I want to leave some of my personal experience. Before I know any screen knowledge, my first tablet is the iPad air 1st generation. I can use it to read pdfs for several hours without any discomfort to my eyes. Later, after the iPad pro 2020 came out, I bought an 11-inch one. I don't know why. I read the pdf on the 11-inch iPad pro 2020. After ten minutes, I felt very uncomfortable for my eyes. I put the pdf on my MacBook pro. I obviously feel more comfortable with my eyes on the screen, I don't understand why, I started searching for related user feedback and screen knowledge, and found the difference between OLED and LED, but I checked, iPad pro is also the screen of LED, I am very confused. Later, I discovered the dimming method, and when I saw this website, I immediately understood the root cause of everything. I ordered iPad air 4, and I can read the pdf for several hours. PWM really has a great impact on my eyes.

[My eyesight is very good, the physical examination is 1.5 1.5, which is the bottom line of the eye chart, the above is for reference

PLEASE, NOTEBOOKCHECK. GET YOUR PWM DATA CORRECT.
I can't believe you guys keep making false PWM measurements FOR YEARS.
That waveform is 100% DC. By no means is that a PWM waveform. Don't just copy what's on the oscilloscope.

The Pro 11 uses PWM at 1316 Hz, but the 12.9 uses 58820 Hz? How can that be right? I think a cell phone camera can detect PWM at 1316 Hz.

@notebookcheck
Please check your own PWM screenshot. It says "1.316 Hz". What does that mean? It means " One point three". That is not 1.3 MHz but instead 1.3 kHz. I suppose since you guys are German, you confused the English dot with the German Komma. Please check your other reviews that have insanely high PWM as well. They all suffer from this problem.

Great Review . thank you for sharing . I'm a professional artist and I've been drawing digitally since 2018 . i do this on a XP-Pen Artist 22E Pro 22" screen drawing tablet right now. I am searching for a 2nd device so i can sketch on the couch, or take it with me. So far, with all the plus and cons, the Ipad Pro are really (my) best choice.

I was able to spend a few hours with the 12.9 2020 Pro and maybe it's using PWM, maybe it's not, but it didn't seem to bother my eyes.

FWIW, I couldn't use an Apple Watch 3 for more a than a minute or so without eye strain, but I'm fine with the Apple Watch 5. The newer iPhone's with OLED's cause instant pain, but the 11 vanilla does not.

It'll be interesting to see what these guys find for the big iPad in terms of flicker frequency.

hotter, smaller battery, and pwm. in exchange of a camera no one asked for

what an upgrade

At which level of brightness there is no flickering ? (Pmw )

>The rigidity of the tablet is okay
Okay? I literally saw a guy rip it apart with his bare hands, it's most certainly not okay. 5.9mm is pointlessly thin, 2mm thicker and 200g more could make it far sturdier and with a larger battery, likely better thermals too though I don't know if Apple's tablets still need that.

"this is what an update should look like"

??
I think you guys hit the new low.
wha't's so special about this generation's update?
2020 is basically the same 2018 ipad pro in disguise.  the only substantial upgrade is AR camera which is not yet utilized by mass.

Quote from: asgarder on April 15, 2020, 00:31:33
To add to that, I'm not even sure that we actually are looking at PWM, the scope trace next to the frequency measurement just displays a noisy signal.
If anyone from notebookcheck actually reads through these comments, it would be great to get a video of the PWM in action like they did for the recent Macbook Air 2020 review, because there, what they call PWM isn't actual pulse width modulation, it's just a boost circuit with no output capacitor which oscillates slightly between the charge and discharge phase of its cycle, so the output wave will oscillate between say 10 and 12 volts, with the very telling exponential rising and falling edges.
This is completely different from PWM that oscillates at a low frequency between say 12 and 0 volts.

You sound a LOT more knowledgeable about this than I know I am, so thanks!!

I know the review of a Sony TV states there IS flicker, but it's not PWM. Said TV does NOT bother me. Maybe this might be similar to what you're trying to explain?

Anyway, I appreciate your comment and hopefully we will see some BIG buttons for FORUM @ the tops of these web pages as well as some moderation from the testers here @ NC.

Worst case scenario, I'd have to try both sizes out, return both, and wait... :p

Quote from: Redaktion on April 12, 2020, 23:22:58

...yada...yada...AWESOME iPad review.

Help us Redaktion, you're one of many new hopes‽‽‽

To add to that, I'm not even sure that we actually are looking at PWM, the scope trace next to the frequency measurement just displays a noisy signal.
If anyone from notebookcheck actually reads through these comments, it would be great to get a video of the PWM in action like they did for the recent Macbook Air 2020 review, because there, what they call PWM isn't actual pulse width modulation, it's just a boost circuit with no output capacitor which oscillates slightly between the charge and discharge phase of its cycle, so the output wave will oscillate between say 10 and 12 volts, with the very telling exponential rising and falling edges.
This is completely different from PWM that oscillates at a low frequency between say 12 and 0 volts.

Quote from: asgarder on April 14, 2020, 03:29:58

Quote from: jodiuh on April 14, 2020, 02:39:20

Quote from: henry james on April 13, 2020, 03:28:06
seriously.. for a content-consumption device, reading, watching movies, casual email etc.. how can they have gone back to using PWM in this generation?

I'm blown away about this. We've had Asus, BenQ, and Dell monitors advertising flicker free for years. Not only will we be viewing this a LOT, but it's quite pricey in the higher storage tiers with LTE.

I'm holding out hope for the 12.9", but maybe this'll work to our advantage if that's got PWM flickering as well. I'd be waiting for the falls rumored mini LED and hopefully we'll get an A14X as well. My only concern's that mini LED uses dimming zones AFAIK and that might mean PWM.

Are you out of your mind, the PWM frequency is 1.3MHz, that's 1.3 million times per second, it's a higher frequency than AM radio. I'll give you all my possessions if you can actually see something blinking at 1.3MHz

It could be 1300 and I still wouldn't go near it. I'm not God. I don't know what my eyes can actually perceive and translate into an adverse affect to eye heath. Some of us still use incandescents for this same reason! :D

I know of no other place to determine PWM as well as here. So that's why I'm posting and hoping word gets out more and more about the problems this tech can cause.

I'd rather have a flicker free 12.9" A12Z powered iPad Pro with NO PWM than a hypothetical...

14" A14X powered iPad Pro using pulse width modulated backlighting for the Micro LED with proper dimming zones that supports both HDR10 and Dolby Vision.

It could have the same camera module from the upcoming 12 Pro, 8 GB of RAM, 2 USB-C's, a headphone jack, water resistance, and come with a free Lifeproof case. It still wouldn't matter.

It's that important. Flicker free is that important. My eyes are that important.

Are you out of your mind, the PWM frequency is 1.3MHz, that's 1.3 million times per second, it's a higher frequency than AM radio. I'll give you all my possessions if you can actually see something blinking at 1.3MHz
[/quote]

this has been rehashed a million times across the web... it's not that you can SEE the flickering (no one can), it's that it produces an effect of eyestrain over the longer term. people feel this (including myself); it made me choose the iPhone 11 over the 11 Pro simply because i hated the PWM on the Pro.

in 2020, no devices should be doing this shady cheap dimming crap at the expense of users' eyesight, health and comfort. i'd take reduced battery life any day for clean clear light.

Quote from: jodiuh on April 14, 2020, 02:39:20

Quote from: henry james on April 13, 2020, 03:28:06
seriously.. for a content-consumption device, reading, watching movies, casual email etc.. how can they have gone back to using PWM in this generation?

I'm blown away about this. We've had Asus, BenQ, and Dell monitors advertising flicker free for years. Not only will we be viewing this a LOT, but it's quite pricey in the higher storage tiers with LTE.

I'm holding out hope for the 12.9", but maybe this'll work to our advantage if that's got PWM flickering as well. I'd be waiting for the falls rumored mini LED and hopefully we'll get an A14X as well. My only concern's that mini LED uses dimming zones AFAIK and that might mean PWM.

Are you out of your mind, the PWM frequency is 1.3MHz, that's 1.3 million times per second, it's a higher frequency than AM radio. I'll give you all my possessions if you can actually see something blinking at 1.3MHz