title: Optical properties of in situ eye lenses measured with X-ray Talbot interferometry: a novel measure of growth processes.
abstract: The lens, a major optical component of the eye, has a gradient refractive index, which is required to provide sufficient refractive power and image quality. The refractive index variations across the lens are dependent on the distributions and concentrations of the varying protein classes. In this study, we present the first measurements of the refractive index in the in situ eye lens from five species using a specially constructed X-ray Talbot grating interferometer. The measurements have been conducted in two planes: the one containing the optic axis (the sagittal plane) and the plane orthogonal to this (the equatorial plane). The results show previously undetected discontinuities and fluctuations in the refractive index profile that vary in different species. These may be linked to growth processes and may be the first optical evidence of discrete developmental stages.
authors.affiliation: Japan Synchrotron Radiation Research Institute (SPring8), Sayo, Hyogo, Japan.
authors.forename: Masato
authors.initials: M
authors.lastname: Hoshino
authors.forename: Kentaro
authors.initials: K
authors.lastname: Uesugi
authors.forename: Naoto
authors.initials: N
authors.lastname: Yagi
authors.forename: Satoshi
authors.initials: S
authors.lastname: Mohri
authors.forename: Justyn
authors.initials: J
authors.lastname: Regini
authors.forename: Barbara
authors.initials: B
authors.lastname: Pierscionek
mesh_terms: D000818:Animals; D005399:Fishes; D007368:Interferometry; D007908:Lens, Crystalline / Q000033:anatomy & histology / Q000254:growth & development*; D051379:Mice; D008954:Models, Biological; D055095:Optics and Photonics; D057078:Pentastomida; D012029:Refraction, Ocular / Q000502:physiology*; D012031:Refractometry; D013552:Swine; D014965:X-Rays