Patent ID: 6573855
Filing Date: 2003-06-03
Classification: G01S

Abstract:
In a three-dimensional exploring method for finding the location of an object present within a medium by sequentially effecting a transmitting/receiving step of transmitting a wave signal by means of an electromagnetic wave or sonic wave into the medium and receiving the signal reflected from the object within the medium in the course of movement over the surface of the medium and a three-dimensional voxel data generating step of generating three-dimensional voxel data in the form of coordinates (x, y, t) consisting of a position (x, y) on the medium surface and a reflection time (t) based on the intensity of the reflected signal;the method comprising: a maximum-magnitude extracting-step of extracting, from the three-dimensional voxel data generated by the three-dimensional voxel data generating step, a maximum value of the magnitude of the amplitude value and a reflection time tMAX providing the maximum value in the direction of the reflection time (t) axis for the position (x, y) on the medium surface; a plane-locating step of locating, respectively on an x-y plane of a predetermined reflection time (t), said maximum value and said reflection time tMAX extracted by the maximum-magnitude extracting step; an object-voxel selecting step at which said x-y plane having said maximum value located thereon is displayed and a coordinate point is designated on said displayed plane in accordance with a manual input operation, so that one or more object voxels are selected by specifying them with said designated coordinate point and said reflection time tMAX associated therewith; a binarizing step of extracting a candidate voxel group consisting of a plurality of voxels having amplitude values of positive or negative polarity and having magnitudes greater than a predetermined threshold and interconnected with each other; and a connecting/composing step of extracting, from the candidate voxel group extracted by the binarizing step, a connection-candidate voxel group to be connected to the object voxels selected by the object voxel selecting step and connecting said connection-candidate voxel group with said object voxels thereby to compose an object voxel group.