{"id":1618,"date":"2011-08-24T20:08:36","date_gmt":"2011-08-24T20:08:36","guid":{"rendered":"http:\/\/www.joswassink.nl\/insight\/?p=1618"},"modified":"2011-08-24T20:08:36","modified_gmt":"2011-08-24T20:08:36","slug":"student-shrinks-electron-microscope","status":"publish","type":"post","link":"https:\/\/www.joswassink.nl\/insight\/?p=1618","title":{"rendered":"Student shrinks electron microscope"},"content":{"rendered":"<div id=\"attachment_1619\" style=\"width: 310px\" class=\"wp-caption alignleft\"><a rel=\"attachment wp-att-1619\" href=\"http:\/\/www.joswassink.nl\/insight\/?attachment_id=1619\"><img loading=\"lazy\" decoding=\"async\" aria-describedby=\"caption-attachment-1619\" class=\"size-thumbnail wp-image-1619\" title=\"scienceelectronmicroscope_dsc2609bewtvd_548x364\" src=\"http:\/\/www.joswassink.nl\/insight\/wp-content\/uploads\/scienceelectronmicroscope_dsc2609bewtvd_548x364-300x199.jpg\" alt=\"\" width=\"300\" height=\"199\" \/><\/a><p id=\"caption-attachment-1619\" class=\"wp-caption-text\">Leon inspects his microscope - Photo: Tomas van Dijk<\/p><\/div>\n<p><strong>Physics student Leon van Kouwen built a 10-centimetre working prototype of an electron microscope as his graduation project.<\/strong><\/p>\n<p>Typically the beam of an electron microscope is formed within a long  tube &#8211; up to several meters long. Inside, sets of condensers focus the  powerful beam through carefully crafted magnetic fields onto a specimen  under study. \u201cMagnetic or electric fields can focus electrons just like  lenses do with light,\u201d says charged particle optics expert Professor  Pieter Kruit (Applied Sciences). Electron beam manufacturer CRT, based  in Heerlen, contacted Kruit with a request to develop a low-tech  electron beam. CRT\u2019s executive director, Paul Aerssens, MSc explains  they were looking for another market for their expertise in electron  beam manufacture, since most displays have become flat screens.<!--more--><\/p>\n<p>However, the electron beam in a TV tube is very different from that  in an electron microscope. Generally, the electron source in a TV tube  is less powerful, and the energy variation between electrons is larger.  Both factors contribute to a less-focussed beam.<\/p>\n<p>Kruit holds up a tiny aluminium box the size of a cigarette butt with  three holes in it: the electron gun from a small colour TV. It  illustrates the cheap technology common in cathode ray tubes &#8211;  prefabricated metal parts put into a mould and stuck together by strips  of molten glass.<\/p>\n<p>Kruit appreciated the challenge and asked fellow student, Leon van<br \/>\nKouwen, to design, build and test a small electron microscope equipped with electrostatic focussing.<\/p>\n<p>In the lab, it\u2019s hard to believe this is a miniature microscope.  Large vacuum vessels, a rattling pump, several high-voltage supplies and  amplifiers occupy several tables. What it\u2019s all about however is the  small cylinder behind the glass. This is a functioning miniature  electron microscope with a resolution of about 30-50 nanometers. But Van  Kouwen cannot be sure, since the image is shaken up too much by the  vibrations of the vacuum pump.<\/p>\n<p>\u201cWe\u2019ve shown that the concept is feasible,\u201d says Kruit, \u201cand we\u2019ll  publish that in a scientific journal.\u201d CRT can now develop and build  cheap mini EMs and deliver them to the Berlin-based firm, SPECS GmbH,  which would like to include such devices in their equipment for surface  inspection on the nanoscale.<br \/>\n<em>Leon van Kouwen, \u2018Miniaturized SEM based on CRT technology\u2019, Thursday 25 August 2011<\/em><\/p>\n","protected":false},"excerpt":{"rendered":"<p>Physics student Leon van Kouwen built a 10-centimetre working prototype of an electron microscope as his graduation project.<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[3,6],"tags":[79,151,337],"class_list":["post-1618","post","type-post","status-publish","format-standard","hentry","category-articles","category-delta","tag-cathode-ray-tube","tag-electron-microscope","tag-pieter-kruit"],"_links":{"self":[{"href":"https:\/\/www.joswassink.nl\/insight\/index.php?rest_route=\/wp\/v2\/posts\/1618","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.joswassink.nl\/insight\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.joswassink.nl\/insight\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.joswassink.nl\/insight\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.joswassink.nl\/insight\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=1618"}],"version-history":[{"count":0,"href":"https:\/\/www.joswassink.nl\/insight\/index.php?rest_route=\/wp\/v2\/posts\/1618\/revisions"}],"wp:attachment":[{"href":"https:\/\/www.joswassink.nl\/insight\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=1618"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.joswassink.nl\/insight\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=1618"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.joswassink.nl\/insight\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=1618"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}