Evans, Tanya Harris, William F
Published in
Journal of the Optical Society of America. A, Optics, image science, and vision
Ellipses are features of several structures in astigmatic eyes; they include retinal blur patches. How can one calculate change or averages or perform other quantitative analyses on such elliptical structures? The matrix A in the equation rTAr=1, commonly used to represent an ellipse, is positive definite; such matrices do not define vector spaces....
Wang, Kehao Hoshino, Masato Uesugi, Kentaro Yagi, Naoto Pierscionek, Barbara K
Published in
Journal of the Optical Society of America. A, Optics, image science, and vision
Ageing changes to the various components of the accommodative system of the eye lens contribute to the loss of focusing power. The relative contributions of each ageing component, however, are not well defined. This study investigates the contribution of geometric parameters and material properties on accommodation, simulated using models based on ...
Temple, Shelby E Roberts, Nicholas W Misson, Gary P
Published in
Journal of the Optical Society of America. A, Optics, image science, and vision
Macular pigments (MPs), by absorbing potentially toxic short-wavelength (400-500 nm) visible light, provide protection against photo-chemical damage thought to be relevant in the pathogenesis of age-related macular degeneration (AMD). A method of screening for low levels of MPs could be part of a prevention strategy for helping people to delay the ...
Boszczyk, Agnieszka Kasprzak, Henryk Siedlecki, Damian
Published in
Journal of the Optical Society of America. A, Optics, image science, and vision
The aim of this study was to determine characteristic frequencies of corneal vibrations occurring during air-puff intraocular pressure (IOP) measurement using the Corvis ST tonometer. Relations of frequency of the corneal vibrations with IOP were examined. Two selected vibration frequencies-frequency with maximum amplitude, and mass center of the f...
Aldaba, Mikel Mira-Agudelo, Alejandro Barrera Ramírez, John Fredy García-Guerra, Carlos Enrique Ramo, Jaume Pujol
Published in
Journal of the Optical Society of America. A, Optics, image science, and vision
Tear film stability assessment is one of the main tests in dry eye diagnosis. However, to date, no test methodology has been adopted as the gold standard due to several reasons, such as the methods being invasive, subjective, or unfeasible for the clinical environment. In this paper, a method that overcomes the above-mentioned limitations for tear ...
Llorens-Quintana, Clara Szczesna-Iskander, Dorota H Robert Iskander, D
Published in
Journal of the Optical Society of America. A, Optics, image science, and vision
Placido disk videokeratoscopy, when used in a dynamic acquisition mode, can be utilized for noninvasive assessment of tear film quality. The different commercially available videokeratoscopes that incorporate an automatic option to evaluate tear film do not provide consistent measurements due to differences in their designs as well as differences i...
Misson, Gary P Temple, Shelby E Anderson, Stephen J
Published in
Journal of the Optical Society of America. A, Optics, image science, and vision
Recent studies on polarization perception have shown that humans are sensitive to patterned stimuli modulated by either angle of linear polarization (AoP) or degree of polarization (DoP). Here, we present a model of human polarization sensitivity that incorporates both AoP and DoP as spatially dependent input variables. Applying the model to both s...
Huang, Xiyong Protheroe, Michael D Al-Jumaily, Ahmed M Chalmers, Andrew N Paul, Sharad P Fu, Xiang
Published in
Journal of the Optical Society of America. A, Optics, image science, and vision
The incidence of melanoma in children is extremely rare. However, there is convincing evidence supporting a higher risk of developing melanoma in individuals who have experienced excessive sun exposure during their childhood. A possible explanation for this phenomenon is that prior to puberty, the melanocyte stem cells in the bulge region of hair f...
Trindade, Bruno Lovaglio Cançado Amaral, Felipe Tayer de Lima Monteiro, Davies William Cronemberger, Sebastião
Published in
Journal of the Optical Society of America. A, Optics, image science, and vision
This paper proposes a customized and versatile optical setup to evaluate the optical performance of different commercially available intraocular lenses (IOLs). The setup was used to measure the wavefront error induced by different IOL models, verifying and analyzing the magnitude of low- and high-order aberrations induced by currently available IOL...
Benito, Antonio Bueno, Juan M Pérez, Guillermo M Artal, Pablo
Published in
Journal of the Optical Society of America. A, Optics, image science, and vision
Tear-film dynamics were analyzed by a synchronizing recording of double-pass (DP) and pupil retro-illumination (RI) images with contrast sensitivity (CS) measurements. Simultaneous DP and RI images were acquired in three subjects wearing contact lenses while keeping the eye open. Changes in contrast sensitivity for an 18 c/deg green grating were al...