Comment by hedora

1 day ago

This is an OLED display, so I don't think the control electronics are actually any less active. (They would be for LCD, which is where most of these low-refresh-rate optimizations make sense.)

The connection between the GPU and the display has been run length encoded (or better) since forever, since that reduces the amount of energy used to send the next frame to the display controller. Maybe by "1Hz" they mean they also only send diffs between frames? That'd be a bigger win than "1Hz" for most use cases.

But, to answer your question, the light emission and computation of the frames (which can be skipped for idle screen regions, regardless of frame rate) should dwarf the transmission cost of sending the frame from the GPU to the panel.

The more I think about this, the less sense it makes. (The next step in my analysis would involve computing the wattage requirements of the CPU, GPU and light emission, then comparing that to the KWh of the laptop battery + advertised battery life.

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hedora

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thelastgallon  1 day ago

Not OLED.

> LG Display is also preparing to begin mass production of a 1Hz OLED panel incorporating the same technology in 2027.

karlgkk  1 day ago

> The more I think about this, the less sense it makes

And yet, it’s the fundamental technology enabling always on phone and smartwatch displays

The intent of this is to reduce the time that the CPU, GPU, and display controller is in an active state (as well as small reductions in power of components in between those stages).

  • DoctorOetker  21 hours ago

    for small screen sizes and low information density displays, like a watch that updates every second this makes a lot of sense

    it would make a lot of sense in situations where the average light generating energy is substantially smaller:

    pretend you are a single pixel on a screen (laptop, TV) which emits photons in a large cone of steradians, of which a viewer's pupil makes up a tiny pencil ray; 99.99% of the light just misses an observer's pupils. in this case this technology seems to offer few benefits, since the energy consumed by the link (generating a clock and transmitting data over wires) is dwarfed by the energy consumed in generating all this light (which mostly misses human eye pupils)!

    Now consider smart glasses / HUD's; the display designer knows the approximate position of the viewer's eyes. The optical train can be designed so that a significantly larger fraction of generated photons arrive on the retina. Indeed XReal or NReal's line of smart glasses consume about 0.5 W! In such a scenario the links energy consumption becomes a sizable proportion of the energy consumption; hence having a low energy state that still presents content but updates less frequently makes sense.

    One would have expected smart glasses to already outcompete smartphones and laptops, just by prolonged battery life, or conversely, splitting the difference in energy saved, one could keep half of the energy saved (doubling battery life) while allocating the other half of the energy for more intensive calculations (GPU, CPU etc.).