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VISUAL DISABILITIES RELATED TO INTRAOCULAR LENS DESIGN

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Eye Science 1990年第Z1期15卷 36-39页

作者： Gerri Goodman Walter J.Stark John D.Gottsch Daniel Goodman Steven Olkowski A.E.Maumenee Ivan Escape Wilmer Ophthalmological Institute Johns Hopkins University School of Medccine Baltimore Maryland U. S. A.

Intraoeular. lens implantation after cataract extraction has become a common practice in the United States. However, unwanted optical images can correet an otherwise successful surgery into one that causes patient dissatisfaction. Refinements in manufacturing design and finishing have greatly improved the quality of present day intraocular lenses, but there is continued interest in simulating the optics of the human crystalline *** will discuss the optical requirements of intraocular lenses and how these are influenced by optic design and dimension, and spectral transmission characteristics.

关键词： intraocular cataract otherwise implantation crystalline optic VISUAL continued finishing aberration

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Wide field-of-view metalens: a tutorial

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Advanced Photonics 2023年第3期5卷 1-21页

作者： Fan Yang Mikhail YShalaginov Hung-I Lin Sensong An Anu Agarwal Hualiang Zhang Clara Rivero-Baleine Tian Gu Juejun Hu Massachusetts Institute of Technology Department of Materials Science and EngineeringCambridgeMassachusettsUnited States University of Massachusetts Lowell Department of Electrical and Computer EngineeringLowellMassachusettsUnited States Lockheed Martin Corporation OrlandoFloridaUnited States Massachusetts Institute of Technology Materials Research LaboratoryCambridgeMassachusettsUnited States

Wide field-of-view(FOV)optics are essential components in many optical systems,with applications spanning imaging,display,sensing,and beam *** refractive wide FOV optics often involve multiple stacked lenses,resulting in large size and weight as well as high *** lenses or metalenses promise a viable solution to realizing wide FOV optics without complex lens *** review the various architectures of wide FOV metalenses,elucidate their fundamental operating principles and design trade-offs,and quantitatively evaluate and contrast their imaging *** applications enabled by wide FOV metasurface optics are also discussed.

关键词： metasurface lens imaging field of view aberration

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Second Harmonic Conversion-efficiency of Aberrated Laser Beam

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Chinese Journal of Lasers 2001年第6期10卷 61-65页

作者： HOU Jin 1,2 ZHANG Yudong 1 JIANG Wenhan 1 1) Institute of Optics and Electronics, The Chinese Academy of Sciences, Chengdu 610209, China 2) Institute of Science, National University of Defense Technology, Changshe 410073,China 中科院光电技术所四川成都 610209

How aberrations of pump wave affect second harmonic generation is studied. The solution is applied to type I second harmonic generation in KDP crystal. The results of conversion-efficiency and transverse intensity distribution in second harmonic generation of Gaussian beam and super-Gaussian beam with aberrations of Zernike polynomials are presented.

关键词： second harmonic aberration conversion-efficiency Gaussian beam super-Gaussian beam

Comparison of visual performance between conventional LASIK and wavefront-guided LASIK with iris-registration

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Chinese Medical Journal 2008年第2期121卷 137-142页

作者： ZHANG Jing ZHOU Yue-hua WANG Ning-li LI Rui Ophthalmic Center Beijing Tongren Hospital Capital MedicalUniversity Beijing 100730 China

Background Laser in situ keratomileusis （LASIK） has become an efficient and commonly performed procedure to reduce refractive errors. In order to further increase the postoperative visual quality, the wavefront-guided refractive surgery has been a research hotspot in customized surgery. This study was conducted to compare the visual acuity, higher-order aberration, and contrast sensitivity of wavefront-guided LASIK with iris-registration and conventional LASIK. Methods Two hundred and eleven myopic eyes of 109 patients were enrolled in this prospective study and randomly divided into two groups： the wavefront-guided LASIK （wg LASIK） group （94 eyes） and conventional LASIK group （117 eyes）. A Wavescan Wavefront aberrometer was used to analyze Zernike coefficients and the root-mean-square （RMS） of higher order aberrations with 6.0 mm pupil size, and Optec 6500 visual function instrument was used to measure contrast sensitivity （CS） under 5 spatial frequencies before and after surgery in both groups.Results The uncorrected visual acuity （UCVA） and the mean spherical equivalent （SE） in wg LASIK group were significantly better than those in conventional LASIK （UCVA, z=2.339, P=0.019; SE, t=2.838, P=0.005） at 3 months after surgery. Moreover, the increase in Z3^-3, Z3^1, Z3^3, Z4^0, Z5^-1, Z5^1 Z5^-5 and Z6^-6 in wg LASIK group was statistically smaller than that in conventional LASIK group （P〈0.05）. In wg LASIK group, eyes with a higher amount of the preoperative RMS of the higher order aberrations （RMSh≥0.30μm） showed a statistically lower increase （13.5%） than those in conventional LASIK group at 3 months after surgery （33.3%）（P=0.004）. And the values of 4th order spherical aberration （4thSA） and the root mean square of 6th order aberration （RMS6） in wg LASIK group were significantly lower than those in conventional group in eyes which had higher preoperative astigmatism （≥1.0D）（4thSA, P=0.03; RMS6, P=0.02）. Wg LASIK group showed better CS values than the correspon

关键词： aberration contrast sensitivity visual performance keratomileusis, laser in situ

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A cylindricalÖffner stretcher based on ternary reflector for femtosecond petawatt-level laser system

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Chinese Optics Letters 2023年第7期21卷 69-73页

作者：李伟王逍左言磊洪义麟胡必龙吴朝辉母杰周凯南曾小明 National Synchrotron Radiation Laboratory University of Science and Technology of ChinaHefei 230026China Laser Fusion Research Center China Academy of Engineering PhysicsMianyang 621900China

A cylindricalÖffner stretcher based on ternary reflector(COSTER)is proposed and *** with the traditionalÖffner stretcher,the COSTER has no off-axis aberration in the multipass configuration,and the output laser of COSTER has lower spectral phase noise and higher temporal contrast in the far *** COSTER is quite suitable to be used in multipetawatt laser facilities,and it might be the preferred stretcher configuration for ultrafast and ultra-intense lasers.

关键词： cylindrical Offner stretcher aberration temporal contrast

Influence of Temperature on Mutagenicity in Plants Exposed to Surface Disinfected Drinking Water

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Journal of Water Resource and Protection 2012年第8期4卷 638-647页

作者： Bianca Gustavino Elisabetta Ceretti Claudia Zani Ilaria Zerbini Marco Rizzoni Silvano Monarca Donatella Feretti University of Brescia University of Perugia University of Rome “Tor Vergata”

Disinfection of surface drinking water, particularly water chlorination, produces by-products with potential genotoxic and/or carcinogenic activity. A study carried out at a pilot plant for drinking water disinfection of lake water revealed mutagenic activity of three different disinfectants (sodium hypochlorite, chlorine dioxide and peracetic acid) in different seasons using in situ mutagenicity assays, both in animal (micronucleus test) and in plant organisms (anaphase chromosomal aberration and micronucleus tests). The effects of the disinfectants appeared to be modulated by the season of exposure. In this study, we tried to understand if (and to what extent) the temperature parameter could actually play an independent role in the registered seasonal variation of mutagenic effects, neglecting the variation of other parameters, e.g. physical conditions and chemical composition of the lake water. Therefore plants (Allium cepa for chromosomal aberration test and Vicia faba for micronucleus test) were exposed to the same disinfected lake-water samples at different temperatures (10℃, 20℃ and 30℃), according the ones registered during the in situ experiment. Long-term expo- sure at the temperatures of 20℃ (both Vicia faba and Allium cepa) and 30℃ (Vicia faba only) to disinfected waters induced clear mutagenic effects. These results show that temperature is an important variable which should be taken into account when in situ exposure of plants is planned for mutagenicity testing. Also, different plant systems clearly show specific temperature ranges suitable for their growth, thereby indicating the need for an accurate selection of the test organism for a specific experimental plan.

关键词： Clastogenicity/Aneugenicity Allium cepa aberration Test Vicia faba Micronucleus Test Temperature Exposure Water Disinfection

Anatomic Variation in Palatal Root of Maxillary Second Molar: Endodontic Management

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Open Journal of Stomatology 2021年第4期11卷 159-165页

作者： Juan G. Robledo Pablo A. Rodriguez Endodontics Department School of Dentistry University of Buenos Aires Buenos Aires Argentina

The aim of the present clinical case report is to describe the singular root canal anatomy and endodontic management of a maxillary second molar with two palatal roots and two separate canal orifices. A 60 years-old female Hispanic/Latino patient attended the Endodontic Department at University of Buenos Aires School of Dentistry with acute pain in her maxillary left second molar. Clinical radiographs examination revealed unusual root morphology. Cleaning and shaping were completed with 5.25% NaOCl irrigation, 15% EDTA solution and hand/rotary instruments. Filling was performed with gutta-percha points and resin-based sealer. After one year follow-up periapical radiographs and CBCT images showed healing in the area and patient was asymptomatic.

关键词： aberration Anatomic Variation Maxillary Second Molar Two Palatal Roots

The Optical Properties of Gravity

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Journal of Modern Physics 2017年第5期8卷 803-838页

作者： Bernard Lavenda Pisgat Shoresh Apt 634 908600O Shoresh Israel

The resemblance between the equation for a characteristic hypersurface through which wavefronts of light rays pass and optical metrics of general relativity has long been known. Discontinuities in the hypersurface are due to refraction involving Snell’s law, as opposed to discontinuities in time that would involve the Doppler effect. The presence of a static gravitational potential in the metric coefficients is accounted by an index of refraction that is entirely dependent on the space coordinates. The two-time Einstein metric must be reinterpreted as a two-space scale metric because of the two different speeds of light. It is shown that the Schwarzschild metric is incompatible with the laws of classical physics. Gravitational waves are identified with the transverse-trans-verse plane wave solutions to Einstein’s equations in vacuum, which propagate at the speed of light. Yet, when energy loss is evaluated, his equations acquire, surprisingly, a source term. Poynting’s vector, which is not a true vector, is defined in terms of the pseudo-gravitational tensor, and hence energy is neither localizable nor conserved. The solutions to the equations of motion are geodesics and, by definition, do not radiate. A finite speed of propagation implies that gravitational waves should aberrate, like their electromagnetic wave counterparts, and if they do not aberrate they cannot radiate.

关键词： Gravitational Red-Shifts Optical Metrics Gravitational Geometrical Optics Gravitational aberration Refraction versus Doppler Shift Two-Time versus Two-Space Metrics Self-Energy of a Test Particle

Exact Equations for the Light Doppler Effect

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Journal of Modern Physics 2014年第16期5卷 1602-1607页

作者： Joseph J. Smulsky Institute of the Earth’s Cryosphere Siberian Branch of Russian Academy of Sciences Tyumen Russia

The influence of light source on the receiver as electromagnetic interaction is considered. The mechanical influence of the moving charged body on a motionless one is defined in the experimental laws of electrodynamics. These laws determine the changes of parameters of the light source that moves relatively the receiver. The laws of change of light frequency and its direction of the moving source are derived from the laws of electromagnetism. At small velocity of source movement they coincide with classical results: the Doppler effect and phenomenon of aberration. The interaction of the source and receiver depends only on their velocity of movement relatively each other. There is no world medium, the relative movement to which would influence the characteristics of light source.

关键词： Light Source Movement Relatively Receiver Laws of Electromagnetism Doppler Effect aberration