Automatic calibration of fourier-domain optical coherence tomography systems
A method for calibrating a Fourier domain optical coherence tomography system includes receiving spectral data from an optical detector comprising a linear array of detector elements, each detector element having a position labeled n, wherein detected light was wavelength-dispersed across the linear array of detector elements; determining parameters of a preselected functional relationship between wave number, kn, corresponding to detector element n as a function of optical detector element n based on the spectral data; further receiving subsequent spectral data subsequent to the first-mentioned receiving, wherein detected light was wavelength-dispersed across the linear array of detector elements; converting the subsequent spectral data using the preselected functional relationship between wave number kn and optical detector element n to obtain converted spectral data; and performing an inverse Fourier transform of the converted spectral data to obtain a depth profile.
1. A method for calibrating a Fourier domain optical coherence tomography system, comprising:
receiving spectral data from an optical detector comprising a linear array of detector elements, each detector element having a position labeled n, wherein detected light was wavelength-dispersed across said linear array of detector elements;
determining parameters of a preselected functional relationship between wave number, k n , corresponding to detector element n as a function of optical detector element n based on said spectral data;
further receiving subsequent spectral data subsequent to the first-mentioned receiving, wherein detected light was wavelength-dispersed across said linear array of detector elements;
converting said subsequent spectral data using said preselected functional relationship between wave number k n and optical detector element n to obtain converted spectral data; and
performing an inverse Fourier transform of said converted spectral data to obtain a depth profile.
2. The method of claim 1 , wherein said preselected functional relationship is a polynomial.
3. The method of claim 2 , wherein said preselected functional relationship is
k n =a 4 n 4 +a 3 n 3 +a 2 n 2 +a 1 n+a 0 ,
wherein said determining parameters is determining parameters a 0 , a 1 , a 2 , a 3 , and a 4 .
4. The method of claim 1 , wherein said determining parameters includes a zero crossing analysis of said spectral data.
5. The method of claim 1 , wherein said determining parameters includes an iterative process taking into account a sharpness of an interferogram based on said spectral data.
6. The method of claim 1 , further comprising calibrating a depth corresponding to each detector element of said linear array of detector elements.
7. The method of claim 6 , wherein said calibrating a depth comprises moving a reference of said Fourier domain optical coherence tomography system along a predefined path.
8. The method of claim 7 , wherein said predefined path is a substantially periodic path.
9. The method of claim 7 , wherein said predefined path is a substantially sinusoidal path.
10. A non-transitory computer readable medium comprising software, which software when executed by a computer causes the computer to:
receive spectral data from an optical detector comprising a linear array of detector elements, each detector element having a position labeled n, wherein detected light was wavelength-dispersed across said linear array of detector elements;
determine parameters of a preselected functional relationship between wave number, k n , corresponding to detector element n as a function of optical detector element n based on said spectral data;
further receive subsequent spectral data subsequent to the first-mentioned receiving, wherein detected light was wavelength-dispersed across said linear array of detector elements;
convert said subsequent spectral data using said preselected functional relationship between wave number k n and optical detector element n to obtain converted spectral data; and
perform an inverse Fourier transform of said converted spectral data to obtain a depth profile.
11. The computer readable medium of claim 10 , wherein said preselected functional relationship is a polynomial.
12. The computer readable medium of claim 11 , wherein said preselected functional relationship is
k n =a 4 n 4 +a 3 n 3 +a 2 n 2 +a 1 n+a 0 ,
wherein said determining parameters is determining parameters a 0 , a 1 , a 2 , a 3 , and a 4 .
13. The computer readable medium of claim 10 , wherein said determining parameters includes a zero crossing analysis of said spectral data.
14. The computer readable medium of claim 10 , wherein said determining parameters includes an iterative process taking into account a sharpness of an interferogram based on said spectral data.
15. The computer readable medium of claim 10 , wherein said software when executed by said computer further causes the computer to calibrate a depth corresponding to each detector element of said linear array of detector elements.
16. The computer readable medium of claim 15 , wherein said calibrating a depth comprises moving a reference of said Fourier domain optical coherence tomography system along a predefined path.
17. The computer readable medium of claim 16 , wherein said predefined path is a substantially periodic path.
18. The computer readable medium of claim 16 , wherein said predefined path is a substantially sinusoidal path.
19. An automatic spectral calibration optical coherence system, comprising:
a reference;
an optical probe;
a light source optically coupled to said optical probe;
a spectrometer detection system optically coupled to said optical probe; and
a computer constructed to communicate with said spectrometer detection system while in operation,
wherein said computer is configured to:
receive spectral data from an optical detector comprising a linear array of detector elements, each detector element having a position labeled n, wherein detected light was wavelength-dispersed across said linear array of detector elements;
determine parameters of a preselected functional relationship between wave number, k n , corresponding to detector element n as a function of optical detector element n based on said spectral data;
further receive subsequent spectral data subsequent to the first-mentioned receiving, wherein detected light was wavelength-dispersed across said linear array of detector elements;
convert said subsequent spectral data using said preselected functional relationship between wave number k n and optical detector element n to obtain converted spectral data; and
perform an inverse Fourier transform of said converted spectral data to obtain a depth profile.
20. The automatic spectral calibration optical coherence system of claim 19 , wherein said preselected functional relationship is a polynomial.
21. The automatic spectral calibration optical coherence system of claim 20 , wherein said preselected functional relationship is
k n =a 4 n 4 +a 3 n 3 +a 2 n 2 +a 1 n+a 0 ,
wherein said determining parameters is determining parameters a 0 , a 1 , a 2 , a 3 , and a 4 .
22. The automatic spectral calibration optical coherence system of claim 19 , wherein said determining parameters includes a zero crossing analysis of said spectral data.
23. The automatic spectral calibration optical coherence system of claim 19 , wherein said determining parameters includes an iterative process taking into account a sharpness of an interferogram based on said spectral data.
24. The automatic spectral calibration optical coherence system of claim 19 , wherein said software when executed by said computer further causes the computer to calibrate a depth corresponding to each detector element of said linear array of detector elements.
25. The automatic spectral calibration optical coherence system of claim 24 , wherein said calibrating a depth comprises moving a distal end of an optical probe of said Fourier domain optical coherence tomography system along a predefined path.
26. The automatic spectral calibration optical coherence system of claim 25 , wherein said predefined path is a substantially periodic path.
27. The automatic spectral calibration optical coherence system of claim 25 , wherein said predefined path is a substantially sinusoidal path.