Physics of Vision
This research area explores how the physical properties of light interact with the visual system to create visual perception. Topics of interest are the nature of light, the optics of the eye, phototransduction at the retinal level, and the subsequent processing of visual signals in the brain. This field also includes the development of advanced optometric and diagnostic technologies for the evaluation of refractive errors and visual function.
Staff
Associate Professors: Filippo Pisano, Gianluca Ruffato
Post-doc
Chiara Guidolin
PhD students
Anna Roccafore
External collaborators
Dominga Ortolan (DFA), Renzo Colombo (DFA), Pietro Gheller (DFA), Anto Rossetti (DFA), Mirko Chinellato (DFA), Marino Formenti (DFA), Luca Battaglini (Dipartimento di Psicologia Generale).
Research activities
Entoptic phenomena
Entoptic phenomena are visual artifacts that originate directly inside the eye as a consequence of the interaction of light with the anatomical structure. Among the most known are floaters, moving shadows on the retina produced by natural inhomogeneity present in the vitreous. Haidinger's brushes are perhaps the most interesting entoptic phenomenon from a clinical point of view. They consist in the perception of a particular pattern in the presence of polarized light and are produced by the filtering action of the radial structure of the cone axons in correspondence of the fovea (Henle's fibres). Since the correct perception of the phenomenon is related to a normal density and distribution of macular pigments, the perception of Haidinger's brushes has been identified as an effective marker for the screening for maculopathy and other diseases of the macula. Research in this area focuses on the development and testing of prototype tools for investigating the phenomenon with applications in the field of clinical screening.
Contacts: Gianluca Ruffato
Colour perception
Colour perception. Colour perception is the process by which visual information carried by different wavelengths of visible light is interpreted. This occurs thanks to the single or combined stimulation of three different types of photoreceptors in the retina, the cones, sensitive to different regions of the spectrum with peaks close to the colours red, green, and blue. The process of integrating and processing signals, at the retinal and cortical levels, is complex, and there are several physical parameters that are involved in the construction of the visual percept, for example intensity, duration, or spectrum of the light stimulus. Research in this area focuses on the temporal dynamics of colour perception as various physical parameters of the light stimulus vary, through the development of models and dedicated experimental setups. This area also includes the analysis of the properties and effects on vision of optical filtering elements, for example coloured contact lenses or ophthalmic lenses, used for professional, medical, or sporting purposes.
Contacts: Gianluca Ruffato
Physical methods and techniques for optometry
In the field of research, optometry is making significant progress through the innovation and development of new diagnostic and therapeutic methods. That involves the introduction of new instruments and techniques for measuring visual functionality, the integration of new technologies such as artificial intelligence systems, and the development of new treatments, such as ophthalmic or contact lenses for the control of myopic progression. In this research area, the activities concern for instance the analysis of new treatments, the comparison between different measurement techniques, the prototyping of new instrumentation, and the study of correlations in multifactorial processes.
Contacts: Renzo Colombo
The retina as a window to the brain
The retina is an accessible part of the central nervous system (CNS) that forms functional and physiological connections with deeper brain regions and plays a crucial role in sensory perception, through a mesmerizing arrangement of specialized neural cell types. As CNS pathologies are often reflected in eye-specific characteristics, observing the retina offers a unique opportunity for non-invasive assessment of brain health in less accessible areas. This research activity aims to develop optical methods to measure functional and biomolecular signals in the retina using non-invasive approaches compatible with point-of-care settings.
Contatti: Filippo Pisano
