Editing Cathode-ray tube (section)

====Graticules====
Most oscilloscopes have a [[oscilloscope#Graticule|graticule]] as part of the visual display, to facilitate measurements. The graticule may be permanently marked inside the face of the CRT, or it may be a transparent external plate made of glass or [[acrylic glass|acrylic]] plastic. An internal graticule eliminates [[parallax error]], but cannot be changed to accommodate different types of measurements.<ref>{{cite book |author1= Bakshi, U. A. |author2= Godse, Atul P. |title= Electronic Devices And Circuits |publisher= Technical Publications |year= 2008 |page= 38 |url= https://books.google.com/books?id=uJaQML8-MggC&pg=PA38 |archive-url= https://web.archive.org/web/20201207015004/https://books.google.com/books?id=uJaQML8-MggC&pg=PA38 |url-status= dead |archive-date= 7 December 2020 |isbn= 978-81-8431-332-1 }}</ref> Oscilloscopes commonly provide a means for the graticule to be illuminated from the side, which improves its visibility.<ref>{{cite book |last= Hickman |first= Ian |title= Oscilloscopes: how to use them, how they work |publisher= Newnes |year= 2001 |page= 47 |url= https://books.google.com/books?id=O2oj04vbQqgC&pg=PA47 |isbn=978-0-7506-4757-1}}</ref>