On Monday, 25.III.2019 at 4.30 p.m. in room 0.03, the Jerzy Pniewski and Leopold Infeld Colloquium of the Faculty of Physics will be held. Our guest will be PROF. ROBERT ISKANDER from Wrocław University of Technology in Wrocław.

The invited lecturer is a specialist in biomedical signal processing, optics of vision and operation of the human eye, as well as the construction of optometric and ophthalmic instrumentation (he is the author of several patents in this field). For a large part of his professional work he was associated with Queensland University of Technology in Australia. Since 2011 he has been working at the Wrocław University of Technology, where he heads the Biomedical Signal Processing Team.

Prof. Iskander will give a lecture entitled:
,,PHYSICS OF THE HUMAN EYE IN THE 21ST CENTURY''

Before the seminar, from 4 p.m., informal discussions on coffee and cakes in the lobby in front of room 0.03.

Lecture summary:
The human eye is not a static system, but a complicated, dynamic optical system in which we observe temporal changes of wavefront aberration caused by microfluctuations of the accommodation, pulsation of the eye or temporal changes of eye surface characteristics (e.g., tear film dynamics, corneal deformations). Despite the observed dynamics, the current correction of eyesight (with glasses, contact lenses, or refractive surgery) is static. Until we can apply dynamic vision correction outside laboratories, the dynamics of the human eye optics must be well understood to objectively determine the optimal static correction. That is why research on the dynamics of wavefront aberration in the human eye is important. On the other hand, it is worth considering whether a perfectly corrected optical system of the eye, for example, using adaptive optics, will be the best solution in the visual process. It is over 50 years that have passed since the work of Lohmann and Paris, who studied the effect of longitudinal vibrations in the ideal optical system (periodic changes of the position of the image with respect to the focus). Interestingly, they found that the integrated quality of an image placed outside the focus increases in the presence of a defocus vibration. The presence of such a mechanism in the eye has been speculated for years by the speaker. We have recently demonstrated experimentally that both simulated retinal image quality and experimentally measured visual acuity improve when defocus vibrations are added to an emmetropic eye. The seminar will end with an open, debatable question: does the small defocus naturally occurring in the eye contribute to better vision?