Kaiser-Bessel derived (KBD) window
<a href="//commons.wikimedia.org/wiki/User:RetoGalli" title="User:RetoGalli">RetoGalli</a>
2008-02-29, revised 2019-03-21 by <a href="//commons.wikimedia.org/wiki/User:Bob_K" title="User:Bob K">Bob K</a>
<span class="int-own-work" lang="en">Own work</span>