Apparatus and method for rapid 3D image parametrization

• US 6,101,269 A
• Filed: 12/19/1997
• Issued: 08/08/2000
• Est. Priority Date: 12/19/1997
• Status: Expired due to Term

• Current Assignee: Auckland UniServices Limited (Auckland University)
• Original Assignee: Lifef/X Networks, Inc.
• Inventors: Charette, Paul G., Hunter, Ian W.
• Primary Examiner(s): Couso, Jose L.
• Assistant Examiner(s): Cage, Shawn B.
• Application Number:
  US08/994,803
• Time in Patent Office: 963 Days
• Field of Search: 250/237 G, 356/376, 359/15, 359/28, 355/22, 382/154
• US Class Current: 382/154
• CPC Class Codes: G01B 11/2545 with one projection direction and several detection directions, e.g. stereo

Abstract

A method and apparatus for rapid three dimensional geometry parametrization of a three dimensional surface. A random speckle pattern is projected upon the surface and imaged to obtain a plurality of two dimensional digital images. The two dimensional images are processed to obtain a three dimensional characterization of the surface. The illuminated surface may be modeled to obtain a parameter set characterizing the surface based upon the two dimensional digital images.

Claims

1. A method for measuring and modeling a three dimensional surface, the method comprising:

a. illuminating the three dimensional surface with a spatially random speckle pattern;

b. imaging the speckle pattern to obtain a plurality of two dimensional digital images; and

c. processing differences due to parallax among the plurality of two dimensional digital images to obtain a three dimensional characterization of the illuminated three dimensional surface.

2. The method as set forth in claim 1, further comprising:

d. modeling the illuminated surface, based upon the plurality of two dimensional digital images, to obtain a parameter set characterizing the illuminated surface.

3. The method as set forth in claim 1, further comprising:

performing steps (a)-(c) more than once to provide an ensemble of speckle patterns and an ensemble of two dimensional digital images, wherein the ensemble of speckle patterns contains at least two distinct speckle patterns.

4. The method as set forth in claim 3, further comprising:

modeling the illuminated surface to obtain a parameter set characterizing the illuminated surface, wherein the modeling is based upon the ensemble of two dimensional digital images.

5. An apparatus for rapid three dimensional image parametrization of a three dimensional surface, the apparatus comprising:

a speckle pattern generator for providing a spatially random speckle pattern upon the three dimensional surface;

a plurality of cameras for imaging the speckle pattern to provide a plurality of two dimensional digital images; and

a processor in communication with the plurality of cameras for processing differences due to parallax among the plurality of two dimensional digital images to obtain a three dimensional digital characterization of the three dimensional surface.

6. The apparatus as set forth in claim 5, wherein the speckle pattern generator comprises a source of optical radiation coupled through an optical fiber.

7. The apparatus as set forth in claim 5, further comprising a speckle pattern shifter for varying the speckle pattern projected upon the three dimensional surface as a function of time.

8. The apparatus as set forth in claim 6, further comprising a speckle pattern shifter for varying the speckle pattern projected upon the three dimensional surface as a function of time.

9. The apparatus as set forth in claim 8, wherein the speckle pattern shifter is a mechanical strain inducer for applying strain to the optical fiber.

10. The apparatus as set forth in claim 9, wherein the mechanical strain inducer is a piezoelectric element.

11. The apparatus as set forth in claim 5, wherein the processor further provides a parameter set characterizing the three dimensional surface.

12. An apparatus for rapid three dimensional image parametrization of a three dimensional surface, the apparatus comprising:

a. a sreckle pattern generator for providing a spatially random speckle pattern upon the three dimensional surface;

b. a plurality of cameras for imaging the speckle pattern to provide a plurality of two dimensional digital images;

c. a memory in communication with the plurality of cameras for storing the plurality of two dimensional digital images; and

d. a processor in communication with the memory for processing differences due to parallax among the plurality of two dimensional digital images to obtain a three dimensional digital, characterization of the three dimensional surface.