Extron electronic VS 200 SL user manual Introduction, Example of Phosphor Burn, 1Chapter One

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.

Electron beam	Light
	output

Phosphor screen

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.

VS 200 SL User's Manual

1Chapter One

Introduction

Description of VideoShift

Features

Specifications

ii Extron • VS 200 SL • User’s Manual