Question, what is the criteria for deciding this to be the case? Could you not just move your face closer to the virtual screen to see finer details?
> "Could you not just move your face closer to the virtual screen to see finer details?"
Sure, but then you have the problem of, say, using an IMAX screen as your computer monitor. The level of head motion required to consume screen content (i.e., a ton of large head movements) would make the device very uncomfortable quite quickly.
The Vision Pro has about ~35ppd and generally people seems to think it hits the bar for monitor replacement. Meta Quest 3 has ~25ppd and generally people seem to think it does not. The Steam Frame is specs-wise much closer to Quest 3 than Vision Pro.
There are some software things you can do to increase legibility of details like text, but ultimately you do need physical pixels.
Apple's "retina" HiDPI monitors typically have PPD well beyond 35 at ordinary viewing distances, even a 1080p 24 inch monitor on your desk can exceed this.
For me personally, 35ppd feels about the minimum I would accept for emulating a monitor for text work in a VR headset, but it's still not good enough for me to even begin thinking about using it to replace any of my monitors.
I agree with you - I would personally consider 35ppd to be the floor for usability for this purpose. It's good in a pinch (need a nice workstation setup in a hotel room?) but I would not currently consider any extant hardware as full-time replacements for a good monitor.
I'm 53 and the Quest 3 is perfectly good as a monitor replacement.
No one who has bought almost any MacBook in the last 10 years or so has had PPD this low either.
One can get by with almost anything in a pinch, it doesn't mean its desirable.
Pixel density != PPD either, although increasing it can certainly help PPD. Lower density desktop displays routinely have higher PPD than most VR headsets - viewing distance matters!
(pixel alignment via lots of rectangular things - windows, buttons; text rendering w/ that in mind; "pixel perfect" historical design philosophy)
The VR PPD is in arbitrary orientations which will lead to more aliasing. MacOS kinda killed their low-dpi experience via bad aliasing as they moved to the hi-dpi regime. Now we have svg-like rendering instead of screen-pixel-aligned baked rasterized UIs.
I've tried that combination in an earlier iteration of Lenovo's smart glasses, and it technically works. But the experience you get is not fun or productive. If you need to do it (say to work on confidential documents in public) you can do it, but it's not something you'd do in a normal setup
This is the main reason many VR games don't let you just walk around and opt for teleportation-based movement systems - your avatar moving while your body doesn't can be quite physically uncomfortable.
There are ways of minimizing this - for example some VR games give you "tunnel vision" by blacking out peripheral vision while the movement is happening. But overall there's a lot of ergo considerations here and no perfect solution. The equivalent for a virtual desktop might be to limit the size of the window while the user is zooming/panning.
https://phrogz.net/tmp/ScreenDensityCalculator.html#find:dis...