optics of diffractive multifocal iol

نویسندگان

بهرام فتاحی

b fatahi

چکیده

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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عنوان ژورنال:
مجله دانشکده پزشکی دانشگاه علوم پزشکی تهران

جلد ۵۲، شماره ۱، صفحات ۷۷-۸۴

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