title: Perceived image quality with simulated segmented bifocal corrections.
abstract: Bifocal contact or intraocular lenses use the principle of simultaneous vision to correct for presbyopia. A modified two-channel simultaneous vision simulator provided with an amplitude transmission spatial light modulator was used to optically simulate 14 segmented bifocal patterns (+ 3 diopters addition) with different far/near pupillary distributions of equal energy. Five subjects with paralyzed accommodation evaluated image quality and subjective preference through the segmented bifocal corrections. There are strong and systematic perceptual differences across the patterns, subjects and observation distances: 48% of the conditions evaluated were significantly preferred or rejected. Optical simulations (in terms of through-focus Strehl ratio from Hartmann-Shack aberrometry) accurately predicted the pattern producing the highest perceived quality in 4 out of 5 patients, both for far and near vision. These perceptual differences found arise primarily from optical grounds, but have an important neural component.
authors.affiliation: Laboratory of Visual Optics and Biophotonics, Instituto de Optica, Consejo Superior de Investigaciones Cientificas, Serrano 121, 28006 Madrid, Spain.
authors.forename: Carlos
authors.initials: C
authors.lastname: Dorronsoro
authors.affiliation: Laboratory of Visual Optics and Biophotonics, Instituto de Optica, Consejo Superior de Investigaciones Cientificas, Serrano 121, 28006 Madrid, Spain; Currently with Image Processing and Computer Vision Lab, Department of Electrical Engineering, Indian Institute of Technology, Madras, Chennai, India.
authors.forename: Aiswaryah
authors.initials: A
authors.lastname: Radhakrishnan
authors.affiliation: Laboratory of Visual Optics and Biophotonics, Instituto de Optica, Consejo Superior de Investigaciones Cientificas, Serrano 121, 28006 Madrid, Spain; Currently with Midwestern University, Chicago College of Optometry, 555 31st St., Downers Grove, IL 60515, USA.
authors.forename: Pablo
authors.initials: P
authors.lastname: de Gracia
authors.affiliation: Laboratory of Visual Optics and Biophotonics, Instituto de Optica, Consejo Superior de Investigaciones Cientificas, Serrano 121, 28006 Madrid, Spain; Currently with Laboratorio de Óptica, Instituto Universitario de Investigación en Óptica y Nanofísica, Universidad de Murcia, Campus de Espinardo (Edificio 34), 30100 Murcia, Spain.
authors.forename: Lucie
authors.initials: L
authors.lastname: Sawides
authors.affiliation: Laboratory of Visual Optics and Biophotonics, Instituto de Optica, Consejo Superior de Investigaciones Cientificas, Serrano 121, 28006 Madrid, Spain.
authors.forename: Susana
authors.initials: S
authors.lastname: Marcos
keywords: (330.0330) Vision, color, and visual optics; (330.4300) Vision system - noninvasive assessment; (330.4460) Ophthalmic optics and devices; (330.4595) Optical effects on vision; (330.7327) Visual optics, ophthalmic instrumentation