PURPOSE: To present a metric for assessing the in vitro optical quality of rotationally symmetrical optical elements based on volume calculation under the surface defined by the axial modulation transfer function (MTF). SETTING: University of Valencia, Valencia, Spain. DESIGN: Experimental study. METHODS: The metric volume under the axial MTF was used to assess the optical quality of 2 rotationally symmetrical multifocal intraocular lenses (IOLs) within various defocus intervals (0.50 diopter [D], 0.75 D, and 1.00 D) and at various spatial frequency intervals (7.5 cycles per degree [cpd], 15.0 cpd, and 30.0 cpd). RESULTS: The far focus of the bifocal IOL yielded higher volume values at all spatial frequencies and defocus intervals than the trifocal IOL. The results for the near focus were similar for both IOLs. In addition, the trifocal IOL provided a distinct focus for intermediate vision. CONCLUSIONS: The volume under the axial MTF proved to be a useful tool for objective evaluation of multifocal IOLs. Moreover, it can be applied to evaluate the optical quality of every rotationally symmetrical IOL or optical element. FINANCIAL DISCLOSURE: None of the authors has a financial or proprietary interest in any material or method mentioned.
PURPOSE: To present a metric for assessing the in vitro optical quality of rotationally symmetrical optical elements based on volume calculation under the surface defined by the axial modulation transfer function (MTF). SETTING: University of Valencia, Valencia, Spain. DESIGN: Experimental study. METHODS: The metric volume under the axial MTF was used to assess the optical quality of 2 rotationally symmetrical multifocal intraocular lenses (IOLs) within various defocus intervals (0.50 diopter [D], 0.75 D, and 1.00 D) and at various spatial frequency intervals (7.5 cycles per degree [cpd], 15.0 cpd, and 30.0 cpd). RESULTS: The far focus of the bifocal IOL yielded higher volume values at all spatial frequencies and defocus intervals than the trifocal IOL. The results for the near focus were similar for both IOLs. In addition, the trifocal IOL provided a distinct focus for intermediate vision. CONCLUSIONS: The volume under the axial MTF proved to be a useful tool for objective evaluation of multifocal IOLs. Moreover, it can be applied to evaluate the optical quality of every rotationally symmetrical IOL or optical element. FINANCIAL DISCLOSURE: None of the authors has a financial or proprietary interest in any material or method mentioned.
Authors: Teresa Ferrer-Blasco; Alberto Domínguez-Vicent; Santiago García-Lázaro; María Amparo Díez-Ajenjo; José F Alfonso; José J Esteve-Taboada Journal: Int J Ophthalmol Date: 2018-07-18 Impact factor: 1.779