|The liquid crystal pixels in the display do not produce light - they let through the white light or modify (color) or block (black out) that white light that is being produced by a light source behind the liquid crystal pixels.|
The back of the display assembly is constructed such that the white light source has it's light evenly distributed behind the liquid crystal pixels - for conventional LCD displays , the CCFL(s) is(are) not directly behing the liquid crystal pixel grid - there are reflectors back there - I don't know whether that applies to LED LCD displays too.
The biggest advantage of an LED LCD display - which uses LEDs as the white light source behind the liquid crystal pixels - is, in theory, the LEDs have a MUCH longer useful life.
For that matter, I don't recall ANY led on a computer that has EVER burnt out.
CCFLs will burn out eventually, the same as any other florescent lamp (tube).
We get Topics here constantly about conventional LCD displays - LCD displays that have one or more CCFL(s) - producing an overall tint, or the display going very dim, or there being no display at all (blackness). If the laptop or monitor has not been subjected to a physical jolt, usually that's caused by the CCFL(s) being in the process of failing or having failed completely, not by the voltage inverter for it(them) malfuctioning or failing.