Tracking system with scattering effect utilization, in particular with star effect and/or cross effect utilization

• US 20060089552A1
• Filed: 10/05/2005
• Published: 04/27/2006
• Est. Priority Date: 10/05/2004
• Status: Active Grant

• Current Assignee: Brainlab AG
• Original Assignee: Brainlab AG
• Inventors: Goldbach, Gunter
• Granted Patent: US 8,446,473 B2
• Time in Patent Office: Days
• US Class Current: 600/439
• CPC Class Codes: A61B 2017/00411 actuated by application of energy from an energy source outside the body
• CPC Class Codes: A61B 2034/2055 Optical tracking systems
• CPC Class Codes: A61B 2034/2065 Tracking using image or pattern recognition
• CPC Class Codes: A61B 2090/3937 Visible markers
• CPC Class Codes: A61B 2090/3945 Active visible markers, e.g. light emitting diodes
• CPC Class Codes: A61B 34/20 Surgical navigation systems; Devices for tracking or guiding surgical instruments, e.g. for frameless stereotaxis
• CPC Class Codes: A61B 5/06 Devices, other than using radiation, for detecting or locating foreign bodies for removing same A61B17/50 ; determining position of probes within or on the body of the patient
• CPC Class Codes: A61B 5/064 using markers A61B5/062 takes precedence
• CPC Class Codes: A61B 90/36 Image-producing devices or illumination devices not otherwise provided for

Abstract

An image generating device for an optical, in particular medical tracking system, for determining the position of a recorded image point, includes a light scattering effect generating device, in particular a star and/or cross effect generating device. The invention further provides a tracking system including such an image generating device and to a method for determining the position of a recorded image point using an optical, in particular medical tracking system, in which: an image is generated using an image generating device; a light scattering effect, in particular a star and/or cross effect, is generated on the image for predetermined image points; and in which the position of an image point is ascertained on the basis of the light scattering pattern projected on the image, in particular on the basis of the star and/or cross effect lines and/or their intersection points.

Claims

1. An image generating device for determining a position of a recorded image point in an optical tracking system, comprising:

a light scattering effect generating device.

2. The image generating device as set forth in claim 1, wherein the light scattering effect generating device is a star and/or cross effect generating device that generates star and/or cross effects in two distinct directions, the star and/or cross effects being at a predetermined angle with respect to each other.

3. The image generating device as set forth in claim 2, wherein the predetermined angle is substantially 90 degrees.

4. The image generating device as set forth in claim 1, wherein the light scattering effect generating device is a star and/or cross effect generating device that generates star and/or cross effects in at least three directions that are at a predetermined angle with respect to each other.

5. The image generating device of claim 4, wherein the predetermined angle is substantially 180 degrees divided by the number of directions.

6. The image generating device as set forth in claim 1, further comprising at least one camera including a light scattering effect filter arranged in front of, behind or on a lens of the camera.

7. The image generating device as set forth in claim 6, wherein the light scattering effect filter is a star and/or cross effect filter.

8. A system for tracking an object, comprising:

a medical tracking system; and

an image generating device as set forth in claim 1.

9. The tracking system as set forth in claim 8, further comprising an image processing unit that ascertains a position of an image point on the basis of a light scattering pattern

10. The tracking system as set forth in claim 9, wherein the light scattering pattern is star effect lines and/or their intersection points.

11. The tracking system as set forth in claim 8, further comprising:

an image generating device including at least two spaced cameras;

an image processing unit that ascertains a two-dimensional position of an image point recorded by each camera on the basis of a light scattering pattern and calculates a spatial position of the image point from the ascertained two-dimensional positions.

12. The tracking system as set forth in claim 11, wherein the light scattering pattern is star effect lines and/or their intersection points,

13. A method for determining a position of a recorded image point using an optical tracking system, comprising:

generating an image using an image generating device;

generating a light scattering effect on the image for predetermined image points; and

ascertaining the position of the image point on the basis of the light scattering pattern projected on the image.

14. The method of claim 13, wherein generating a light scattering effect includes using a star and/or cross effects, and wherein ascertaining the position of the image point includes using the star and/or cross effect lines and/or their intersection points.

15. The method as set forth in claim 14, further comprising taking into account prior known and predetermined angles of star and/or cross effect lines with respect to each other to determine the position of the image point.

16. The method as set forth in claim 14, wherein using the star and/or cross effects includes generating the star and/or cross effects in two directions that are at a predetermined angle with respect to each other.

17. The method of claim 16, wherein the predetermined angle is substantially 90 degrees.

18. The method as set forth in claim 14, wherein using star and/or cross effects includes generating the star and/or cross effects in at least three directions that are at a predetermined angle with respect to each other.

19. The method of claim 18, wherein the predetermined angle is substantially 180 degrees divided by the number of directions.

20. The method as set forth in claim 14, wherein using star and/or cross effects includes generating star and/or cross effects in at least a number of directions that exceeds the number of image points to be positionally ascertained by 1.

21. The method as set forth in claim 13, further comprising ascertaining the position of the image point on the basis of a brightness gradient of the light scattering pattern

22. The method of claim 21, wherein the light scattering pattern is star and/or cross effect lines.

23. The method as set forth in claim 13, further comprising determining the position of the image point on the basis of lines of the light scattering pattern having substantially the same brightness at an intersection point.