The Optical Integration technique for the measurement of light scatter in the human eye

Autor: Pablo Artal, Harilaos Ginis, Juan M. Bueno, Guillermo M. Pérez
Rok vydání: 2011
Předmět:
Zdroj: Acta Ophthalmologica. 89
ISSN: 1755-3768
1755-375X
DOI: 10.1111/j.1755-3768.2011.4326.x
Popis: Purpose To develop and demonstrate a new optical technique for the measurement of light scatter in the human eye based on extended source imaging in a double pass configuration. Methods The experimental setup is based on a double-pass (DP) configuration. Series of disks of uniform radiance having angular dimensions ranging from 0 to 9.1 degrees (radius) are projected on to the eye's retina and DP images are recorded by a cooled electron-multiplied CCD camera. Two spatially separated sub-apertures at the pupil are used for stimulus projection and imaging to minimise back-scatter and reflections. The derivative of the intensity of each recorded disk with respect to disk radius (in angular units) was fitted to a mathematical model of the wide-angle double pass point-spread function (PSF) and from that the underlying single-pass PSF was computed. The setup was first validated using artificial eyes with known scattering properties and used in a group of normal human eyes. Results The derivative of central disk intensity with respect to disk radius was measurable up to the complete range of the angular dimensions of the projected disks (9.1 degrees of visual field). Different features can be obtained from the estimated PSF to characterize not only the amount of scatter but also its angular dependence. Conclusion A new optical method to measure scatter in the eye was developed and demonstrated. The procedure is sensitive enough to consistently detect differences in the light scatter intensity between normal healthy eyes and can be a significant step towards the complete optical characterization of the eye.
Databáze: OpenAIRE
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