Descripción
**Hora de inicio:** 12:00. **Hora de fin:** 13:00.
he eye, despite being extraordinarily well-developed through evolution, is not an ideal optical system and produces retinal images of moderate quality. On the other hand, simple, textbook comparison of the eye to a man-built optical instrument, such as a camera, for example, is totally unjust. The eye is a complicated, dynamic and robust optical system. The image of a distant object needs to travel through a thin few micrometers thick layer of tear film, cornea, aqueous humour, pupil, crystalline lens with a gradient refractive index, before it falls on the photosensitive retina at the back of the eye. All of the eye elements, which the rays that form the image of a distant object pass, are dynamic in nature and are not fully synchronized with each other.
All of the eye’s elements together with signals associated with accommodation, pupillary response, and those of cardio-pulmonary system lead to a static retinal image that is far from ideal at a given point of time. However, due to the dynamic nature of all those elements, the human eye is able to resolve images with high acuity of about one minute of arc mainly because of the match between moderate optical image quality and the resolution of the retinal mosaic. The actual image that a human being can resolve also depends on neural processes occurring in the retina and the brain. Those could involve elements of stochastic resonance where the naturally occurring eye vibrations may result in an improved visual quality.
Some aspects of the dynamics in optical characteristics of the eye, particularly those related to changes in the tear film structure and microfluctuations of the steady-state accommodation, have been considered. The latter can be associated with the refractive status of the eye from which emmetropization mechanisms (i.e., processes that optimize the eye’s optics) could be learnt. However, the wealth of information available when examining the dynamic nature of optical characteristics of the eye has not been fully exploited. Challenges exist to develop analytic methodologies that would adequately account for all such variations and their interdependencies with the major physiological signals of the human body. To achieve this goal, an overall system of the eye’s optics that takes into account the aberration dynamics needs to be considered.
The talk will summarize recent endeavors undertaken in search of adequate characterization of the dynamics encountered in human eye’s optics.