Extron VS 200 SL Users ManualExtron VS 200 SL Users Manual
1
Chapter OneIntroduction

Description of VideoShift

Features

Specifications

VS 200 SL User's Manual

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Phosphor
screen
Electron beam Light
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Background Information
__ Terms that relate to this manual
Burn/Burn-in Overexposure - In the case of CRTs, when the screen's
phosphor has been exposed to the electron beam for too long a
time, the phosphor becomes permanently damaged. The
damaged phosphor has a different color; that's why the image
appears to remain on the screen when the beam is off.
CRT (cathode ray tube) Sometimes called a "picture tube", a CRT is a
vacuum tube that produces light when energized by the electron
beam inside the tube. The light beam strikes a phosphor coating
on the back side of the screen, causing it to glow.
Phosphor – The chemical coating on the inside of a CRT screen that emits
light when struck by the electron scan beam.
Screen Saver – Any method of "saving" the CRT screen from phosphor burn
by changing the displayed image or by blanking the screen.

Example of Phosphor Burn

If the text on the top screen were to stay
too long, it could damage the phosphor
on the screen.
As shown on the second screen, when
the text does change, there are images
of the old text burned into the phosphor,
making it difficult to read the new text.