Spectral domain polarization-sensitive optical coherence tomography （SDPS-OCT） is a depth-resolved polarization-sensitive interferometry which integrates polarization optics into spectral domain optical co- herence ...Spectral domain polarization-sensitive optical coherence tomography （SDPS-OCT） is a depth-resolved polarization-sensitive interferometry which integrates polarization optics into spectral domain optical co- herence tomography （SD-OCT）. This configuration can obtain birefringence information of samples and improve the imaging speed. In this paper, horizontally polarized light is used to replace natural light of the source. Then, right-rotated circularly polarized light is the incident sample light. To obtain two orthogonal components of the polarized interferogram, the reflected light of the reference arm is set to be 45° linearly polarized light. These two components are acquired by two spectrometers synchronously. The system was employed to achieve 12.8μm axial resolution and 4.36μm transverse resolution. We have imaged in vitro chicken tendon and muscle tissues with these svstem.展开更多
Optical interferometry is a powerful tool for measuring and characterizing areal surface topography in precision manufacturing.A variety of instruments based on optical interferometry have been developed to meet the m...Optical interferometry is a powerful tool for measuring and characterizing areal surface topography in precision manufacturing.A variety of instruments based on optical interferometry have been developed to meet the measurement needs in various applications,but the existing techniques are simply not enough to meet the ever-increasing requirements in terms of accuracy,speed,robustness,and dynamic range,especially in on-line or on-machine conditions.This paper provides an in-depth perspective of surface topography reconstruction for optical interferometric measurements.Principles,configurations,and applications of typical optical interferometers with different capabilities and limitations are presented.Theoretical background and recent advances of fringe analysis algorithms,including coherence peak sensing and phase-shifting algorithm,are summarized.The new developments in measurement accuracy and repeatability,noise resistance,self-calibration ability,and computational efficiency are discussed.This paper also presents the new challenges that optical interferometry techniques are facing in surface topography measurement.To address these challenges,advanced techniques in image stitching,on-machine measurement,intelligent sampling,parallel computing,and deep learning are explored to improve the functional performance of optical interferometry in future manufacturing metrology.展开更多
Background:Cataract surgery is the most common surgical procedure in ophthalmology.Biometry data and accurate intraocular lens(IOL)calculations are very important in achieving the desired refractive outcomes.The aim o...Background:Cataract surgery is the most common surgical procedure in ophthalmology.Biometry data and accurate intraocular lens(IOL)calculations are very important in achieving the desired refractive outcomes.The aim of this study was to compare measurements using a new optical low coherence reflectometry(OLCR)biometer(OA-2000)and the gold standard partial coherence interferometry(PCI)optical biometer(IOLMaster 500).Methods:Ocular biometry of cataract patients were measured by the OA-2000 and IOLMaster 500 to compare keratometry(K),axial length(AL),anterior chamber depth(ACD),white-to-white(WTW)diameter,and IOL power using the SRK/T formula.Results:One hundred and two eyes of 68 cataract patients were evaluated with the two optical biometers.The mean values of the AL,K,ACD,and WTW differed very little(OCLR biometer,23.12 mm,44.50 diopters(D),3.06,and 11.64 mm,respectively;PCI biometer,23.18 mm,44.6 D,3.15,and 11.86 mm,respectively),but the differences were significant(all,p≤0.05).The AL,K,and ACD showed excellent correlations(r=0.999,0.980,and 0.824,respectively;all p<0.001);however,there was a weak correlation of the WTW diameter between the two devices(r=0.256).The IOL powers using the SRK-T formula derived from both instruments were very similar,with an excellent correlation(r=0.989).The mean difference between the two instruments was 0.32 D.Conclusions:The OLCR biometer showed very a strong agreement with the standard PCI optical biometer for almost all ocular biometry measurements,except for the WTW diameter.Trial registration:TCTR20160614003;date 06/09/2016;‘retrospectively registered’.展开更多
文摘Spectral domain polarization-sensitive optical coherence tomography （SDPS-OCT） is a depth-resolved polarization-sensitive interferometry which integrates polarization optics into spectral domain optical co- herence tomography （SD-OCT）. This configuration can obtain birefringence information of samples and improve the imaging speed. In this paper, horizontally polarized light is used to replace natural light of the source. Then, right-rotated circularly polarized light is the incident sample light. To obtain two orthogonal components of the polarized interferogram, the reflected light of the reference arm is set to be 45° linearly polarized light. These two components are acquired by two spectrometers synchronously. The system was employed to achieve 12.8μm axial resolution and 4.36μm transverse resolution. We have imaged in vitro chicken tendon and muscle tissues with these svstem.
基金funding from the Enterprise Ireland and from the European Union’s Horizon 2020 Research and Innovation Programme under the Marie Skłodowska-Curie grant agreement(Grant No.713654)the National Natural Science Foundation of China(Grant No.51705070)the Science Foundation Ireland(SFI)(Grant No.15/RP/B3208).
文摘Optical interferometry is a powerful tool for measuring and characterizing areal surface topography in precision manufacturing.A variety of instruments based on optical interferometry have been developed to meet the measurement needs in various applications,but the existing techniques are simply not enough to meet the ever-increasing requirements in terms of accuracy,speed,robustness,and dynamic range,especially in on-line or on-machine conditions.This paper provides an in-depth perspective of surface topography reconstruction for optical interferometric measurements.Principles,configurations,and applications of typical optical interferometers with different capabilities and limitations are presented.Theoretical background and recent advances of fringe analysis algorithms,including coherence peak sensing and phase-shifting algorithm,are summarized.The new developments in measurement accuracy and repeatability,noise resistance,self-calibration ability,and computational efficiency are discussed.This paper also presents the new challenges that optical interferometry techniques are facing in surface topography measurement.To address these challenges,advanced techniques in image stitching,on-machine measurement,intelligent sampling,parallel computing,and deep learning are explored to improve the functional performance of optical interferometry in future manufacturing metrology.
文摘Background:Cataract surgery is the most common surgical procedure in ophthalmology.Biometry data and accurate intraocular lens(IOL)calculations are very important in achieving the desired refractive outcomes.The aim of this study was to compare measurements using a new optical low coherence reflectometry(OLCR)biometer(OA-2000)and the gold standard partial coherence interferometry(PCI)optical biometer(IOLMaster 500).Methods:Ocular biometry of cataract patients were measured by the OA-2000 and IOLMaster 500 to compare keratometry(K),axial length(AL),anterior chamber depth(ACD),white-to-white(WTW)diameter,and IOL power using the SRK/T formula.Results:One hundred and two eyes of 68 cataract patients were evaluated with the two optical biometers.The mean values of the AL,K,ACD,and WTW differed very little(OCLR biometer,23.12 mm,44.50 diopters(D),3.06,and 11.64 mm,respectively;PCI biometer,23.18 mm,44.6 D,3.15,and 11.86 mm,respectively),but the differences were significant(all,p≤0.05).The AL,K,and ACD showed excellent correlations(r=0.999,0.980,and 0.824,respectively;all p<0.001);however,there was a weak correlation of the WTW diameter between the two devices(r=0.256).The IOL powers using the SRK-T formula derived from both instruments were very similar,with an excellent correlation(r=0.989).The mean difference between the two instruments was 0.32 D.Conclusions:The OLCR biometer showed very a strong agreement with the standard PCI optical biometer for almost all ocular biometry measurements,except for the WTW diameter.Trial registration:TCTR20160614003;date 06/09/2016;‘retrospectively registered’.
