VR focal distance question...

[mickatmian 52]

This is from the FAQ on the VR lens lab site.

I use progressive lenses. Which prescription do I submit?
To make the lens, we need your distance prescription. VR headsets focus at distance, so we mainly use the far vision prescription. We’ll calculate the compensation power based on your age for the near distance vision.

Mick

[HiFlyer 9,343]

On 7/14/2020 at 5:21 AM, OzWhitey said:

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? 

In one of his presentations. Oculus Chief scientist Michael Abrash said: https://uploadvr.com/abrash-2021/

Quote

Finally, the legendary developer talks about depth of focus. This is a much more complicated topic, referring to our eyes’ ability to adjust to focus on different objects at different distances. With current VR, everything appears focused as if you were staring at it from 2 meters away. It’s not a big problem in Abrash’s eyes (quite literally given that he described his eyes to be as limited as the Rift’s display), but it would be “good to fix”.

 

[OzWhitey 3,353]

35 minutes ago, HiFlyer said:

In one of his presentations. Oculus Chief scientist Michael Abrash said: https://uploadvr.com/abrash-2021/

 

I think he's talking about something different here - saying Rift optics are equivalent to focusing a camera 2m from the sensor plane in terms of visual representation.

OP's issue is closest/furthest distance that his eyes can effectively focus on an object, which is a function of the myopia/hypermetropia/emmetropia of the eye PLUS the ability of the individual's eye to accommodate (by making the lens more spherical).

Quote:

With current VR, everything appears focused as if you were staring at it from 2 meters away. It’s not a big problem in Abrash’s eyes (quite literally given that he described his eyes to be as limited as the Rift’s display), but it would be “good to fix”.

Edited July 15, 2020 by OzWhitey

[HiFlyer 9,343]

13 minutes ago, OzWhitey said:

I think he's talking about something different here - saying Rift optics are equivalent to focusing a camera 2m from the sensor plane in terms of visual representation.

OP's issue is closest/furthest distance that his eyes can effectively focus on an object, which is a function of the myopia/hypermetropia/emmetropia of the eye PLUS the ability of the individual's eye to accommodate (by making the lens more spherical).

Quote:

With current VR, everything appears focused as if you were staring at it from 2 meters away. It’s not a big problem in Abrash’s eyes (quite literally given that he described his eyes to be as limited as the Rift’s display), but it would be “good to fix”.

I'm not sure it needs to be all that complicated. I've purchased several different prescription lenses for various VR headsets, and the general rule has always been that if your prescription is for nearsightedness you need glasses or prescription lenses for the headset, and if you are farsighted you usually don't need any additional equipment.

The question I would ask is does the op have a prescription and what type is it, with the expectation being that any additional problems would be taken care of by the prescription.

[OzWhitey 3,353]

1 minute ago, HiFlyer said:

I'm not sure it needs to be all that complicated. I've purchased several different prescription lenses for various VR headsets, and the general rule has always been that if your prescription is for nearsightedness you need glasses or prescription lenses for the headset, and if you are farsighted you usually don't need any additional equipment.

The question I would ask is does the op have a prescription and what type is it, with the expectation being that any additional problems would be taken care of by the prescription.

Well, it’s kind of complicated...

But I was just responding to your post/link, which was talking about a different subject (really more about depth of field).

For the OP’s specific question, the reddit user’s direct experience that i linked is actually more useful to him than theory (it’s actually decent data in this specific instance).

We know that the OP has a prescription already, the question was whether he needs an optical solution!

[HiFlyer 9,343]

14 minutes ago, OzWhitey said:

Well, it’s kind of complicated...

But I was just responding to your post/link, which was talking about a different subject (really more about depth of field).

For the OP’s specific question, the reddit user’s direct experience that i linked is actually more useful to him than theory (it’s actually decent data in this specific instance).

We know that the OP has a prescription already, the question was whether he needs an optical solution!

In real life, I should be using bifocals. But I absolutely hate them, and instead purchase separate glasses for reading and for far distance/driving etc.

One would think that with the vr screen being just inches from my eyes, my reading glasses would be the correct prescription for my vr inserts, but in fact that turned out to be wrong, something I found out the hard way, by purchasing the incorrect lenses. 

It turned out that because the headset default lenses are set to focus at about two meters (to infinity) I actually needed my long distance prescription for VR.

As far as I know, those are the only two parameters that matter when selecting between a lens adapter, or deciding whether to just use glasses. (though I know there are options for prism lenses as well)

Since those are the only available options I'm aware of, the choice seems pretty binary, but perhaps the OP could add additional information?

Edited July 15, 2020 by HiFlyer

[OzWhitey 3,353]

4 minutes ago, HiFlyer said:

In real life, I should be using bifocals. But I absolutely hate them, and instead purchase separate glasses for reading and for far distance/driving etc.

One would think that with the vr screen being just inches from my eyes, my reading glasses would be the correct prescription for my vr inserts, but in fact that turned out to be wrong, something I found out the hard way, by purchasing the incorrect lenses. 

It turned out that because the headset default lenses are set to focus at about two meters (to infinity) I actually needed my long distance prescription for VR.

As far as I know, those are the only two parameters that matter when selecting between a lens adapter, or deciding whether to just use glasses. (though I know there are options for prism lenses as well)

Since those are the only available options I'm aware of, the choice seems pretty binary, but perhaps the OP could add additional information?

No, you do not need to focus from 2m to infinity, you need to focus on a screen at a fixed distance - your eyes are always focusing on the same point, the screen does not move forward or backwards!

You’re applying real world visual concepts to VR, where they don’t apply. 

To answer the question you need to know 2 things - the set distance at which your eyes are focusing in the Rift S - see my Reddit link - and whether the individual can effectively focus a sharp image on their retina at this distance, using cornea and lens. If not - you need to add an extra lens to the system.

[Rbass 27]

20 minutes ago, HiFlyer said:

In real life, I should be using bifocals. But I absolutely hate them, and instead purchase separate glasses for reading and for far distance/driving etc.

One would think that with the vr screen being just inches from my eyes, my reading glasses would be the correct prescription for my vr inserts, but in fact that turned out to be wrong, something I found out the hard way, by purchasing the incorrect lenses. 

It turned out that because the headset default lenses are set to focus at about two meters (to infinity) I actually needed my long distance prescription for VR.

As far as I know, those are the only two parameters that matter when selecting between a lens adapter, or deciding whether to just use glasses. (though I know there are options for prism lenses as well)

Since those are the only available options I'm aware of, the choice seems pretty binary, but perhaps the OP could add additional information?

I recently got my first prescription for progressive lenses, and have to say I really like them. Took a minute to get used to though, but now when flying and driving, where I need to see distance and the instrument panel equally clear, they are awesome. I don’t think they would be appropriate for VR, which prompted my questions. Thanks to the helpful posters here I think I understand the basics now, and can test out my vision at different distances to what lens help, if any, I’d need in a VR headset. 
 

Again appreciate the insights guys.

Edited July 15, 2020 by Rbass

[HiFlyer 9,343]

Just now, OzWhitey said:

No, you do not need to focus from 2m to infinity, you need to focus on a screen at a fixed distance - your eyes are always focusing on the same point, the screen does not move forward or backwards!

We are not speaking the same language, so I'll just stop here.

3 minutes ago, Rbass said:

I don’t think they would be appropriate for VR, which prompted my questions.

I tried those in vr, and it was very distracting. Your mileage may vary.

 

[OzWhitey 3,353]

2 minutes ago, HiFlyer said:

We are not speaking the same language, so I'll just stop here.

 

Hi, the language i am speaking is optics/optometry/ophthalmology, which is something I know a bit about (though it’s 7am and i havent slept yet, so who knows what i am saying). The application of these subjects to VR is interesting. Don’t take offense that i’m pointing out the things you’re saying that are wrong, this is a super-complex subject! 🙂

[mickatmian 52]

8 hours ago, OzWhitey said:

 this is a super-complex subject! 🙂

Only if you make it one! 

Seems simple enough to me but then what would I know I just use my distance glasses which work perfectly for me.

From the VR optician web site: Your far distance prescription (and not your reading or PC prescription

 

 

[OzWhitey 3,353]

1 hour ago, mickatmian said:

Only if you make it one! 

Seems simple enough to me but then what would I know I just use my distance glasses which work perfectly for me.

From the VR optician web site: Your far distance prescription (and not your reading or PC prescription

 

 

No, complex scientific and medical subjects remain complex even if you choose to ignore them!

You can fly a plane without understanding any physics, just accepting that the trees get bigger when you push the yoke forward. But it's not always the ideal way to approach life.

Practically, with respect to VR headsets:

My eye is emmetropic, and like most of the readers here I have a degree of presbyopia. I don't wear glasses, and the Rift S works very well for me. But when I put on my DJI Goggles to fly my drone - and look at an object apparently 100 metres away - the image is blurry. What's going on here? An average optometrist, who does not understand VR headsets, might to struggle to explain this. But if I wear a +1.50 diopter lens, the headset image becomes sharp, which actually makes perfect sense if you understand what I posted above.

TL;DR Understanding science and medicine is sometimes helpful! 🙂

 

Edited July 16, 2020 by OzWhitey

[whitav8 98]

I simply gave WidMovr my entire current optometrist prescription and they figure out what is correct for their lenses. 

 

Example

O.D.    -2.00    -2.00    93    +2.50
O.S.    -2.75    -2.25    88        IPD = 64.5

[HiFlyer 9,343]

Alrighty then!!

 

[spnd 0]

This was and interesting read and what I have discovered is that VR Glasses use a lens to change the close image to be focused at infinity and this applies to all objects in view.  For those like me who need glasses for distance vision, they are required in VR to bring your vision into the "normal" range, so you can wear your glasses or buy prescription inserts.  The bi-focal portion of your vision accommodates for the inability of your lens to focus near objects but this is not necessary for VR because they are all focused to infinity.  Found this short video that shows how this is ac accomplished in VR.  https://vr-lens-lab.com/lenses-for-virtual-reality-headsets/