3 ms·

Well, isn't it an aspect of persistence? This is usually called ghosting, and can be combated using "overdrive"; https://blurbusters.com/faq/oled-motion-blur/

Well, isn't it an aspect of persistence? This is usually called ghosting, and can be combated using "overdrive"; https://blurbusters.com/faq/oled-motion-blur/ https://blurbusters.com/faq/oled-motion-blur/ https://blurbusters.com/faq/lcd-overdrive-artifacts/ https://blurbusters.com/faq/lcd-overdrive-artifacts/ Edit: regarding my older comment, I thought that QLED were quantum dots mounted on individual LEDs. They are regular LCDs, with quantum dots providing the colour conversion. That makes more sense from an economical perspective, less so for performance. Maybe OLED and QLED could be combined to leverage the best OLED for all colors?

dan-robertson 6y ago
If you draw a graph of the signal going into a monitor (above) vs the luminosity of a pixel, it might look like this for a crt: ^ | _______________ | / | | | | |_/ |_________________> t ^ | /\ | / \ | | \ | | \ | | `-._ |____/__________`-.___>t And the luminosity like this for an lcd: ^ | _________ | .’ | / | / | / |______-’______________>t Persistence is the time it takes between when the luminosity goes up and when it goes down. It is low for CRTs and high for LCDs (which stay on until they need to switch unless the monitor is low persistence (or low persistence is emulated with a high refresh rate and black frame insertion). The switching time is the time between when the signal starts (or rather when the monitor has finished working out what the signal means and has started trying to change the luminosity) and when it gets bright (or in the case of LCDs, to the right luminosity). Ghosting comes from not switching strongly enough and overdrive (switching too hard) tends to lead to poor colour accuracy.
- ric2b 6y ago
  Those charts are awesome, props for the creativity.
- MayeulC 6y ago
  Nice charts, did you draw them by hand? You are right. That directly contributes to latency. This effect is called pixel response time [1], and is usually measured "grey-to-grey" [2]. Nowadays, though, I think monitors usually have a short response time (<1ms for "gamer" monitors). > Persistence is the time it takes between when the luminosity goes up and when it goes down Right. But that proves the two are somewhat linked, especially as pixel response isn't symmetric (0->1 and 1->0). Reading a bit more into it, the industry terms for persistence seem to be both grey-to-grey (GtG), and Moving Picture Response Time (MPRT). The latter is a measurement method [3] for perceived motion blur. It directly depends on the time each pixel remains lit with the same value ("persistence" strikes again), so a slow (>1 frame) or incomplete transition can create motion blur (contributes to persistence). > low persistence is emulated with a high refresh rate and black frame insertion It can also be achieved wit backlight strobing on backlit displays: strobing for 1ms on a "full-persistence" (pixel always on) display gives a 1ms persistence regardless of the frame rate. A ~1000 FPS display would be necessary to get the same level of persistence with black frame insertion alone. I believe this is part of the reason Valve went with an LCD instead of an OLED screen to get the 0.33ms persistence on the Index HMD. [1] https://blurbusters.com/gtg-versus-mprt-frequently-asked-questions-about-display-pixel-response/ https://blurbusters.com/gtg-versus-mprt-frequently-asked-que... [2] (from the above) https://hal.archives-ouvertes.fr/hal-00177263/document https://hal.archives-ouvertes.fr/hal-00177263/document [3] (also from blurbusters article) https://lcd.creol.ucf.edu/Publications/2017/JAP%20121-023108.pdf https://lcd.creol.ucf.edu/Publications/2017/JAP%20121-023108...

dan-robertson 6y ago

If you draw a graph of the signal going into a monitor (above) vs the luminosity of a pixel, it might look like this for a crt: ^ | _______________ | / | | | | |_/ |_________________> t ^ | /\ | / \ | | \ | | \ | | `-._ |____/__________`-.___>t And the luminosity like this for an lcd: ^ | _________ | .’ | / | / | / |______-’______________>t Persistence is the time it takes between when the luminosity goes up and when it goes down. It is low for CRTs and high for LCDs (which stay on until they need to switch unless the monitor is low persistence (or low persistence is emulated with a high refresh rate and black frame insertion). The switching time is the time between when the signal starts (or rather when the monitor has finished working out what the signal means and has started trying to change the luminosity) and when it gets bright (or in the case of LCDs, to the right luminosity). Ghosting comes from not switching strongly enough and overdrive (switching too hard) tends to lead to poor colour accuracy.

ric2b 6y ago
Those charts are awesome, props for the creativity.
MayeulC 6y ago
Nice charts, did you draw them by hand? You are right. That directly contributes to latency. This effect is called pixel response time [1], and is usually measured "grey-to-grey" [2]. Nowadays, though, I think monitors usually have a short response time (<1ms for "gamer" monitors). > Persistence is the time it takes between when the luminosity goes up and when it goes down Right. But that proves the two are somewhat linked, especially as pixel response isn't symmetric (0->1 and 1->0). Reading a bit more into it, the industry terms for persistence seem to be both grey-to-grey (GtG), and Moving Picture Response Time (MPRT). The latter is a measurement method [3] for perceived motion blur. It directly depends on the time each pixel remains lit with the same value ("persistence" strikes again), so a slow (>1 frame) or incomplete transition can create motion blur (contributes to persistence). > low persistence is emulated with a high refresh rate and black frame insertion It can also be achieved wit backlight strobing on backlit displays: strobing for 1ms on a "full-persistence" (pixel always on) display gives a 1ms persistence regardless of the frame rate. A ~1000 FPS display would be necessary to get the same level of persistence with black frame insertion alone. I believe this is part of the reason Valve went with an LCD instead of an OLED screen to get the 0.33ms persistence on the Index HMD. [1] https://blurbusters.com/gtg-versus-mprt-frequently-asked-questions-about-display-pixel-response/ https://blurbusters.com/gtg-versus-mprt-frequently-asked-que... [2] (from the above) https://hal.archives-ouvertes.fr/hal-00177263/document https://hal.archives-ouvertes.fr/hal-00177263/document [3] (also from blurbusters article) https://lcd.creol.ucf.edu/Publications/2017/JAP%20121-023108.pdf https://lcd.creol.ucf.edu/Publications/2017/JAP%20121-023108...