US 4,185,918 AGranted

Arrangement for sensing the characteristics of a surface and determining the position of points thereon

AssigneeSolid Photography Inc.

InventorsPaul L. DiMatteo, Joseph A. Ross, Howard K. Stern

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Abstract

The surface to be sensed or scanned is placed in the path of a projector which is moved along an axis of the surface. The path of motion of the projector is subdivided into predetermined sections which are illuminated by the projector in accordance with a predetermined sequential pattern. This procedure of moving the projector is repeated a predetermined number of times, with a separate illuminating pattern prevailing each time that the projector is moved relative to the surface and traverses the entire surface to be scanned. The combinations of the patterns obtained from the repeated scannings of the projector define closely-spaced sections of the surface. The patterns are coded so that each section is uniquely defined in coded form. A camera having the entire surface within its field of view photographs the surface each time that the projector is moved along the axis of the surface.

Claims51

Dependent claims

A method for sensing and locating points on a surface comprising the steps of:

generating a projection field directed onto a surface;
applying relative motion between said projection field and said surface in at least one direction parallel to a coordinate axis applied to the surface;
subdividing said projection field into a number of selected sections during said relative motion and irradiating said surface with different variations of said subdivided projection field so that each section is illuminated at least once;
recording within a field of view images of said surface as irradiated by the subdivided projection field, recording a calibrated reference surface and reading said recorded images in relation to said reference surface to define the location of a predetermined point on said surface first-mentioned and appearing within said field of view;
projecting in sequence by said projection field preselected patterns onto the surface for subdividing the projection field into predetermined sections, said projected patterns on said surface having irradiated sections and non-irradiated sections, each pattern of irradiated sections and non-irradiated sections corresponding to an assigned code;
said reading step comprising further reading each projected pattern of irradiated and non-irradiated sections and reading the sections in which a preselected point appears;
combining said patterns for obtaining a predetermined total number of sections, said projection field being subdivided into said total number of sections, the number of said patterns and the total number of sections being related by said assigned code;
and relating the patterns and sections in which the point appears to identify the position in three-dimensional space of the point on said surface;
said relative motion including the step of traversing said surface with said projection field for each of said patterns, said projection field and said surface being moved relative to each other progressively to form a pattern during a traversal of said surface.

6 more elements

An arrangement for sensing and locating points on a surface comprising:

means for generating a projection field directed onto a surface;
means for applying relative motion between said projection field and said surface in at least one direction parallel to a coordinate axis applied to the surface;
means for subdividing said projection field into a number of selected sections during said relative motion and irradiating said surface with different variations of said subdivided projection field so that each section is illuminated at least once;
means for recording within a field of view images of said surface as irradiated by the subdivided projection field;
means for recording a calibrated reference surface and reading said recorded images in relation to said reference surface to define the location of a predetermined point on said first-mentioned surface and appearing within said field of view;
said projection field projecting in sequence preselected patterns onto the surface for subdividing the projection field into predetermined sections, said projected patterns on said surface having irradiated sections and non-irradiated sections, each pattern of irradiated sections and non-irradiated sections corresponding to an assigned code;
said reading means reading further each projected pattern of irradiated and non-irradiated sections and reading the sections in which a preselected point appears;
said patterns being combined for obtaining a predetermined total number of sections, said projection field being subdivided into said total number of sections, the number of said patterns and the total number of sections being related by said assigned code;
patterns and sections in which the point appears being related to identify the position in three-dimensional space of the point on said surface, said surface being traversed with said projection field for each of said patterns during said relative motion, said projection field and said surface being moved relative to each other progressively to form a pattern during a traversal of said surface.

6 more elements

Dependencies are inferred from the claim text.