We present and discuss deep high resolution images taken with the ESO NTT as well as spectra taken with the ESO VLT in the field of the BL Lac object PKS 0537 441. We could neither detect the host galaxy nor a galaxy ...We present and discuss deep high resolution images taken with the ESO NTT as well as spectra taken with the ESO VLT in the field of the BL Lac object PKS 0537 441. We could neither detect the host galaxy nor a galaxy along the line of sight to the BL Lac as claimed from previous observations. We found 4 nearby companion galaxies which could be a splitted and magnified image of a distant background galaxy. Our VLT spectra, however, rule out this possibility. All 4 companions have similar redshifts as the BL Lac and may (at least in part) trigger the enormous activity in this source. PKS 0537 441 might be located in a galaxy cluster as rich as Abell 1. Alternatively, the BL Lac could also be located in the outskirts of a galaxy cluster or even be projected on a large scale structure as indicated by spectra of 30 galaxies in the field. Either lensing hypothesis (lens or being lensed) is considerably weakened by our observations.展开更多
From 2011 to 2021,LAMOST has released a total of 76,167 quasar data.We try to search for gravitationally lensed QSOs by limiting coordinate differences and redshift differences of these QSOs.The name,brightness,spectr...From 2011 to 2021,LAMOST has released a total of 76,167 quasar data.We try to search for gravitationally lensed QSOs by limiting coordinate differences and redshift differences of these QSOs.The name,brightness,spectrum,photometry and other information of each QSO will be visually checked carefully.Special attention should be paid to check whether there are groups of galaxies,gravitationally lensed arcs,Einstein crosses,or Einstein rings near the QSOs.Through careful selection,we select LAMOST J160603.01+290050.8(A)and LAMOST J160602.81+290048.7(B)as a candidate and perform an initial analysis.Components A and B are336 apart and they display blue during photometric observations.The redshift values of components A and B are0.2%different,their Gaia_g values are 1.3%different,and their ugriz values are 1.0%or less different.For the spectra covering from 3690 to 9100?,the emission lines of C II,Mg,Hγ,OⅢ,and Hβare present for both components A and B and the ratio of flux(B)to flux(A)from LAMOST is basically a constant,around 2.2.However,no galaxies have been found between components A and B.Inada et al.identified them as binary quasars.But we accidentally find a galaxy group near components A and B.If the center of dark matter in the galaxy group is at the center between components A and B,components A and B are probably gravitationally lensed QSOs.We estimate that the Einstein mass is 1.46×10^(11)M_⊙and the total mass of the lens is1.34×10^(13)M_⊙.The deflection angle is 197 at positions A and B and the velocity dispersion is 261 km s^(-1).Theoretically,this candidate could be a pair of fold images of a strong lensing system by a galaxy group,and we will investigate the possibility when the redshifts of nearby galaxies are available.展开更多
After a brief reminder of the mechanism of gravitational lensing of ex- tended sources, the particular case of the host galaxy of QSO RXJ0911, a high red-shift （z - 2.8） quadruply imaged quasar, is explored. The non...After a brief reminder of the mechanism of gravitational lensing of ex- tended sources, the particular case of the host galaxy of QSO RXJ0911, a high red-shift （z - 2.8） quadruply imaged quasar, is explored. The non linearity of the problem, together with the proximity of the source to a cusp of the lens inner caustic, has impor-tant consequences on the dependence of the image appearance on the size and shape of the source. Their expected main features and their interpretation in terms of source extension and shape are investigated in a spirit of simplicity and in preparation for the analysis of high sensitivity and spatial resolution images that will soon be within reach with the completion of the Atacama Large Millimeter/submillimeter Array （ALMA）. In particular, the information on source size carded by relative image brightness is dis-cussed. Extension of the results to other types of quadruply imaged quasars is briefly considered.展开更多
We study the statistics of large-separation multiply-imaged quasars lensed by clusters of galaxies. In particular, we examine how the observed brightest cluster galaxies （BCGs） affect the predicted numbers of wide-s...We study the statistics of large-separation multiply-imaged quasars lensed by clusters of galaxies. In particular, we examine how the observed brightest cluster galaxies （BCGs） affect the predicted numbers of wide-separation lenses. We model the lens as an NFW-profiled dark matter halo with a truncated singular isothermal sphere to represent the BCG in its center. We mainly make predictions for the Sloan Digital Sky Survey Quasar Lens Search （SQLS） sample from the Data Release 5 （DRS） in two standard ACDM cosmological models： a model with matter density ΩM = 0.3 and δ8 = 0.9, as is usually adopted in the literature （ACDM1）, and a model suggested by the WMAP seven-year （WMAPT） data with ΩM = 0.266 and δ8 = 0.801. We also study the lensing properties for the WMAP3 cosmology in order to compare with the previous work. We find that BCGs in the centers of clusters significantly enhance the lensing efficiency by a factor of 2 - 3 compared with that of NFW-profiled pure dark matter halos. In addition, the dependence of mass ratios of BCGs to their host halos on the host halo masses reduces the lensing rate by - 20% from assuming a constant ratio as in previous studies, but considering the evolution of this ratio with redshift out to z - 1 would reduce it by - 3%. Moreover, we predict that the numbers of lensed quasars with image separations larger than 10″ in the statistical sample of SQLS from DR5 are 1.22 and 0.47, respectively for ACDM1 and WMAP7 and 0.73 and 0.33 for separations between 10″ and 20″, which are consistent with the only observed cluster lens with such a large separation in the complete SQLS sample.展开更多
Strong lensing time delay measurement is a promising method to address the Hubble tension,offering a completely independent approach compared with both the cosmic microwave background analysis and the local distance l...Strong lensing time delay measurement is a promising method to address the Hubble tension,offering a completely independent approach compared with both the cosmic microwave background analysis and the local distance ladder.As a third-party examination of the Hubble tension,this method provides a unique perspective.Strongly lensed quasar(gl QSO)systems have demonstrated significant potential in tackling this issue,achieving an impressive 2%accuracy level.However,advancing to 1%or sub-percent accuracy is challenging due to several intrinsic limitations of gl QSOs.Fortunately,strongly lensed supernovae(gl SNe)offer a more robust solution,thanks to their characteristic light curve,significant brightness variations,and additional advantages.The Muztagh-Ata 1.93 m Synergy Telescope(MOST)is an exceptional instrument for monitoring strong lensing time delays.In this study,we simulate the follow-up multi-band light curve monitoring for gl SNe Ia systems,which are expected to be firstly discovered by the Chinese Survey Space Telescope(CSST).The simulation employs the W7 model,integrating strong lensing and microlensing effects.Our results show that with 300 s×9 exposures in each epoch,2 quadruple-image systems and14 double-image systems are observable by MOST each year.MOST can achieve a signal-to-noise ratio(SNR)of approximately 50 for the brightest images of gl SNe Ia,while even the faintest images maintain an SNR of at least 7.Using a standard SNe Ia light curve template for fitting,we measured the time delays.With a 2-d cadence,MOST achieves a relative time delay error of less than 4.9%,with the bias typically remaining below 0.57%.Finally,we performed a Hubble parameter estimation.For a typical gl SNe Ia system,the H0error is about±1.8 km s^(-1)Mpc^(-1).This result is comparable or even better than those from LSST.This study highlights the capability of MOST to significantly advance the precision of time delay measurements,offering a promising path toward resolving the Hubble tension.展开更多
The Macquart relation and time-delay cosmography are now two promising ways to fast radio burst(FRB)cosmology.In this work,we propose a joint method that combines strongly lensed and unlensed FRBs for improving cosmol...The Macquart relation and time-delay cosmography are now two promising ways to fast radio burst(FRB)cosmology.In this work,we propose a joint method that combines strongly lensed and unlensed FRBs for improving cosmological parameter estimation using simulated FRB data from the future sensitive coherent all-sky monitor survey,which is expected to detect a large number of FRBs including galaxy-galaxy strongly lensed events.We find that using a detectable sample of 100000 localized FRBs including 40 lensed events can simultaneously constrain the Hubble constant and the equation of state of dark energy,with high precision of ε(H_(0))=0.4% and ε(w)=4.5% in the simplest dynamical dark energy model.The joint analysis of unlensed and lensed FRBs significantly improves the constraint on H_(0),which could be more effective than combining either the unlensed FRBs with future gravitational wave(GW)standard sirens or the lensed FRBs with CMB.Furthermore,combining the full FRB sample with the CMB+BAO+SNe data yields σ(H_(0))=0.29 km s^(-1)Mpc^(-1),σ(w_(0))=0.046,and σ(w_(a))=0.15 in the two-parameter dynamical dark energy model,which outperforms the results from the CMB+BAO+SNe+GW data.This reinforces the cosmological implications of a multi-wavelength observational strategy in optical and radio bands.We conclude that the future FRB observations will shed light on the nature of dark energy and also the Hubble tension if enough events with long-duration lensing are incorporated.展开更多
The Hubble constant H0,a key parameter quantifying the present expansion rate of the universe,remains a subject of significant debate due to the persistent tension between early-and late-universe measurements.Strong g...The Hubble constant H0,a key parameter quantifying the present expansion rate of the universe,remains a subject of significant debate due to the persistent tension between early-and late-universe measurements.Strong gravitational lensing(SGL) time delays provide an independent avenue to constrain H0.In this paper,we utilize seven SGL systems from the TDCOSMO sample to constrain H_(0),employing the model-independent approaches:deep neural networks(DNN),Gaussian process(GP),polynomial fitting(polyfit) and Padé approximant(PA).Using these methods,we reconstruct unanchored luminosity distances from the Pantheon+SNe Ia dataset and obtain H_(0)=72.3_(-3.6)^(+3.8)km s^(-1)Mpc^(-1),H_(0)=72.4_(-1.7)^(+1.6)km s^(-1)Mpc^(-1),H0=70.7_(-3.1)^(+3.0)km s^(-1)Mpc^(-1)and H0=74.0_(-2.7)^(+2.7)km s^(-1)Mpc^(-1),respectively.These estimates are consistent within 1σ level and align with local distance ladder results.Notably,the GP method achieves uncertainties that are half those of the DNN approach,whereas the DNN method offers more reliable confidence intervals in reconstruction at high redshifts.Our findings underscore the potential of these methodologies to refine constraints on H_(0) and contribute to resolving the Hubble tension with future advancements.展开更多
A novel fabrication method for lensed fiber array has been proposed utilizing UV-curable fluorinated polymer, whose refractive index is matched to fused silica. The structure is composed of three segments; single mode...A novel fabrication method for lensed fiber array has been proposed utilizing UV-curable fluorinated polymer, whose refractive index is matched to fused silica. The structure is composed of three segments; single mode fiber, coreless silica fiber and UV-curable polymer lens-tip. Flexible control of the curvature of lens-tip was realized by control of deposited volume of the liquid polymer and free-space interconnection performances are characterized.展开更多
MXene-based smart contact lenses demonstrate a cutting-edge advancement in wearable ophthalmic technology,combining real-time biosensing,therapeutic capabilities,and user comfort in a single platform.These devices tak...MXene-based smart contact lenses demonstrate a cutting-edge advancement in wearable ophthalmic technology,combining real-time biosensing,therapeutic capabilities,and user comfort in a single platform.These devices take the advantage of the exceptional electrical conductivity,mechanical flexibility,and biocompatibility of two-dimensional MXenes to enable noninvasive,tear-based monitoring of key physiological markers such as intraocular pressure and glucose levels.Recent developments focus on the integration of transparent MXene films into the conventional lens materials,allowing multifunctional performance including photothermal therapy,antimicrobial and anti-inflammation protection,and dehydration resistance.These innovations offer promising strategies for ocular disease management and eye protection.In addition to their multifunctionality,improvements in MXene synthesis and device engineering have enhanced the stability,transparency,and wearability of these lenses.Despite these advances,challenges remain in long-term biostability,scalable production,and integration with wireless communication systems.This review summarizes the current progress,key challenges,and future directions of MXene-based smart contact lenses,highlighting their transformative potential in next-generation digital healthcare and ophthalmic care.展开更多
The cosmic distance relation(DDR) associates the angular diameters distance(DA) and luminosity distance(DL) by a simple formula,i.e.,DL=(1+z)2 DA.The strongly lensed gravitational waves(GWs) provide a unique way to me...The cosmic distance relation(DDR) associates the angular diameters distance(DA) and luminosity distance(DL) by a simple formula,i.e.,DL=(1+z)2 DA.The strongly lensed gravitational waves(GWs) provide a unique way to measure DA and DL simultaneously to the GW source,hence they can be used as probes to test DDR.In this study,we investigated the use of strongly lensed GW events from the future Einstein Telescope to test DDR.We assumed the possible deviation of DDR as(1+z)2 DA/DL=η(z),and considered two different parametrizations of η(z),namely,η1(z)=1+η0 z and η2(z)=1+η0 z/(1+z).Numerical simulations showed that,with about 100 strongly lensed GW events observed by ET,the parameter η0 was constrained at 1.3% and 3% levels for the first and second parametrizations,respectively.展开更多
We propose a new method to test the cosmic distance duality relation using the strongly lensed gravitational waves.The simultaneous observation of the image positions,relative time delay between different images,redsh...We propose a new method to test the cosmic distance duality relation using the strongly lensed gravitational waves.The simultaneous observation of the image positions,relative time delay between different images,redshift measurements of the lens and the source,together with the mass modelling of the lens galaxy,provide the angular diameter distance to the gravitational wave source.On the other hand,the luminosity distance to the source can be obtained from the observation of the gravitational wave signals.To our knowledge this is the first time a method is proposed to simultaneously measure the angular diameter distance and the luminosity distance from the same source.Hence,the strongly lensed gravitational waves provide a unique method to test the cosmic distance duality relation.With the construction of the third generation gravitational detectors such as the Einstein Telescope,it will be possible to test the cosmic distance duality relation with an accuracy of a few percent.展开更多
The possible variation of the electromagnetic fine structure constant, αe, at cosmological scales has aroused great interest in recent years. Strongly lensed gravitational waves（GWs） and their electromagnetic count...The possible variation of the electromagnetic fine structure constant, αe, at cosmological scales has aroused great interest in recent years. Strongly lensed gravitational waves（GWs） and their electromagnetic counterparts could be used to test this variation. Under the assumption that the speed of a photon can be modified,whereas the speed of a GW is the same as predicted by general relativity, and they both propagate in a flat FriedmanRobertson-Walker universe, we investigated the difference in time delays of the images and derived the upper bound of the variation of αe. For a typical lensing system in the standard cosmological models, we obtained B cosθ 1.85×10^（-5）,where B is the dipolar amplitude and θ is the angle between observation and the preferred direction. Our result is consistent with the most up-to-date observations on αe. In addition, the observations of strongly lensed GWs and their electromagnetic counterparts could be used to test which types of alternative theories of gravity can account for the variation of α_e.展开更多
The immune system is involved in many age-related pathological changes,also plays an important role in tissue regeneration after injury.But no immune involvement has been discussed regarding cataract since it is presu...The immune system is involved in many age-related pathological changes,also plays an important role in tissue regeneration after injury.But no immune involvement has been discussed regarding cataract since it is presumed that lens has no source of immune cells as an avascular zone.Latest research has challenged the longstanding view of the lens as an immune-privileged tissue,revealing the presence of resident immune cells and active immune responses within the lens.Thus,we summarized the immune involvement in maintaining lens homeostasis,which may be a deleterious role in the induction of lens opacification if inappropriately activated.Furthermore,bioengineer-based immunomodulatory therapies to fine-tune the micro immune environment within lens may be future strategies for in situ lens regeneration,as a novel treatment for cataract.展开更多
AIM:To compare the clinical outcomes of extended depth-of-focus intraocular lenses(EDOF IOLs)using either micromonovision implantation or mixed implantation of EDOF and diffractive bifocal IOLs.METHODS:This retrospect...AIM:To compare the clinical outcomes of extended depth-of-focus intraocular lenses(EDOF IOLs)using either micromonovision implantation or mixed implantation of EDOF and diffractive bifocal IOLs.METHODS:This retrospective clinical trial included 130 patients(260 eyes),who were divided into two groups.Group RR comprised 70 patients(140 eyes)bilaterally implanted with ZXR00 IOLs(Tecnis ZXR00,where one target was-0.5 D to-0.75 D and the other was 0 to-0.25 D).Group RM comprised 60 patients(120 eyes)unilaterally implanted with both ZXR00 and ZMB00 IOLs(Tecnis ZMB00,0 to-0.25 D).Postoperative outcomes were compared after 3 mo,including visual acuity,defocus curves,stereoacuity,modulation transfer functions(MTFs),higher-order aberrations,and Visual Function-14(VF-14)questionnaire responses.RESULTS:Group RR had superior bilateral intermediate vision,while the group RM had superior bilateral near vision(both P<0.05).Group RM also exhibited superior MTFs and reduced higher-order aberrations(both P<0.05).Stereoacuity and VF-14 questionnaire results showed no statistically significant difference between groups(P>0.05).CONCLUSION:The implantation of micromonovision has significantly improved near vision.IOLs and their collocation can be customized according to individual patient needs to achieve precise treatment and provide cataract patients with high-quality vision.展开更多
Objective To compare the efficacy of toric implantable collamer lens(Toric-ICL)and femtosecond laser-assisted in situ keratomileusis(FS-LASIK)for myopia correction in patients with moderate to high myopia complicated ...Objective To compare the efficacy of toric implantable collamer lens(Toric-ICL)and femtosecond laser-assisted in situ keratomileusis(FS-LASIK)for myopia correction in patients with moderate to high myopia complicated with astigmatism.Methods We retrospectively collected data from 64 patients(aged 18-42 years)with moderate to high myopia complicated with astigmatism(128 eyes)undergoing either Toric-ICL(28 patients/56 eyes)or FS-LASIK(36 patients/72 eyes)at our department between January,2019 and December,2020.The changes of uncorrected distance visual acuity(UCVA),spherical equivalent(SE),mean astigmatism correction index(CI),corneal endothelial cell density(ECD)and intraocular pressure(IOP)following the procedures were compared between the two groups.Results In FS-LASIK group,all the eyes(72/72)achieved an UCVA≥1.0,similar to the rate in Toric-ICL group(55/56 eyes;P=0.2374).The postoperative SE was also comparable between FS-LASIK and Toric-ICL groups[0.43±0.06 D(range:-1.0 to 1.50 D)vs 0.38±0.05 D(range:-0.75 to 1.00 D);P=0.56].The mean astigmatism CI was significantly higher in FS-LASIK group than in Toric-ICL group(0.8561 vs 0.7176;P<0.0001),and 88.89%of the eyes in FS-LASIK group and 69.64%in Toric-ICL group had postoperative astigmatism≤0.50 D.No significant changes were observed in postoperative corneal ECD in FS-LASIK group,whereas ECD decreased significantly after the procedure in Toric-ICL group(P=0.0057).The patients undergoing Toric-ICL exhibited no significant changes of postoperative IOP,but the patients receiving FS-LASIK had significantly reduced IOP after the procedure(P<0.001).Conclusion Although the patients included in Toric-ICL group had higher myopia and astigmatism,Toric-ICL still showed better predictability and efficacy for astigmatic correction in Toric-ICL group.Toric-ICL is an effective and safe equivalent of FS-LASIK for correcting moderate myopia but can be more advantageous for correcting high myopia with astigmatism.展开更多
Objective:To evaluate the performance of orthokeratology(ortho-k)lens reordering using software-designed system,so as to determine the feasibility of ortho-k lens reordering without discontinuing lens wear.Methods:Thi...Objective:To evaluate the performance of orthokeratology(ortho-k)lens reordering using software-designed system,so as to determine the feasibility of ortho-k lens reordering without discontinuing lens wear.Methods:This study is a retrospective analysis of data of ortho-k lens wearers who had a history of short-term discontinuation of lens wear.A total of 94 individuals aged over 8 years with spherical equivalent refraction ranging from-0.50 to-6.50 diopters were included.The corneal topography data at baseline(before ortho-k)and after lens wear discontinuation(cessation of ortho-k treatment)were imported separately into the lens-design software,along with corresponding refraction data.Subsequently,corneal and lens parameters were generated and compared.Intraclass correlation coefficients(ICC)were calculated,and Bland and Altman analyses were conducted.Results:All 94 children were involved in the retrospective analysis.Compared with baseline data,there was a high level of consistency between Rwo(without discontinuation)and Rwith(with discontinuation),with an ICC of 0.96(P<0.001).Furthermore,the comparison of lens parameters generated by the Easyfit software between baseline and after short-term discontinuation showed a high degree of consistency,with all of the ICC values exceeding 0.90.Similar results were obtained using the WAVE software,as both ICC values and Bland-Altman plots demonstrated a high level of consistency in lens parameters between two conditions(nearly all data points fell within the 95%LoAs).Conclusions:It is feasible to directly reorder new ortho-k lenses using software fitting approaches.However,further investigations are necessary to validate their practicability in a clinical setting.展开更多
AIM:To assess whether the implantation of a posterior chamber phakic intraocular lens produces changes in optical coherence tomography(OCT)measurements of macular thickness(MT)and two parameters that define the struct...AIM:To assess whether the implantation of a posterior chamber phakic intraocular lens produces changes in optical coherence tomography(OCT)measurements of macular thickness(MT)and two parameters that define the structure of the optic nerve,the peripapillary nerve fiber layer(RNFL)and the Bruch’s membrane opening-minimum rim width(BMO-MRW).METHODS:This nonrandomized prospective pre-post study included 86 eyes of 48 patients(age,20-47y;axial length:23.10-28.95 mm)scheduled for myopia or myopic astigmatism correction with implantation of the implantable collamer lens(ICL).Eyes with glaucoma or any other ocular disease that could alter OCT results were excluded.RNFL,BMO-MRW and MT were measured preoperatively,and at 1 and 6mo after surgery using spectral-domain OCT.Changes between preoperative and postoperative values were evaluated.RESULTS:There was a significant increase in BMOMRW at 1mo(mean change:3.48±15.07μm,P=0.041).No significant changes were found during the rest of followup(1-6mo postop.,P=0.623).There was also a significant increase in RNFL thickness at 1mo af ter surger y(1.45±2.18μm,P<0.001),but with a significant reduction from 1 to 6mo postoperatively(P=0.002).Regarding MT,it increased significantly at 1mo(2.46±3.76μm,P<0.001),with a significant decrease afterwards(P=0.048).Measurements of the three parameters at 6mo were slightly superior to preoperative values(P<0.01).CONCLUSION:Minimal changes are induced in BMOMRW,RNFL and MT after ICL implantation in healthy eyes,confirming the safety of the surgical procedure regarding the structure of the optic nerve head and the macula,and indicating that this phakic intraocular lens seems to have a slight impact on OCT measurements.展开更多
AIM:To examine how three distinct central positioning techniques for anterior capsulotomy-pupil center,limbus center,and lens apex-affect intraocular lens(IOL)placement and visual quality following femtosecond laser-a...AIM:To examine how three distinct central positioning techniques for anterior capsulotomy-pupil center,limbus center,and lens apex-affect intraocular lens(IOL)placement and visual quality following femtosecond laser-assisted cataract surgery(FLACS).METHODS:A total of 36 patients(72 eyes)with age-related cataracts who underwent FLACS and ZCB00 aspherical IOL implantation at Aier Eye Hospital Medical Center,Anhui Medical University between January and December 2023 were included in this prospective study.Patients were divided into three groups based on the central positioning mode for anterior capsulotomy:pupil center,limbus center,and lens apex center groups.IOL alignment and displacement were evaluated using the Casia2 device,and the postoperative visual quality was assessed.RESULTS:At 1 d postoperatively,the IOL tilt for the pupil,limbus,and apex groups were 3.96°±1.51°,4.63°±1.87°,and 3.90°±2.24°,respectively(F=1.07,P=0.35);IOL decentration values were 0.21±0.10 mm,0.23±0.16 mm,and 0.21±0.12 mm,respectively(F=0.14,P=0.87);total higher-order aberrations were 0.32±0.40μm,0.56±0.61μm,and 0.53±0.60μm,respectively(F=1.38,P=0.26);and coma aberrations values were 0.13±0.10μm,0.16±0.15μm,and 0.14±0.15μm,respectively(F=0.3,P=0.74).All results obtained postoperative day 1 did not differ significantly.At 3 mo postoperatively,IOL tilt values were 5.42°±2.00°,3.96°±1.44°,and 3.20°±1.19°,respectively(F=12.40,P<0.001);IOL decentration values were 0.33±0.07 mm,0.23±0.11 mm,and 0.21±0.11 mm,respectively(F=4.99,P=0.008);total higher-order aberrations were 0.67±0.29μm,0.44±0.37μm,and 0.42±0.19μm,respectively(F=5.50,P=0.006);and coma aberrations values were 0.21±0.12μm,0.19±0.12μm,and 0.12±0.11μm,respectively(F=3.87,P=0.03).All results obtained 3 mo postoperatively were statistically significant.CONCLUSION:Using the lens apex as the central positioning mode for anterior capsulotomy in FLACS improves postoperative IOL stability and reduces postoperative IOL tilt and decentration.If the lens apex cannot be determined intraoperatively,the limbus center-positioning mode is recommended.展开更多
Dear Editor,The latest Visian implantable collamer lens(ICL)with a central port design(Aquaport;model V4c)obviates the necessity for preoperative laser iridotomy or intraoperative iridectomy by allowing the free flow ...Dear Editor,The latest Visian implantable collamer lens(ICL)with a central port design(Aquaport;model V4c)obviates the necessity for preoperative laser iridotomy or intraoperative iridectomy by allowing the free flow of the aqueous humor between the sides of the intraocular lens.The design of Aquaport can also eliminate the complications associated with iridotomy and iridectomy.Therefore,the V4c ICL has the potential to significantly reduce the risk of pupillary block compared to its predecessors.展开更多
At present,the naked-eye three-dimensional(3D)display technology still has some drawbacks,such as low brightness uniformity,high crosstalk,low light efficiency,short viewing distance,and the manufacturing is difficult...At present,the naked-eye three-dimensional(3D)display technology still has some drawbacks,such as low brightness uniformity,high crosstalk,low light efficiency,short viewing distance,and the manufacturing is difficulty.Based on the principle of naked-eye 3D display and the Fresnel optical theory,this paper designs a Fresnel lens array and the star-shaped liquid crystal display(LCD)switch of unit LCD screen to achieve low-crosstalk and high brightness uniformity for the autostereoscopic 3D display.The unit parameters of a 139.7 cm 4K model autostereoscopic 3D displayer are provided and they are optimized by the TracePro software.The results show that when the pitch of the Fresnel lens on the exit surface is 0.304 mm,the width of each serration of Fresnel lens is 0.0234 mm,the length of the Fresnel lens is 2.87 mm,and the center height of star-shaped LCD switch is 0.030 mm,the center length is 0.040 mm,the width of star-shaped LCD switch is 0.050 mm,and the image crosstalk is less than 2%when the viewing distance is 2.50 m.The problem on the brightness of the image in different positions is improved.展开更多
文摘We present and discuss deep high resolution images taken with the ESO NTT as well as spectra taken with the ESO VLT in the field of the BL Lac object PKS 0537 441. We could neither detect the host galaxy nor a galaxy along the line of sight to the BL Lac as claimed from previous observations. We found 4 nearby companion galaxies which could be a splitted and magnified image of a distant background galaxy. Our VLT spectra, however, rule out this possibility. All 4 companions have similar redshifts as the BL Lac and may (at least in part) trigger the enormous activity in this source. PKS 0537 441 might be located in a galaxy cluster as rich as Abell 1. Alternatively, the BL Lac could also be located in the outskirts of a galaxy cluster or even be projected on a large scale structure as indicated by spectra of 30 galaxies in the field. Either lensing hypothesis (lens or being lensed) is considerably weakened by our observations.
基金provided by the National Development and Reform Commissionthe support of the National Natural Science Foundation of China(NSFC,11803004)+2 种基金Yunnan Province Youth Talent Project(2019182)the support by NSFC through grant No.12203011Yunnan provincial Department of Science and Technology through grant No.202101BA070001-261。
文摘From 2011 to 2021,LAMOST has released a total of 76,167 quasar data.We try to search for gravitationally lensed QSOs by limiting coordinate differences and redshift differences of these QSOs.The name,brightness,spectrum,photometry and other information of each QSO will be visually checked carefully.Special attention should be paid to check whether there are groups of galaxies,gravitationally lensed arcs,Einstein crosses,or Einstein rings near the QSOs.Through careful selection,we select LAMOST J160603.01+290050.8(A)and LAMOST J160602.81+290048.7(B)as a candidate and perform an initial analysis.Components A and B are336 apart and they display blue during photometric observations.The redshift values of components A and B are0.2%different,their Gaia_g values are 1.3%different,and their ugriz values are 1.0%or less different.For the spectra covering from 3690 to 9100?,the emission lines of C II,Mg,Hγ,OⅢ,and Hβare present for both components A and B and the ratio of flux(B)to flux(A)from LAMOST is basically a constant,around 2.2.However,no galaxies have been found between components A and B.Inada et al.identified them as binary quasars.But we accidentally find a galaxy group near components A and B.If the center of dark matter in the galaxy group is at the center between components A and B,components A and B are probably gravitationally lensed QSOs.We estimate that the Einstein mass is 1.46×10^(11)M_⊙and the total mass of the lens is1.34×10^(13)M_⊙.The deflection angle is 197 at positions A and B and the velocity dispersion is 261 km s^(-1).Theoretically,this candidate could be a pair of fold images of a strong lensing system by a galaxy group,and we will investigate the possibility when the redshifts of nearby galaxies are available.
基金support from the Institute for Nuclear Science and Technology, National Foundation for Science and Technology Development (NAFOSTED)the World Laboratory, the French CNRS, the French Embassy in Hanoi, Rencontres du Vietnam and Odon Vallet fellowships
文摘After a brief reminder of the mechanism of gravitational lensing of ex- tended sources, the particular case of the host galaxy of QSO RXJ0911, a high red-shift （z - 2.8） quadruply imaged quasar, is explored. The non linearity of the problem, together with the proximity of the source to a cusp of the lens inner caustic, has impor-tant consequences on the dependence of the image appearance on the size and shape of the source. Their expected main features and their interpretation in terms of source extension and shape are investigated in a spirit of simplicity and in preparation for the analysis of high sensitivity and spatial resolution images that will soon be within reach with the completion of the Atacama Large Millimeter/submillimeter Array （ALMA）. In particular, the information on source size carded by relative image brightness is dis-cussed. Extension of the results to other types of quadruply imaged quasars is briefly considered.
基金supported by the National Natural Science Foundation of China(Grant No. 11073023)the National Basic Research Program of China (973 ProgramGrant No.2009CB24901)
文摘We study the statistics of large-separation multiply-imaged quasars lensed by clusters of galaxies. In particular, we examine how the observed brightest cluster galaxies （BCGs） affect the predicted numbers of wide-separation lenses. We model the lens as an NFW-profiled dark matter halo with a truncated singular isothermal sphere to represent the BCG in its center. We mainly make predictions for the Sloan Digital Sky Survey Quasar Lens Search （SQLS） sample from the Data Release 5 （DRS） in two standard ACDM cosmological models： a model with matter density ΩM = 0.3 and δ8 = 0.9, as is usually adopted in the literature （ACDM1）, and a model suggested by the WMAP seven-year （WMAPT） data with ΩM = 0.266 and δ8 = 0.801. We also study the lensing properties for the WMAP3 cosmology in order to compare with the previous work. We find that BCGs in the centers of clusters significantly enhance the lensing efficiency by a factor of 2 - 3 compared with that of NFW-profiled pure dark matter halos. In addition, the dependence of mass ratios of BCGs to their host halos on the host halo masses reduces the lensing rate by - 20% from assuming a constant ratio as in previous studies, but considering the evolution of this ratio with redshift out to z - 1 would reduce it by - 3%. Moreover, we predict that the numbers of lensed quasars with image separations larger than 10″ in the statistical sample of SQLS from DR5 are 1.22 and 0.47, respectively for ACDM1 and WMAP7 and 0.73 and 0.33 for separations between 10″ and 20″, which are consistent with the only observed cluster lens with such a large separation in the complete SQLS sample.
基金supported by the National Natural Science Foundation of China(Grant Nos.12333001,61234003,61434004,and 61504141)the CAS Interdisciplinary Project(Grant No.KJZD-EW-L11-04)+1 种基金support from the China Postdoctoral Science Foundation(Grant No.GZC20232990)the National Natural Science Foundation of China(Grant No.12403104)。
文摘Strong lensing time delay measurement is a promising method to address the Hubble tension,offering a completely independent approach compared with both the cosmic microwave background analysis and the local distance ladder.As a third-party examination of the Hubble tension,this method provides a unique perspective.Strongly lensed quasar(gl QSO)systems have demonstrated significant potential in tackling this issue,achieving an impressive 2%accuracy level.However,advancing to 1%or sub-percent accuracy is challenging due to several intrinsic limitations of gl QSOs.Fortunately,strongly lensed supernovae(gl SNe)offer a more robust solution,thanks to their characteristic light curve,significant brightness variations,and additional advantages.The Muztagh-Ata 1.93 m Synergy Telescope(MOST)is an exceptional instrument for monitoring strong lensing time delays.In this study,we simulate the follow-up multi-band light curve monitoring for gl SNe Ia systems,which are expected to be firstly discovered by the Chinese Survey Space Telescope(CSST).The simulation employs the W7 model,integrating strong lensing and microlensing effects.Our results show that with 300 s×9 exposures in each epoch,2 quadruple-image systems and14 double-image systems are observable by MOST each year.MOST can achieve a signal-to-noise ratio(SNR)of approximately 50 for the brightest images of gl SNe Ia,while even the faintest images maintain an SNR of at least 7.Using a standard SNe Ia light curve template for fitting,we measured the time delays.With a 2-d cadence,MOST achieves a relative time delay error of less than 4.9%,with the bias typically remaining below 0.57%.Finally,we performed a Hubble parameter estimation.For a typical gl SNe Ia system,the H0error is about±1.8 km s^(-1)Mpc^(-1).This result is comparable or even better than those from LSST.This study highlights the capability of MOST to significantly advance the precision of time delay measurements,offering a promising path toward resolving the Hubble tension.
基金supported by the National SKA Program of China(Grant Nos.2022SKA0110200,and 2022SKA0110203)the National Natural Science Foundation of China(Grant Nos.12473001,11975072,11835009,and 11875102)the National 111 Project(Grant No.B16009)。
文摘The Macquart relation and time-delay cosmography are now two promising ways to fast radio burst(FRB)cosmology.In this work,we propose a joint method that combines strongly lensed and unlensed FRBs for improving cosmological parameter estimation using simulated FRB data from the future sensitive coherent all-sky monitor survey,which is expected to detect a large number of FRBs including galaxy-galaxy strongly lensed events.We find that using a detectable sample of 100000 localized FRBs including 40 lensed events can simultaneously constrain the Hubble constant and the equation of state of dark energy,with high precision of ε(H_(0))=0.4% and ε(w)=4.5% in the simplest dynamical dark energy model.The joint analysis of unlensed and lensed FRBs significantly improves the constraint on H_(0),which could be more effective than combining either the unlensed FRBs with future gravitational wave(GW)standard sirens or the lensed FRBs with CMB.Furthermore,combining the full FRB sample with the CMB+BAO+SNe data yields σ(H_(0))=0.29 km s^(-1)Mpc^(-1),σ(w_(0))=0.046,and σ(w_(a))=0.15 in the two-parameter dynamical dark energy model,which outperforms the results from the CMB+BAO+SNe+GW data.This reinforces the cosmological implications of a multi-wavelength observational strategy in optical and radio bands.We conclude that the future FRB observations will shed light on the nature of dark energy and also the Hubble tension if enough events with long-duration lensing are incorporated.
文摘The Hubble constant H0,a key parameter quantifying the present expansion rate of the universe,remains a subject of significant debate due to the persistent tension between early-and late-universe measurements.Strong gravitational lensing(SGL) time delays provide an independent avenue to constrain H0.In this paper,we utilize seven SGL systems from the TDCOSMO sample to constrain H_(0),employing the model-independent approaches:deep neural networks(DNN),Gaussian process(GP),polynomial fitting(polyfit) and Padé approximant(PA).Using these methods,we reconstruct unanchored luminosity distances from the Pantheon+SNe Ia dataset and obtain H_(0)=72.3_(-3.6)^(+3.8)km s^(-1)Mpc^(-1),H_(0)=72.4_(-1.7)^(+1.6)km s^(-1)Mpc^(-1),H0=70.7_(-3.1)^(+3.0)km s^(-1)Mpc^(-1)and H0=74.0_(-2.7)^(+2.7)km s^(-1)Mpc^(-1),respectively.These estimates are consistent within 1σ level and align with local distance ladder results.Notably,the GP method achieves uncertainties that are half those of the DNN approach,whereas the DNN method offers more reliable confidence intervals in reconstruction at high redshifts.Our findings underscore the potential of these methodologies to refine constraints on H_(0) and contribute to resolving the Hubble tension with future advancements.
文摘A novel fabrication method for lensed fiber array has been proposed utilizing UV-curable fluorinated polymer, whose refractive index is matched to fused silica. The structure is composed of three segments; single mode fiber, coreless silica fiber and UV-curable polymer lens-tip. Flexible control of the curvature of lens-tip was realized by control of deposited volume of the liquid polymer and free-space interconnection performances are characterized.
文摘MXene-based smart contact lenses demonstrate a cutting-edge advancement in wearable ophthalmic technology,combining real-time biosensing,therapeutic capabilities,and user comfort in a single platform.These devices take the advantage of the exceptional electrical conductivity,mechanical flexibility,and biocompatibility of two-dimensional MXenes to enable noninvasive,tear-based monitoring of key physiological markers such as intraocular pressure and glucose levels.Recent developments focus on the integration of transparent MXene films into the conventional lens materials,allowing multifunctional performance including photothermal therapy,antimicrobial and anti-inflammation protection,and dehydration resistance.These innovations offer promising strategies for ocular disease management and eye protection.In addition to their multifunctionality,improvements in MXene synthesis and device engineering have enhanced the stability,transparency,and wearability of these lenses.Despite these advances,challenges remain in long-term biostability,scalable production,and integration with wireless communication systems.This review summarizes the current progress,key challenges,and future directions of MXene-based smart contact lenses,highlighting their transformative potential in next-generation digital healthcare and ophthalmic care.
基金Supported by the National Natural Science Fund of China(11603005,11775038,11947406)。
文摘The cosmic distance relation(DDR) associates the angular diameters distance(DA) and luminosity distance(DL) by a simple formula,i.e.,DL=(1+z)2 DA.The strongly lensed gravitational waves(GWs) provide a unique way to measure DA and DL simultaneously to the GW source,hence they can be used as probes to test DDR.In this study,we investigated the use of strongly lensed GW events from the future Einstein Telescope to test DDR.We assumed the possible deviation of DDR as(1+z)2 DA/DL=η(z),and considered two different parametrizations of η(z),namely,η1(z)=1+η0 z and η2(z)=1+η0 z/(1+z).Numerical simulations showed that,with about 100 strongly lensed GW events observed by ET,the parameter η0 was constrained at 1.3% and 3% levels for the first and second parametrizations,respectively.
基金Supported by the National Natural Science Fund of China(11603005 and 11775038)。
文摘We propose a new method to test the cosmic distance duality relation using the strongly lensed gravitational waves.The simultaneous observation of the image positions,relative time delay between different images,redshift measurements of the lens and the source,together with the mass modelling of the lens galaxy,provide the angular diameter distance to the gravitational wave source.On the other hand,the luminosity distance to the source can be obtained from the observation of the gravitational wave signals.To our knowledge this is the first time a method is proposed to simultaneously measure the angular diameter distance and the luminosity distance from the same source.Hence,the strongly lensed gravitational waves provide a unique method to test the cosmic distance duality relation.With the construction of the third generation gravitational detectors such as the Einstein Telescope,it will be possible to test the cosmic distance duality relation with an accuracy of a few percent.
基金Supported by the National Natural Science Fund of China(11775038,11603005,11647307)
文摘The possible variation of the electromagnetic fine structure constant, αe, at cosmological scales has aroused great interest in recent years. Strongly lensed gravitational waves（GWs） and their electromagnetic counterparts could be used to test this variation. Under the assumption that the speed of a photon can be modified,whereas the speed of a GW is the same as predicted by general relativity, and they both propagate in a flat FriedmanRobertson-Walker universe, we investigated the difference in time delays of the images and derived the upper bound of the variation of αe. For a typical lensing system in the standard cosmological models, we obtained B cosθ 1.85×10^（-5）,where B is the dipolar amplitude and θ is the angle between observation and the preferred direction. Our result is consistent with the most up-to-date observations on αe. In addition, the observations of strongly lensed GWs and their electromagnetic counterparts could be used to test which types of alternative theories of gravity can account for the variation of α_e.
基金Supported by the National Natural Science Foundation of China(No.82271063No.82471054)Central Guidance for Local Scientific and Technological Development Funding Projects(No.2024ZY01057).
文摘The immune system is involved in many age-related pathological changes,also plays an important role in tissue regeneration after injury.But no immune involvement has been discussed regarding cataract since it is presumed that lens has no source of immune cells as an avascular zone.Latest research has challenged the longstanding view of the lens as an immune-privileged tissue,revealing the presence of resident immune cells and active immune responses within the lens.Thus,we summarized the immune involvement in maintaining lens homeostasis,which may be a deleterious role in the induction of lens opacification if inappropriately activated.Furthermore,bioengineer-based immunomodulatory therapies to fine-tune the micro immune environment within lens may be future strategies for in situ lens regeneration,as a novel treatment for cataract.
文摘AIM:To compare the clinical outcomes of extended depth-of-focus intraocular lenses(EDOF IOLs)using either micromonovision implantation or mixed implantation of EDOF and diffractive bifocal IOLs.METHODS:This retrospective clinical trial included 130 patients(260 eyes),who were divided into two groups.Group RR comprised 70 patients(140 eyes)bilaterally implanted with ZXR00 IOLs(Tecnis ZXR00,where one target was-0.5 D to-0.75 D and the other was 0 to-0.25 D).Group RM comprised 60 patients(120 eyes)unilaterally implanted with both ZXR00 and ZMB00 IOLs(Tecnis ZMB00,0 to-0.25 D).Postoperative outcomes were compared after 3 mo,including visual acuity,defocus curves,stereoacuity,modulation transfer functions(MTFs),higher-order aberrations,and Visual Function-14(VF-14)questionnaire responses.RESULTS:Group RR had superior bilateral intermediate vision,while the group RM had superior bilateral near vision(both P<0.05).Group RM also exhibited superior MTFs and reduced higher-order aberrations(both P<0.05).Stereoacuity and VF-14 questionnaire results showed no statistically significant difference between groups(P>0.05).CONCLUSION:The implantation of micromonovision has significantly improved near vision.IOLs and their collocation can be customized according to individual patient needs to achieve precise treatment and provide cataract patients with high-quality vision.
文摘Objective To compare the efficacy of toric implantable collamer lens(Toric-ICL)and femtosecond laser-assisted in situ keratomileusis(FS-LASIK)for myopia correction in patients with moderate to high myopia complicated with astigmatism.Methods We retrospectively collected data from 64 patients(aged 18-42 years)with moderate to high myopia complicated with astigmatism(128 eyes)undergoing either Toric-ICL(28 patients/56 eyes)or FS-LASIK(36 patients/72 eyes)at our department between January,2019 and December,2020.The changes of uncorrected distance visual acuity(UCVA),spherical equivalent(SE),mean astigmatism correction index(CI),corneal endothelial cell density(ECD)and intraocular pressure(IOP)following the procedures were compared between the two groups.Results In FS-LASIK group,all the eyes(72/72)achieved an UCVA≥1.0,similar to the rate in Toric-ICL group(55/56 eyes;P=0.2374).The postoperative SE was also comparable between FS-LASIK and Toric-ICL groups[0.43±0.06 D(range:-1.0 to 1.50 D)vs 0.38±0.05 D(range:-0.75 to 1.00 D);P=0.56].The mean astigmatism CI was significantly higher in FS-LASIK group than in Toric-ICL group(0.8561 vs 0.7176;P<0.0001),and 88.89%of the eyes in FS-LASIK group and 69.64%in Toric-ICL group had postoperative astigmatism≤0.50 D.No significant changes were observed in postoperative corneal ECD in FS-LASIK group,whereas ECD decreased significantly after the procedure in Toric-ICL group(P=0.0057).The patients undergoing Toric-ICL exhibited no significant changes of postoperative IOP,but the patients receiving FS-LASIK had significantly reduced IOP after the procedure(P<0.001).Conclusion Although the patients included in Toric-ICL group had higher myopia and astigmatism,Toric-ICL still showed better predictability and efficacy for astigmatic correction in Toric-ICL group.Toric-ICL is an effective and safe equivalent of FS-LASIK for correcting moderate myopia but can be more advantageous for correcting high myopia with astigmatism.
基金supported by the National Natural Science Foundation of China(82371089).
文摘Objective:To evaluate the performance of orthokeratology(ortho-k)lens reordering using software-designed system,so as to determine the feasibility of ortho-k lens reordering without discontinuing lens wear.Methods:This study is a retrospective analysis of data of ortho-k lens wearers who had a history of short-term discontinuation of lens wear.A total of 94 individuals aged over 8 years with spherical equivalent refraction ranging from-0.50 to-6.50 diopters were included.The corneal topography data at baseline(before ortho-k)and after lens wear discontinuation(cessation of ortho-k treatment)were imported separately into the lens-design software,along with corresponding refraction data.Subsequently,corneal and lens parameters were generated and compared.Intraclass correlation coefficients(ICC)were calculated,and Bland and Altman analyses were conducted.Results:All 94 children were involved in the retrospective analysis.Compared with baseline data,there was a high level of consistency between Rwo(without discontinuation)and Rwith(with discontinuation),with an ICC of 0.96(P<0.001).Furthermore,the comparison of lens parameters generated by the Easyfit software between baseline and after short-term discontinuation showed a high degree of consistency,with all of the ICC values exceeding 0.90.Similar results were obtained using the WAVE software,as both ICC values and Bland-Altman plots demonstrated a high level of consistency in lens parameters between two conditions(nearly all data points fell within the 95%LoAs).Conclusions:It is feasible to directly reorder new ortho-k lenses using software fitting approaches.However,further investigations are necessary to validate their practicability in a clinical setting.
文摘AIM:To assess whether the implantation of a posterior chamber phakic intraocular lens produces changes in optical coherence tomography(OCT)measurements of macular thickness(MT)and two parameters that define the structure of the optic nerve,the peripapillary nerve fiber layer(RNFL)and the Bruch’s membrane opening-minimum rim width(BMO-MRW).METHODS:This nonrandomized prospective pre-post study included 86 eyes of 48 patients(age,20-47y;axial length:23.10-28.95 mm)scheduled for myopia or myopic astigmatism correction with implantation of the implantable collamer lens(ICL).Eyes with glaucoma or any other ocular disease that could alter OCT results were excluded.RNFL,BMO-MRW and MT were measured preoperatively,and at 1 and 6mo after surgery using spectral-domain OCT.Changes between preoperative and postoperative values were evaluated.RESULTS:There was a significant increase in BMOMRW at 1mo(mean change:3.48±15.07μm,P=0.041).No significant changes were found during the rest of followup(1-6mo postop.,P=0.623).There was also a significant increase in RNFL thickness at 1mo af ter surger y(1.45±2.18μm,P<0.001),but with a significant reduction from 1 to 6mo postoperatively(P=0.002).Regarding MT,it increased significantly at 1mo(2.46±3.76μm,P<0.001),with a significant decrease afterwards(P=0.048).Measurements of the three parameters at 6mo were slightly superior to preoperative values(P<0.01).CONCLUSION:Minimal changes are induced in BMOMRW,RNFL and MT after ICL implantation in healthy eyes,confirming the safety of the surgical procedure regarding the structure of the optic nerve head and the macula,and indicating that this phakic intraocular lens seems to have a slight impact on OCT measurements.
文摘AIM:To examine how three distinct central positioning techniques for anterior capsulotomy-pupil center,limbus center,and lens apex-affect intraocular lens(IOL)placement and visual quality following femtosecond laser-assisted cataract surgery(FLACS).METHODS:A total of 36 patients(72 eyes)with age-related cataracts who underwent FLACS and ZCB00 aspherical IOL implantation at Aier Eye Hospital Medical Center,Anhui Medical University between January and December 2023 were included in this prospective study.Patients were divided into three groups based on the central positioning mode for anterior capsulotomy:pupil center,limbus center,and lens apex center groups.IOL alignment and displacement were evaluated using the Casia2 device,and the postoperative visual quality was assessed.RESULTS:At 1 d postoperatively,the IOL tilt for the pupil,limbus,and apex groups were 3.96°±1.51°,4.63°±1.87°,and 3.90°±2.24°,respectively(F=1.07,P=0.35);IOL decentration values were 0.21±0.10 mm,0.23±0.16 mm,and 0.21±0.12 mm,respectively(F=0.14,P=0.87);total higher-order aberrations were 0.32±0.40μm,0.56±0.61μm,and 0.53±0.60μm,respectively(F=1.38,P=0.26);and coma aberrations values were 0.13±0.10μm,0.16±0.15μm,and 0.14±0.15μm,respectively(F=0.3,P=0.74).All results obtained postoperative day 1 did not differ significantly.At 3 mo postoperatively,IOL tilt values were 5.42°±2.00°,3.96°±1.44°,and 3.20°±1.19°,respectively(F=12.40,P<0.001);IOL decentration values were 0.33±0.07 mm,0.23±0.11 mm,and 0.21±0.11 mm,respectively(F=4.99,P=0.008);total higher-order aberrations were 0.67±0.29μm,0.44±0.37μm,and 0.42±0.19μm,respectively(F=5.50,P=0.006);and coma aberrations values were 0.21±0.12μm,0.19±0.12μm,and 0.12±0.11μm,respectively(F=3.87,P=0.03).All results obtained 3 mo postoperatively were statistically significant.CONCLUSION:Using the lens apex as the central positioning mode for anterior capsulotomy in FLACS improves postoperative IOL stability and reduces postoperative IOL tilt and decentration.If the lens apex cannot be determined intraoperatively,the limbus center-positioning mode is recommended.
基金Supported by the National Key Research and Development Program(No.2019YFC1710200)the Shandong Province Pharmaceutical Technology Development Project(No.202107020970).
文摘Dear Editor,The latest Visian implantable collamer lens(ICL)with a central port design(Aquaport;model V4c)obviates the necessity for preoperative laser iridotomy or intraoperative iridectomy by allowing the free flow of the aqueous humor between the sides of the intraocular lens.The design of Aquaport can also eliminate the complications associated with iridotomy and iridectomy.Therefore,the V4c ICL has the potential to significantly reduce the risk of pupillary block compared to its predecessors.
基金supported by the 2022 Fujian Provincial Young and Middle-aged Teacher Education and Research Project(Science and Technology)(No.JAT220468)the Xiamen Natural Science Foundation(No.3502Z20227334).
文摘At present,the naked-eye three-dimensional(3D)display technology still has some drawbacks,such as low brightness uniformity,high crosstalk,low light efficiency,short viewing distance,and the manufacturing is difficulty.Based on the principle of naked-eye 3D display and the Fresnel optical theory,this paper designs a Fresnel lens array and the star-shaped liquid crystal display(LCD)switch of unit LCD screen to achieve low-crosstalk and high brightness uniformity for the autostereoscopic 3D display.The unit parameters of a 139.7 cm 4K model autostereoscopic 3D displayer are provided and they are optimized by the TracePro software.The results show that when the pitch of the Fresnel lens on the exit surface is 0.304 mm,the width of each serration of Fresnel lens is 0.0234 mm,the length of the Fresnel lens is 2.87 mm,and the center height of star-shaped LCD switch is 0.030 mm,the center length is 0.040 mm,the width of star-shaped LCD switch is 0.050 mm,and the image crosstalk is less than 2%when the viewing distance is 2.50 m.The problem on the brightness of the image in different positions is improved.
