Nexus 6 OLED strobing

[rabidz7]

Does the OLED in the Nexus 6 support strobing to eliminate motion blur?

 

[Mr_Coffee]

OLED displays do not have backlights, and thus do no support strobing backlights.

 

[Sancus]

It's possibly to strobe OLED for low persistence, the Oculus Rift does it. But there's really no reason to bother with this on a phone so I'm about 99.99% sure that the Nexus 6 doesn't.

 

[flod]

dunno about motorola phones but i doubt it as it would probably be marketed (and rightly so if they were to do it)

on my galaxy s5 there's actually pwm; i dont know the frequency but it's enough to be a little annoying when scrolling

 

[rabidz7]

But there's really no reason to bother with this on a phone

Yes there is. Strobing eliminates motion blur, which is amazing. Going from my PowerMac with a CRT to my Nexus 5 is pretty annoying because even scrolling a web page results in the degeneration of text to a blur.

 

[sharknice]

OLED displays do not have backlights, and thus do no support strobing backlights.

No one said anything about backlights. The pixels are the light source, so you simply strobe the pixels.

 

[Sancus]

Yes there is. Strobing eliminates motion blur, which is amazing. Going from my PowerMac with a CRT to my Nexus 5 is pretty annoying because even scrolling a web page results in the degeneration of text to a blur.

Most people are used to this from LCDs and don't really care, and you're also ignoring one of the major disadvantages of strobing which is MASSIVELY reduced brightness - really unacceptable for a phone since they're rarely used in absolute darkness and frequently used in brightly lit places or outdoors.

Trying to turn strobing on and off depending on brightness requirements would be really awkward as well and produce a very poor user experience due to the huge brightness jump between the two. Many people think autobrightness is poor and annoying now...

It just wouldn't work very well. Current display tech doesn't have enough brightness to make strobing work outside of highly controlled lighting scenarios.

 

[flod]

you can ramp smoothly from full persistence to strobing by controlling the duty cycle on oleds

it would work very well on oleds in indoor settings where something like 100nits is acceptable, the persistence would be around 3ms which is a massive improvement from what we're used to.

the main problem is 60hz flicker though.

 

[elvn]

I think it's generally called screen blanking, where strobing is usually mentioned when describing turning the backlight on and off. Semantics maybe.

From what I've read, the oculus rift team is shooting for 90hz oled with screen blanking and their in house one might be that already (not the dev kits).
They consider blur elimination crucial to VR.

web-cyb.org oculus-rift_ces-interview-transcript

low persistence is a breakthrough. In that it was unexpected..it was, we did not expect to see the kind of jump in quality that we saw - where we said this isn't just one of those "every little bit helps" , it is a killer - it completely changes the way that, it completely changes the experience.. fundamentally."

 

[sharknice]

I think it's generally called screen blanking, where strobing is usually mentioned when describing turning the backlight on and off. Semantics maybe.

From what I've read, the oculus rift team is shooting for 90hz oled with screen blanking and their in house one might be that already (not the dev kits).
They consider blur elimination crucial to VR.

web-cyb.org oculus-rift_ces-interview-transcript

They are actually different things but both significantly reduce the perceived motion blur. The way the Occulus does it is by displaying each pixel for X ms as it is scanned in which works just like a CRT would.
The way strobing would work is every pixel is displayed simultaneously for X ms.

I'm not sure what would be better. I think that strobing the entire screen would look a bit smoother but I've never seen a display capable of doing both to compare them.

 

[EdZ]

The way the Occulus does it is by displaying each pixel for X ms as it is scanned in which works just like a CRT would.
The way strobing would work is every pixel is displayed simultaneously for X ms

The DK2 (and the Note 4 when used with Gear VR) do not scan out line-by-line. They have about 5 discrete segments that are (within a segment) output simultaneously.

 

[defaultluser]

I'm confused here.

I know why strobing the LCD backlight results in lower blur - it makes the changing pixels invisible for the portion of the frame that they are changing, and then lights them for a short period of time after they should be done switching. It takes advantage of the much faster, and much more regular switching times of the backlight from on-off

This is also why the CRT feels smoother with lower persistence and higher refresh: the pixel persistence is independent from the energy generated by the electron gun, so making a display that decays faster typically makes each frame stand-out (when compared to say, high-persistence displays like televisions). But it also means you have to drive them faster, or you'll see flicker.

I can't fathom how strobing of the AMOLEDs would improve blur perception. When the pixels combine all aspects: light/energy/color, you would think that the combination of (1) FAR sub ms response times for AMOLED and (2) same approximate time to turn the things on/off as to change color, would result in no improvement from strobing?

I could see a benefit from updating display-at-once versus blocks or lines, but that's a lot of bandwidth (or would require a local memory to store the frame buffer, and the user to deal with more latency). But is there really that much blur from AMOLED that the difference would be perceptible?

 

[rabidz7]

I'm confused here.

I know why strobing the LCD backlight results in lower blur - it makes the changing pixels invisible for the portion of the frame that they are changing, and then lights them for a short period of time after they should be done switching. It takes advantage of the much faster, and much more regular switching times of the backlight from on-off

This is also why the CRT feels smoother with lower persistence and higher refresh: the pixel persistence is independent from the energy generated by the electron gun, so making a display that decays faster typically makes each frame stand-out (when compared to say, high-persistence displays like televisions). But it also means you have to drive them faster, or you'll see flicker.

I can't fathom how strobing of the AMOLEDs would improve blur perception. When the pixels combine all aspects: light/energy/color, you would think that the combination of (1) FAR sub ms response times for AMOLED and (2) same approximate time to turn the things on/off as to change color, would result in no improvement from strobing?

I could see a benefit from updating display-at-once versus blocks or lines, but that's a lot of bandwidth (or would require a local memory to store the frame buffer, and the user to deal with more latency). But is there really that much blur from AMOLED that the difference would be perceptible?

Because motion blur can be caused by post-and-hold, not just response time. For something to be free of motion blur, each frame can only be held for a very short time.

 

[defaultluser]

Because motion blur can be caused by post-and-hold, not just response time. For something to be free of motion blur, each frame can only be held for a very short time.

EDIT. Never mind, did some more research, seems there's a continuation of sample and hold on a display tech capable of scanning is the cause.