Sökning: "refractive"

Visar resultat 1 - 5 av 219 avhandlingar innehållade ordet refractive.

  1. 1. Refractive Optics for Hard X-rays

    Författare :Björn Cederström; KTH; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; X-ray; focusing; refractive; optics; mammography; Physics; Fysik;

    Sammanfattning : .... LÄS MER

  3. 2. View Planning and Refractive Modeling for Structure and Motion

    Författare :Sebastian Haner; Matematik LTH; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; Computer Vision; Structure and Motion; 3D Reconstruction; View Planning; Refractive Modeling;

    Sammanfattning : This thesis presents contributions to structure-and-motion estimation, a central topic in the field of geometric computer vision. In particular, the problem of view planning is considered, and continuous and discrete optimization-based algorithms are given for how to plan the path of a sensor to its destination, while balancing the competing goals of path length and reconstruction accuracy. LÄS MER

  4. 3. A multi-prism lens for hard X-Rays

    Författare :Björn Cederström; KTH; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; x-ray; optics; refractive; lens; mammography; synchrotron; Physics; Fysik;

    Sammanfattning : This thesis describes a new type of refractive lens for hardx-rays. It is shown that a linear array of prisms, slightlyinclined with respect to the optical axis, will form a linefocus at a certain distance from the lens. Hence, the namemulti-prism lens. LÄS MER

  5. 4. Prevalence of refractive errors and incidence of myopia in Swedish schoolchildren

    Författare :Pelsin Demir; António Filipe Macedo; Karthikeyan Baskaran; Niall Strang; Linnéuniversitetet; []
    Nyckelord :MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; Refractive error; myopia; prevalence; incidence; risk factors; children; fovea; macula; autorefractor; aberrometer; synfel; refraktion; myopi; barn; prevalens; incidens; riskfaktorer; fovea; makula; autorefractor; aberrometer; Optometry; Optometri;

    Sammanfattning : PurposeThe aim of this thesis was to investigate the prevalence, incidence, and risk factors for myopia development in a cohort of Swedish schoolchildren. The specific goals were: - to recruit a cohort of children aged 8 to 16 years and to follow the cohort over a period of 24 months with regular study visits; - to investigate the predictive value of relative peripheral error and other optical parameters for the prevalence and incidence of myopia; - to determine and investigate the predictive value of genetic and environmental factors, and structural characteristics of the eye to the incidence of myopia. LÄS MER

  7. 5. Refractive surgery with the ArF excimer laser (photorefractive keratectomy) : surgical technique, wound healing and refractive results

    Författare :Heléne Hamberg-Nyström; Karolinska Institutet; Karolinska Institutet; []
    Nyckelord :Photorefractive keratectomy; excimer laser; comparison; centration; contrast sensitivity; night vision; endothelial cell; epithelial thickness; multipassmultizone; multizone; haze; saccades; hyaluronan; myopic regression; reoperation; wound healing.;

    Sammanfattning : Excimer lasers have been adapted to treat refractive errors in the human eye since 1987. By remodeling the corneal surface, myopia and astigmatism can be corrected. The investigations herein were performed during a time period when the surgical technique development was extensive. LÄS MER