iPhone 13 Pro iPhone 13 Pro: Screen PWM flicker at ALL brightness

[eret9616]

ipad pro 2020 12.9 = 58,820hz
ipad pro 2021 12.9 miniled = 19,190hz
macbook pro 16inch 2019 = 131,700hz


well.. 480hz and 240hz.. isnt that horrible



source:

2021 Apple 12.9-inch M1 iPad Pro with mini LED display shows poor display characteristics including reduced PWM and response times

We tested the PWM and display response times in our 2021 12.9-inch iPad Pro with M1 and found that there are some downsides to Apple's transition to mini LED tech this year. The 2021 12.9-inch iPad Pro not only shows lower PWM compared to the 2020 model but also has noticeably higher response...

www.notebookcheck.net

Apple MacBook Pro 16 2019 Laptop Review: A convincing Core i9-9880H and Radeon Pro 5500M powered multimedia laptop

Notebookcheck.com reviews the flagship model of the MacBook Pro 16, Apple's latest multimedia laptop. The machine comes with an AMD Radeon Pro 5500M GPU and an Intel Core i9-9880H CPU, along with 16 GB of DDR4-2666 RAM and a 1 TB SSD. Read on to find out why have awarded the MacBook Pro 16 top...

www.notebookcheck.net

 

[eret9616]

that is, because in person you can not see the flicker, of course. But you will feel it after a while if your eyes are sensitive. E.g. if you had laser surgery (which is increasingly popular to get rid of glasses)

I had LASEK 5 years ago, It did make my eye sensitive and prone to dry eye, Last year I upgrade to iphone 12 from iphone8 plus, my eye feels not very comfort, recent I realize maybe its because the pwm issue in OLED, my iphone12 mini, I tried switching to a iphone11 and my eye feels much better...

 

[happy orchard]

Just posted on another thread slo-mo videos I just recorded comparing 12PM and 13PM. I want to share with anyone who might find this helpful. This just might be amazing. Fingers crossed.



Thread: Eye-strain while using iPhone X



Posts: 3889-3891

 

[naituil9]

I need to use oled saver, an overlay ap

480hz looks like a pretty good value, and if it is fixed at all brightness levels I could really enjoy the display…
I had bad issues with iPhone XS, then I used Samsung s10+ (No issue), s20+ (light PWM effects), I’m using S21 Ultra (bad PWM issues, I need to use oled saver, an overlay app, to keep brightness up and have display dimmed by this app).
Frequency values are similar across all these devices, so I guess I’m sensitive to variations too, I bet it’s better to have PWM (a high level, hopefully) at all brightness instead of great fluctuations (in fact some time ago I think I read that Samsung used PWM at all levels, maybe they stopped after s10 lineup).
Fixed 480hz seems like great news for me, I hope to get more confirmations about that (I don’t understand the Russian video posted above, as I have no other reference values to compare)

Whoever says 480Hz PWM on iPhone 13 series is better/improved over 12 Pro is UTTERLY WRONG.

The negative impact of low-freq PWM doesn't only correlate with the frequency but also (as pointed out above) with pulsation coefficient and modulation. iPhone 13 Pro/Max is terrible at both for ALL brightness due to the nature of LPTO.

To dive a bit deeper, iPhone 12 Pro/Max uses DC-like dimming above 25% brightness so that even though there is still PWM, the pulsation coefficient and modulation (<20%) are within the safe range. Below 25% brightness yes it's terrible 240Hz but it can be overcome by setting higher brightness & reducing white points.

On the other hand, iPhone 13 Pro/Max uses 480Hz PWm at ALL brightness with modulation close to 100% so it's in the high risk zone following IEEE PAR 1789 guidelines for low risk (http://www.bio-licht.org/02_resources/info_ieee_2015_standards-1789.pdf) - Figure 18 on page 29.

(Testing video on a Chinese website, no need to read any text: https://is.gd/hLaKm7)

Supposedly iPhone 13/mini should use the same panel as 12 Pro/Max to benefit from the DC-like dimming but from test result - Nope to save cost Apple doesn't do it.

Unfortunately there is no way a user can do about it unlike iPhone 12 Pro/Max. For me personally I am going to return the iPhone 13 Pro which caused discomfort right after 10min of usage and keep my iPhone 12 Pro for the eye comfort (and probably lighter weight)

 

[trali]

with modulation close to 100%

Could you please prove it?

Based on measuring in this video:

Mod% in iPhone 13 Pro is (almost always) 16, sometimes it’s 30, but not 100.

From IEEE 1789 (for frequencies between 90 Hz and 1250 Hz):

Mod% < 0.08x(flicker frequency) for Low-Risk Level
and
Mod% < 0.0333x(flicker frequency) for NOEL (no observable effect level)

For 480 Hz we have:
Mod% should be < 38.4 for low-risk and
Mod% should be < 15.984 for NOEL

 

[jrajpaul]

Whoever says 480Hz PWM on iPhone 13 series is better/improved over 12 Pro is UTTERLY WRONG.

The negative impact of low-freq PWM doesn't only correlate with the frequency but also (as pointed out above) with pulsation coefficient and modulation. iPhone 13 Pro/Max is terrible at both for ALL brightness due to the nature of LPTO.

To dive a bit deeper, iPhone 12 Pro/Max uses DC-like dimming above 25% brightness so that even though there is still PWM, the pulsation coefficient and modulation (<20%) are within the safe range. Below 25% brightness yes it's terrible 240Hz but it can be overcome by setting higher brightness & reducing white points.

On the other hand, iPhone 13 Pro/Max uses 480Hz PWm at ALL brightness with modulation close to 100% so it's in the high risk zone following IEEE PAR 1789 guidelines for low risk (http://www.bio-licht.org/02_resources/info_ieee_2015_standards-1789.pdf) - Figure 18 on page 29.

(Testing video on a Chinese website, no need to read any text: https://is.gd/hLaKm7)

Supposedly iPhone 13/mini should use the same panel as 12 Pro/Max to benefit from the DC-like dimming but from test result - Nope to save cost Apple doesn't do it.

Unfortunately there is no way a user can do about it unlike iPhone 12 Pro/Max. For me personally I am going to return the iPhone 13 Pro which caused discomfort right after 10min of usage and keep my iPhone 12 Pro for the eye comfort (and probably lighter weight)

I think it’s user dependant. I can’t use the 12 pro / 12 pro max / 12 or 12 mini. All those screens cause nausea and migraine instantly.

 

[Mastrociambella]

Whoever says 480Hz PWM on iPhone 13 series is better/improved over 12 Pro is UTTERLY WRONG.

The negative impact of low-freq PWM doesn't only correlate with the frequency but also (as pointed out above) with pulsation coefficient and modulation. iPhone 13 Pro/Max is terrible at both for ALL brightness due to the nature of LPTO.

To dive a bit deeper, iPhone 12 Pro/Max uses DC-like dimming above 25% brightness so that even though there is still PWM, the pulsation coefficient and modulation (<20%) are within the safe range. Below 25% brightness yes it's terrible 240Hz but it can be overcome by setting higher brightness & reducing white points.

On the other hand, iPhone 13 Pro/Max uses 480Hz PWm at ALL brightness with modulation close to 100% so it's in the high risk zone following IEEE PAR 1789 guidelines for low risk (http://www.bio-licht.org/02_resources/info_ieee_2015_standards-1789.pdf) - Figure 18 on page 29.

(Testing video on a Chinese website, no need to read any text: https://is.gd/hLaKm7)

Supposedly iPhone 13/mini should use the same panel as 12 Pro/Max to benefit from the DC-like dimming but from test result - Nope to save cost Apple doesn't do it.

Unfortunately there is no way a user can do about it unlike iPhone 12 Pro/Max. For me personally I am going to return the iPhone 13 Pro which caused discomfort right after 10min of usage and keep my iPhone 12 Pro for the eye comfort (and probably lighter weight)

Do you happen to have pulsation and modulation values for iPhone XS, Samsung Galaxy S10+, S20+, S21 Ultra?
I’m still trying to figure out what really affects me, I could use only Samsung Galaxy S10+ without any discomfort, from the list above…

 

[naituil9]

Could you please prove it?

Based on measuring in this video:

Mod% in iPhone 13 Pro is (almost always) 16, sometimes it’s 30, but not 100.

From IEEE 1789 (for frequencies between 90 Hz and 1250 Hz):

Mod% < 0.08x(flicker frequency) for Low-Risk Level
and
Mod% < 0.0333x(flicker frequency) for NOEL (no observable effect level)

For 480 Hz we have:
Mod% should be < 38.4 for low-risk and
Mod% should be < 15.984 for NOEL

Good question! I think the confusion here is different metrics.

The video you quoted was measuring "Flicker Index" (or Pulsation Coefficient), which is a different metrics from Modulation (Mod %) / Flicker percentage, which IEEE 1789 was using along with frequency to determine risk level, just as you mentioned. They were not using "Flicker Index". Below are the definition taken from http://www.bio-licht.org/02_resources/info_ieee_2015_standards-1789.pdf:

Picture below is result from a meter that measures not only flicker index but also Mod %. Quick translation for you:

Frequency: 480.19 Hz
Modulation: 97.6 %
Percent Flicker: 95.29%
Flicker Index: 0.306 (Somewhat in line with the Russian folks' video, you see)
Risk alert: High Risk

What's worse is that OP mentioned this kind of high Mod % is detected at all brightness level, which as I mentioned earlier is probably a drawback of LTPO display technology. And to also cut cost on the lower end iPhone 13/mini model, Apple implemented the same PWM policy (480Hz, High Mod % at all brightness) on the entire line (even though in theory iPhone 13/mini could use the same as iPhone 12 Pro)

 

[Mr.Simple]

After one day with the 13 Pro Max i sadly must say that i again feel more eye strain and headache. It´s got better when i think last year with the 12 Pro Max or S21 Ultra but it seems not enough for me I will play with the reduced white point and see if it will got better.

 

[Mastrociambella]

That's not totally good news...seeing the best part of it it's at least better than s21 ultra (I'm using it right now, and i need an overlay app to ramp up brightness without getting blind)

 

[ignaciobarrena]

I upgraded from iPhone 12 to an Iphone 13 Pro. Didn't have any issues with the 12 but I'm feeling some kind of eye-strain with the 13 Pro.

Will give a few days and also let's see if notebookcheck uploads their review...

 

[TDDM]

Good question! I think the confusion here is different metrics.

The video you quoted was measuring "Flicker Index" (or Pulsation Coefficient), which is a different metrics from Modulation (Mod %) / Flicker percentage, which IEEE 1789 was using along with frequency to determine risk level, just as you mentioned. They were not using "Flicker Index". Below are the definition taken from http://www.bio-licht.org/02_resources/info_ieee_2015_standards-1789.pdf:
View attachment 1848445


Picture below is result from a meter that measures not only flicker index but also Mod %. Quick translation for you:

Frequency: 480.19 Hz
Modulation: 97.6 %
Percent Flicker: 95.29%
Flicker Index: 0.306 (Somewhat in line with the Russian folks' video, you see)
Risk alert: High Risk

What's worse is that OP mentioned this kind of high Mod % is detected at all brightness level, which as I mentioned earlier is probably a drawback of LTPO display technology. And to also cut cost on the lower end iPhone 13/mini model, Apple implemented the same PWM policy (480Hz, High Mod % at all brightness) on the entire line (even though in theory iPhone 13/mini could use the same as iPhone 12 Pro)


View attachment 1848442

Thanks for posting this, although it’s disappointing to hear.

 

[1369281]

After reading all of this, it really sounds like Apple engineers have no f-cking clue what they are doing when it comes to this topic. The alternative is that they know exactly what they are doing. Both horrible scenarios for consumers.

Thank you to @changguangyu and @naituil9 for showing what is really going on.

 

[trali]

The video you quoted was measuring "Flicker Index" (or Pulsation Coefficient)

Indeed, the device from video (Radex Lupin) measures Pulsation Coefficient, but it is another name for Mod%, not flicker index.

Quick translation for you:

Frequency: 480.19 Hz
Modulation: 97.6 %
Percent Flicker: 95.29%

Mod% and Percent Flicker are the same thing, but you have provided different values in your translation. Why?

 

[now i see it]

They are very aware of the health implications PWM has on some people.
Or to put it in their jargon, “ We are deeply aware of the detrimental effects screen PWM has on a small number of users.”

 

[trali]

It would be great to know what device has been used to get these measurements.

 

[siksik6]

Returning my iPhone 13 Pro. Really disappointed with Apple this hasn't been addressed yet.

Have never had a problem with Pixel devices, so Google will get my money this year instead. I refuse to use a two year old phone, full stop.

 

[Defying]

I have post concussion syndrome and am light sensitive so I’m forced to use lowest brightness on my phones. Got my 13 Pro Friday and I think I’ll have to return it. Was excited about 120Hz but the PWM backlight feels so weird. My 12 mini seemed to be okay but something about the 13 Pro makes me feel not too great after using it for some time.

Thing is, I checked both of my phones with their slow motion 240FPS cameras and my 12 mini flickers violently at the lowest brightness. Seen here:

Shouldn’t this be causing me issues too? Why does the 13 Pro that flickers faster seem to cause me to feel so much worse? I have a limited understanding of PWM flicker but I thought lower = worse. This is the 13 Pro:

Can anyone help me understand why the 13 Pro feels worse than my 12 mini?

 

[TroyBoy30]

Looks fine to me

 

[naituil9]

Indeed, the device from video (Radex Lupin) measures Pulsation Coefficient, but it is another name for Mod%, not flicker index.




Mod% and Percent Flicker are the same thing, but you have provided different values in your translation. Why?

You can see the device model name right in the picture: OHSP-350BF.
The very right picture should correspond to the "Flicker" mode used in measuring iPhone 13 Pro. (with RiskTip turned on)

Apologies if I did not translate accurately. These definition can be all over the place and I am no expert in this field. The bottom line I'd say is the Mod % metrics (max-min)/(max+min) is close to 100% for iPhone 13 series at all brightness.

I wish PWM is improved over time just as much every one of you do because I really enjoyed the high refresh rate on the iPhone 13 Pro I just got

Spectrometer blue light irradiance and Flicker tester

www.hopoocolor.com

 

[now i see it]

Everyone’s nervous system reacts to flickering light differently. There isn’t a linear correlation between PWM frequency and the effect it will have on someone.
The first iPhone X was a headache throbbing disaster for some people but it didn’t bother others. Same will hold true for the 13. Most will be fine with it while others will experience varying degrees of bad

 

[Wise_rice]

ipad pro 2020 12.9 = 58,820hz
ipad pro 2021 12.9 miniled = 19,190hz
macbook pro 16inch 2019 = 131,700hz


well.. 480hz and 240hz.. isnt that horrible



source:

2021 Apple 12.9-inch M1 iPad Pro with mini LED display shows poor display characteristics including reduced PWM and response times

We tested the PWM and display response times in our 2021 12.9-inch iPad Pro with M1 and found that there are some downsides to Apple's transition to mini LED tech this year. The 2021 12.9-inch iPad Pro not only shows lower PWM compared to the 2020 model but also has noticeably higher response...

www.notebookcheck.net

Apple MacBook Pro 16 2019 Laptop Review: A convincing Core i9-9880H and Radeon Pro 5500M powered multimedia laptop

Notebookcheck.com reviews the flagship model of the MacBook Pro 16, Apple's latest multimedia laptop. The machine comes with an AMD Radeon Pro 5500M GPU and an Intel Core i9-9880H CPU, along with 16 GB of DDR4-2666 RAM and a 1 TB SSD. Read on to find out why have awarded the MacBook Pro 16 top...

www.notebookcheck.net

Hey, in English you use a comma to help visualize 1000 values in math. It is different from the European way of writing where a comma is used to indicate decimal places.
So, the ipad Pro 2020 flickers 120 times faster than iphone 13 pro. A Percentage as high as 50000 is totally imperceivable by the human eye, it blends in together. I only worry about frequencies less than, say 1000.
And also the iPad only uses PWM at low brightness settings. Above a certain percentage it uses DC dimming. You can read about it in the Notebookcheck reviews of those devices.

iPhone 13 pro = 480 hz
ipad pro 2020 12.9 = 58820 hz


What many people here need to understand:
Flicker only matters in low brightness environments. If you have a bright room, your eyes iris will be small, letting in less light. PWM does not bother you at all, during that time.
It gets dangerous during the night, when there is low ambient light and your iris opens up to let more light in. Having a bright pulsating phone screen close to your eyes will affect you if you are sensitive.

Good news is, that the 13 pro will look less blurry while scrolling. That alone will help many people, because the eye perceives a sharper image and has to do less "processing", which can cause migraine for me, personally.

 

[trali]

Indeed, the device from video (Radex Lupin) measures Pulsation Coefficient, but it is another name for Mod%, not flicker index.

I was wrong, Pulsation Coefficient and Mod% are different things.

The bottom line I'd say is the Mod % metrics (max-min)/(max+min) is close to 100% for iPhone 13 series at all brightness.

But I still don’t agree with this

Here is my post in the main thread, let’s continue discussion there:

Eye-strain while using iPhone X and up

I’ll try to put it simple, I promise:) 1. Flickering light could be bad for your eyes and/or brain. Every individual reacts to flicker differently. 2. After certain frequency you can’t see flicker because it’s too fast. But up to the frequencies of 300 Hz (times per second) your brain will...

forums.macrumors.com

I uploaded an image of iPhone screen oscillations, max and min illuminance are 78 and 29 lx, therefore 100*(78-29)/(78+29)=46%.

 

[miniyou64]

Chang is a frequent flier for PWM related posts. Happens every year. Any sensitivity to the “issue” is a severe minority, hence why you never see it become mainstream. He’s a troll and never posts scientific evidence related to the topic.

You can clearly see that his join date was in 2017, when Apple switched to OLED. It’s a troll account, nothing more.

Oh look an Apple engineer. How much is paying to keep Macrumors from reporting on this issue that really affects people?

 

[miniyou64]

We need to start a social media blitz. Need to organize some social accounts and start getting some coordinated traction on this issue.