Co-planar electromagnetic profile scanner

A co-planar profile scanner, comprising:

• (a) an illuminator for illuminating a portion of the surface of an object along the line of intersection of a plane with the object by projecting in the plane onto the surface of the object a spatially varied pattern of electromagnetic radiation selected so that any portion of the pattern of at least some preselected minimum size is distinguishable from any other portion of the pattern, said pattern comprised of an array of spatially arranged pattern elements of at least two mutually distinguishable types, where each pattern element comprises at least a first and a second discrete physical characteristic, each discrete physical characteristic being associated with a discrete type of information;
• (b) means for forming an image of the illuminated portion of the object from the electromagnetic radiation reflected in the plane from the object;
• (c) means for correlating the projected pattern with the image, so as to establish a match of each identifiable portion of the reflected radiation with a corresponding portion of the projected pattern, whereby the portion of the surface of the object from which the reflected radiation from the corresponding portion of the projected pattern has been reflected is ascertained;
• and
• (d) a coordinate calculator for computing the spatial coordinates of the portion of that surface of the object on which each distinguishable portion of the projected pattern falls.

A co-planar profile scanner, comprising:

• a frame surrounding a planar scan zone through which an object whose profile is to be measured may pass;
• and
• at least three scanning heads mounted to the frame and approximately uniformly angularly spaced about the center of the scan zone,
• each discrete scanning head having
• an illuminator for illuminating a portion of the surface of the object along the line of intersection of the plane which includes the scan zone with the object by projecting in the plane toward the scan zone and onto the surface of the object a spatially varied pattern of electromagnetic radiation selected so that any portion of the pattern of at least some preselected minimum size is distinguishable from any other portion of the pattern, said pattern comprised of an array of spatially arranged pattern elements of at least two mutually distinguishable types, where each pattern element comprises at least a first and a second discrete physical characteristic, each discrete physical characteristic being associated with a discrete type of information, and
• a detector for receiving electromagnetic radiation reflected in the plane which includes the scan zone from the illuminated portion of the object, and
• each discrete scanning head further being associated with and connected to
• a converter for converting the received electromagnetic radiation into reflection data,
• a discriminator for processing said reflection data for correlating each distinguishable portion of the projected pattern with the image of its reflection by comparing transmission data representing the pattern of the illuminating beam with the reflection data, so as to establish a match of an identifiable portion of the reflected radiation and a corresponding portion of the illuminating beam, whereby the portion of the surface of the object from which the reflected radiation has been reflected is ascertained, and
• a coordinate calculator for computing the spatial coordinates of the portion of that surface of the object on which each distinguishable portion of the pattern falls.

A co-planar profile scanner for measuring an object by measuring the spatial coordinates of the line of intersection of a plane with the surface of the object, comprising

• (a) an illuminator for illuminating a portion of the surface of the object along the line of intersection of the plane with the object by projecting in the plane onto the surface of the object a coded spatially varied pattern of electromagnetic radiation selected so that any portion of the pattern of at least some preselected minimum size is distinguishable from any other portion of the pattern, said pattern comprised of an array of spatially arranged pattern elements of at least two mutually distinguishable types, where each pattern element comprises at least a first and a second discrete physical characteristic, each discrete physical characteristic being associated with a discrete type of information;
• (b) a detector for receiving electromagnetic radiation reflected in the plane from the illuminated portion of the object;
• (c) a converter for converting the received electromagnetic radiation into computer-readable digital reflection data;
• (d) a discriminator for processing said data for correlating each distinguishable portion of the projected pattern with its reflection by comparing transmission data representing the pattern of the illuminating beam with the reflection data, so as to establish a match of an identifiable portion of the reflected radiation and a corresponding portion of the illuminating beam, whereby the portion of the surface of the object from which the reflected radiation has been reflected is ascertained;
• and
• (e) a coordinate calculator for computing the spatial coordinates of the portion of that surface of the object on which each distinguishable portion of the pattern falls.

A method for measuring an object by measuring the spatial coordinates of the line of intersection of a plane with the surface of the object, comprising the steps of:

• (a) illuminating the surface of the object along the line of intersection of the plane with the object by projecting in the plane onto the surface a spatially varied pattern of electromagnetic radiation selected so that any portion of the pattern of at least some preselected minimum size is distinguishable from any other portion of the pattern, said pattern comprised of an array of spatially arranged pattern elements of at least two mutually distinguishable types, where each pattern element comprises at least a first and a second discrete physical characteristic, each discrete physical characteristic being associated with a discrete type of information;
• (b) detecting electromagnetic radiation reflected in the plane from the illuminated portion of the object;
• (c) converting the received electromagnetic radiation into computer-readable digital reflection data;
• (d) correlating each distinguishable portion of the projected pattern with the image of its reflection by comparing transmission data representing the pattern of the illuminating beam with the reflection data, so as to establish a match of an identifiable portion of the reflected radiation and a corresponding portion of the illuminating beam, whereby the portion of the surface of the object from which the reflected radiation has been reflected is ascertained;
• and
• (e) computing the spatial coordinates of the portion of that surface of the object on which each distinguishable portion of the pattern falls.