Multi-View Difraction Grating Imaging With Two-Dimensional Displacement Measurement For Three-Dimensional Deformation Or Profile Output

• US 20130147919A1
• Filed: 12/07/2012
• Published: 06/13/2013
• Est. Priority Date: 12/09/2011
• Status: Abandoned Application

• Current Assignee: California Institute of Technology
• Original Assignee: California Institute of Technology
• Inventors: Xia, Shuman, Gdoutou, Alexandra
• Application Number:
  US13/708,679
• Publication Number:
  US 20130147919A1
• Time in Patent Office: Days
• US Class Current: 348/46
• CPC Class Codes: G01B 11/00 Measuring arrangements characterised by the use of optical techniques
• CPC Class Codes: G01B 11/002 for measuring two or more coordinates
• CPC Class Codes: G01B 11/162 by speckle- or shearing interferometry
• CPC Class Codes: G01B 11/24 for measuring contours or curvatures
• CPC Class Codes: H04N 13/204 using stereoscopic image cameras stereoscopic photography G03B35/00

Abstract

Hardware and software methodology is described for three-dimensional imaging in connection with optical transmission grating used to achieve a plurality of views of an area or entirety of an object imaged with a single digital camera for recording and subsequent processing. Such processing produces three-dimensional data (in terms of element displacement and/or object profile) using a two-dimensional displacement measurement technique only.

Claims

1. A method of three-dimensional imaging, comprising:

directing at least one camera at a diffraction grating positioned between the at least one camera and a target;

capturing light, with the at least one camera, of a patterned surface of the target in a plurality of images from different angles; and

analyzing images, with at least one processor, by a two-dimensional displacement measurement technique to determine three-dimensional data for the target.

2. The method of claim 1, wherein the plurality of images are captured without distortion.

3. The method of claim 1, further comprising passing light through the target for camera capture.

4. The method of claim 1, further comprising reflecting light from the target for camera capture.

5. The method of claim 1, wherein two images are analyzed.

6. The method of claim 5, wherein zero and first order images are compared.

7. The method of claim 6, wherein the first order images are selected from positive and negative first order images.

8. The method of claim 5, wherein the grating is blazing grating and the first order image is a positive first order image.

9. The method of claim 1, wherein three images are analyzed.

10. The method of claim 9, wherein the grating is beam splitter grating.

11. The method of claim 10, wherein negative first, zero and positive first order images are analyzed.

12. The method of claim 1, wherein the system includes only one camera.

13. The method of claim 1, wherein capturing light with the at least one camera further comprises passing the light through a long-distance microscope lens attached to the camera.

14. The method of claim 1, performed for dynamic material deformation analysis by comparing a plurality of same diffraction order images.

15. The method of claim 1, performed for static object profile measurement by comparing a plurality of different diffraction order images.

16. The method of claim 15, wherein the plurality of images are taken with different exposure times.

17. The method of claim 1, further comprising outputting the three dimensional data in a computer-readable format.

18. A computer readable medium having stored instructions thereon that, when executed, cause at least one processor to:

receive input signals corresponding to a plurality of undistorted patterned images of an object, taken from different angles;

calculate, using a two-dimensional displacement measurement technique, a three dimensional profile of the target; and

output an output signal corresponding to the three dimensional profile of the target.

19. The computer readable medium of claim 18, wherein the pattern is selected from a grid pattern and a speckled pattern.

20. A three-dimensional imaging system for a target comprising:

at least one camera including a lens and a digital sensor;

a diffraction grating positioned between the at least one camera and a target to provide a plurality of views of the target from different angles; and

a computer processor connected with the sensor for processing captured digital sensor information for producing three-dimensional data of the target.

21. The system of claim 20, wherein the system includes only one camera.

22. The system of claim 20, wherein the diffraction grating is positioned relative to the at least one camera to allow image capture of the views without distortion.

23. The system of claim 20, wherein the diffraction grating is positioned relative to the at least one camera to allow image capture of the views without overlap.

24. The system of claim 20, wherein the grating comprises beam splitter grating.

25. The system of claim 20, wherein the grating comprises blazing grating.

26. The system of claim 25, further comprising a lighting source.

27. The system of claim 26, wherein the lighting source is positioned to transmit light through the target for imaging.

28. The system of claim 26, wherein the lighting source is positioned to reflect light from the target for imaging.

29. The system of claim 20, further comprising the target.

30. The system of claim 29, wherein the target is speckled.