Alvaro M Pons

University of Valencia | UV · Departamento de Óptica

Purpose: To assess the effects on the spontaneous blinking pattern and blinking kinematics of cataract surgery. Setting: FISABIO Oftalmología Médica (FOM) eye hospital, Valencia, Spain. Design: Observational, descriptive, clinical study. Methods: Patients with senile cataract were evaluated before (visit 1), and 1 month (visit 2) and 3 month...

Reseña del libro: JOSÉ MANUEL TRABADO. (ED.). Lenguajes gráfico-narrativos. Especifidades, intermedialidades y teorías gráficas. Gijón: Editorial Trea, 2022.

Purpose This study aimed to assess the differences in blinking kinematics while reading on different digital displays and a control condition. Methods Thirty-two young healthy individuals were included in this prospective clinical study. The blinks of subjects were recorded for 150 s while reading on a laptop computer, tablet, e-reader, and smartp...

La exposición El dibujado, de Paco Roca (IVAM, 2019) es una exploración en el cambio de paradigma que supone el abandono del papel y la reproductibilidad como espacio de difusión de la historieta. La sala de exposiciones de un museo se configura como un espacio de experimentación formal y efímera a diferentes niveles, desde el puramente creativo al...

La ciudad de Valencia contará con el nuevo Centro de Estudios y Conservación del Cómic. El Ayuntamiento de la ciudad y el Vicerrectorado de Cultura de la Universitat de Valencia (UV), a través de su Aula del Cómic, colaborarán en la gestión y coordinación de las actividades del futuro espacio cultural así como en la dotación y ampliación de las col...

PurposeThe objective of this study was to analyze the differences in blinking kinematics of spontaneous and voluntary blinks using for the first time a self-developed, non-invasive, and image processing–based method.Methods The blinks of 30 subjects were recorded for 1 min with the support of an eye-tracking device based on a high-speed infrared vi...

Significance: Digital display use has been accepted as a contributing factor to dry eye disease. Nowadays, plenty of new models of digital displays have been developed, and the differences in their nature and the ways in which they are set and used may contribute to differences in the eye-related problems they cause. Purpose: This study aimed to...

p>El diseño gráfico es importante y necesario en el mundo de hoy porque la vista es la principal forma de adquisición de información. Por lo tanto, es lógico pensar que las ciencias de la visión pueden ayudar en la toma de decisiones a nivel de diseño. Comprender conceptos como la agudeza visual, la sensibilidad al contraste, entre otros, contribui...

En este trabajo se analiza la obra de un autor de origen español bien conocido en el cómic francés, Tiburcio de la Llave, conocido como Tito. Pese a ser uno de los pioneros en la representación de la Guerra Civil en el cómic, la obra de Tito es prácticamente desconocida en España. En esta investigación, los autores se centran en sus dos series más...

Experimental cathodic fanzinism from Spain. In the last decade, small press and self-publishing has undergone an important boom in Spain, mainly around two phenomena: on the one hand, the generalization of the introduction of comics in higher art studies; on the other hand, the appearance of a circuit of festivals and events of self-publishing and...

La poesía gráfica se ha consolidado en los últimos años como uno de los campos de experimentación del cómic más activo y fructífero. La exploración de las posibilidades del cómic alejadas de la tradicional narratividad secuencial ha permitido entroncar la narración visual con la poesía concreta y caligramática, encontrando una relación cuya natural...

Aim: To determine the presence of symptomatic accommodative and non-strabismic binocular dysfunctions (ANSBD) in a non-presbyopic population of video display unit (VDU) users with flat-panel displays. Methods: One hundred and one VDU users, aged between 20 to 34y, initially participated in the study. This study excluded contact-lens wearers and...

En este trabajo se analiza la aparición de una nueva tendencia de creación de vanguardia en el cómic español, que nace desde los fanzines para explorar nuevos caminos que van más allá de la narrativa tradicional. Para ello, se investiga la aparición del lenguaje poético dentro del noveno arte y su conexión con otras formas previas de la literatura...

The measurement and modeling of image quality are aimed to assist the design and optimization of systems, typically built for 'normal' observer vision. But in reality image viewers rarely have perfect vision. There have been few attempts and no universal framework for measuring image quality loss due to visual impairments. The paper presents initia...

Purpose To determine the influence on the contrast sensitivity when the stimulus contains a fixation target in two retinal locations, foveal and parafoveal. Methods Four young adults with 0.0 logMar acuity participated in this study. The stimulus was based on vertical sinusoidal gratings masked by a circular (for foveal area) or a ring (for parafov...

Purpose. To determine eye symptoms in a population of university students with the use of video display units (VDU; TV, computers, laptops, smartphones and tablets). Methods. University students of three Universities (Universitat de Valencia, Univeristà degli Studi di Milano y Università Degli Studi di Milano-Bicocca) between 19 and 30 years of age...

Aim: To develop a Spanish version of an English questionnaire about eye symptoms in video display unit (VDU) users. Methods: We translated from English to Spanish the questionnaire developed by Hayes el al., following the WHO translation guidelines. Participants were university employees (teachers, technical and office workers) of the University o...

Aim: To evaluate the prevalence of eye symptoms in a non-presbyopic population of video display unit (VDU) users with flat-panel displays. Methods: One hundred and sixteen VDU users with flat-panel display from an urban population participated in the study; their ages ranging from 20 to 34y. There were 60 females and 56 males. An eye examination...

Tradicionalmente, la historieta ha sido considerada como una forma cultural?menor de vocaci?n infantil, por lo que su estudio hab?a sido soslayado en los estudios?hist?ricos hasta la reivindicaci?n que diferentes investigadores comenzaron?a hacer de la importancia historiogr?fica de la historieta tanto como referente?gr?fico como recurso de an?lisi...

To evaluate the effect of pupil size on image quality of a sectorial multifocal intraocular lens (IOL), the Lentis Mplus (Oculentis GmbH, Berlin, Germany), and the Acri.LISA IOL (Carl Zeiss Meditec, Jena, Germany). The authors measured the MTFs of the Lentis Mplus LS-312 IOL and the Acri.LISA 366D IOL with three different sizes of pupil diameters:...

Micharmut: Más allá de la vanguardia

This study presents a method for measuring scattering in explanted intraocular lenses (IOLs). Currently, determining scattering in IOLs is usually performed by Scheimpflug cameras and the results are expressed in the units used by this apparatus. The method we propose uses a spectrophotometer and this makes it possible to measure the total transmis...

Diabetes mellitus is a metabolic disorder characterized by the presence of chronic hyperglycaemia. Several structural, morphological, and physiological changes in each of ocular component have been described in detail during the past decades. Due to these abnormalities, the diabetic patient undergoes a degradation of the retinal image by an increas...

La conocida como “Nueva Escuela Valenciana” fue un movimiento historietistico de gran proyeccion en los anos 80 que reunio a una serie de autores profundamente comprometidos con la renovacion formal del medio sin dejar de lado el respeto a la tradicion tebeistica que habia vivido el Pais Valenciano durante las decadas anteriores. Durante los anos d...

Film adaptation of comic books has been a constant throughout the last century in the two main comic markets of the world: France and the US. However, the generalization of these adaptations from the beginning of the 21st century, despite sharing certain common marketing elements, has been especially different in their approach: while the American...

Purpose: To compare the in vitro optical quality of multifocal apodized intraocular lenses (IOLs) at different focal points. Setting: University of Valencia, Valencia, Spain. Design: Experimental study. Methods: The Acrysof Restor +3.0 diopter (D) multifocal IOL with 2 main foci (bifocal IOL) and the Finevision multifocal IOL with 3 main foc...

Purpose: To evaluate the optical quality of the Visian Implantable Collamer Lens (ICL) for different powers and pupil diameters. Methods: Wavefront aberrations of the -3, -6, -9, -12 and -15 diopters (D) V4b ICLs were measured at 3- and 4.5-mm pupils. The root mean square (RMS) of total higher order aberrations (HOAs), trefoil, coma, tetrafoil,...

In spite of the importance of figures referred to published titles, or number of copies printed, which help to set publishing strategies and to really know the comic situation in Spain, there are no liable data. We are giving in this article, some enlightening data along with some explanations related to the evolution of the market from 2001 to 200...

Using keratometry, we characterized the corneal molding due to wear of daily disposable contact lenses and looked for a relationship between corneal radius variation and the lens material hydrogel and its hydration. Ninety-six subjects were fitted with either 1-Day Acuvue contact lenses (58% hydration) or New Day contact lenses (38% hydration). Res...

The prevalence of pterygium was studied in a Saharan population in 1322 subjects, with ages ranging from 6 to 80 years old. Pterygium was diagnosed in 238 subjects and classified using 3 parameters: invasion, extension, and thickness. Prevalence increased with age in both males and females. Statistically significant differences with regard to age a...

The purpose of the present work was to study the effect on visual performance of wearing disposable soft tinted contact lenses for cosmetic purposes. Parameters such as contrast sensitivity (Vistech 6000), colour vision (Farnsworth-Munsell 100-Hue colour test), visual fields (static Goldmann perimetry) and subjective vision (what the wearer feels w...

A new technique for analysing the optical quality of the human cornea is presented. Corneal maps are obtained through keratographies and then converted into phase maps. The propagated fields generated from this surface are plotted and studied. It is shown that any irregularity in the cornea affects the propagated field and the energy distribution a...

A new technique for analysing the optical quality of the human cornea is presented. Corneal maps are obtained through keratographies and then converted into phase maps. The propagated fields generated from this surface are plotted and studied. It is shown that any irregularity in the cornea affects the propagated field and the energy distribution a...

Methods to quantify trabecular orientation are crucial in order to assess the exact trajectory of trabeculae in anatomical and histological sections. Specific methods for evaluating trabecular orientation include the technique (Whitehouse, 1974), manual tracing of trabecular outlines on a digitising board (Whitehouse, 1980), textural analysis (Veen...

The aim of this study was to investigate the eye-hand and eye-foot visual reaction time among young soccer players and to compare those with non-soccer players in order to evaluate possible differences. A vision screening of 53 young male soccer players belonging to the Valencia Soccer Club was done. Soccer players were divided in three categories,...

In this work we have studied the influence of the gaze stabilizing movements of the eye on the quality of the retinal image of the human eye obtained by double pass methods. The results obtained agree with the expected differences between the coherent and incoherent behaviour of the optical system of the eye. The movements-free retinal image is obt...

In this work we have studied the influence of the gaze stabilizing movements of the eye on the quality of the retinal image of the human eye obtained by double pass methods. The results obtained agree with the expected differences between the coherent and incoherent behaviour of the optical system of the eye. The movements-free retinal image is obt...

The procedure to compute the subjective difference between two input images should be equivalent to a straightforward difference between their perceived versions, hence reliable subjective difference metrics must be founded on a proper perception model.For image distortion evaluation purposes, perception can be considered as a set of signal transfo...

The application of computer devices equipped with video monitors both in clinical practice and human vision research has become widespread. These devices offer great advantages over other traditional methodologies (such as printed tests) because they facilitate the variation of the experimental parameters or the design of new psychophysical experie...

Applications such as refractive surgery demand an objective appraisal of the retinal image quality. The modulation transfer function (MTF) provides that information when measured directly. Moreover, the MTF obtained using a simple and objective method such as that described in this paper allows the neural contrast sensitivity function (CSF) to be o...

In this work, we have applied the fractional Fourier transform to obtain the Fresnel diffraction patterns in a theoretical eye. The FRT approach to Fresnel diffraction is easily implemented in a Gullstrand-Emsley theoretical eye, and it allows us to obtain the retinal image and then to derive the modulation transfer function of the eye, which can b...

In this work, we have applied the fractional Fourier transform to obtain the Fresnel diffraction patterns in a theoretical eye. The FRT approach to Fresnel diffraction is easily implemented in a Gullstrand-Emsley theoretical eye, and it allows us to obtain the retinal image and then to derive the modulation transfer function of the eye, which can b...

We have studied in this paper the effect of the screen area illuminated or number of pixels used (with pixel-ratio-unity) on two possible models which in practice are used for producing and predicting colours specified by their coordinates (x, y, L). The first model provides the mixtures through the response curves (luminance versus DAC values) of...

We investigate the visual performance associated with adaptation to a daily wear soft contact lens on the human eye. For this purpose, we used four parameters, one of which was an objective parameter, while the rest were subjective parameters. The objective parameter was a single quality parameter, a Merit function (Mf) derived from the modulation...

Measurement of corneal thickness has potential benefit both in the fitting of contact lenses and in monitoring any pathology that could affect corneal thickness. Corneal thickness measurement is undertaken using an accessory to the biomicroscope, the optical pachometer, or by means of expensive apparatus such as the ultrasonic pachometer. There are...

Les risques potentiels pour la santé liés à l'emploi d'écrans de visualisation sont une des préoccupations principales pour les millions de travailleurs qui s'en servent dans leurs activités professionnelles quotidiennes. Sur un groupe de 400 personnes non presbytes qui utilisaient des écrans, nous avons réalisé une étude à double objectif: 1) enqu...

Until now, subjective image distortion measures have partially used diverse empirical facts concerning human perception: non-linear perception of luminance, masking of the impairments by a highly textured surround, linear filtering by the threshold contrast frequency response of the visual system, and non-linear post-filtering amplitude corrections...

Lasers have been used in vision for measuring the neural contrast sensitivity function (CSF) by forming interference fringes on the retina. We distinguish among three kinds of illumination with lasers: incoherent (without noise), Maxwellian or coherent (with coherent noise), and diffuse coherent (with speckle). The three have different characterist...

It is well known that the modulation transfer function (MTF) characterizes the optical quality of the eye. Recently, some objective techniques have been introduced in order to measure this function in vivo. These techniques could be employed to display the temporal fluctuations of the eye + compensation system and to isolate the effect of the compe...

In this investigation the quality of two types of optical correction, hydrogel contact lenses and ophthalmic lenses, was compared by measuring the modulation transfer function (MTF) of the correcting lens plus visual optics system using an objective method. A merit function was defined in order to allow the direct comparison between the optical per...

The optical quality of the tear film of the eye was tested by measuring the retinal image before and after the break-up time (BUT). An objective method was used based on the evaluation of the retinal image of a point test projected onto the fovea. The loss of an entire tear film would result in a decrease in the optical quality because of corneal i...

As evidenced by many physiological and psychophysical reports, the receptive fields of the first-stage set of mechanisms of the visual process fit to two-dimensional (2D) compactly supported harmonic functions. The application of this set of band-pass filter functions to the input signal implies that the visual system carries out some kind of conjo...

A fully perceptual oriented approach for codebook design in the vector quantisation of images for compression purposes is presented. The proposed algorithm not only exploits the usually considered dependence on frequency of the human eye but also makes use of the nonlinear behaviour of the visual system for suprathreshold contrasts. From experiment...

We show how contrast (C) affects the recognition of defocused letters. To do this, the maximum distance (threshold distance) at which a subject, with an induced refraction of -5.5 D, can recognize a letter was determined. Our results show that when C = 1, the recognition threshold distance is such that the ratio eta/xi, between the pseudoimage of t...

We studied the influence of color and accommodation on the contrast sensitivity function (CSF). At the same time, we measured the effect of axial chromatic aberration (ACA) on the CSF. The CSF's of two observers were determined using red, green, blue, and white light, at 5- and 0.5-m viewing distances. At 5 m the CSF's were measured with natural vi...