Structured light imaging apparatus

• US 20050237423A1
• Filed: 05/11/2005
• Published: 10/27/2005
• Est. Priority Date: 07/13/2001
• Status: Active Grant

• Current Assignee: Xenogen Corporation (Revvity, Inc.)
• Original Assignee: Xenogen Corporation (Revvity, Inc.)
• Inventors: Rice, Bradley W., Cable, Michael D., Nilson, David, Kearney, Kevin
• Granted Patent: US 7,298,415 B2
• Time in Patent Office: Days
• US Class Current: 348/370
• CPC Class Codes: A61B 1/0605 for spatially modulated illumination
• CPC Class Codes: A61B 2503/40 Animals
• CPC Class Codes: A61B 5/0059 using light, e.g. diagnosis by transillumination, diascopy, fluorescence A61B5/0093, A61B5/1455, A61B5/02416 and A61B5/0261 take precedence
• CPC Class Codes: A61B 5/0064 Body surface scanning
• CPC Class Codes: A61B 5/107 Measuring physical dimensions, e.g. size of the entire body or parts thereof
• CPC Class Codes: A61B 5/6888 Cabins
• CPC Class Codes: G01B 11/2513 with several lines being projected in more than one direction, e.g. grids, patterns
• CPC Class Codes: G01B 11/2518 Projection by scanning of the object
• CPC Class Codes: G01N 21/6456 Spatial resolved fluorescence measurements; Imaging
• CPC Class Codes: G01N 21/763 Bioluminescence
• CPC Class Codes: G06T 7/521 from laser ranging, e.g. using interferometry; from the projection of structured light
• CPC Class Codes: H04N 13/254 in combination with electromagnetic radiation sources for illuminating objects

Abstract

The present invention integrates a structured light source into an imaging system for reconstructing surface topography of an object being imaged. The structured light source includes a mechanism for transmitting a set of lines onto the object from an angle. The lines are displaced, or phase shifted relative to a stage, when they encounter an object with finite height, such as a mouse. This phase shift provides structured light information for the object. A camera captures the structured light information. Using software that employs a structured light analysis, surface topography data for the object is determined from the phase shift of the lines.

Claims

1. An imaging system for providing a three-dimensional surface representation of an animal, the imaging system comprising:

an imaging chamber including a set of walls enclosing an interior cavity and including a camera mount configured to position a camera;

a stage configured to support the animal within the interior cavity and within a field of view for the camera;

a structured light source configured to produce structured light for transmission onto the animal while the animal rests on the stage, wherein interception of the structured light by the animal generates structured light surface information for the animal; and

a processor configured to produce a three-dimensional surface representation of at least a portion of the animal using the structured light surface information obtained by the camera.

2. The system of claim 1 wherein the structured light source comprises a structured light projector configured to produce the structured light.

3. The system of claim 1 wherein the structured light source is configured to transmit a grid of lines onto the animal.

4. The system of claim 3 wherein the structured light projector projects the grid of lines onto the animal from an angle.

5. The system of claim 3 wherein the grid of lines having a line spacing in the range of about 0.5 to about 2 lines per millimeter.

6. The system of claim 1 further comprising a light transport device that transmits light emitted from a surface of the animal to the camera.

7. The system of claim 6 wherein the structured light source is coupled to the light transport device.

8. The system of claim 7 wherein the light transport device comprises a mirror configured to intercept light emitted from the animal before receipt by the camera.

9. The system of claim 8 further comprising a fixed datum that passes though the camera mount and perpendicular to a vertical wall of the imaging chamber.

10. The system of claim 9 wherein the light transport device is configured to rotate about the fixed datum.

11. The system of claim 10 wherein the structured light source is coupled to the light transport device and rotates with the light transport device about the fixed datum.

12. The system of claim 1 wherein the stage is moveable to one of a plurality of positions in the interior cavity.

13. The system of claim 1 wherein the processor is further configured to produce the three-dimensional surface representation of the animal using instructions stored in memory that determine how to produce the three-dimensional surface representation from the structured light surface information.

14. The system of claim 1 wherein the set of walls enclose the interior cavity such that the imaging chamber is substantially light tight.

15. The system of claim 1 wherein the structured light source comprises a scanning laser galvanometer that includes:

a laser that produces a beam of light; and

at least one mirror positionable to reflect the beam of light and cast a grid of lines onto the animal,

wherein the grid of lines has a line spacing in the range of about 0.5 to about 2 lines per millimeter.

16. The system of claim 15 wherein the scanning light galvanometer is disposed above the stage and reflects the beam of light down onto a top surface of the animal.

17. The system of claim 1 wherein the structured light source comprises a scanning laser galvanometer that casts structured light at an angle from about 15°

and about 30°

relative to a surface normal of the stage.

18. An imaging system for providing a three-dimensional representation of an animal, the imaging system comprising:

an imaging chamber including a set of walls enclosing an interior cavity and including a camera mount configured to position a camera;

a moveable stage apparatus including a transport mechanism and a stage configured to support the animal within the interior cavity, the stage being coupled with the transport mechanism for movement of the animal to one of a plurality of positions in the interior cavity; and

a structured light source configured to produce structured light for transmission onto the animal while the animal rests on the stage to generate structured light surface information for the animal; and

a processor configured to produce a three-dimensional surface representation of the animal using the structured light surface information obtained by the camera.

19. The system of claim 18 wherein the structured light source comprises a scanning laser galvanometer that includes:

a laser that produces a beam of light; and

a mirror positionable to reflect the beam of light and cast a grid of lines onto the animal.

20. The system of claim 19 wherein the scanning light galvanometer is disposed above the stage and reflects the beam of light down onto a top surface of the animal.

21. The system of claim 18 wherein the structured light source comprises a structured light projector configured to produce the structured light.

22. The system of claim 21 wherein the structured light projector is configured to project a grid of lines onto the animal.

23. The system of claim 22 wherein the structured light projector projects the grid of lines onto the animal from an angle.

24. The system of claim 18 wherein the imaging chamber is substantially light tight.

25. An imaging system for providing a three-dimensional surface representation of an animal, the imaging system comprising:

an imaging chamber including a set of walls enclosing an interior cavity and including a camera mount configured to position a camera;

a stage configured to support the animal within the interior cavity and within a field of view for the camera;

a structured light source configured to produce a grid of light lines for transmission onto the animal while the animal rests on the stage to generate structured light surface information for the animal; and

a processor configured to produce a three-dimensional surface representation of the animal using the structured light surface information obtained by the camera.

26. The system of claim 25 wherein the structured light source transmits the grid of lines onto the animal from an angle.

27. The system of claim 25 wherein the structured light source projects a set of grid of lines having a line spacing in the range of about 0.5 to about 2 lines per mm.

28. The system of claim 25 wherein the set of walls enclose the interior cavity such that the imaging chamber is substantially light tight.

29. The system of claim 25 wherein the structured light source is a structured light projector that projects the grid of lines.