Purpose:To assess the repeatability and reproducibility of swept-source optical coherence tomography(SS-OCT)and Scheimpflug system and evaluate the agreement between the two systems in measuring multiple corneal regio...Purpose:To assess the repeatability and reproducibility of swept-source optical coherence tomography(SS-OCT)and Scheimpflug system and evaluate the agreement between the two systems in measuring multiple corneal regions in children.Methods:Pachymetric and keratometric maps for both systems were evaluated.Central,midperipheral and peripheral corneal thickness(CT),keratometry and astigmatism power vectors were recorded.The three outcomes yielded by the same observer were used to assess intraobserver repeatability.The differences in the mean values provided by each observer were used to evaluate interobserver reproducibility.Within-subject standard deviation,test-retest repeatability(TRT)and coefficient of variation(CoV)were used to analyze the intraobserver repeatability and interobserver reproducibility.Paired T-test and Bland-Altman were used to appraise interdevice agreement.Results:Seventy-eight eyes of 78 children were included.The CoV was≤2.12 and 1.10%,respectively,for repeatability and reproducibility.TRT and CoV were lower for central and paracentral CT measurements than for peripheral measurements.The SS-OCT device generated higher precision when acquiring CT data,whereas Scheimpflug system showed higher reliability when measuring corneal keratometry.Although the CT readings measured using SS-OCT were significantly thinner than Scheimpflug device(P<0.001),the central and thinnest CT values were still of high agreement.The interdevice agreement of keratometry measurement was high for the central corneal region and moderate for the paracentral and peripheral areas.Conclusions:The precision of CT measurements by SS-OCT was higher,while the reliability of keratometry measurements by the Scheimpflug system was higher in children.Apart from the measured values in the central corneal region,the thickness and keratometry readings should not be considered interchangeable between the two systems.展开更多
Optical resonators with controllable Q factors are key components in many areas of optical physics and engineering.We propose and investigate a Q-factor controllable system composed of two directly coupled microring r...Optical resonators with controllable Q factors are key components in many areas of optical physics and engineering.We propose and investigate a Q-factor controllable system composed of two directly coupled microring resonators,one of which is tunable and coupled to dual waveguides.By shifting the resonance of the controllable microring,the Q factor of the system as well as the other microring changes significantly.We have demonstrated wide-range controllable Q factors based on this structure in silicon-on-insulator,for example.The influences of spectral detuning and coupling strength between two resonators on the variation of Q factors are studied in detail experimentally.Then,we explore its applications in optical buffering.Tunable fast-to-slow/slow-to-fast light has been carried out by switching the system between the high-Q state and low-Q state.Moreover,optical pulse capture and release are also achievable using this structure with dynamic tuning,and the photon storage properties are investigated.The proposed Q-factor tunable system is simple,flexible,and realizable in various integrated photonic platforms,allowing for potential applications in on-chip optical communications and quantum information processing.展开更多
Purpose:To assess the repeatability and reproducibility of swept-source optical coherence tomography(SS-OCT)and Scheimpflug system and evaluate the agreement between the two systems in measuring multiple corneal regio...Purpose:To assess the repeatability and reproducibility of swept-source optical coherence tomography(SS-OCT)and Scheimpflug system and evaluate the agreement between the two systems in measuring multiple corneal regions in children.Methods:Pachymetric and keratometric maps for both systems were evaluated.Central,midperipheral and peripheral corneal thickness(CT),keratometry and astigmatism power vectors were recorded.The three outcomes yielded by the same observer were used to assess intraobserver repeatability.The differences in the mean values provided by each observer were used to evaluate interobserver reproducibility.Within-subject standard deviation,test-retest repeatability(TRT)and coefficient of variation(CoV)were used to analyze the intraobserver repeatability and interobserver reproducibility.Paired T-test and Bland-Altman were used to appraise interdevice agreement.Results:Seventy-eight eyes of 78 children were included.The CoV was≤2.12 and 1.10%,respectively,for repeatability and reproducibility.TRT and CoV were lower for central and paracentral CT measurements than for peripheral measurements.The SS-OCT device generated higher precision when acquiring CT data,whereas Scheimpflug system showed higher reliability when measuring corneal keratometry.Although the CT readings measured using SS-OCT were significantly thinner than Scheimpflug device(P<0.001),the central and thinnest CT values were still of high agreement.The interdevice agreement of keratometry measurement was high for the central corneal region and moderate for the paracentral and peripheral areas.Conclusions:The precision of CT measurements by SS-OCT was higher,while the reliability of keratometry measurements by the Scheimpflug system was higher in children.Apart from the measured values in the central corneal region,the thickness and keratometry readings should not be considered interchangeable between the two systems.展开更多
基金This work was supported in part by the Medical and Health Science and Technology Program of Zhejiang Province(2019KY111)Foundation of Wenzhou City Science&Technology Bureau(Y20180174)+3 种基金Zhejiang Provincial Key Research and Development Program(2018C03012)Zhejiang Provincial High-level Talents Program(2017–102)Wenzhou Key Team of Scientific and Technological Innovation(C20170002)The contribution from the G.B.Bietti Foundation was supported by the Italian Ministry of Health and Fondazione Roma.
文摘Purpose:To assess the repeatability and reproducibility of swept-source optical coherence tomography(SS-OCT)and Scheimpflug system and evaluate the agreement between the two systems in measuring multiple corneal regions in children.Methods:Pachymetric and keratometric maps for both systems were evaluated.Central,midperipheral and peripheral corneal thickness(CT),keratometry and astigmatism power vectors were recorded.The three outcomes yielded by the same observer were used to assess intraobserver repeatability.The differences in the mean values provided by each observer were used to evaluate interobserver reproducibility.Within-subject standard deviation,test-retest repeatability(TRT)and coefficient of variation(CoV)were used to analyze the intraobserver repeatability and interobserver reproducibility.Paired T-test and Bland-Altman were used to appraise interdevice agreement.Results:Seventy-eight eyes of 78 children were included.The CoV was≤2.12 and 1.10%,respectively,for repeatability and reproducibility.TRT and CoV were lower for central and paracentral CT measurements than for peripheral measurements.The SS-OCT device generated higher precision when acquiring CT data,whereas Scheimpflug system showed higher reliability when measuring corneal keratometry.Although the CT readings measured using SS-OCT were significantly thinner than Scheimpflug device(P<0.001),the central and thinnest CT values were still of high agreement.The interdevice agreement of keratometry measurement was high for the central corneal region and moderate for the paracentral and peripheral areas.Conclusions:The precision of CT measurements by SS-OCT was higher,while the reliability of keratometry measurements by the Scheimpflug system was higher in children.Apart from the measured values in the central corneal region,the thickness and keratometry readings should not be considered interchangeable between the two systems.
基金National Key Research and Development Program of China(2019YFB2203101)National Natural Science Foundation of China(61675084,61775094)State Key Laboratory of Advanced Optical Communication Systems and Networks(2021GZKF006).
文摘Optical resonators with controllable Q factors are key components in many areas of optical physics and engineering.We propose and investigate a Q-factor controllable system composed of two directly coupled microring resonators,one of which is tunable and coupled to dual waveguides.By shifting the resonance of the controllable microring,the Q factor of the system as well as the other microring changes significantly.We have demonstrated wide-range controllable Q factors based on this structure in silicon-on-insulator,for example.The influences of spectral detuning and coupling strength between two resonators on the variation of Q factors are studied in detail experimentally.Then,we explore its applications in optical buffering.Tunable fast-to-slow/slow-to-fast light has been carried out by switching the system between the high-Q state and low-Q state.Moreover,optical pulse capture and release are also achievable using this structure with dynamic tuning,and the photon storage properties are investigated.The proposed Q-factor tunable system is simple,flexible,and realizable in various integrated photonic platforms,allowing for potential applications in on-chip optical communications and quantum information processing.
基金supported in part by the Medical and Health Science and Technology Program of Zhejiang Province(2019kY111)Foundation of Wenzhou City Science&Technology Bureau(Y20180174)+2 种基金Zhejiang Provincial Key Researchand Development Program(2018C03012)Zhejiang Provincial High-level Talents Program(2017-102)WenzhouKey Teamof Scientific and Technological Innovation(C20170002).
文摘Purpose:To assess the repeatability and reproducibility of swept-source optical coherence tomography(SS-OCT)and Scheimpflug system and evaluate the agreement between the two systems in measuring multiple corneal regions in children.Methods:Pachymetric and keratometric maps for both systems were evaluated.Central,midperipheral and peripheral corneal thickness(CT),keratometry and astigmatism power vectors were recorded.The three outcomes yielded by the same observer were used to assess intraobserver repeatability.The differences in the mean values provided by each observer were used to evaluate interobserver reproducibility.Within-subject standard deviation,test-retest repeatability(TRT)and coefficient of variation(CoV)were used to analyze the intraobserver repeatability and interobserver reproducibility.Paired T-test and Bland-Altman were used to appraise interdevice agreement.Results:Seventy-eight eyes of 78 children were included.The CoV was≤2.12 and 1.10%,respectively,for repeatability and reproducibility.TRT and CoV were lower for central and paracentral CT measurements than for peripheral measurements.The SS-OCT device generated higher precision when acquiring CT data,whereas Scheimpflug system showed higher reliability when measuring corneal keratometry.Although the CT readings measured using SS-OCT were significantly thinner than Scheimpflug device(P<0.001),the central and thinnest CT values were still of high agreement.The interdevice agreement of keratometry measurement was high for the central corneal region and moderate for the paracentral and peripheral areas.Conclusions:The precision of CT measurements by SS-OCT was higher,while the reliability of keratometry measurements by the Scheimpflug system was higher in children.Apart from the measured values in the central corneal region,the thickness and keratometry readings should not be considered interchangeable between the two systems.