Granted Patent B2

US 8,964,002 · App. 13/178,537 · Granted Feb 24, 2015

Abstract

Claims (29)

1. A method for registering a first imaging detector to a surface, the method comprising:

projecting a sequence of k images toward the surface, wherein k≧4, and wherein each of the k images comprises a pattern comprising a plurality of lines of light that extend in a direction that is orthogonal to a movement direction, wherein the transition from each one of the k images to the next image in the sequence is achieved by a spatial shift of the pattern by an equal increment along the movement direction so that the left-most image is removed and the next image in the sequence is appended as a right-most image in the pattern, and wherein the pattern encodes an ordered sequence of labels, each label having k binary elements, such that, in the movement direction, any portion of the pattern that is k equal increments long encodes one label of the ordered sequence;

obtaining, for at least a first pixel in the first imaging detector, along at least one line that is parallel to the movement direction, a first sequence of k signal values indicative of the k binary elements of a first label from the ordered sequence of labels; and

correlating, by a processor, the at least the first pixel in the first imaging detector to the surface.

2. The method of claim 1 further comprising:

obtaining, for at least a second pixel in a second imaging detector, along the at least one line that is parallel to the movement direction, the first sequence of k signal values indicative of the k binary elements of the first label from the ordered sequence of labels; and

correlating the at least the second pixel in the second imaging detector to the at least the first pixel in the first imaging detector.

3. The method of claim 1 wherein the pattern is a binary pattern.

4. The method of claim 1 wherein the ordered sequence of labels is part of a de Bruijn cycle.

5. The method of claim 1 wherein projecting the sequence of k images comprises directing lines of light in the blue spectrum.

6. A method for registering first and second imaging detectors to a surface, the method comprising:

projecting a sequence of k images toward the surface, wherein k≧4, and wherein each of the k images comprises a pattern comprising a plurality of lines of light that extend in a direction that is orthogonal to a movement direction, wherein the transition from each one of the k images to the next image in the sequence is achieved by a spatial shift of the pattern by an equal increment along the movement direction so that the left-most image is removed and the next image in the sequence is appended as a right-most image in the pattern, and wherein the pattern encodes an ordered sequence of labels, each label having k binary elements, such that, in the movement direction, any portion of the pattern that is k equal increments long encodes one label of the ordered sequence;

obtaining, for at least a first pixel in the first imaging detector and at least a second pixel in the second imaging detector, along at least one line that is parallel to the movement direction, a first sequence of k signal values indicative of the k binary elements of a first label from the ordered sequence of labels; and

correlating, by a processor, the first and second imaging detectors to each other according to the obtained first sequence of k signal values.

7. The method of claim 6 wherein the pattern is a binary pattern.

8. The method of claim 6 wherein the ordered sequence of labels is part of a de Bruijn cycle.

9. The method of claim 6 wherein directing the sequence of k images comprises projecting lines of light in the blue spectrum.

10. The method of claim 6 wherein projecting the sequence of k images comprises directing lines of light from a laser.

11. The method of claim 6 wherein the increment corresponds to one pixel in each of the imaging detectors.

12. The method of claim 6 further comprising obtaining, for at least an additional pixel along the at least one line that is parallel to the movement direction, a second sequence of k signal values indicative of the k binary elements of a second label from the ordered sequence of labels, wherein the second label is next in sequence from the first label.

13. A method for correlating an imaging detector to a surface being imaged, the imaging detector having at least one pixel, the method comprising:

projecting a sequence of k images toward the surface, wherein k≧4, and wherein each of the k images comprises a pattern comprising a plurality of lines of light that extend in a direction that is orthogonal to a movement direction, wherein the transition from each one of the k images to the next image in the sequence is achieved by a spatial shift of the pattern by an equal increment along the movement direction;

obtaining, for the at least one pixel of the imaging detector, a set of k signal values for each projected k image, along at least one line that is parallel to the movement direction;

using the set of k signal values, assigning a label to the at least one pixel;

using the set of k signal values, assigning a first cost metric to the label of the at least one pixel;

assigning a second cost metric to the label of at least one pixel based on the label ordering sequence; and

adjusting the pixel labels to reduce the first and second cost metrics.

14. The method of claim 13 wherein assigning the second cost metric is based on the label ordering sequence as determined by the deBruijn subcycle.

15. The method of claim 13 wherein the assigning the second cost metric is based on labels of prior and subsequent pixels.

Assignments (12)