Sökning: "Peripheral aberrations"

Visar resultat 1 - 5 av 33 avhandlingar innehållade orden Peripheral aberrations.

  1. 1. Wavefront Aberrations and Peripheral Vision

    Författare :Linda Lundström; Peter Unsbo; Austin Roorda; KTH; []
    Nyckelord :NATURAL SCIENCES; NATURVETENSKAP; NATURVETENSKAP; NATURAL SCIENCES; Optics; Human eye; Aberrations; Peripheral vision; Central visual field loss; Optics; Optik;

    Sammanfattning : Failing eyesight causes a dramatic change in life. The aim of this project is to help people with large central visual field loss to better utilize their remaining vision. Central visual field loss means that the person has to rely on peripheral vision since the direct vision is lost, often due to a dysfunctional macula. LÄS MER

  2. 2. Peripheral Vision : Adaptive Optics and Psychophysics

    Författare :Robert Rosén; Peter Unsbo; Larry Thibos; KTH; []
    Nyckelord :NATURAL SCIENCES; NATURVETENSKAP; NATURVETENSKAP; NATURAL SCIENCES;

    Sammanfattning : This thesis is about our peripheral vision. Peripheral vision is poor compared to central vision, due to both neural and optical factors. The optical factors include astigmatism, defocus and higher order aberrations consisting mainly of coma. Neurally, the density of ganglion cells decreases towards the periphery, which limits the sampling density. LÄS MER

  3. 3. Optimal Use of Peripheral Vision

    Författare :Karthikeyan Baskaran; Jörgen Gustafsson; Peter Unsbo; Staffan Carius; Michael Crossland; Linnéuniversitetet; []
    Nyckelord :MEDICAL AND HEALTH SCIENCES; MEDICIN OCH HÄLSOVETENSKAP; MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; off-axis refractive errors; peripheral aberrations; aberrometers; central visual field loss; preferred retinal locus; eccentric viewing; absolute central scotoma; adaptive optics; eccentric correction.; Optometry; Optometri;

    Sammanfattning : People who lose their central vision have to rely on their peripheral vision for all visual tasks. The ability to resolve fine details in the periphery is reduced due to retinal limitations and the optical aberrations arising from the use of off-axis vision. LÄS MER

  4. 4. MANIPULATION OF OCULAR ABERRATIONS IN MYOPES

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

    Sammanfattning : 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%. LÄS MER

  5. 5. Myopia control and peripheral vision

    Författare :Petros Papadogiannis; Linda Lundström; Peter Unsbo; Nicola Logan; KTH; []
    Nyckelord :NATURAL SCIENCES; NATURVETENSKAP; NATURVETENSKAP; NATURAL SCIENCES; myopia; peripheral vision; psychophysics;

    Sammanfattning : The rapid rise in myopia prevalence has caused an urgent need for effectivemyopia control interventions. This thesis investigates the role of theperipheral optics of the human eye in myopia progression. It was initiallybelieved that the axial elongation of the myopic eye is caused only by thedefocus signals presented to the central retina. LÄS MER