频域光学相干层析术系统中高准确度高灵敏度补偿色散法
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摘要
将色散测量方法和快速扫描延迟线技术相结合,在谱域光学相干层析系统中实现了对群延迟色散的精确补偿.在该方法中,先在样品臂中放入平面反射镜,等间隔移动参考臂中快速扫描延迟线系统中光栅的位置,同时测量系统参考臂和样品臂之间的群延迟色散差值.当该值为零时,则表明系统色散匹配.将该方法与基于点扩散函数半高宽的方法进行比较,发现基于半高宽方法的测量误差为4.43%,而该方法的测量误差为0.76%;在色散补偿过程中,随着色散匹配点的靠近,半高宽方法的灵敏度由92.105 3fs2减小到1.344 7×103 fs2,而新方法的灵敏度则保持165.789 5fs2,表明本文提出的色散补偿法具有较高的色散补偿准确度和灵敏度.实验表明,色散补偿后的系统分辨率接近理论值;在补偿系统色散的同时,还可以根据测量所得色散值的符号来判定光栅的移动方向,从而更容易地完成补偿工作.
A method of compensating dispersion precisely in Fourier domain optical coherence tomography was proposed,based on the combination of the measurements of the values of the dispersion with the rapid scanning optical delay line.Firstly,aplane mirror was placed in the sample arm,and the values of differences of the group delay dispersion were measured while moving the grating in rapid scanning optical delay line to introduce differentdispersion.When the measured value was zero,the dispersion was matched.The new method was compared with the one based on the full width at half maxmum of point spread function.It was found that the measuring error of full width at half maxmum was 4.43% while proposed method was 0.76% and the sensitivity of full width at half the maxmum decreased from 92.105 3fs2 to 1.344 7×103 fs2 while it remained 165.789 5fs2 in the proposed method.The results show that this method is more accurate and sensitive than the full width at half the maximum.In addition,the direction of grating movement can be determined by the sign of the measured value of dispersion difference,which may be used to compensate dispersion.Finally,the experimental data show that the axial resolution after compensating dispersion nearly approaches the theoretical value.
A method of compensating dispersion precisely in Fourier domain optical coherence tomography was proposed,based on the combination of the measurements of the values of the dispersion with the rapid scanning optical delay line.Firstly,aplane mirror was placed in the sample arm,and the values of differences of the group delay dispersion were measured while moving the grating in rapid scanning optical delay line to introduce differentdispersion.When the measured value was zero,the dispersion was matched.The new method was compared with the one based on the full width at half maxmum of point spread function.It was found that the measuring error of full width at half maxmum was 4.43% while proposed method was 0.76% and the sensitivity of full width at half the maxmum decreased from 92.105 3fs2 to 1.344 7×103 fs2 while it remained 165.789 5fs2 in the proposed method.The results show that this method is more accurate and sensitive than the full width at half the maximum.In addition,the direction of grating movement can be determined by the sign of the measured value of dispersion difference,which may be used to compensate dispersion.Finally,the experimental data show that the axial resolution after compensating dispersion nearly approaches the theoretical value.
引文
[1]HUANG D,SWANSON E A,LIN C P,et al.Optical coherence tomography[J].Science,1991,254(5035):1178-1181.
[2]GAO Ying-jun,JIN Chong-xin,LIN Lin,et al.Measurement of optical properties of highly scattering media by optical coherence tomography[J].Acta Photonica Sinica,2011,40(1):98-102.高应俊,金重星,林林,等.基于光学相干层析成像技术的强散射介质光学特性测量[J].光子学报,2011,40(1):98-102.
[3]WANG Kai,DING Zhi-hua,WANG Ling.Measuring tissue optical properties by optical coherence tomography[J].Acta Photonica Sinica,2008,37(3):523-527.王凯,丁志华,王玲.基于光学相干层析术的组织光学性质测量[J].光子学报,2008,37(3):523-527.
[4]WOJTKOWSKI M,SRINIVASAN V,KO T,et al.Ultrahigh-resolution,high-speed,Fourier domain optical coherence tomography and methods for dispersion compensation[J].Optics Express,2004,12(11):2404-2422.
[5]DEBOER J F,CENSE B,PARK B H,et al.Improved signaltonoise ratio in spectral-domain compared with time-domain optical coherence tomography[J].Optics letters,2003,28(21):2067-2069.
[6]ZHANG Xian-ling,GAO Wan-rong,BIAN Hai-yi,et al.Study of de-noising based on empirical mode decompositon method in optical coherence tomography[J].Journal of Optoelectronics·Laser,2012,23(3):602-608.张仙玲,高万荣,卞海溢,等.基于经验模式分解法的光学相干层析成像去噪研究[J].光电子·激光,2012,23(3):602-608.
[7]LI Peng,GAO Wan-rong.Dispersion extraction with optical coherence tomography:a pilot study[J].Acta Photonica Sinica,2009,38(10):2598-2602.李鹏,高万荣.光学相干层析术提取色散信息的初步研究[J].光子学报,2009,38(10):2598-2602.
[8]LI Cheng-shuai,SHEN Wei-dong,ZHANGYue-guangr,et al.Measurement of group delay dispersion of dispersive mirror based on white-light interference[J].Acta Optica Sinica,2012,32(10):287-292.李承帅,沈伟东,章岳光,等.基于白光干涉测量色散补偿薄膜的群延迟色散[J].光学学报,2012,32(10):287-292.
[9]CHEN Chao-liang,GAO Wan-rong.Spectral fiber low coherence interferometry-based method of measuring dispersion and refractive index of transparent object[J].Chinese Journal of Laser,2013,40(10):1008005.陈朝良,高万荣.基于光谱光纤低相干的透射样品色散和折射率测量方法[J].中国激光,2013,40(10):1008005.
[10]DONG Jin-tao,LU Rong-sheng.Dispersion compensation based on frequency domain analysis in optical coherence microscopy[J].Chinese Journal of Laser,2012,39(1):235-240.董敬涛,卢荣胜.基于频域分析的光学相干显微镜中的色散补偿[J].中国激光,2012,39(1):235-240.
[11]GAO W.Dispersion properties of grating-based rapid scanning optical delay lines[J].Applied Optics,2007,46(6):986-992.
[12]FERCHER A,HITZENBERGER C,STICKER M,et al.Numerical dispersion compensation for partial coherence interferometry and optical coherence tomography[J].Optics Express,2001,9(12):610-615.
[13]XIE T,WANG Z,PAN Y.Dispersion compensation in highspeed optical coherence tomography by acousto-optic modulation[J].Applied Optics,2005,44(20):4272-4280.
[14]MEADWAY A,DARBRAZI S H H,DOBRE G,et al.A rapid method of measuring dispersion in low coherence interferometry and optical coherence tomography systems[J].Journal of Optics,2010,12(1):015302.
[15]SORIN W V,GRAY D F.Simultaneous thickness and group index measurement using optical low-coherence reflectometry[J].IEEE Photonics Technology Letters,1992,4(1):105-107.
[2]GAO Ying-jun,JIN Chong-xin,LIN Lin,et al.Measurement of optical properties of highly scattering media by optical coherence tomography[J].Acta Photonica Sinica,2011,40(1):98-102.高应俊,金重星,林林,等.基于光学相干层析成像技术的强散射介质光学特性测量[J].光子学报,2011,40(1):98-102.
[3]WANG Kai,DING Zhi-hua,WANG Ling.Measuring tissue optical properties by optical coherence tomography[J].Acta Photonica Sinica,2008,37(3):523-527.王凯,丁志华,王玲.基于光学相干层析术的组织光学性质测量[J].光子学报,2008,37(3):523-527.
[4]WOJTKOWSKI M,SRINIVASAN V,KO T,et al.Ultrahigh-resolution,high-speed,Fourier domain optical coherence tomography and methods for dispersion compensation[J].Optics Express,2004,12(11):2404-2422.
[5]DEBOER J F,CENSE B,PARK B H,et al.Improved signaltonoise ratio in spectral-domain compared with time-domain optical coherence tomography[J].Optics letters,2003,28(21):2067-2069.
[6]ZHANG Xian-ling,GAO Wan-rong,BIAN Hai-yi,et al.Study of de-noising based on empirical mode decompositon method in optical coherence tomography[J].Journal of Optoelectronics·Laser,2012,23(3):602-608.张仙玲,高万荣,卞海溢,等.基于经验模式分解法的光学相干层析成像去噪研究[J].光电子·激光,2012,23(3):602-608.
[7]LI Peng,GAO Wan-rong.Dispersion extraction with optical coherence tomography:a pilot study[J].Acta Photonica Sinica,2009,38(10):2598-2602.李鹏,高万荣.光学相干层析术提取色散信息的初步研究[J].光子学报,2009,38(10):2598-2602.
[8]LI Cheng-shuai,SHEN Wei-dong,ZHANGYue-guangr,et al.Measurement of group delay dispersion of dispersive mirror based on white-light interference[J].Acta Optica Sinica,2012,32(10):287-292.李承帅,沈伟东,章岳光,等.基于白光干涉测量色散补偿薄膜的群延迟色散[J].光学学报,2012,32(10):287-292.
[9]CHEN Chao-liang,GAO Wan-rong.Spectral fiber low coherence interferometry-based method of measuring dispersion and refractive index of transparent object[J].Chinese Journal of Laser,2013,40(10):1008005.陈朝良,高万荣.基于光谱光纤低相干的透射样品色散和折射率测量方法[J].中国激光,2013,40(10):1008005.
[10]DONG Jin-tao,LU Rong-sheng.Dispersion compensation based on frequency domain analysis in optical coherence microscopy[J].Chinese Journal of Laser,2012,39(1):235-240.董敬涛,卢荣胜.基于频域分析的光学相干显微镜中的色散补偿[J].中国激光,2012,39(1):235-240.
[11]GAO W.Dispersion properties of grating-based rapid scanning optical delay lines[J].Applied Optics,2007,46(6):986-992.
[12]FERCHER A,HITZENBERGER C,STICKER M,et al.Numerical dispersion compensation for partial coherence interferometry and optical coherence tomography[J].Optics Express,2001,9(12):610-615.
[13]XIE T,WANG Z,PAN Y.Dispersion compensation in highspeed optical coherence tomography by acousto-optic modulation[J].Applied Optics,2005,44(20):4272-4280.
[14]MEADWAY A,DARBRAZI S H H,DOBRE G,et al.A rapid method of measuring dispersion in low coherence interferometry and optical coherence tomography systems[J].Journal of Optics,2010,12(1):015302.
[15]SORIN W V,GRAY D F.Simultaneous thickness and group index measurement using optical low-coherence reflectometry[J].IEEE Photonics Technology Letters,1992,4(1):105-107.