1.0Universe of Instrumentationhttp://www.edisontc.org/uiadminhttp://www.edisontc.org/ui/author/admin/Phototube - Universe of Instrumentationrich600338<blockquote class="wp-embedded-content" data-secret="2K8Urv4ODW"><a href="http://www.edisontc.org/ui/home/course/unit-iii/phototube/">Phototube</a></blockquote><iframe sandbox="allow-scripts" security="restricted" src="http://www.edisontc.org/ui/home/course/unit-iii/phototube/embed/#?secret=2K8Urv4ODW" width="600" height="338" title="“Phototube” — Universe of Instrumentation" data-secret="2K8Urv4ODW" frameborder="0" marginwidth="0" marginheight="0" scrolling="no" class="wp-embedded-content"></iframe><script type="text/javascript">
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http://www.edisontc.org/ui/files/2016/02/Unit3Banner900.jpg800254The phototube works by having light strike the almost flat transparent end of the tube (the photocathode) (see the tube photo below). Electrons are ejected from the cathode and move through the tube to the anode at the other end. These simple photo sensors have been replaced by solid state devices. The phototube is related … Continue reading