Volume 52, Issue 1 And 2 (30 1994)                   Tehran Univ Med J 1994, 52(1 And 2): 77-84 | Back to browse issues page

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Abstract:   (3533 Views)
The diffractive multifocal IOL provides simultaneous bifocal imaging by utilizing both diffractive and refractive optics. In both distant and near vision, there is a clear highly focused image on the retina. The second image is highly defocused, providing only faint background illumination. A small amount of the light goes to the higher orders of diffraction which are not perceptible by eyes. The bright spot produced by a zone plate is so intense that the plate acts much like a converging lens. There are also fainter images corresponding to focal lengths f/3, f/5, f/7, ...
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