On the possibility of application of kinoform and harmonic diffraction structures in constructions of phakic intraocular lenses

Abstract

Chromatic aberrations of the eye that arise upon application of diffraction structures such as Fresnel phase lenses with an ordinary (kinoform) or deep (harmonic) profile and diffraction-refraction (hybrid) structures in constructions of phakic (i.e., without lensectomy) intraocular lenses have been investigated analytically. Investigations have been done based on an eye model. It has been shown that, if kinoform (with a profile depth on the order of one wavelength) or hybrid structures are used, chromatic aberrations do not exceed 1 D (i.e., are comparable with aberrations of the ordinary eye) only in a positive range optical powers, which are restricted by the values of +7 and +15 D, respectively. If a harmonic structure is used (with a profile depth on the order of 20 wavelengths), the chromatic aberrations do not exceed 1 D in the entire interval of optical powers of phakic lenses from -25 to +15 D.