I feel eyestrain on PWM displays, so I am looking for a smartphone with DC dimming. Any with /e/ OS official support?
I know Sony Zenfone 8 supports DC dimming and I tested it, but it has too small display for me.
That’s going to be a tough option to find. DC dimming requires a DC-DC converter and PWM dimming requires only a few lines of code. Just about all makers use PWM to reduce production cost and circuit board footprint.
DC dimming is superior in every respect so I would expect if a maker provides it there would be no option for PWM eliminating any need for special software support. But I don’t know since I’ve not run into any issue with PWM dimming myself and have not looked into it.
As a workaround, you may also consider a phone with a high PWM rate (e.g. more than 900 Hz or even 2000 Hz), as described here: Best phones for PWM/Flicker sensitive people | Android Central
EDIT/Correction: The article even mentions that several of these phones offer the possibility to enable DC dimming (or something close to it).
Even if a phone with a high PWM rate works for you, the problem is obviously to find one that is also supported by /e/OS. This seems to be the case for the Motorola Edge 40 Pro.
Furthermore, the Android Central article gives a first overview which vendors may be a good choice for you and check their models in the list of supported devices. You can then take a look at reviews like the ones on NotebookCheck.net where the PWM rate is tested.
One example is the OnePlus Nord N10, which does not use an OLED panel with PWM, but an LCD panel (see its NotebookCheck.net review), or the Nothing CMF Phone 1, which has a higher (secondary) rate of 960 Hz (see its NotebookCheck.net review).
If you have found a good device, you may then use your favourite search engine to further see what experience PWM sensitive people have made with it.
Still, the Android Central article states that
People who are sensitive to display flicker aren’t all sensitive to the same problems, so what works for one person may not work for another.
There is at least hope that more vendors will choose displays with higher PWM rate in the future (see e.g. this rumour about the Google Pixel 10).
2 Likes
LCD panels are not as bright as OLED and can suffer more easily from readability in high ambient light. Also the brightness depends on the backlight which may use either PWM or DC dimming. I don’t know on that particular OnePlus phone, but you’d have to check.
In any case I think a higher PWM frequency is going to be your best solution. I mean you might be able to find a new(ish) model phone with DC dimming but probably not one that is also /e/os compatible. The Motorola Edge 40 Pro sounds like a winner.
1 Like
According to the Android Central article, the Edge 40 Pro even seems to support DC dimming (the NotebookCheck.net review is a bit vague in this regard IMHO).
They can do DC dimming at higher brightness using a small inexpensive voltage regulator since there’s not a lot of voltage difference between the battery and what they’re feeding the screen. At lower screen brightness they can’t use that method due to heat production and inefficiency so they have to switch to PWM. Ideally you would use DC-DC conversion through the whole range. It’s highly efficient and generates little heat, but there’s the right way and the cheap way.
1 Like
I remember that when the Fairphone 5 was launched with Fairphone OS (by now, Fairphone calls it “Android OS”), it did come with DC dimming, but I cannot say if that is present in the Fairphone 5 on /e/OS as well. Maybe a Fairphone 5 user can check this on her/his device.
4 Likes
Thanks for great answers.
Motorola looks promising, thank you. Mentioned NotebookCheck review says that
We noticed screen flickering at very low screen brightness, but you can activate a “Flicker Prevention” mode in the display settings, which adapts the flickering to the refresh rate and thus makes it inconspicuous.
Well, it depends if /e/ OS supports this Flicker prevention mode.
I think Nothing Phone 3a could be also fine, according to this PWM test video:
The Nothing Phone 3a makes substantial improvements in display comfort when compared to the Nothing Phone 2a. Nothing Phone 3a has significantly lower modulation rates and offers no dithering. Both phones use DC dimming above 50% brightness and switch to 2160Hz PWM dimming below 50% brightness.
But in the NotebookCheck review is it said
The display backlight flickers at 90 Hz (worst case, e.g., utilizing PWM) . The frequency of 90 Hz is very low, so the flickering may cause eyestrain and headaches after extended use.
NotebookCheck seems to be quite critical about the flicker. Anyway, we don’t have /e/ OS for Nothing 3a. Do you think it would come?
/e/OS is (usually) based on LineageOS. Unfortunately, LineageOS currently only supports the Nothing Phone 1 and no newer model, so I think that an /e/OS release is unlikely.
On the other hand, the CMF Phone 1 is not supported by LineageOS and still an official Murena device. Maybe /e/OS v 3.0 will support the Nothing 3a?
One advantage is the official support of /e/OS on the Fairphone 5, so @jirkamat may order it directly from Fairphone or Murena with /e/OS preinstalled. If the DC dimming does not work as intended, he may send it back. (This is obviously only an option if the Fairphone 5 meets @jirkamat’s requirements; moreover, you may use the forum search to check whether any bugs are present in /e/OS for the FP5 that you would consider a showstopper. I remember that there has been a problem with the 90 Hz refresh rate and that you should set it to 60 Hz instead.)