Why has my laptop screen gone darker?

swingaloo

I have a HP laptop about 18 months old. 
During the last few hours I have noticed the screen is not as bright !!!!!! it should be.
Usually this darkening happens if the battery is running down and it needs plugging into the mains and the brightness comes back.
Today plugging it in makes no difference. I have gone into settings and the brightness is turned up full. I can still use it but its like looking at the screen through sunglasses.
Is there anything else I can check.

teaselMay

Might sound daft but have you tried turning the screen brightness down and then back up again?

It may be a software glitch that means it thinks it needs to be in energy saving mode. Rebooting is always worth a try.

Emmia

Do you have a button for a security /privacy screen (F2 with a symbol of a computer) that is lit up?

If it's lit, press it and your screen will brighten.

My HP laptop has this feature 

Mark_d

As well as brightness settings there might be 'night light' settings or power settings. Perhaps you're in power saving mode and manually need to switch this off

swingaloo

Emmia said:

Do you have a button for a security /privacy screen (F2 with a symbol of a computer) that is lit up?

If it's lit, press it and your screen will brighten.

My HP laptop has this feature 

Yes I have this, F2 takes the brightness down and F3 takes it up again. It is on full brightness.

I have just noticed that if I turn it up or down nothing changes. If I am in Settings and adjust the brightness bar up or down it stays the same.

DullGreyGuy

have you checked its not still in power saving mode? I know with some previous windoze machines it would stay in low power mode even when plugged in if the battery was still below the threashold for going into the mode. 

Presumably rebooted the machine? 

Does the screen have some form of adaptive adjustment? Mine changes both brightness and colour temp depending on the ambient lighting. 

Emmia

swingaloo said:

Emmia said:

Do you have a button for a security /privacy screen (F2 with a symbol of a computer) that is lit up?

If it's lit, press it and your screen will brighten.

My HP laptop has this feature 

Yes I have this, F2 takes the brightness down and F3 takes it up again. It is on full brightness.

I have just noticed that if I turn it up or down nothing changes. If I am in Settings and adjust the brightness bar up or down it stays the same.

On mine F2 is the privacy screen, F3 is to dim and F4 to brighten 

km1500

Probably a silly question but if plugging it in makes no difference are you sure your charger is working

swingaloo

Thank you all for the replies, rebooted and its ok now. 

RavingMad

swingaloo said:

Thank you all for the replies, rebooted and its ok now. 

You'd have thought that's one of the first things you'd tried before posting