Unpacking the Science Behind Fluorescent Light Tubes

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Mercury vapor in fluorescent light tubes is maintained at low pressure to enhance the efficiency of light production through gas discharge. When electricity excites the mercury vapor, it generates ultraviolet light, which is not visible to the human eye. The inner coating of phosphor converts this ultraviolet light into visible light, making the lamp functional for illumination. This combination of low pressure and phosphor coating is crucial for the lamp's brightness and energy efficiency. Understanding these principles is essential for grasping how fluorescent lighting operates effectively.
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could anyone explain why the mercury vapour inside a fluorescent light tube is kept at a low pressure and the purpose of the coating on the inside of the tube?

thanks
marco
 
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marco123 said:
could anyone explain why the mercury vapour inside a fluorescent light tube is kept at a low pressure and the purpose of the coating on the inside of the tube?

thanks
marco

Wikipedia said:
A fluorescent lamp or fluorescent tube is a gas-discharge lamp that uses electricity to excite mercury vapor. The excited mercury atoms produce short-wave ultraviolet light that then causes a phosphor to fluoresce, producing visible light.
http://en.wikipedia.org/wiki/Fluorescent_lamp

See also: http://en.wikipedia.org/wiki/Fluorescent_lamp#Principles_of_operation
 
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thanks for that! ;)
 
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