Three-dimensional modeling of the oral cavity

• US 7,724,932 B2
• Filed: 10/31/2007
• Issued: 05/25/2010
• Est. Priority Date: 01/27/2004
• Status: Active Grant

• Current Assignee: Densys Ltd.
• Original Assignee: Densys Ltd.
• Inventors: Cohen, Carmi, Neta, Uri, Ernst, Maurice Moshe, Geffen, Micha
• Primary Examiner(s): Johns; Andrew W
• Application Number:
  US11/980,241
• Publication Number:
  US 20080273773A1
• Time in Patent Office: 937 Days
• Field of Search: 382/128, 382/154, 382/286, 348/66, 348/77, 348/136, 356/603, 356/610
• US Class Current: 382/128
• CPC Class Codes: G01B 11/25 by projecting a pattern, e.g. one or more lines, moiré fringes on the object G01B11/255 takes precedence ; image analysis for depth or shape recovery G06T7/50

Abstract

A method for creating three-dimensional models of intra-oral scenes and features. The intra-oral scene is illuminated by a two-dimensional array of structured illumination points, with anti-aliasing achieved by using stored two-dimensional patterns of pixels for anti-aliasing. Using a single camera to form images reduces the amount of apparatus necessary to introduce into the patient'"'"'s mouth. Three-dimensional models are obtained from the single image by triangulation with a stored image of the structured illumination onto a reference surface such as a plane. Alternative methods include the use of “bar-coded” one-dimensional patterns.

Claims

1. A method for three-dimensional modeling of the surface features of a intra-oral scene for a dental application, the method comprising:

generating a two-dimensional array of a plurality of random two-dimensional patterns;

projecting said array onto a reference surface from a first angle;

acquiring a first image of said array projected on said reference surface, wherein said acquiring said first image is performed from a second angle;

projecting said array onto the intra-oral scene said first angle;

acquiring a plurality of second images of said array projected on the intra-oral scene from a plurality of second angles;

calculating the two-dimensional relative positions of said random patterns based on the relative positions thereof in an image;

matching said random two-dimensional patterns in said first image with said random two-dimensional patterns in at least one of said plurality of second images;

calculating the parallax between said random patterns in said first image with said random patterns in said at least one of said plurality of second images;

calculating a three-dimensional relative positions of said random patterns based on said two-dimensional relative positions and said parallax; and

constructing a three-dimensional model of the intra-oral scene based on said three-dimensional relative positions.

2. The method of claim 1, wherein said reference surface is selected from a group consisting of:

a plane; and

a general surface having a mathematical description.

3. The method of claim 1, wherein said random two-dimensional patterns are patterns of aggregated pixels.

4. The method of claim 1, wherein said matching is done by hierarchical correlation.

5. A method for three-dimensional modeling of the surface features of a intra-oral scene for a dental application, the method comprising:

generating a random one-dimensional pattern;

projecting said pattern as a series of scanned lines onto a reference surface from a first angle;

acquiring a first image of said scanned lines on said reference surface, wherein said acquiring said first image is performed from a second angle;

projecting said pattern as a series of scanned lines onto the intra-oral scene from said first angle;

acquiring a second image of said series of scanned lines on the intra-oral scene from said second angle;

calculating the two-dimensional relative positions of said scanned lines based on the relative positions thereof in an image;

matching said random one-dimensional pattern in said first image with said random one-dimensional pattern in said second image;

calculating the parallax between said random pattern in said first image with said random pattern in said second image;

calculating a three-dimensional relative positions of said random patterns based on said two-dimensional relative positions and said parallax; and

constructing a three-dimensional model of the intra-oral scene based on said three-dimensional relative positions.

6. The method of claim 5, wherein said matching is done by hierarchical correlation.

7. The method of claim 5, wherein said reference surface is selected from a group consisting of:

a plane; and

a general surface having a mathematical description.

8. The method of claim 5, wherein said random one-dimensional pattern is a pattern of aggregated pixels.