement, a vertical movement a rotating operation and a tilting operation, an arithmetic unit for converting the output of a detector for detecting the secondary electrons, backscattered electrons or X-ray into a digital signal to store the digital signal, and for calculating the amount of each of the horizontal movement, vertical movement, rotating operation and tilting operation of the specimen table, on the basis of the stored information, an indication given from the outside, and others, and a controller for controlling the specimen table on the basis of a calculated value from the arithmetic unit.

Abstract: Distortion models consisting of two forward and backward reciprocating planes that let a corrected image correspond to an uncorrected image for each scanning direction are constituted to let an uncorrected satellite image scanned by a reciprocating scanning sensor with scanning overlap or scanning underlap correspond to a corrected image after distortion correction, by means of a continuous mapping function on a 1:1 basis. It is determined whether each point on the corrected image is a point on an overlapping scan or on an underlapping scan or on a normal scan from the existence of a real point on the distortion models.

Abstract: By using a low-frequency component of attitude data of an uncorrected image resulting from scanning the ground by means of a sensor mounted on a satellite, low-frequency distortion correction coefficients are calculated. By using a high-frequency component of attitude data, a change rate is calculated. From said low-frequency distortion correction coefficients and said change rate, distortion correction coefficients covering a high frequency are calculated. By applying bidirectional resampling to the uncorrected image by using said distortion correction coefficients covering a high frequency, a corrected image is obtained.

Abstract: Novel thioketene derivatives of the formula: ##STR1## wherein R.sup.1 is hydrogen atom, an alkyl group, a lower alkenyl group, a phenyl group or a group of the formula: --B--Y;Y is a nitrogen-containing monocyclic heterocyclic group or a substituted or unsubstituted phenyl group;B is a straight or branched lower alkylene group;R.sup.2 and R.sup.3 are both a lower alkyl group or are combined together to form a group of the formula: --CH.sub.2 CH.sub.2 -- or --CH.dbd.CH--;R.sup.4 is hydrogen atom, a lower alkyl group or a (lower alkoxy)carbonyl group;A is a group of the formula: --(CH.sub.2).sub.n -- or --CH(COOR.sup.5)--;n is an integer of 0, 1 or 2 andR.sup.5 is a lower alkyl group,are disclosed. The compound (I) is useful as an agent for treating and protecting various liver diseases.

Abstract: Azimuth compression processing is carried out by the steps of determining Doppler rate time change data a reconstructed scene from orbit data of a sattelite or aircraft, determining azimuth coordinates transformation data of an image after range compression, that is, resampling position designation data, from the Doppler rate time change data, resampling the image after range compression, in the azimuth direction using the azimuth coordinates transformation data, keeping unaltered the Doppler rate of a point image relating to the image after coordinates transformation irrespective to the position in the azimuth direction inside the scene, and thereafter using FFT.