Systems and methods for determining a surface profile using a plurality of light sources

1. A method, comprising:

illuminating a subject with light from a plurality of light sources, the plurality of light sources having distinct colors and configured to illuminate the subject from distinct locations, wherein the plurality of light sources includes light sources of at least two distinct colors;

obtaining a multi-color image of the subject, the multi-color image comprising respective values corresponding to respective intensities of light of respective colors for each region of the subject; and

determining a surface profile of the subject in accordance with the respective values corresponding to the respective intensities of light of the respective colors, wherein determining the surface profile of the subject includes:

segmenting a surface of the subject into a plurality of regions; and

determining an orientation of each region of at least a subset of the plurality of regions, wherein determining the orientation of each region includes comparing a first intensity of light of a first color reflected from the region and a second intensity of light of a second color reflected from the region.

2. The method of claim 1 , wherein obtaining the multi-color image includes:

obtaining a parallel-polarization image of the subject;

obtaining a cross-polarization image of the subject; and

subtracting the cross-polarization image of the subject from the parallel-polarization image of the subject to produce the multi-color image of the subject.

3. The method of claim 1 , wherein determining the orientation of each region includes:

determining respective intensities of light, corresponding to respective light sources of the plurality of light sources, reflected from the region; and

comparing the respective intensities of light reflected from the region.

4. The method of claim 1 , including:

determining the surface profile of at least a portion of the subject based on the orientations of the subset of regions.

5. The method of claim 1 , wherein:

the plurality of light sources includes light sources of at least four distinct colors; and

determining the orientation of each region includes:

determining a first angle of the region by comparing a first intensity of light of a first color reflected from the region and a second intensity of light of a second color reflected from the region;

determining a second angle of the region by comparing a third intensity of light of a third color reflected from the region and a fourth intensity of light of a fourth color reflected from the region; and

determining the orientation of the region by combining the first angle and the second angle.

6. The method of claim 1 , further comprising:

combining the surface profile of the subject with a three-dimensional model of the subject.

7. The method of claim 1 , further comprising:

updating a three-dimensional model of the subject in accordance with the surface profile of the subject.

8. The method of claim 1 , wherein the plurality of light sources emits light of respective colors that have distinct spectra.

9. An optical system, comprising:

a plurality of light sources for illuminating a subject, the plurality of light sources having distinct colors and configured to illuminate the subject from distinct locations, wherein the plurality of light sources includes light sources of at least two distinct colors;

an optical image sensor used for obtaining a multi-color image of the subject, the multi-color image comprising respective values corresponding to respective intensities of light of respective colors for each region of the subject;

one or more processors coupled with the optical image sensor; and

memory storing one or more programs for execution by the one or more processors, the one or more programs including instructions for determining a surface profile of the subject in accordance with the respective values corresponding to the respective intensities of light of the respective colors, wherein determining the surface profile of the subject includes:

segmenting a surface of the subject into a plurality of regions; and

determining an orientation of each region of at least a subset of the plurality of regions, wherein determining the orientation of each region includes comparing a first intensity of light of a first color reflected from the region and a second intensity of light of a second color reflected from the region.

10. The optical system of claim 9 , further comprising a rotatably mounted polarizer coupled with the one or more processors, wherein the one or more programs include instructions for:

obtaining a parallel-polarization image of the subject;

obtaining a cross-polarization image of the subject; and

subtracting the cross-polarization image of the subject from the parallel-polarization image of the subject to produce the multi-color image of the subject.

11. The optical system of claim 9 , wherein the instructions for determining the orientation of each region include:

determining respective intensities of light, corresponding to respective light sources of the plurality of light sources, reflected from the region; and

comparing the respective intensities of light reflected from the region.

12. The optical system of claim 9 , wherein:

the plurality of light sources includes light sources of at least four distinct colors; and

the instructions for determining the orientation of each region include instructions for:

determining a first angle of the region by comparing a first intensity of light of a first color reflected from the region and a second intensity of light of a second color reflected from the region;

determining a second angle of the region by comparing a third intensity of light of a third color reflected from the region and a fourth intensity of light of a fourth color reflected from the region; and

determining the orientation of the region by combining the first angle and the second angle.

13. A non-transitory computer readable storage medium storing one or more programs for execution by one or more processors of a computer system, the one or more programs including instructions for:

obtaining a multi-color image of a subject illuminated with a plurality of light sources that has distinct colors and is configured to illuminate the subject from distinct locations, wherein the plurality of light sources includes light sources of at least two distinct colors, the multi-color image comprising respective values corresponding to respective intensities of light of respective colors for each region of the subject; and

determining a surface profile of the subject in accordance with the respective values corresponding to the respective intensities of light of the respective colors, wherein determining the surface profile of the subject includes:

segmenting a surface of the subject into a plurality of regions; and

determining an orientation of each region of at least a subset of the plurality of regions, wherein determining the orientation of each region includes comparing a first intensity of light of a first color reflected from the region and a second intensity of light of a second color reflected from the region.

14. The computer readable storage medium of claim 13 , wherein the one or more programs include instructions for:

obtaining a parallel-polarization image of the subject;

obtaining a cross-polarization image of the subject; and

subtracting the cross-polarization image of the subject from the parallel-polarization image of the subject to produce the multi-color image of the subject.

15. The computer readable storage medium of claim 13 , wherein the instructions for

determining the orientation of each region include:

determining respective intensities of light, corresponding to respective light sources of the plurality of light sources, reflected from the region; and

comparing the respective intensities of light reflected from the region.

16. The computer readable storage medium of claim 13 , wherein:

the plurality of light sources includes light sources of at least four distinct colors; and

the instructions for determining the orientation of each region include instructions for:

determining a first angle of the region by comparing a first intensity of light of a first color reflected from the region and a second intensity of light of a second color reflected from the region;

determining a second angle of the region by comparing a third intensity of light of a third color reflected from the region and a fourth intensity of light of a fourth color reflected from the region; and

determining the orientation of the region by combining the first angle and the second angle.