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Haven't phones, watches and tablets been using low refresh rates to enable battery improvements for a while?

The Apple Watch Series 5 (2019) has a refresh rate down to 1Hz.

M4 iPad Pro lacks always-on display despite OLED panel with variable refresh rate (2024):

https://9to5mac.com/2024/05/09/m4-ipad-pro-always-on-display...

Dell needs to sell these XPS. The AI button doesn't do the trick, so battery life may do it.
Yes but I’m unaware of larger ones.
iPad Pro only goes down to 10 FPS. This may be the display of the upcoming MacBook Pro.
OLED iPad dont have always on because of burn-in. Considering people certainly use it as photo frame, notification and time daahboars, kitchen recipe book, etc.

Less of a problem for iphones that unlikely to stay for a week in the same place plugged in and unused.

I don't think many people are spending $1k on an iPad Pro, the only iPad with OLED, to use as a picture frame.
Phones and watches do that with LTPO OLED which I don't believe exists at higher screen sizes although I'm not sure why. This is supposed to be special because it isn't OLED so should be able to get brighter and not have to worry about burn in.
Panel Self Refresh should largely just work, and I believe has been on laptops for a long long time. Here's Intel demo'ing it in 2011. https://www.theregister.com/2011/09/14/intel_demos_panel_sel...

I'm not sure that there's really anything new here? 1Hz might be lower. Adoption might be not that good. But this might just be iteration on something that many folks have just not really taken good advantage of till now. There's perhaps signficiant display tech advancements to get the Hz low, without having significant G-Sync style screen-buffers to support it.

One factor that might be interesting, I don't know if there's a partial refresh anywhere. Having something moving on the screen but everything else stable would be neat to optimize for. I often have a video going in part of a screen. But that doesn't mean the whole screen needs to redraw.

I’m not an expert here, but …

CRTs needed to be refreshed to keep the phosphors glowing. But all screens are now digital: why is there a refresh rate at all?

Can’t we memory-map the actual hardware bits behind each pixel and just draw directly (using PCIe or whatever)?

>M4 iPad Pro lacks always-on display despite OLED panel with variable refresh rate (2024):

Brightness, Uniformity, Colour Accuracy etc. It is hard as we take more and more features for granted. There is also cost issues, which is why you only see them in smaller screens.

What LG is pitching here is basically bringing that 1Hz floor capability to large laptop panels
this is just regurgitating the manufacturer's claim. I believe it when I see it. Most of display energy use is to turn on the OLED/backlight. They're claiming, because our display flickers less, it's 48% more efficient now.
> LG’s press release leaves several questions unanswered, including the source of the “Oxide” name...

> Source: https://www.pcworld.com/article/3096432 [2026-03-23]

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> HKC has announced a new laptop display panel that supports adaptive refresh across a 1 to 60Hz range, including a 1Hz mode for static content. HKC says the panel uses an Oxide (metal-oxide TFT) backplane and its low leakage characteristics to keep the image stable even at 1Hz.

> Source: https://videocardz.com/newz/hkc-reveals-1hz-to-60hz-adaptive... [2025-12-29]

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> History is always changing behind us, and the past changes a little every time we retell it. ~ Hilary Mantel

As soon as I saw this announced, I wondered if this is why we haven’t seen OLED MacBook Pro yet.

Apple already uses similar tech on the phones and watches.

So if a pixel is not refreshed, it doesn't use any power?
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I once had an external monitor with a maximum refresh rate of 30 Hz, and mouse movements were noticeably sluggish. It was part of a multi-monitor setup, so it was very obvious as I moved the mouse between monitors.

I'm not sure if this LG display will have the same issue, but I won't be an early adopter.

Apple introduced variable refresh rate back in 2015. That’s over a decade ago, I’m sure there’s some new tech involved here, but quite the omission.
Apple might have convinced some gullible customers that this was something new.

But to the rest of the world variable refresh rate existed for years by then. As is with most Apple "inventions".

In this case the patent goes back to 1982: https://patents.google.com/patent/US4511892A/en

And this tech has been available in consumer hardware since... ? Take a guess.
Sorry, might be obvious to some, but is that rate applied to the whole screen or can certain parts be limited to 1Hz whilst others are at a higher rate?

The ability to vary it seems like it would be valuable as there are significant portions of a screen that remain fairly static for longer periods but equally there are sections that would need to change more often and would thus mess with the ability to stick to a low rate if it's a whole screen all-or-nothing scenario.

Today it's mostly "all-or-nothing" at the panel level, but under the hood there's already a lot of cleverness trying to approximate the behavior you're describing
> That will help save enormous amounts of power: up to 48 percent on a single charge,

Why does refresh rate have such a large impact on power consumption? I understand that the control electronics are 60x more active at 60 Hz than 1 Hz, but shouldn't the light emission itself be the dominant source of power consumption by far?

I think the idea is that in an always-on display mode, most of the screen is black and the rest is dim, so circuitry power budget becomes a much larger fraction of overhead.
I used to be a display architect about 15 years back (for Qualcomm mirasol, et al), so my knowledge of the specifics / numbers is outdated. Sharing what I know.

High pixel density displays have disproportionately higher display refresh power (not just proportional to the total number of pixels as the column lines capacitances need to be driven again for writing each row of pixels). This was an important concern as high pixel densities were coming along.

Display needs fast refreshing not just because pixel would lose charge, but because the a refresh can be visible or result in flicker. Some pixels tech require flipping polarity on each refresh but the curves are not exactly symmetric between polarities, and further, this can vary across the panel. A fast enough refresh hides the mismatch.

It doesn't. They take extreme use cases such as watching video until the battery depletes at maximum brightness where 90% of power consumption is the display. But in realistic use cases the fraction of power draw consumed by the display is much smaller when the CPU is actually doing things.
Your GPU rendering 1 frame vs your GPU rendering 60 frames.
Really disappointing to only learn this after a decade, but on Linux changing from 60hz to 40hz decreased my power draw by 40% in the last hour since reading this comment.
Anyone who has accidentally snapped the controller off a working LCD can tell you that the pixel capacitance keeps the colours approximately correct for about 10 seconds before it all becomes a murky shadowy mess...

So it makes sense you could cut the refresh time down to a second to save power...

Although one wonders if it's worth it when the backlight uses far more power than the control electronics...

Perhaps it can do 50Hz, which may be beneficial for emulating PAL systems.
Today I learned, laptop comes with backlit vs edgelit panel. And, they have different energy consumption.

There are also mini LED laptop for creative work. Few more things to check before buying new laptop.

The real unanswered question is how much of this is the panel itself and how much is baked into Windows.

Saving battery is nice, but I'm not leaving Linux for that misery any time soon

Make a new phone with this please.
Tried to open this page on my mobile, good grief the changing advert spam overload kills the reading experience.
What's the chance this will even work on Linux with GNOME?
> A 1Hz panel is almost, but not quite, on the level of an e-ink panel, which isn’t the prettiest to look at.

level of what? Power consumption? dude e-ink takes 0 power between refreshs.

And e-ink is pretty?

Horrid website: forced cookies, invisible adverts (Mamma Mia, anyone?), and that thing where it’s a page of garbage links when you go back. I will never click a PC World URL again.
Still waiting on e-ink laptops. This just seems like a no-brainer.
Sure dropping toward 1Hz could be huge. But the moment you scroll, watch video, or even have subtle UI animations, you're back in higher refresh territory
I'm guessing that for this to work you need to be able to selectively refresh parts of the screen at different rates? a 1Hz refresh rate would be rubbish just to follow the mouse cursor, so at least that part of the screen needs to refresh faster. However, it does make sense for the parts of the screen that are mostly static. Looking at my screen as I type this, the only part that needs a high-refresh rate is the text-box where I'm typing (I can type several keys per second so I wouldn't want a refresh rate of 1 Hz). However, the rest of the screen is not changing at all so a slow refresh is perfectly fine.
Modern software regularly takes like 1 second to load anyways. 200ms is the minimum human reaction time, so adding 100ms would only add like 50% to the REPL user interaction. Something like 10Hz might be quite usable while minimally contributing to lag.

The idea of having a 60Hz screen is nice, but in practice it turns out that display refresh rate is not the bottleneck for most software.