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LG's new 1Hz display is the secret behind a new laptop's battery life

pcworld.com

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Re: LG's new 1Hz display is the secret behind a new laptop's battery life

#161

Post by alok-g »

saltcured wrote: post #159
alok-g wrote: post #150

Earlier quoted context omitted.

Being a key technology architect for it (not the core inventor), I know all about it, and then some more! I cannot however talk publicly about it. :-( It has been a disappointment for me as well. I had worked on it for nearly eight years. The idea was so interesting--using thin-film interference for creating images is akin to shaping Newton's rings into arbitrary images, something which even Newton would not have ima…

My fantasy display would be some kind of reflective-mode display that can passively show static images like e-ink, have partial updates like MIP LCD in wearables, response times like modern LCD and AMOLED, and "super-real" contrast/gain. I.e. actually do wavelength conversion to not just reflect a narrow-pass filtered version of the ambient light, but convert that broad spectrum energy into the desired visuals, so it…

>> My fantasy display would be some kind of reflective-mode display that can passively show static images like e-ink, have partial updates like MIP LCD in wearables, response times like modern LCD and AMOLED, and "super-real" contrast/gain.

What about cost? :-) It is an important factor too outside of the fantasy world and can kill new display technologies. The latter often suffer from yield issues (dead pixels, etc.) during early phases of R&D which can make initial costs be still higher as compared to already matured technologies.

>> I.e. actually do wavelength conversion to not just reflect a narrow-pass filtered version of the ambient light, but convert that broad spectrum energy into the desired visuals

Reflecting filtered version of the ambient light, if done efficiently, brings the display to as bright as other natural/common objects around. So it should be good enough for most purposes, even in a somewhat darker ambient with eyes adjusted.

It would not however be attention-grabbing by being brighter than those surrounding objects. So many users, often used to seeing brighter emissive displays, still do not pick those as a preference.

>> I can only imagine this being either:

>> ...

Another way to make it look brighter is to reflect more light towards the users/eyes while capturing it from broader directions. This would compromise on viewing angle (unless more fantasy tech is brought in), but I think this in itself take the display to wow levels.

Re: LG's new 1Hz display is the secret behind a new laptop's battery life

#162

Post by moffkalast »

pier25 wrote: post #143
bracketfocus wrote: post #28

Earlier quoted context omitted.

From what I understand, the laptop will reduce the refresh rate (of the entire display) to as low as 1Hz if what is being displayed effectively “allows” it. For example: - reading an article with intermittent scrolling - typing with periodic breaks

Who “decides” the frame rate? Does the gpu keep sending data and the monitor checks to determine when pixels change?

Probably the display board, anything else would be subject to OS and GPU driver support and it would never work anywhere.

Re: LG's new 1Hz display is the secret behind a new laptop's battery life

#163

Post by veqq »

qnleigh wrote: post #32

> 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?

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.

Re: LG's new 1Hz display is the secret behind a new laptop's battery life

#164

Post by iAMkenough »

mnw21cam wrote: post #115
dlcarrier wrote: post #38

Earlier quoted context omitted.

It's for OLED screens, so there's no backlight, but also no persistence.

It's an LCD display.

Are you sure? Article says:

> A 1Hz panel is almost, but not quite, on the level of an e-ink panel, which isn’t the prettiest to look at. LG’s panel also uses LED technology, the mainstream panel technology that’s being overtaken at the high end by OLED panels with essentially perfect contrast.

Re: LG's new 1Hz display is the secret behind a new laptop's battery life

#165

Post by glitchcrab »

k4rli wrote: post #103
hedora wrote: post #53

Earlier quoted context omitted.

What's the real-world battery life though? My mac gets 8 hours real world; 16 in benchmarks; 24 claimed by apple. Assuming the xps has the same size battery, and this really reduces power consumption by 48%, I'd expect 16 hours real world, 32 in benchmarks and 48 in some workload Dell can cherry pick.

Both my last two XPSes have had shit battery life. Maybe 3.5h when new and only 2h after a few months of use. They also experience a lot of thermal throttling (i7 12700h, 9750h) and newer updates have removed the option of undervolting which used to fix that. Positive is that the battery life couldn't possibly get worse with newer ones.

I have a December 2024 XPS 15 and I regularly get 7-8 hours out of a charge whilst doing a mixture of tasks. On Linux too, no less.

Re: LG's new 1Hz display is the secret behind a new laptop's battery life

#166

Post by iAMkenough »

ErneX wrote: post #125
ErneX wrote: post #41

Earlier quoted context omitted.

These are self emissive pixels.

Edit: apparently not? Article says OLED with this tech will come in 2027, seems this panel it’s LCD

Article also says "LG’s panel also uses LED technology"

Re: LG's new 1Hz display is the secret behind a new laptop's battery life

#167

Post by mmooss »

alok-g wrote: post #87
qnleigh wrote: post #32

> 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 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 hi…

> the column lines capacitances need to be driven again for writing each row of pixels

Not my field so please forgive a possibly obvious question: That seems true regardless of the pixel count (?), so for that process why wouldn't power also be proportional to the pixel count?

I notice I'm saying 'pixel count' and you are saying 'pixel density'; does it have something to do with their proximity to each other?

Re: LG's new 1Hz display is the secret behind a new laptop's battery life

#168

Post by quantumink »

iknowstuff wrote: post #112
quantumink wrote: post #85

Earlier quoted context omitted.

Last I checked: the XPS was one of the few laptop product lines offering native Linux (Ubuntu) as an alternative default configuration option to order It's how I got mine about 6-7 years back anyways, still works great (except the battery) ...never let windows get it's claws into the machine in the first place Edit: to add, I realized over time that having a battery that lasts longer just can't seem to beat my older…

Powerbanks fill that role well. We have USB-C PD now

While I concede that powerbanks may satisfy the proximal problem - literally making charging available on demand... Consider that it does not in any way resolve the distal problem of having a 'portable computing device', which heavily compromises on the 'portable' aspect - by forcing a state of permanent battery anxiety without external life support (i.e. no power source - dead in minutes of intensive work) The powerbank is a fine workaround to be fair, but as I see it: still a workaround at best. The ability to swap a battery without getting into things like soldering - allows for far more flexible functionality and longevity than a powerbank could.

That is without even mentioning the ultimate problem of parts sustainability and longevity. When you can swap individual components as they degrade, it's possible to use the rest of the machine for far longer than a degraded battery or a failing SSD would allow.

Powerbanks simply feel like treating symptoms, instead of rehabilitating the system itself (obviously still use them for phones and such of course)

Re: LG's new 1Hz display is the secret behind a new laptop's battery life

#169

Post by kbolino »

__d wrote: post #90
jauntywundrkind wrote: post #19

Earlier quoted context omitted.

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.…

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)?

I think you're assuming that LCDs all have framebuffers, but this is not the case. A basic/cheap LCD does not store the state of its pixels anywhere. It electrically refreshes them as the signal comes in, much like a CRT. The pixels are blocking light instead of emitting it, but they will still fade out if left unrefreshed for long. So, the simple answer is, you can't get direct access to something when it doesn't even exist in the first place.

Re: LG's new 1Hz display is the secret behind a new laptop's battery life

#170

Post by saltcured »

alok-g wrote: post #161
saltcured wrote: post #159

Earlier quoted context omitted.

My fantasy display would be some kind of reflective-mode display that can passively show static images like e-ink, have partial updates like MIP LCD in wearables, response times like modern LCD and AMOLED, and "super-real" contrast/gain. I.e. actually do wavelength conversion to not just reflect a narrow-pass filtered version of the ambient light, but convert that broad spectrum energy into the desired visuals, so it…

>> My fantasy display would be some kind of reflective-mode display that can passively show static images like e-ink, have partial updates like MIP LCD in wearables, response times like modern LCD and AMOLED, and "super-real" contrast/gain. What about cost? :-) It is an important factor too outside of the fantasy world and can kill new display technologies. The latter often suffer from yield issues (dead pixels, etc.…

Well, the reflectivity of color MIP LCD is not very satisfactory. It is barely adequate, even for people like me who are fans. This is both because of the narrow-band RGB filtering and the inherent losses of the polarization-based switching method. Even the "white" state is discarding most polarizations of the ambient light, and then the darker colors are even blocking that.

My fantasy is having the reflectivity be at least as good as good white paper, and with deep contrast too.

It also needs to be brighter in practice than normal objects because, no matter what, it will have to overcome some glare from whatever protective glass and touch sensing layers there are over the actual display.

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