The optical design of the fish eye is particularly simple because immersion renders the cornea optically ineffective and the lens is nearly spherical in shape. Measurements have shown that an approximately parabolic gradient of refractive index exists within the lens. If full internal and external spherical symmetry of the lens applies, the geometrical-optical behaviour of the lens is then a fu...

PURPOSE To investigate the refractive outcomes and spherical aberration of multifocal LASIK to create a distant-dominant center and near-dominant periphery in hyperopic, myopic, and emmetropic presbyopia. METHODS One hundred ninety-five eyes with myopic presbyopia and 119 eyes with hyperopic or emmetropic presbyopia that underwent LASIK or epithelial LASIK (epi-LASIK) were assessed out to 3 m...

The efficiency of trapping an on-axis spherical particle by use of laser tweezers for a particle size from the Rayleigh limit to the ray optics limit is calculated from generalized Lorenz-Mie light-scattering theory and the localized version of a Gaussian beam that has been truncated and focused by a high-numerical-aperture lens and that possesses spherical aberration as a result of its transmi...

PURPOSE To evaluate intraindividual visual acuity, wavefront errors and modulation transfer functions in patients implanted with two diffractive multifocal intraocular lenses. METHODS This prospective study examined 40 eyes of 20 cataract patients who underwent phacoemulsification and implantation of a spherical multifocal ReSTOR intraocular lens in one eye and an aspheric Tecnis ZM900 multif...

By optimum combination of optical pre-processing and digital post-processing, or optical coding and digital decoding of the image information, incoherent optical systems invariant to numerous aberrations can be formed. The theory of aberration invariance can also be used with low-cost, low-precision optics to produce systems that image with the performance of high-cost, high-precision, or near ...

The resolution of conventional electron microscopes is usually limited by spherical aberration. Microscopes equipped with aberration correctors are then primarily limited by higher order, chromatic, and misalignment aberrations. In particular the Nion third-order aberration correctors installed on machines with a low energy spread and possessing sophisticated alignment software were limited by ...

Scanning confocal electron microscopy (SCEM) is a new imaging mode in electron microscopy. Spherical aberration corrected electron microscope instruments fitted with two aberration correctors can be used in this mode which provides improved depth resolution and selectivity compared to optical sectioning in a conventional scanning transmission geometry. In this article, we consider the depth res...

Recent research in the area of electro-optical system design identified the benefits of spherical aberration for extending the depth-of-field of electro-optical imaging systems. In such imaging systems, spherical aberration is deliberately introduced by the optical system lowering system modulation transfer function (MTF) and then subsequently corrected using digital processing. Previous resear...