Search for dissertations about: "Spherical aberration"

Showing result 1 - 5 of 9 swedish dissertations containing the words Spherical aberration.

2. 1. MULTIFOCAL SPHERICAL FISH LENSES

   Author : Yakir Gagnon; Biologiska institutionen; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; Multifocal Lens; Adaptation; Dispersion; Spherical lens; Model; Fish; Ray-trace; Longitudinal Chromatic Aberration; Longitudinal Spherical Aberration; Modulation Transfer Function; Point Spread Function; Refractive Index Gradient;

   Abstract : Vision is an important source of information for many animals. The lens plays a central role in the visual pathway and hence the ecology of these animals. Fish have spherically shaped crystalline lenses that contain a gradient of refractive index. Like all refracting elements, lens performance depends on the wavelength of the refracted light. READ MORE

4. 2. Manipulation of Ocular Aberrations in Myopes

   Author : Baskar Theagarayan; Jörgen Gustafsson; Frank Schaeffel; Linnéuniversitetet; []
   Keywords : MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; Myopia; Spherical aberration; Accommodation; Contact lens; Visual acuity; Peripheral aberrations; Optometry; Optometri; Optometry; Optometri;

   Abstract : Myopia is a major cause of vision loss throughout the world. High myopia is associated with severe eye diseases like maculopathy, retinal detachment and glaucoma. The prevalence of myopia is increasing, and varies by country and by ethnic group. In some Asian populations the prevalence is 70%-80%. READ MORE

5. 3. Ocular aberrations and visual quality in aspherical and multifocal contact lenses

   Author : Anna Lindskoog Pettersson; Karolinska Institutet; Karolinska Institutet; []
   Keywords : Contact lenses;

   Abstract : Good visual quality and precise accommodation are required to be able to focus objects at distance and near, and are essential in order to be able to perform most tasks in life. Most eyes are not ideal eyes, i.e., they have different refractive errors which distort the produced image. READ MORE

6. 4. Extremely Large Telescopes Optical Design and Wavefront Correction

   Author : Alexander Gontcharov; Astronomi - Genomgår omorganisation; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; Astronomy; akustik; optik; Adaptive Optics; Extremely Large Telescopes; optical design methods; wavefront correction methods.; Electromagnetism; optics; Elektromagnetism; acoustics; space research; cosmic chemistry; Astronomi; rymdvetenskap; kosmisk kemi;

   Abstract : An overview of the state of art within optical design of large astronomical telescopes is given. Recent advances within the field are presented. The importance of new computer-controlled mirror-polishing methods is emphasized. READ MORE

7. 5. Comparative optics of prosobranch eyes

   Author : Jan-Olof Seyer; Biologiska institutionen; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; Ampularia; Littorina; Strombus; evolution; visual ecology; summation; convergence; optic nerve; resolution; sensitivity; optics; eye; gastropod; prosobranch; Animal anatomy; animal morphology; Djurs anatomi och morfologi;

   Abstract : Functional aspects of the large diversity of eye design in prosobranch molluscs was investigated using morphological and optical methods. Three species from different habitats were investigated. Littorina littorea from Scandinavian intertidal rock habitats, Strombus raninus and S. gigas from tropical sand-flats and Ampularia sp. READ MORE