A Monte Carlo simulation of light propagation through the retina has been developed to understand the path-length distributions within the retinal vessel. For full-field illumination, the path-length distribution within the vessel comprises directly backscattered light and light that has passed once or twice through the vessel. The origins of these light path-length distributions can be better understood by investigating different combinations of single-point illumination and detection positions.
View Article and Find Full Text PDFPurpose: To assess the accuracy of human blood oximetry measurements in a model eye with a hyperspectral fundus camera.
Methods: Seven human whole blood samples (two arterial, five venous) were obtained, the oxygen saturations measured with a CO oximeter, and the samples inserted into quartz tubes with internal diameters of 100 and 150 μm. The tubes (n = 20; ten 100 μm and ten 150 μm) were placed within a model eye in front of a background reflectance surface with reflectivities of 20%, 60%, and 99%.
J Opt Soc Am A Opt Image Sci Vis
July 2007
The attenuation of light by scattering and absorbing media is nonlinearly dependent upon the absorption coefficient, since detected light has experienced many different flight times. The frequency response of such a sample to modulated light is also nonlinear. We derive an expression for the attenuation that includes both the absorption coefficient and the modulation frequency.
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