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by baybal2 1966 days ago
Tame your expectations.

I'm pretty sure Apple's gaslighting field has yet not found a way to bend laws of physics.

Everybody wants a sleek, everyday wearable device, without usability corner cases, but such are physically impossible to make.

Portability, visibility, usability. Choose one.

First, power requirements demand either external power, or extreme power austerity cutting into display, and graphics.

Recon Instruments had first really practical battery powered HUD goggles, and they barely lasted more than an hour in real life use.

The lowest possible power at which you can provide just any much rich graphics is 250mw — the lowest end of most energy efficient SoCs. Possibly, Apple can bruteforce it with 5nm custom ASICs, but not by much, 100mw at max possible with CMOS cells.

Even if you have a magic chip with hypothetical 0 Watt power usage, you will not improve the situation by much as your display will still eat at least 1W, or usually up to 2.5-4W if you use any waveguides.

Daylight visibility is essentially impossible without displays outputting at least 100000+ nits. There are no tricks around that, that's just physics.

There are very few technologies on the horizon which are physically capable of achieving anything better.

Monolithic devices are one, and only ones which can offer sub 1W power use at any much good visual quality.

But, they are very expensive to make. All existing makers are manufacturing on lab scales only. Getting manufacturing out of the lab, and into fabs is impossible without the process technology, getting out of the lab too. And this shortens the list of credible contenders to just 1 company in the world, and guess, it's nor Apple.

Third, even if you agree to a wired up design, where do you get 16k video from? Have you ever seen how thick DP 2.0 cables are?

How do you get latency down?

How do you make even simplest AR interactions not require the wearer to also wear a Quad SLI videogaming PC?

How do you transport 40 gigabits per second of video without having the I/O PHY eat more than the system itself? Only optics can do it under 1W.

Apple can surely put its silicon to good use here, but even a purpose made ASIC video system will be on the edge. It will limit them to the most basic graphics, and pretty much hardcoded, and handcoded use cases to extract maximum power efficiency, and workaround hardware limitations.

It will be a basic HUD, maybe with some GFX, and good video playback options. Essentially an Apple Watch, except you wear it on the head.

I bet they will intentionally limit its functionality to not to let users see performance limitations, and corner cases too often.

2 comments

I agree that the 8k displays sound ambitious but they may have some tricks up their sleeves if they are doing foveated rendering using eye tracking. I think they’ll primarily focus on VR but they may do AR via camera pass through. They graphics in VR mode will be much better than what your claiming though, current stand alone headsets like the Quest 2 have good enough graphics to create a sense of immersion where you forget that what you’re interacting with isn’t actually there. That’s more than enough for virtual meetings and office spaces. If they can nail the facial animations by tracking eye and mouth movement so that non verbal communication crosses the gap they’ll have a winner. The current offerings for meeting and social apps in VR are almost there so Apple has a good shot at pushing it over the line.
I get that it is believe it when you see it, but 16K over USB-C is supposed to happen.