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Evaluation of visual quality of spherical and aspherical intraocular lenses by Optical Quality Analysis System 被引量:11
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作者 Yan Chen Xue Wang +1 位作者 Chuan-Di Zhou Qiang Wu 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2017年第6期914-918,共5页
AIM: To evaluate the impact of spherical and aspherical intraocular lenses on the postoperative visual quality of age-related cataract patients using Optical Quality Analysis System (OQAS). METHODS: Seventy-four ... AIM: To evaluate the impact of spherical and aspherical intraocular lenses on the postoperative visual quality of age-related cataract patients using Optical Quality Analysis System (OQAS). METHODS: Seventy-four eyes with age-related cataracts were randomly divided into spherical and aspherical lens implantation groups. Best-corrected visual acuity (BCVA) was measured preoperatively, one day, one week, two weeks, one month and two months after surgery. A biometric systems analysis using the OQAS objective scattering index (OSI) was performed. RESULTS: There were no significant differences in visual acuity (P〉0.05) before and after spherical and aspheric lens implantation. There was a negative linear correction between the OSI value and BCVA (t-=-0.634, P=-0.000), and positive corrections between the OSI value and the lens LOCUS III value of nucleus color (NC), nucleus opacity (NO), cortex (C) and posterior lens capsular (P) (r=0.704, P=0.000; r=0.514, P=0.000; r=0.276, P=0.020; r=0.417, P=-0.000, respectively). OSI values of spherical vs aspherical lenses were 11.5±3.6 vs 11.8±3.4, 4.1±0.9 vs 3.3±0.8, 3.5±0.9 vs 2.7±0.7, 3.3±0.8 vs 2.6±0.7, 3.2±0.7 vs 2.5±0.8, and 3.2±0.8 vs 2.50.8 before and ld, 1, 2wk, 1 and 2mo after surgery, respectively. All time points varied significantly (P〈0.01) between the two groups. CONCLUSION: Aspherical IOLs does not significantly affect visual acuity compared with spherical IOLs. The OSI value, was significantly lower in the aspherical lens group compared with the spherical lens. This study shows that objective visual quality of aspheric IOLs is better than that of the spherical lens by means of OQAS biological measurement method. 展开更多
关键词 optical quality analysis system age-relatedcataract spherical lens aspherical lens objective scatteringindex
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Visual and optical performance of eyes with different corneal spherical aberration implanted with aspheric intraocular lens 被引量:8
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作者 Xian-Hui Gong Qin-Xiang Zheng +4 位作者 Na Wang Ding Chen Juan Zhao Jin Li and Yun-E Zhao 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2012年第3期323-328,共6页
AIM: To compare the visual and optical performance of eyes with different corneal spherical aberration (SA) implanted with spherical aberration-free intraocular lens (IOLs). METHODS: Thirty-six patients with different... AIM: To compare the visual and optical performance of eyes with different corneal spherical aberration (SA) implanted with spherical aberration-free intraocular lens (IOLs). METHODS: Thirty-six patients with different corneal SA had phacoemulsification with implantation of spherical aberration-free IOLs. Patients were divided into 3 groups according to the value of preoperative corneal SA. Eyes with corneal SA <0.10 mu m were assigned to group A, those with 0.10 <= corneal SA <0.20 mu m to Group B, and those with 0.20 <= corneal SA <0.35 mu m to Group C. Best-corrected visual acuity (BCVA), contrast sensitivity, corneal SA, total ocular aberrations, and depth of focus were recorded 3 months postoperatively. Distance-corrected near and intermediate visual acuity was studied to measure depth of focus. RESULTS: BCVA and contrast sensitivity were similar between groups. There were no significant differences in distance-corrected near or intermediate visual acuity. Corneal SA was similar before and 3 months after surgery in the 3 groups. With a 5.0mm pupil diameter, root mean square values for total ocular higher-order aberrations (HOAs) were lower in groups A and B than in group C. Total ocular SA was lower in group A than in groups B and C. SA was also lower in group B than in group C. Coma and trefoil were similar between the groups. CONCLUSION: Implantation of spherical aberration-free IOLs in eyes with different corneal SA results in similar visual performance at BCVA, contrast sensitivity and depth of focus. 展开更多
关键词 spherical aberration-free intraocular lens sherical aberration contrast sensitivity CATARACT
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Visual function and higher order aberration after implantation of aspheric and spherical multifocal intraocular lenses:a meta-analysis 被引量:6
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作者 Jian-Ping Liu Fan Zhang +2 位作者 Jiang-Yue Zhao Li-Wei Ma Jin-Song Zhang 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2013年第5期690-695,共6页
AIMTo assess the visual outcomes of aspheric multifocal intraocular lenses (IOLs) compared with spherical multifocal IOL after cataract surgery.
关键词 aspheric multifocal intraocular lens uncorrected near visual acuity uncorrected distance visual acuity spherical multifocal intraocular lens higher order aberration META-ANALYSIS
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Does offering only the spherical contact lens trial to the low astigmats mislead the practitioners?
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作者 Monica Chaudhry Surendra Prasad Sah +1 位作者 Indra Prasad Sharma Soujanya Mondal 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2021年第8期1281-1284,共4页
AIM:To compare the visual acuity(VA),comfort,and patient preference in a soft toric contact lens(TCL)versus soft spherical contact lens(SCL)in low astigmatic subjects during the contact lens(CL)trial.METHODS:This subj... AIM:To compare the visual acuity(VA),comfort,and patient preference in a soft toric contact lens(TCL)versus soft spherical contact lens(SCL)in low astigmatic subjects during the contact lens(CL)trial.METHODS:This subject-masked,block randomized,2×2 crossover study recruited 40 neophyte subjects(80 eyes)aged 18 to 33 y with astigmatism in the range of 0.75-1.25 D with or without spherical power from-6.00 D to+6.00 D.The participants were scheduled for two days CL trial and were fitted with the best-fit SCL and TCL.After 4 h of wear,they were assessed objectively for high contrast VA and subjective vision,comfort,and preference.RESULTS:The responses of 36 subjects(response rate 90%)with a mean age of 23.02±2.97 y(range 18 to 33 y)were analyzed.One-line improvement of monocular VA in the logMAR chart was reported to TCL as compared to SCL(-0.044±0.06 vs 0.04±0.03 logMAR,P=0.01)but the binocular vision remained similar(-0.12±0.07 vs-0.14±0.04 logMAR,P=0.38).Subjects felt a noticeable difference in clarity when shifted to TCL as compared to the SCL.The satisfaction with vision(vision quality)was significantly better with TCL(P=0.03).The fatigue with TCL was graded less at 2.5±0.6,compared to SCL at 4.6±1.3(P=0.04).Thirty-three participants(91.6%)preferred to use contact lens of which 26 participants(79%)preferred TCL.CONCLUSION:The findings suggest that VA and comfort are better with TCL as compared to SCL which is only observed if the patient was offered both offering SCL with spherical equivalent power alone as the first option can mislead the practitioner;TCL trial should be the first choice of the lens in low-to-moderate astigmatism. 展开更多
关键词 ASTIGMATISM COMFORT spherical contact lens toric contact lens visual acuity
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Spherically Symmetric Wormhole Gravitational Lens Deflection Angle Signifying Braneworld Cosmology
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作者 Anuar Alias Wan Ahmad Tajuddin Wan Abdullah 《Chinese Physics Letters》 SCIE CAS CSCD 2017年第6期19-23,共5页
Previously, the gravitational lens of a wormhole was introduced by various researchers. Their treatment was focused basically on the lens signature that describes wormhole geometrical character such as the differences... Previously, the gravitational lens of a wormhole was introduced by various researchers. Their treatment was focused basically on the lens signature that describes wormhole geometrical character such as the differences from a black hole or between any various types of wormhole models. The braneworld scenario provides the idea of spacetime with underlying extra-dimensions. The inclusion of extra-dimensional terms in the lens object spacetime line element will result in some variation in the expression for its gravitational lens deflection angle. Thus in this paper we investigate such variation by deriving this deflection angle expression. As such, this paper not only shows the existence of such variation but also suggests the potential utilization of gravitational lensing to prove the existence of extra dimensions by studying the deflection angle characteristic in accordance with the spacetime expansion rate of the universe. 展开更多
关键词 spherically Symmetric Wormhole Gravitational lens Deflection Angle Signifying Braneworld Cosmology
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Ultra-fast 3D printing of assembly——free complex optics with sub-nanometer surface quality at mesoscale 被引量:1
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作者 Shuai Peng Jiawen Xu +4 位作者 Dongya Li Jun Ren Meng Zhang Xiaolong Wang Yu Liu 《International Journal of Extreme Manufacturing》 SCIE EI CAS CSCD 2023年第3期585-595,共11页
Complex-shaped optical lenses are of great interest in the areas of laser processing,machine vision,and optical communications.Traditionally,the processing of complex optical lenses is usually achieved by precision ma... Complex-shaped optical lenses are of great interest in the areas of laser processing,machine vision,and optical communications.Traditionally,the processing of complex optical lenses is usually achieved by precision machining combined with post-grinding or polishing,which is expensive,labor-intensive and difficult in the processing of ultra-complex optical lenses.Additive manufacturing is an emerging technology that provides significant advantages in producing highly intricate optical devices.However,the layer-by-layer method employed in such manufacturing processes has resulted in low printing speeds,as well as limitations in surface quality.To address these challenges,we apply tomographic volumetric printing(TVP)in this work,which can realize the integrated printing of complex structural models without layering.By coordinating the TVP and the meniscus equilibrium post-curing methods,ultra-fast fabrication of complex-shaped lenses with sub-nanometric roughness has been achieved.A2.5 mm high,outer diameter 9 mm spherical lens with a roughness value of RMS=0.3340 nm is printed at a speed of 3.1×10^(4)mm^(3)h^(-1).As a further demonstration,a complex-shaped fly-eye lens is fabricated without any part assembly.The designed spherical lens is mounted on a smartphone’s camera,and the precise alignments above the circuit board are captured.Upon further optimization,this new technology demonstrates the potential for rapid fabrication of ultra-smooth complex optical devices or systems. 展开更多
关键词 tomographic volumetric printing meniscus equilibrium post-curing methods spherical lens sub-nanometric roughness
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OPTICAL OPTIMIZATION FOR LIQUID CRYSTAL TEST BY LASER-CCD SYSTEM 被引量:2
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作者 Chang Ying Zhu Henian +1 位作者 Zhang Ziliang Yang Changxi 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2005年第3期464-466,共3页
For the narrowband of liner charge-coupled device (CCD) receiver and the imaging rule that cylindrical lens system can compress round facula into narrow and long one, the system is simplified and light force can con... For the narrowband of liner charge-coupled device (CCD) receiver and the imaging rule that cylindrical lens system can compress round facula into narrow and long one, the system is simplified and light force can concentrate on a strip facula, Considered the effective CCD length and selection of lens parameters, the system can be optimized. Correspondingly to the CCD pixels, the ray is composed of much angle information. By widening the parallel ray or increasing the lens aperture, luminous flux can be ensured when oblique incidence. Meanwhile, the effective working range can also be improved. Based on the experimental data, cylindrical system could be applied in accurate angle measurement. It has been proved feasible that the cylindrical system can be used in anchor behavior study for liquid crystal (LC) case. The low-power He-Ne laser cylindrical system can carry out the previous effect in high power laser spherical system. 展开更多
关键词 Linear CCD Cylindrical lens spherical lens Liquid crystal (LC)
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