FIELD: optic-electronic tool-making, possible use in scanning devices of modern automated ballistic identification complexes for recording images of micro-relief of side surfaces of fired bullets and bottom of fired shells and inputting these images into system.
SUBSTANCE: method for scanning images of micro-relief of side surfaces of fired bullets and shells includes scanning by means of video camera with charge-coupled matrix of individual rectangular fragments of side surface of object, further processing of received information and following synthesis of full scan, where focusing of objective of video camera with charge-coupled matrix on surface object element selected for scanning is performed by progressive motion of the camera along optical axis of objective, and on side surface of the object two light strokes are formed simultaneously, which are shown of charge-coupled matrix as two lengths of curved shape, positioned on different sides of best focusing line, where top points of aforementioned lengths are at A and B distances from aforementioned line, then value X is determined from values of A and B using a derived formula, β is computed - angle of inclination of deformed element of scanned surface, after that defocusing value is determined and position of focusing carriage is corrected once until coincidence of top points of aforementioned lengths is reached, further, focusing process is repeated for other positions of side surface of object. Device for scanning images of micro-relief of side surfaces of fired bullets and shells of automated ballistic identification complex contains illuminants, object holder, mechanisms of longitudinal scanning, object rotation and focusing unit, focusing system, video camera with charge-coupled matrix, analog-digital converter and computer. Device is provided with an additional slit illuminant, which is positioned oppositely to main slit illuminant relatively to optical axis of video camera objective, where video camera with charge-coupled matrix and illuminant, main and additional slit illuminants mounted on it, is installed with possible longitudinal movement along optical axis of video camera objective.
EFFECT: increased precision and reduced time of automatic focusing of optical system on surface element of cylindrical or flat object (fired bullets and shells) selected for scanning.
2 cl, 6 dwg, 1 tbl
