Image formation by bifocal lenses in a trilobite eye?
نویسندگان
چکیده
منابع مشابه
Image formation by bifocal lenses in a trilobite eye?
In this work we report on a unique and ancient type of eye, in which the lower surface of the upper calcite lens units possessed an enigmatic central bulge making the dioptric apparatus similar to a bifocal lens. This eye belonged to the trilobite Dalmanitina socialis, which became extinct several hundred million years ago. As far as we know, image formation by bifocal lenses of this kind did/d...
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Almost all animal eyes follow a few, relatively well-understood functional plans. Only rarely do researchers discover an eye that diverges fundamentally from known types. The principal eye E2 of sunburst diving beetle (Thermonectus marmoratus) larvae clearly falls into the rarer category. On the basis of two different tests, we here report that it has truly bifocal lenses, something that has be...
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15 صفحه اولMyopia Control with Bifocal Contact Lenses: A Randomized Clinical Trial.
PURPOSE Most studies have reported only minimal reductions in myopia progression with bifocal or progressive multifocal spectacles, although somewhat larger, although mostly still clinically insignificant, effects have been reported in children with nearpoint esophoria and/or accommodative dysfunctions. The CONTROL study was a 1-year, prospective, randomized, clinical trial of bifocal contact l...
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ژورنال
عنوان ژورنال: Vision Research
سال: 2000
ISSN: 0042-6989
DOI: 10.1016/s0042-6989(99)00216-3