1 second delay in screen wake?

[Cheewii Poon]

Having a one second screen delay between pressing the power button and your phone actually waking to show the lockscreen?

I've always had this problem with my Lumia 720, and Nokia didn't acknowledge this was a problem, and several people have reported this issue occurring after updating to GDR3. I've gotten used to it by now, pressing the power button as I take my phone out of my pocket so it wakes on time. However I only now realised (sort of) that when you press the power button and for the one second the screen stays off, the phone's proximity sensor turns on, and only after it turns off does the screen start fading in and waking. I'm not sure if this is the case on other phones, but on my Lumia 720 there is a tiny tiny red LED that resides in the proximity sensor and lights up very faintly when the proximity sensor is on. You will see that it is on when you are on a call so your phone will turn off the screen while your phone is pressed on your ear.

So tldr the reason why there might be a delay in your screen waking is because the phone is checking it's proximity to something before deciding to turn on. Still haven't figured out what it's actually detecting for and why though. One possibility is that it's for the Glance screen, but that doesn't make sense because 1) I don't have the Glance Screen switched on on my Lumia 720 and 2) The Glance screen activates without you having to press the power button.

Anyone have any similar discoveries?

 

[WanderingTraveler]

I was about to say that, lol.

Now, Nokia does not acknowledge this because they treat the Update 3 Dev Preview as a non-official firmware.
The warranty is voided should something not approved by Nokia be flashed onto the phone.

For it to be normal, it should be in the range of roughly half a second, as that's the time it takes for my 620's screen to turn on.

 

[travis_valkyrie]

Put the phone under a poor camera enabled device (Surface RT or any device with a camera that can see IR light - appears violet). Wake up the phone and you should see the proximity sensor light up for about half a second. Put your finger over it without touching, say like 2mm and you should see the screen to it's max brightness. In my findings, I think it's not just the proximity sensor that turns on upon wake.