System and method for integration of a calibration target into a C-Arm
View Patent ↗Certain embodiments of the present invention provide a method and system for improved calibration of an image acquisition device. Certain embodiments of the system include an image acquisition device for obtaining at least one image of an object and a calibration fixture positioned in relation to the image acquisition device. The calibration fixture includes a radiotranslucent material providing low frequency content for characterizing the image acquisition device. In an embodiment, the calibration fixture includes a plurality of peaks and valleys to create a low frequency signal for characterizing the image acquisition device. The calibration fixture may be positioned between the image acquisition device and an energy source such that a distance between the image acquisition device and the calibration fixture is minimized. In certain embodiments, a grating or other calibration fixture may be used to generate a moiré pattern to calibrate the image acquisition device.
1. A system facilitating calibration of an image acquisition device, said system comprising:
an image acquisition device for obtaining at least one image of an object;
a calibration fixture positioned in relation to said image acquisition device, wherein said calibration fixture includes a radiotranslucent material providing low frequency content for characterizing said image acquisition device; and
a filter configured to filter from the obtained image distortion due to the radiotranslucent material.
2. The system of claim 1 , wherein said calibration fixture includes at least one of density and thickness variations to create a low frequency signal for characterizing said image acquisition device.
3. The system of claim 1 , wherein said calibration fixture is positioned between said image acquisition device and an energy source such that a distance between said calibration fixture and said energy source is minimized.
4. The system of claim 1 , further comprising at least one tracking device for obtaining at least one of position and orientation data for said calibration fixture.
5. A method for calibration of an image acquisition system, said method comprising:
acquiring image data of a radiotranslucent calibration fixture located near an image acquisition device;
calibrating said image acquisition device using image data of said calibration; and
filtering from the acquired image data distortion due to said radiotranslucent calibration fixture.
6. The method of claim 5 , further comprising acquiring tracking data using at least one tracking device located on said calibration fixture.
7. The method of claim 5 , further comprising modeling said image acquisition device using said image data from said calibration fixture.
8. The method of claim 5 , further comprising analyzing said image data of said calibration fixture in a frequency domain.
9. The method of claim 8 , further comprising translating said image data from said frequency domain to a spatial domain.
10. The method of claim 5 , further comprising analyzing said image data from said calibration fixture using a Fourier analysis.
11. The method of claim 5 , wherein said calibration fixture generates low frequency data used to calibrate said image acquisition device.
12. The method of claim 5 , further comprising characterizing said image acquisition device to improve registration between points in an image reference frame and points in a tracking reference frame.
13. The method of claim 5 , further comprising processing said image data obtained using said image acquisition device to reduce image artifacts.
14. A calibration device for calibrating an imaging system, said calibration device comprising:
a radiotranslucent calibration fixture capable of creating a characterization frequency used in calibrating an image acquisition device;
a positioning device for positioning said radiotranslucent calibration fixture with respect to said image acquisition device; and
a filtering device for filtering from an acquired image distortion due to the radiotranslucent calibration fixture.
15. The calibration device of claim 14 , wherein said radiotranslucent calibration fixture generates low frequency data used in calibrating an image acquisition device.
16. The calibration device of claim 14 , wherein said radiotranslucent calibration fixture comprises at least one of density and thickness variations to generate a distinctive characterization pattern.
17. A calibration device for calibrating an imaging system, said calibration device comprising:
a calibration fixture capable of creating a characterization frequency used in calibrating an image acquisition device, said calibration fixture generating a low frequency pattern used in calibrating said image acquisition device;
a processor configured to model said image acquisition device using data from said low frequency pattern generated by said calibration fixture;
a positioning device for positioning said calibration fixture with respect to said image acquisition device; and
a filtering device for filtering from an acquired image distortion due to the calibration fixture.
18. The calibration device of claim 17 , wherein said calibration fixture includes a radiotranslucent material providing low frequency content for characterizing said image acquisition device.
19. The calibration device of claim 17 , wherein said calibration fixture generates low frequency data used in calibrating said image acquisition device.
20. The calibration device of claim 17 , wherein said calibration fixture comprises a wavy panel.
21. The calibration device of claim 20 , wherein the wavy panel includes a plurality of peaks and valleys configured to produce a low frequency calibration response.
22. The calibration device of claim 17 , wherein said calibration fixture comprises at least one of density and thickness variations to generate a distinctive characterization pattern.
23. The calibration device of claim 17 , wherein said calibration fixture is positioned between said image acquisition device and an energy source such that the distance between said calibration fixture and said energy source in minimized.