BACKGROUND Intrascleral fixation of an intraocular lens (IOL) is used in eyes that lack capsular support. The aim of the study is to determine whether a larger optical diameter IOL will decrease the higher-order aberrations (HOAs) when the haptics are extended for intrascleral fixation than a smaller diameter IOL. METHODS Three-piece acrylic IOLs with 6.0 mm optics (X-60, VA-60BBR) and 7.0 mm...

Operation of an X-ray spectrometer based on a spherical variable-line-spacing (VLS) grating is analyzed using dedicated ray-tracing software allowing fast optimization of the grating parameters and spectrometer geometry. The analysis is illustrated with optical design of a model spectrometer to deliver a resolving power above 20400 at a photon energy of 930 eV (Cu L-edge). With this energy take...

We demonstrate an approach for improving the image quality for a projector system with a shape-programmable pupil, which could be generated by an illumination modular in which a digital micromirror device is embedded. Essentially, the shaped pupil from the illumination modulator is developed with a dynamically programmable approach to provide aberration compensation for the projection system. B...

The alignment of three mirror anastigmatic (TMA) telescopes has been studied since their invention in the 60s. Recently, Thompson et al. reported that other than the conventional uniform coma over the field caused by misalignment, TMA telescopes display only one other misalignment induced aberration, field-asymmetric, field-linear astigmatism. Currently, an instrument with three TMAs is under d...

Purpose. To evaluate decentration following femtosecond laser small incision lenticule extraction (SMILE) and sub-Bowman keratomileusis (SBK) and its impact on higher-order aberrations (HOAs). Methods. Prospective, nonrandom, and comparison study. There were 96 eyes of 52 patients who received SMILE and 96 eyes of 49 patients who received SBK in this study. Decentration was calculated 6 months ...

A novel astigmatism-free spectrograph design, the Princeton Instruments SCT 320 IsoPlane Schmidt-Czerny-Turner (SCT) spectrograph, is shown to give Raman spectra with better resolution and signal-to-noise ratios than traditional Czerny-Turner (CT) spectrographs. A single-stage SCT spectrograph has been interfaced to a new low-frequency Raman spectroscopy module that uses volume phase holographi...

PURPOSE To study the sequential postblink changes in ocular higher-order aberrations (HOAs) in patients with dry eye. METHODS A wavefront sensor was used to measure HOAs sequentially for 30 seconds in 20 eyes of 20 patients with dry eye. The 20 eyes were classified into two groups, with or without superficial punctate keratopathy (SPK) in the central cornea. During the measurement, subjects w...

PURPOSE To study the effect of small-incision cataract surgery on the optical aberrations of the cornea. METHODS Corneal topography was measured before and after cataract surgery on 70 eyes of 70 patients. Monofocal foldable IOLs were implanted after phacoemulsification through a clear-cornea, 3.5-mm incision without suture. Corneal aberrations, up to the fifth order and 6-mm pupil, were calc...

We previously showed that different types of aberration defocus, coma, and secondary astigmatism affect reading performance via different mechanisms. In this paper, we show the contrary result that, for identification of isolated letters, the effects of rendering different types of aberration can be described by a single cross-correlation-based metric. Aberrations reduce the effective resolutio...

PURPOSE To compare the mean change in aberrations produced by a mechanical microkeratome and femtosecond laser. METHODS This was a retrospective study of 62 consecutive near emmetropic eyes that underwent LASIK and satisfied the following criteria: negligible laser ablation (for spherical equivalent of 0.00 to +0.50 diopters and maximum meridian of +0.50 diopters), and preoperative and at lea...