System for measuring objects in three dimensions
OwnerDale G. O'Harrainventor
Life of this patent
Estimating the term…
Abstract
A three-dimensional measuring system particularly for dental and other space-limited uses has a laser diode projecting a triangulating beam at a surface to be mapped, with the beam scanned repeatedly across the surface. Photodetectors detect the position of the beam as reflected from the mapped surface, giving by triangulation Z-axis or depth information. Correlation of a particular point with the position of the scanner along the scan line gives Y-axis information, or information in a width direction. The scanner and diode are mounted on a slide or platform device which moves perpendicularly to the Y axis in the direction in and out of the mouth, driven by a stepper motor, and the monitored position of the stepper motor is coordinated with the other information on each spot to yield X-axis information.
Claims21
A system for three dimensional mapping of the topography of a small object, and for generating digitized signals indicative of the topography, for use in viewing the topography in a three dimensional representation on a screen and/or for generating a model of the topography, comprising,
- a probe housing for placement adjacent to the small object or objects to be surveyed,
- slidable sled means mounted in the housing so as to slide in and out longitudinally on the housing in an X-axis direction,
- first motor means for advancing the sled means along the X-axis direction,
- first position means associated with the motor means and the sled means, for recording the position of the sled means, to produce X-axis readings at surveyed points,
- beam scanning means on the sled means, for repeatedly scanning a focused beam of light across the surfaces of the small objects, by swinging the beam from a rotational point of origin,
- second motor means associated with the beam scanning means, for causing the beam to be scanned,
- second position means associated with the second motor means, for encoding the position of the beam scan and generating a signal in accordance therewith, for each point surveyed, representing Y-axis positional information, perpendicular to the X axis, and
- triangulation light sensor means on the sled means, mounted off-axis with respect to the light beam, for detecting the depth of a surveyed point away from the sled means, and third position means for encoding the depth and for generating a signal in accordance therewith, representing Z-axis or depth information,
- whereby a series of points on the small object are surveyed, with each point assigned X-axis, Y-axis and Z-axis information, so that the topography of the small object can be reproduced with the aid of a computer.
A method for mapping in three dimensions the topography of a dental patient's tooth, comprising,
- providing a probe of narrow dimensions having a housing capable of being inserted comfortably into the patient's mouth,
- advancing a platform or sled within the housing longitudinally with respect to the housing along an X axis, while recording the position of the sled representative of X-axis position of points surveyed,
- while the platform is advancing along the X axis, scanning a laser beam to sweep across a tooth, and encoding the position of the beam in its sweep and generating a second signal representative of a Y-axis position of the beam and thus of each point being surveyed,
- while the beam is being scanned across the tooth, sensing the position at which the beam impinges on the tooth with an off-axis photodetector means spaced away from and off the axis of the beam on the platform, so as to determine the height of each surveyed point from the platform by triangulation via the laser beam and the detector position, and encoding the detected position and generating a signal in accordance therewith, for Z-axis information,
- receiving all of the signals for X-axis, Y-axis and Z-axis information in a computer and generating with the computer from said signals an image of the topography of the tooth in three dimensions, usable for displaying an image for review and editing of or for generating a model of the tooth's topography with a model producing apparatus.
A three dimensional scanner device for obtaining and recording three dimensional information concerning the topography of an object, comprising,
- triangulation means for determining one dimension of the object, a height dimension, said triangulation means including a light beam source producing a beam, and detection means for receiving light from surfaces of the object off-axis from the beam to determine height by triangulation,
- width scanner means for scanning the beam through a scan path in a width direction,
- width position determining means for recording a width position for each point recorded by the triangulation means, based on the position of the scanner means at each subject point, and
- depth scanner means for moving the width scanner means and the triangulation means along a depth axis, and
- depth position determining means for determining and recording a depth position along the depth axis, for each point recorded by the triangulation means, based on position of the scanner means along said depth axis.
Dependencies are inferred from the claim text.