Airbus A319, A320 or A321. - Fringes observed on airbus <a href="//commons.wikimedia.org/wiki/Airbus" title="Airbus">Airbus</a> windshield due to <a href="//commons.wikimedia.org/w/index.php?title=Thin_film_interference&amp;action=edit&amp;redlink=1" class="new" title="Thin film interference (page does not exist)">thin film interference</a> caused by a conductive Indium Tin Oxide (ITO) thin film deposited on the window for electrical defrosting/defogging. The fringes are strongly visible because the thin film thickness is highly non-uniform on purpose: as the voltage is applied on two opposite points of the window, a uniform conductive film (uniform sheet resistance) would lead to non-uniform current density, and non-uniform defrosting. Some window parts, especially on the sides and far from the electrical contacts, would dissipate less heat, and defrosting would be significantly less efficient here. The ITO thickness pattern is cleverly designed to provide a rather uniform heat dissipation over the whole window. (description courtesy of <a href="//commons.wikimedia.org/w/index.php?title=88.164.16.51&amp;action=edit&amp;redlink=1" class="new" title="88.164.16.51 (page does not exist)">88.164.16.51</a>). The photo was taken through the gate glass-wall, without any polarizing filter on the camera.
<a href="//commons.wikimedia.org/wiki/User:Etan_J._Tal" title="User:Etan J. Tal">Etan J. Tal</a>
<span class="int-own-work" lang="en">Own work</span>