ECDL 
Module 1 Workbook 3 12. Light Pen 
A light pen is a hand held input device which looks similar to a small pen or wand.
It is connected to a computer monitor and allows the user to both point to objects and to draw on the screen.
It works because the monitor contains a light sensitive detector which picks up light emitted from the pen and calculates its position on the screen.
Challenge see if you can find out one extra fact on this topic that we haven't already told you
Click on this link: Light Pen
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