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[foh-toh-kath-ohd] /ˌfoʊ toʊˈkæθ oʊd/
a cathode, typically of a cesium or sodium compound, having the property of emitting electrons when activated by light or other radiation.
1925-30; photo- + cathode Unabridged
Based on the Random House Dictionary, © Random House, Inc. 2015.
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Examples from the web for photocathode
  • photocathode tubes magnify existing light so you can explore the gloom in all its eerie, green-tinted glory.
  • The gap between the diamond window and the photocathode is typically some fraction of a millimeter.
  • The gun is made entirely of copper, except for the magnesium photocathode.
  • Accelerator photocathode technology must be advanced to meet the needs of fourth generation light sources.
British Dictionary definitions for photocathode


a cathode that undergoes or is used for photoemission
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition
© William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins
Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012
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Encyclopedia Article for photocathode

an element of a photoelectric cell (q.v.) that emits electrons when struck by light, making possible the flow of electric current through the device. A substance often used for photocathodes is a partially oxidized silver-cesium alloy.

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Encyclopedia Britannica, 2008. Encyclopedia Britannica Online.
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