VR focal distance question...

[Rbass 27]

Need some knowledge on VR and less than perfect vision from the experts. So I wear progressive lens glasses, being near sighted, so I can see distance out of the upper half of the lens and gradually down to close in at the lower part of the lens. I’m wondering what “distance” the VR lenses focus at, being that the actual screens are only a few inches in front of your eyes. Would we need to be able to see clearly at just a few inches, or would our eyes be focused farther out? I’m not very clear on how our vision works with a headset and screens so physically close to our eyes. I don’t know anyone with a VR rig, and I’m trying to figure out if I’ll have a vision issue before getting a rig going, or will maybe need a special lens prescription for VR? As always, any insights are very appreciated.

[HiFlyer 9,343]

3 minutes ago, Rbass said:

Need some knowledge on VR and less than perfect vision from the experts. So I wear progressive lens glasses, being near sighted, so I can see distance out of the upper half of the lens and gradually down to close in at the lower part of the lens. I’m wondering what “distance” the VR lenses focus at, being that the actual screens are only a few inches in front of your eyes. Would we need to be able to see clearly at just a few inches, or would our eyes be focused farther out? I’m not very clear on how our vision works with a headset and screens so physically close to our eyes. I don’t know anyone with a VR rig, and I’m trying to figure out if I’ll have a vision issue before getting a rig going, or will maybe need a special lens prescription for VR? As always, any insights are very appreciated.

If you are nearsighted to the point of needing glasses, you will need to either wear your glasses while using a VR headset, or buy glasses inserts for the headset.

[Pilot53 543]

^^ in VR it behaves exactly as the real world as far as eyesight.  Far away objects look far away to your eyes, and close up objects look close up.

[mickatmian 52]

I use my distance glasses and can see both near and far perfectly in the Rift s.

For information as far as I am aware the rift s is the only headset that accommodates glasses.

Mick

[HiFlyer 9,343]

4 hours ago, mickatmian said:

I use my distance glasses and can see both near and far perfectly in the Rift s.

For information as far as I am aware the rift s is the only headset that accommodates glasses.

Mick

Many headsets accommodate glasses, but in my experience it's much more convenient to purchase prescription inserts for your headset. https://widmovr.com/

 

Edited July 12, 2020 by HiFlyer

[Rbass 27]

8 hours ago, Pilot53 said:

^^ in VR it behaves exactly as the real world as far as eyesight.  Far away objects look far away to your eyes, and close up objects look close up.

I get that, but what I don't understand is the focal length. The physical screens we see are inches away. Do the lenses allow the eye to focus at a different length or just the inches to tbe screens? If so, what would be the focal distance? Because there is basically zero distance to the flat screens, as opposed to real life objects all at different distances,  there has to be some kind of distance the headset focuses our eyes. Im wondering what that"virtual" distance is so I can figure out my glasses situation.  Appreciate the input.

Edited July 12, 2020 by Rbass

[HiFlyer 9,343]

The focal length is long distance. Essentially on Infinity

[Rbass 27]

4 hours ago, mickatmian said:

I use my distance glasses and can see both near and far perfectly in the Rift s.

For information as far as I am aware the rift s is the only headset that accommodates glasses.

Mick

That is good to know, thanks!

[HiFlyer 9,343]

To be more accurate focal length is from 2 m to Infinity

Edited July 12, 2020 by HiFlyer

[Rbass 27]

Good stuff, thanks guys.

 

[mickatmian 52]

21 hours ago, HiFlyer said:

Many headsets accommodate glasses, but in my experience it's much more convenient to purchase prescription inserts for your headset. https://widmovr.com/

Yes of course prescription inserts are obviously the best way to go.

I was merely pointing out that the Rift s accommodates glasses by sliding the front of the headset forward, (is that unique among headsets or are there others) and from my own experience is quite comfortable with glasses, at least for me. I had the original rift not good with glasses, also the HP Reverb for me the reverb was so uncomfortable with or without glasses I sent it back. 

Mick

[HiFlyer 9,343]

7 hours ago, mickatmian said:

(is that unique among headsets or are there others)

Quite a few headsets make accommodations for glasses, though some do that better than others.....

The quest, for instance, actually comes with a custom eyeglass spacer, The Valve Index has an "eye relief knob" that moves the lenses backwards and forwards also to accommodate glasses, etc.

[guit32 7]

It will depend of the headset.

the vive pro and the vive have a short focal distance about 1 0r 1,5 m. I am also nearsight (-2/-1.75) and I don’t need glasses for these 2 headseat  

I have own also a reverb and the focal distance is very long ( infinity) for this headset I bought vrlenses. 

Many headset are like the reverb (the samsung is, the index also). 

 

Edited July 13, 2020 by guit32

[OzWhitey 3,353]

On 7/12/2020 at 8:45 PM, HiFlyer said:

To be more accurate focal length is from 2 m to Infinity

I don't think that's more accurate - according to my limited understanding of optics, that's not what a focal length is.

https://en.wikipedia.org/wiki/Focal_length#:~:text=The%20focal%20length%20of%20an,that%20the%20system%20diverges%20light.

To the OP:

With VR, your eyes are physically about 5cm from the screen. Obviously, none of us would be very good at focusing on that, so the lens system makes the 2D plane of the screen effectively further from the eye than it otherwise would be. This will vary from headset to headset, depending on the optics. 

The question then, is what distance are your eyes trying to focus at with a Rift S? 

This thread - https://www.reddit.com/r/oculus/comments/bjgfp4/focal_distance_rift_s/ - suggests that the older Rift had a focus distance equivalent to 1.5m, but the poster who has myopia (as you do) feels that the Rift S is equivalent to focusing on a real object at 50-60cm from the eyes.

The secondary issue is presbyopia, the age-related lens condition that will affect many simmers in this forum (as the great majority of those over 40-50 years of age have this condition). In short, your ability to focus on near objects (accommodate) deteriorates with time due to alterations in lens compliance. So a younger lens will be able to compensate if the screen image is a bit too close, whereas an older simmer with the same baseline refraction will struggle.

What does this mean? It means that there is a fair chance that you'll be OK if you can focus on an object that is 50cm-ish away, and if not you'll be wearing glasses with the Rift S.

 

 

 

[Rbass 27]

Thanks for the input Oz.

So it seems the answer is going to be finding out what the real focal length is for the headset I choose, then find out what my prescription is for that distance, if any. It also seems that for whatever reason, some of the headset makers do not state that spec, and depending on the hmd may be difficult to find out. The good news is that I only need one lens prescription for VR, and not have to worry about near to far changes in my vision. That would make prescription lens inserts tbe perfect solution, if I can get the info on actual focal length.

Thats for the input guys, very helpful.