6533b820fe1ef96bd1279970

RESEARCH PRODUCT

Light transmission of the human lens and its relation with aging

subject

description

Purpose To determine the visible light transmission of the human crystalline lens of persons of different ages, using both solar and incandescent illumination. Methods The spectral transmission of lens was measured by using the Perkin-Elmer 800 UV/VIS spectrophotometer. With these data we calculated the percentage of visible light transmission for solar illumination, simulated by the CIE D65 illuminant, and for incandescent illumination (A illuminant). Results The total amount of visible light transmitted by nine crystalline lenses is represented as a function of age: with solar illumination and with incandescent illumination and the comparison between both illuminants.In general, the amount of visible light transmitted by the crystalline decreases with age and, in relative values, this transmission is higher with incandescent illumination (between 2 and 8% higher) than with solar illumination. Conclusion In general, total transmission of visible light decreases greatly with age.Nonetheless, the case of the transmission of a crystalline lens of a 50-year-old being much lower than that of a 64-year-old has been reported, which indicates that some of the factors that determine the darkening of the crystalline lens may act more intensely in some people than in others. Moreover, a slight improvement in visible light transmission was observed when incandescent light was used instead of solar light. This is because the crystalline lens yellows with age and as incandescent light is basically yellow, it is almost wholly transmitted. However, as solar light is tremendously intense, the absolute amount of light that reaches the retina is always much greater with solar rather than with incandescent illumination.