Laptop backlights are LED, but contain mercury?

Factual Questions
1

This one was a bit confusing to me - (Dell Latitude E5450, for what it’s worth) - apparently laptop screen backlights are LEDs these days, but LEDs don’t contain mercury - but there are warnings online about laptop backlights containing mercury? Did they used to be illuminated by small flourescent lamps or something?

And the LCD screens themselves don’t have mercury?

2

Yes. From Wikipedia:
"The light source can be made up of:

[ul]
[li]Light-emitting diodes (LEDs)[/li][li]An electroluminescent panel (ELP)[/li][li]Cold cathode fluorescent lamps (CCFLs)[/li][li]Hot cathode fluorescent lamps (HCFLs)[/li][li]External electrode fluorescent lamps (EEFLs)[/li][li]Formerly, incandescent lightbulbs[/li][/ul]"

3

OK, thanks. But out of all these, only fluorescent lamps contain mercury?

4

Correct.