The Experts below are selected from a list of 75 Experts worldwide ranked by ideXlab platform
Karolinne Maia Rocha - One of the best experts on this subject based on the ideXlab platform.
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Intraocular Lens Optics and aberrations.
Current opinion in ophthalmology, 2016Co-Authors: Daniel H. Chang, Karolinne Maia RochaAbstract:PURPOSE OF REVIEW This review outlines concepts in intraocular Lens (IOL) Optics and aberrations important both for current IOLs and for new IOLs in development. RECENT FINDINGS Optical aberrations make a significant impact on the laboratory and clinical performance of IOLs, especially under mesopic and low-contrast conditions. Minimizing or correcting these aberrations can potentially improve visual function. Strategic management of aberrations can have clinical utility for extended depth of focus and presbyopia correction. SUMMARY All IOLs affect ocular aberrations in some manner. It is important for clinicians and researchers to understand the implications how any residual aberrations could affect visual quality, visual side-effects, and depth of focus.
Michael Kuchle - One of the best experts on this subject based on the ideXlab platform.
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theoretical and measured pseudophakic accommodation after implantation of a new accommodative posterior chamber intraocular Lens
Archives of Ophthalmology, 2003Co-Authors: Achim Langenbucher, Berthold Seitz, Stefan M Huber, Nhung X Nguyen, Michael KuchleAbstract:Objective To analyze different techniques of measuring accommodation after implantation of a new accommodative posterior chamber intraocular Lens (PCIOL). Methods In this comparative, nonrandomized interventional study, we analyzed 15 eyes of 15 patients (aged 44-84 years) at 6 months after cataract surgery and PCIOL implantation (Akkommodative 1CU; Human Optics AG, Erlangen, Germany) and compared these results with those of an age-matched control group (n = 15). We used the following methods to measure accommodation: dynamic measurement with objective (videorefractometry [Power Refractor; Plus Optix, Erlangen] and streak retinoscopy) and subjective (subjective near point [push-up test and accommodometer] and defocusing) techniques, as well as static measurement of the change in anterior chamber depth (ACD) using the IOLMaster (Zeiss, Jena, Germany) after pharmacological stimulation using 2% pilocarpine eye drops. Main Outcome Measures Theoretical accommodation calculated from the forward shift of the Lens Optics (decrease of ACD) using paraxial geometrical Optics and measured accommodation amplitude. Results Accommodation amplitude (mean ± SD; range; median) results after 6 months in the study and control groups were as follows: 1.00 ± 0.44; 0.75-2.13; 1 diopter (D); and 0.35 ± 0.26; 0.10-0.65; 0.25 D, respectively, using the Power Refractor; 0.99 ± 0.48; 0.13-2.00; 0.88 D; and 0.24± 0.21; −0.13-0.75; 0.25 D, respectively, using retinoscopy; 1.6 ± 0.55; 0.50-2.56; 1.7 D; and 0.42 ± 0.25; 0.00-0.75; 0.50 D, respectively, using subjective near point; and 1.46 ± 0.53; 1.00-2.50; 1.75 D; and 0.55 ± 0.33; 0.25-0.87; 0.50 D, respectively, using defocusing. Anterior chamber depth decreased in the study and control groups as follows: 0.78 ± 0.12; 0.49-1.91; 0.65 mm; and 0.16 ± 0.09; 0.00-0.34; 0.18 mm, respectively, after applying 2% pilocarpine eyedrops, indicating an accommodation of 1.16 ± 0.22; 0.72-1.88; 1.05 D vs 0.22 ± 0.13; 0.00-0.47; 0.23 D ( P = .001). Conclusions Accommodation after implantation of a presumably accommodative PCIOL can be measured with clinical methods or derived from the biometric data of the eye and the measured ACD decrease using geometrical Optics. For clinical purposes, pseudophakic accommodation should be assessed with a variety of different techniques, including subjective and objective measurements. The theoretical approach using geometrical Optics may be an additional indicator for the accommodative response in patients with pseudophakic eyes and may allow a subdivision of the measured accommodation into true pseudophakic accommodation and pseudoaccommodation.
Elena Georgieva - One of the best experts on this subject based on the ideXlab platform.
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lorentz group in classical ray Optics
Journal of Optics B-quantum and Semiclassical Optics, 2004Co-Authors: S Baskal, Elena GeorgievaAbstract:It has been almost 100 years since Einstein formulated his special theory of relativity in 1905. He showed that the basic space–time symmetry is dictated by the Lorentz group. It is shown that this group of Lorentz transformations is not only applicable to special relativity, but also constitutes the scientific language for optical sciences. It is noted that coherent and squeezed states of light are representations of the Lorentz group. The Lorentz group is also the basic underlying language for classical ray Optics, including polarization Optics, interferometers, the Poincar´ es phere, one-Lens Optics, multi-Lens Optics, laser cavities, as well multilayer Optics.
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slide rule like property of wigner s little groups and cyclic s matrices for multilayer Optics
Physical Review E, 2003Co-Authors: Elena GeorgievaAbstract:It is noted that 2x2 "S" matrices in multilayer Optics can be represented by the Sp(2) group whose algebraic property is the same as the group of Lorentz transformations applicable to two spacelike and one timelike dimensions. It is also noted that Wigner's little groups have a slide-rule-like property that allows us to perform multiplications by additions. It is shown that these two mathematical properties lead to a cyclic representation of the S matrix for multilayer Optics, as in the case of ABCD matrices for laser cavities. It is therefore possible to write the N-layer S matrix as a multiplication of the N single-layer S matrices resulting in the same mathematical expression with one of the parameters multiplied by N. In addition, it is noted, as in the case of Lens Optics, that multilayer Optics can serve as an analog computer for the contraction of Wigner's little groups for internal space-time symmetries of relativistic particles.
Daniel H. Chang - One of the best experts on this subject based on the ideXlab platform.
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Intraocular Lens Optics and aberrations.
Current opinion in ophthalmology, 2016Co-Authors: Daniel H. Chang, Karolinne Maia RochaAbstract:PURPOSE OF REVIEW This review outlines concepts in intraocular Lens (IOL) Optics and aberrations important both for current IOLs and for new IOLs in development. RECENT FINDINGS Optical aberrations make a significant impact on the laboratory and clinical performance of IOLs, especially under mesopic and low-contrast conditions. Minimizing or correcting these aberrations can potentially improve visual function. Strategic management of aberrations can have clinical utility for extended depth of focus and presbyopia correction. SUMMARY All IOLs affect ocular aberrations in some manner. It is important for clinicians and researchers to understand the implications how any residual aberrations could affect visual quality, visual side-effects, and depth of focus.
Akio Suzuki - One of the best experts on this subject based on the ideXlab platform.
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nonimaging fresnel Lenses design and performance of solar concentrators
2012Co-Authors: Akio Suzuki, Ralf LeutzAbstract:Executive Summary.- 1 Lenses and Mirrors for Solar Energy.- 1.1 Photovoltaic or Thermal Concentration?.- 1.2 Classification of Solar Concentrators.- 2 Nonimaging Optics.- 2.1 Nonimaging Concentration.- 2.2 Generalized Ideal Concentration.- 2.3 Lagrange Invariant.- 2.4 Nonimaging Mirrors.- 3 Fresnel Lens Optics.- 3.1 Reflection and Refraction.- 3.2 Total Internal Reflection.- 3.3 Deviation.- 3.4 Refractive Indices.- 3.5 Minimum Dispersion.- 4 Earlier Fresnel Lenses.- 4.1 History of Fresnel Lenses.- 4.2 Recent Developments.- 4.3 Simple Fresnel Lenses.- 4.4 Domed or Arched Fresnel Lenses.- 5 Nonimaging Fresnel Lens Design.- 5.1 Applied Nonimaging Lens Design.- 5.2 The Optimum Linear Lens.- 5.3 Rotational Symmetry.- 5.4 Arbitrary Shapes.- 5.5 Diverger Lens for Lighting.- 6 Lens Evaluation.- 6.1 Losses.- 6.2 Transmittance.- 6.3 Geometrical Losses.- 6.4 Concentration Ratios.- 6.5 Nonideal Concentration.- 7 Optimization of Stationary Concentrators.- 7.1 Choice of Stationary Collector.- 7.2 Solar Radiation Model.- 7.3 Radiation on a Tilted Plane.- 7.4 Acceptance by a Solar Concentrator.- 7.5 Compound Parabolic Concentrators.- 7.6 Quasi-3D Concentrators.- 8 Prototype Design, Manufacturing, and Testing.- 8.1 Prototypes of Choice.- 8.2 Prism Size.- 8.3 Lens Redesign.- 8.4 Lens Manufacturing.- 8.5 Sample.- 8.6 Preliminary Tests.- 8.7 Partial Absorber Illumination.- 8.8 Tracking.- 9 Concentrated Sunlight and Photovoltaic Conversion.- 9.1 Flux Density.- 9.2 Solar Disk Size and Brightness.- 9.3 Spectral Color Dispersion.- 9.4 Concentrator Cells.- 9.5 Multijunction Devices.- 9.6 Photovoltaic System Performance.- 9.7 Concentration and Cost.- 10 Solar Thermal Concentrator Systems.- 10.1 Solar Resources.- 10.2 Solar Sorption Air Conditioning.- 10.3 Energy and Exergy.- 10.4 Exergy of a Concentrating Collector.- 11 Solar Concentration in Space.- 11.1 Space Concentrator Arrays.- 11.2 Design Challenges in Space.- 11.3 Lenses and Mirrors!.- References.
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nonimaging fresnel Lenses design and performance of solar concentrators
2001Co-Authors: Ralf Leutz, Akio SuzukiAbstract:Executive Summary.- 1 Lenses and Mirrors for Solar Energy.- 1.1 Photovoltaic or Thermal Concentration?.- 1.2 Classification of Solar Concentrators.- 2 Nonimaging Optics.- 2.1 Nonimaging Concentration.- 2.2 Generalized Ideal Concentration.- 2.3 Lagrange Invariant.- 2.4 Nonimaging Mirrors.- 3 Fresnel Lens Optics.- 3.1 Reflection and Refraction.- 3.2 Total Internal Reflection.- 3.3 Deviation.- 3.4 Refractive Indices.- 3.5 Minimum Dispersion.- 4 Earlier Fresnel Lenses.- 4.1 History of Fresnel Lenses.- 4.2 Recent Developments.- 4.3 Simple Fresnel Lenses.- 4.4 Domed or Arched Fresnel Lenses.- 5 Nonimaging Fresnel Lens Design.- 5.1 Applied Nonimaging Lens Design.- 5.2 The Optimum Linear Lens.- 5.3 Rotational Symmetry.- 5.4 Arbitrary Shapes.- 5.5 Diverger Lens for Lighting.- 6 Lens Evaluation.- 6.1 Losses.- 6.2 Transmittance.- 6.3 Geometrical Losses.- 6.4 Concentration Ratios.- 6.5 Nonideal Concentration.- 7 Optimization of Stationary Concentrators.- 7.1 Choice of Stationary Collector.- 7.2 Solar Radiation Model.- 7.3 Radiation on a Tilted Plane.- 7.4 Acceptance by a Solar Concentrator.- 7.5 Compound Parabolic Concentrators.- 7.6 Quasi-3D Concentrators.- 8 Prototype Design, Manufacturing, and Testing.- 8.1 Prototypes of Choice.- 8.2 Prism Size.- 8.3 Lens Redesign.- 8.4 Lens Manufacturing.- 8.5 Sample.- 8.6 Preliminary Tests.- 8.7 Partial Absorber Illumination.- 8.8 Tracking.- 9 Concentrated Sunlight and Photovoltaic Conversion.- 9.1 Flux Density.- 9.2 Solar Disk Size and Brightness.- 9.3 Spectral Color Dispersion.- 9.4 Concentrator Cells.- 9.5 Multijunction Devices.- 9.6 Photovoltaic System Performance.- 9.7 Concentration and Cost.- 10 Solar Thermal Concentrator Systems.- 10.1 Solar Resources.- 10.2 Solar Sorption Air Conditioning.- 10.3 Energy and Exergy.- 10.4 Exergy of a Concentrating Collector.- 11 Solar Concentration in Space.- 11.1 Space Concentrator Arrays.- 11.2 Design Challenges in Space.- 11.3 Lenses and Mirrors!.- References.