Methods and systems for generating color images

Patent metadata

Field	Value
Publication number	US-9956061-B2
Application number	US-201615175311-A
Country	US
Kind code	B2
Filing date	Jun 7, 2016
Priority date	Aug 1, 2013
Publication date	May 1, 2018
Grant date	May 1, 2018

Abstract

Systems for generating in-focus color images are provided. Related methods and devices are also provided.

First claim

What is claimed is:

1. A system for generating focused color image data, the system comprising:
a light source that produces light comprising a plurality of wavelengths;
an optics system optically coupled to the light source and operable to focus each of the plurality of wavelengths to a corresponding plurality of respective focal lengths;
a detector configured to collect image data for each of the plurality of wavelengths at each corresponding plurality of respective focal lengths; and
a processor configured to, for an image location in the image data:
determine, for each of the plurality of wavelengths, a focal length of the corresponding plurality of respective focal lengths for which the respective wavelength is focused relative to the object at the image location; and
combine the image data for each of the plurality of wavelengths at the determined respective focal lengths, thereby generating focused color image data for the image location.

2. The system of claim 1 , wherein the optics system comprises a movable optical component configured to, for each of the plurality of wavelengths, scan through the corresponding plurality of respective focal lengths.

3. The system of claim 1 , wherein the plurality of wavelengths comprises at least three wavelengths.

4. The system of claim 3 , wherein the image data for at least one wavelength of the plurality of wavelengths comprises intensity data for the at least one wavelength for each of the plurality of the respective focal lengths of the at least one wavelength.

5. The system of claim 4 , wherein the plurality of wavelengths comprise a red light wavelength, a green light wavelength; and a blue light wavelength.

6. The system of claim 4 , wherein the image data includes position data corresponding to a plurality of pixels in the detector.

7. The system of claim 1 , wherein:
the light source comprises a white light source; and
the detector comprises a color image detector.

8. The system of claim 1 , wherein the processor is configured to generate focused color image data for a plurality of image locations, and wherein at least one of the plurality of wavelengths has different determined respective focal lengths for at least two of the plurality of image locations.

9. The system of claim 1 , further comprising a scanning system configured to collect surface topology data of the object.

10. The system of claim 9 , wherein:
the scanning system comprises a monochromatic light source used to illuminate the object with monochromatic light;
a focal length of the monochromatic light is scanned through a plurality of different monochromatic light focal lengths;
for each of a plurality of different locations in the focused color image, one of the monochromatic light focal lengths is selected, for which the monochromatic light is focused relative to the object at the respective location, based on analysis of the monochromatic light reflected from the object at the respective location; and
the surface topology data is generated based on the selected monochromatic light focal lengths.

11. The system of claim 10 , wherein the surface topology data and the focused color image of the object are aligned in a common frame reference.

12. The system of claim 1 , wherein the system is wholly or partially incorporated into a hand-held device.

13. The system of claim 1 , wherein the light source produces light that simultaneously comprises each of the plurality of wavelengths.

14. The system of claim 1 , wherein the determined focal length for a wavelength of the plurality of wavelengths being focused relative to the object results in a blur circle diameter not greater than 0.4 mm.

15. The system of claim 14 , wherein the determined focal length for a wavelength of the plurality of wavelengths being focused relative to the object results in a blur circle diameter not greater than 0.2 mm.

16. The system of claim 1 , wherein the determination of each of the plurality of respective wavelength focal lengths is based on:
intensity of light reflected from the object,
spatial frequency contents of an image portion of at least one of the plurality of wavelengths reflected from the object, or
a combination thereof.

17. A computer-implemented method for generating focused color image data of an object, the method comprising:
processing image signals corresponding to a plurality of different focal lengths for each of a plurality of wavelengths of light that is reflected from the object so as to generate image data for each of the plurality of wavelengths;
for a location in the image data:
determining, for each of the plurality of wavelengths, a focal length of the corresponding plurality of respective focal lengths for which the respective wavelength is focused relative to the object at the image location; and
combining the image data for each of the plurality of wavelengths at the determined respective focal lengths, thereby generating focused color image data for the image location.

18. The method of claim 17 , wherein the plurality of wavelengths comprises at least three wavelengths.

19. The method of claim 18 , wherein the at least three wavelengths comprise a wavelength between about 465 nm and about 485 nm, a wavelength between about 500 nm and about 520 nm, and a wavelength between about 640 nm and about 660 nm.

20. The method of claim 18 , wherein the image data for at least one wavelength of the plurality of wavelengths comprises intensity data for the at least one wavelength for each of the plurality of the respective focal lengths of the at least one wavelength.

21. The method of claim 17 , wherein the image signals are generated in response to reflections from the object produced via white light illumination of the object.

22. The method of claim 17 , further comprising processing image signals to generate surface topology data of the object.

23. The method of claim 22 , wherein the imaging signals processed to generate the surface topology data are generated in response to reflections from the object of monochromatic light that is scanned through a plurality of different focal lengths, the method further comprising:
for each of a plurality of different locations in the focused color image, selecting one of the monochromatic light focal lengths, for which the monochromatic light is focused relative to the object at the respective location, based on analysis of the monochromatic light reflected from the object at the respective location; and
generating the surface topology data based on the selected monochromatic light focal lengths.

24. The method of claim 23 , wherein the surface topology data and the focused color image of the object are aligned in a common frame of reference.

25. The method of claim 17 , wherein the determined focal length for a wavelength of the plurality of wavelengths being focused relative to the object results in a blur circle diameter not greater than 0.4 mm.

26. The method of claim 25 , wherein the determined focal length for a wavelength of the plurality of wavelengths being focused relative to the object results in a blur circle diameter not greater than 0.2 mm.

27. The method of claim 17 , wherein the selection of the first and second wavelength focal lengths is based on at least one of: (a) intensity of light reflected from the object, and (b) spatial frequency contents of an image portion of at

Assignees

• Align Technology Inc

Inventors

• Moalem Yosi

Classifications

• H04N25/134 Primary

  based on three different wavelength filter elements · CPC title

• H04N23/56

  provided with illuminating means · CPC title

• H04N23/673

  based on contrast or high frequency components of image signals, e.g. hill climbing method · CPC title

• A61B5/0068 Primary

  Confocal scanning · CPC title

• G01B11/24

  for measuring contours or curvatures · CPC title