Three dimensional color imaging

• US 5,708,498 A
• Filed: 03/04/1996
• Issued: 01/13/1998
• Est. Priority Date: 03/04/1996
• Status: Expired due to Term

• Current Assignee: National Research Council Canada
• Original Assignee: National Research Council Canada
• Inventors: Fournier, Paul, King, Lawrence, Rioux, Marc
• Primary Examiner(s): Hantis, K.
• Application Number:
  US08/608,006
• Time in Patent Office: 680 Days
• Field of Search: 356/375, 356/376, 356/73, 356/402, 356/407, 356/425, 356/300, 356/326, 356/328
• US Class Current: 356/73
• CPC Class Codes: G01B 11/24 for measuring contours or curvatures

Abstract

An optical method and apparatus is provided for determining the color and profile of a target surface of an object. The target surface is scanned with an incident beam of light containing a plurality of wavelengths including at least one well defined wavelength. A return beam reflected from the target is split into at a first and second return beam. The first return beam is utilized for detecting the profile of the target surface; and, a plurality of detectors are provided that detect color information corresponding to the target surface from the second return beam.

Claims

1. An optical method of determining the color and profile of a target surface comprising the steps of:

(a) scanning the target surface with an incident beam of light containing a plurality of wavelengths including at least one well defined wavelength;

(b) splitting a return beam that has reflected from the target surface into a plurality of separate return beams including at least a first and second return beam;

(c) utilizing the first return beam that has reflected from the target surface for detecting the profile of the target surface;

(d) utilizing the second return beam to detect color information corresponding to the target surface;

(e) providing the second return beam to a means for detecting one or more of red, green, and blue spectral contents; and

(f) generating signals representative of the respectively colored spectral content of the second return beam from the target surface.

2. A method of determining the color and profile of a target surface as defined in claim 1, further comprising the steps of:

(i) tapping a portion of the beam of light before the step of scanning the target surface;

(ii) providing the tapped portion of the beam to a means for detecting the spectral content of the tapped portion of the beam and generating signals representative of the spectral content of the tapped portion of the beam;

(iii) generating said signals representative of the red, green, and blue content of the tapped portion of the beam and,

(iv) determining as a function of the signals representative of the spectral content of the tapped portion of the beam and the signals representative of the color of the target surface, normalized values representative of the color of the target surface.

3. An optical method of determining the color and profile of a target surface as defined in claim 2, wherein the tapped beam and the beam of light incident upon the target surface contain substantially the same proportions of red, green and blue spectral contents.

4. An optical method of determining the color and profile information as defined in claim 2, wherein the step of providing the tapped portion of the beam to a means for detecting the spectral content of the tapped portion of the beam further comprises the step of detecting the red, green and blue contents of the tapped portion of the beam for generating signals representative of the red, green, and blue spectral contents of the tapped portion of the beam.

5. An optical apparatus for determining the color and profile of a target surface comprising:

(a) means for scanning the target surface with an incident beam of light containing a plurality of wavelengths including at least one well defined wavelength;

(b) means for splitting the return beam that has reflected from the target surface into a plurality of separate return beams, including at least a first return beam and a second return beam;

(c) means for detecting the profile of the target surface in response to the first return beam that has reflected from the target surface; and

(d) means for detecting color information corresponding to the target surface in response to the second return beam, further comprising

a means for dispersing the second return beam into a plurality of separate beams according to their wavelengths and

a plurality of detectors spaced apart and positioned to receive the plurality of separate beams.

6. An optical apparatus for determining the color and profile of a target surface as defined in claim 5, including means for reducing noise present at an input of the apparatus.

7. An optical apparatus for determining the color and profile of a target surface as defined in claim 6, further comprising:

(i) means for tapping a portion of the incident beam of light before scanning the target surface, said means being capable of providing a tapped beam of light;

(ii) means for detecting the spectral content of the tapped beam and generating signals representative of the respective spectral content of the tapped portion of the beam; and

,

(iii) means for determining as a function of the signals representative of the spectral content of the tapped portion of the beam and signals representative of the color of the target surface, normalized values representative of the color of the target surface.

8. An optical apparatus for determining the color and profile of a target surface defined in claim 7, wherein the means for determining the spectral content detects the red, green and blue spectral content of the tapped beam and generates signals representative of the red, green, and blue spectral content of the tapped portion of the beam.

9. An optical apparatus for determining the color and profile of a target surface as defined in claim 8, including means for dispersing the tapped beam into a plurality of separate tapped beams according to their wavelengths and a plurality of detectors spaced apart and positioned to receive the plurality of separate tapped beams.

10. An optical apparatus for determining the color and profile of a target surface as defined in claim 8, wherein the means for detecting the red, green and blue content of the tapped beam and generating signals representative of the red, green and blue content of the tapped portion of the beam further comprises

a means for dispersing the tapped beam into a plurality of separate tapped beams according to their wavelengths and

a plurality of detectors spaced apart and positioned to receive the plurality of separate tapped beams.