<?xml version="1.0" encoding="utf-8"?><mads xmlns="http://www.loc.gov/mads/" xmlns:mods="http://www.loc.gov/mods/v3" xmlns:xlink="http://www.w3.org/1999/xlink" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://www.loc.gov/mads/
mads.xsd"><authority><topic authority="http://AATesaurus.cultura.gencat.cat/aat/getty_en">x-ray optics</topic></authority><related type="narrower"><topic>polycapillary optics</topic></related><related type="broader"><topic>optics</topic></related><variant type="other"><topic>optics, x-ray</topic></variant> <note xml:lang="en"><![CDATA[ Branch of optics that uses x-rays instead of visible light, concerned with focusing and otherwise manipulating x-rays beams for use in analysis. Since x-rays are strongly absorbed by solid matter, the optics used in the visible and near-infrared portions of the electromagnetic spectrum cannot be used to focus or reflect the radiation. ]]></note></mads>