New To The Forum? Click Here To Read The How To Guide. -- Developers Click Here.

Getting the right prescription for lens inserts or Go dedicated glasses

voxelmaniamvoxelmaniam Posts: 85
Hiro Protagonist
This thread is a continuation of one started by user haydon.sheppard here:
https://forums.oculusvr.com/community/discussion/comment/613239#Comment_613239

Summary
Not everyone has the best visual experience when first strapping on the Oculus Go. Some users are reporting an inability to get a clear, focused image on the Go display. Barring some fault in a specific Go's assembly most if not all of the focus issues boil down to one or a combination of four things.
1) The Go headset is incorrectly positioned in front of the users eyes.
2) The media content that is being viewed is out of focus or low resolution and thus appears blurry.
3) The user's eyes require corrective lenses and they are not being worn.
4) The corrective lens inserts or glasses worn by the user are unsuited to the optical working distance of the Go.

This discussion will focus on item 4.
The Go can be worn comfortably with glasses but depending upon an individual's prescription a particular set of glasses may not work well with the Go's optics. The case in point that has been under discussion in the thread mentioned above is where the prescription being worn contains a progressive or no-line bifocal configuration and the user's eyes also have fixed focus lens implants as a result of cataract surgery. The particular lenses being worn allow a mixture of focal distances depending upon the vertical angle of view: Straight ahead - distance focus, angled down - near focus. Along with other factors related to the manufacture of progressive optics this causes a significant narrowing of the visual field that can be seen in focus. This means that the eyes can't be rotated to see other parts of the scene. Rather the head must be rotated to see other parts of the scene in focus, for example when reading across the page in the browser.

The solution to this problem is to get single focus glasses. However, for for optimum performance with the Go they should be prescribed for the Go's optical working distance. That is the apparent distance that the Go's optics simulate when when you look through them. For a young person that requires corrective glasses, with natural lenses in their eyes, the distance vision correction prescribed by the eye doctor is sufficient because their eyes can accommodate to the Go's optical working distance. For older users such as myself and particularly because I have fixed focus lens implants, a prescription must be calculated specifically for the Go's optical working distance.

My quest for the right prescription started with my eye doctor. He said that he would have to know more about the Go's optical working distance to write a prescription. I then went to Frames Direct, Oculus' provider of choice for lens inserts. They said they didn't have that information, they worked only with the distance vision prescription and referred me to Oculus support. At first Oculus support referred me to my eye doctor and Frames Direct but with additional (repeated) explanation they are looking deeper (higher) for information about the Go's optical working distance. Cybereality has suggested that the optical working distance is in the range from 1 to 1.5 meters. I'm hoping for something a bit more precise, say within plus or minus 1 inch.

Stay tuned...
A voxel is a three dimensional pixel!
Murray Foster
«1

Comments

  • haydon.sheppardhaydon.sheppard Posts: 22
    NerveGear
    Nicely put Murray. I am eager to know what they have to say. Also a little suprised they did not foresee this scenario and be better prepared.
  • voxelmaniamvoxelmaniam Posts: 85
    Hiro Protagonist
    Thanks!
    A voxel is a three dimensional pixel!
    Murray Foster
  • TwoHedWlfTwoHedWlf Posts: 2,032 Poster of the Week
    I don't think it's possible to give you a focal distance down to the inch, it will vary depending on things like how tight it is on your face, the shape of your head, depth of your eyes, all of that effects the position of your eyes and by that exact focal distance.
  • JustBob12JustBob12 Posts: 14
    NerveGear
    I wear progressives and the "sweet spot" is hard to find and I struggle to get a clear image. It's not bad, but I think it could be better. I tried a pair of reading glasses and they were useless. Then after reading your post, I tried a another pair I use to play tennis which only have the distance prescription. Oddly enough, the stuff that seems closer to you (the bottom menu bar is a good example) seemed easier to read than with my full prescription glasses. Everything else (I tried video clips, Netflix, game...) seemed similar to what I see with the full prescription glasses. My distance prescription glasses (the tennis ones) are older though and the prescription isn't up to date. 

    I'm due for an eye exam anyway (last was 2015) so I'll see if I need new glasses. If I need new glasses, I'll be curious to compare the new full prescription with the new distance only glasses.

    Thanks for this post, very interesting.
  • voxelmaniamvoxelmaniam Posts: 85
    Hiro Protagonist
    TwoHedWlf said:
    I don't think it's possible to give you a focal distance down to the inch, it will vary depending on things like how tight it is on your face, the shape of your head, depth of your eyes, all of that effects the position of your eyes and by that exact focal distance.
    I suspect that the Go's optics were designed to produce a precise working distance based on the display position and a precise eye position. What the eye perceives as being in focus lies on a range of distances from the eye. Also, the majority of users have the ability to adjust there eye focus. I don't have that ability in my eye due to fixed focus implants. So there is some latitude in the eye position but starting with the precise parameters will allow for a more appropriate corrective lens for my eyes. 

    A voxel is a three dimensional pixel!
    Murray Foster
  • brentonibrentoni Posts: 18
    NerveGear
    JustBob12 said:
    I wear progressives and the "sweet spot" is hard to find and I struggle to get a clear image. It's not bad, but I think it could be better. I tried a pair of reading glasses and they were useless. Then after reading your post, I tried a another pair I use to play tennis which only have the distance prescription. Oddly enough, the stuff that seems closer to you (the bottom menu bar is a good example) seemed easier to read than with my full prescription glasses. Everything else (I tried video clips, Netflix, game...) seemed similar to what I see with the full prescription glasses. My distance prescription glasses (the tennis ones) are older though and the prescription isn't up to date. 

    I'm due for an eye exam anyway (last was 2015) so I'll see if I need new glasses. If I need new glasses, I'll be curious to compare the new full prescription with the new distance only glasses.

    Thanks for this post, very interesting.
    I suspect that the reason glasses with distance prescription worked for stuff that is up close is because the distance that things appear in the Go has little to do with the actual focal distance of the Go. Basically the distances between the screen, the lenses and your eyes, as well as the strength of the lenses creates a specific focal distance your eyes are always focused at while wearing the Go, and anytime something appears to be at a different distance it is actually an illusion caused by showing each eye a different image and doesn't actually affect the focal distance. The reason your distance lenses were better for the bottom menu but the same as progressives for stuff that looked further away is probably because you were trying to read with the near vision part of your lenses when you actually need to be using distance vision for everything.
  • voxelmaniamvoxelmaniam Posts: 85
    Hiro Protagonist
    brentoni said:
    I suspect that the reason glasses with distance prescription worked for stuff that is up close is because the distance that things appear in the Go has little to do with the actual focal distance of the Go. Basically the distances between the screen, the lenses and your eyes, as well as the strength of the lenses creates a specific focal distance your eyes are always focused at while wearing the Go, and anytime something appears to be at a different distance it is actually an illusion caused by showing each eye a different image and doesn't actually affect the focal distance. The reason your distance lenses were better for the bottom menu but the same as progressives for stuff that looked further away is probably because you were trying to read with the near vision part of your lenses when you actually need to be using distance vision for everything.
    Yes, the focal distance is the same for all of the images displayed in the Go. The stereo pairs are designed so that the eye sees objects that are intended to appear closer with a larger offset towards the center of the scene. This results in the eyes having a larger angular deviation towards the center and as a result the objects are perceived as being closer.
    A voxel is a three dimensional pixel!
    Murray Foster
  • haydon.sheppardhaydon.sheppard Posts: 22
    NerveGear
    Still no definitive answer Murray?
  • voxelmaniamvoxelmaniam Posts: 85
    Hiro Protagonist
    brentoni said:
    I suspect that the reason glasses with distance prescription worked for stuff that is up close is because the distance that things appear in the Go has little to do with the actual focal distance of the Go. Basically the distances between the screen, the lenses and your eyes, as well as the strength of the lenses creates a specific focal distance your eyes are always focused at while wearing the Go, and anytime something appears to be at a different distance it is actually an illusion caused by showing each eye a different image and doesn't actually affect the focal distance. The reason your distance lenses were better for the bottom menu but the same as progressives for stuff that looked further away is probably because you were trying to read with the near vision part of your lenses when you actually need to be using distance vision for everything.
    Yes, the focal distance is the same for all of the images displayed in the Go. The stereo pairs are designed so that the eye sees objects that are intended to appear closer with a larger offset towards the center of the scene. This results in the eyes having a larger angular deviation towards the center and as a result the objects are perceived as being closer.
    A voxel is a three dimensional pixel!
    Murray Foster
  • voxelmaniamvoxelmaniam Posts: 85
    Hiro Protagonist
    Still no definitive answer Murray?
    I pinged Oculus support yesterday after not hearing anything for 4 days. I was told they are still looking into an answer for my question. I really don't understand why it is such a mystery. But given that it does intersect with the subject of eye health it may not be something they want to treat with an off the cuff answer.
    A voxel is a three dimensional pixel!
    Murray Foster
  • haydon.sheppardhaydon.sheppard Posts: 22
    NerveGear
    Well Murray. I hope the answer is worth the waiting for. Lol.
    I’m still interested to know how I approach an Optician with a request for single vision glasses for the Go and how they even think about conducting an eye test on that basis?
    Anyone else reading this encountered this scenario yet?
  • RoasterRoaster Posts: 1,036
    3Jane
    I can tell you my experience.  I have a pair of glasses with a single distance grind measured for 24", mainy intended for computer use.  They work perfectly with both the Rift and Go.  Progressive bi-focals would be the worst choice, for the same reason you might tilt your head back and look through the lower part of the lens to get a good focus on your pc screen.  You can't do that with a headset on which moves with your head angle.
    For some users the main benefit of prescription glasses is correction of astigmatism, which for the uninformed will manifest itself as a warping of the perspective, usually with a cylindrical lens effect instead of the normal spherical surface.  With my pc glasses everything in the Go is tack sharp.
    i7-5820K @ 4.2Ghz, water cooled, Asus X99-Pro USB 3.1, 48 Gb DDR4 2400, Samsung 950 pro M.2 SSD, GTX 980 Ti SC, 750w psu
  • voxelmaniamvoxelmaniam Posts: 85
    Hiro Protagonist
    Wish that I had something to report but I haven't heard word one out of Oculus. I even copied John Carmack without result. I'm glad to hear Roaster's results but I think I'm going to be patient and see if any thing comes from Oculus. In the meantime I've gone back to my optician and asked them to give me the single vision calculation for the monitor distance glasses that I purchased last year. I then purchased an inexpensive pair of single focus glasses. They are an improvement over the progressives but I still feel that I could do better. I may eventually go for the inserts. I also have to face the reality that I have significant vision lose in both eyes and my experience is never going to be as good as someone with 20/20 vision and perfect fields.
    A voxel is a three dimensional pixel!
    Murray Foster
  • TwoHedWlfTwoHedWlf Posts: 2,032 Poster of the Week
    The best solution might be to get lasik.  I'm thinking about it.  I can afford the $6000 it costs, but...The idea of laying there while someone shoots lasers and then peels a big chunk of eyeball back so they can shoot more lasers...

    Kinda freaks me the fuck out.
  • voxelmaniamvoxelmaniam Posts: 85
    Hiro Protagonist
    edited June 9
    LASIK isn’t an option once you have lens implants.
    A voxel is a three dimensional pixel!
    Murray Foster
  • haydon.sheppardhaydon.sheppard Posts: 22
    NerveGear
    I’m off to the opticians in a few days to get a single vision prescription for the Go. Not sure what reception I will get. All seems a bit hit and miss. I will take the Go along.  I presume I don’t need wi-fi to get some sort of display up?
    i can’t believe that Murray is still waiting to an answer from Oculus about the viewing distance! 
    I will relay back my experiences. Anyone already gone through this process?
  • haydon.sheppardhaydon.sheppard Posts: 22
    NerveGear
    sorry if this has already appeared in another forum
  • haydon.sheppardhaydon.sheppard Posts: 22
    NerveGear
    Just seen the WidmoVR prescription lenses. Sounds like a perfect solution but it all rests on getting the right prescription in the first place. Ie. What viewing distance does your optician use for the Go?
  • voxelmaniamvoxelmaniam Posts: 85
    Hiro Protagonist
    Just seen the WidmoVR prescription lenses. Sounds like a perfect solution but it all rests on getting the right prescription in the first place. Ie. What viewing distance does your optician use for the Go?
    I'm not sure if you are addressing me or someone else. The computer glasses are for right around 24" although I don't recall that they stated a specific distance. Apparently they have a standard calculation for computer glasses but my working distance is right around 24" to 26". The range for acceptable focus for me seems to be from about 18" to 32" with the fuzzes setting in closer and further than that range. However, I'm beginning to feel that I should have a pair of glasses made with my distance focus values + astigmatism correction. WidmoVR told me that was the prescription that they wanted even after I told them about all of my issues.
    A voxel is a three dimensional pixel!
    Murray Foster
  • haydon.sheppardhaydon.sheppard Posts: 22
    NerveGear
    edited June 11
    Sorry Murray. Not used to these forum things. Lol. Yes it was directed to you. Thanks for you’re reply. Is it worth me contacting WimoVR? I’m now even more confused about the viewing distance for the Go. I just think my trip to the Opticians will be trial and error until we find the sweet spot. At least it’s a free eye test.
  • voxelmaniamvoxelmaniam Posts: 85
    Hiro Protagonist
    Sorry Murray. Not used to these forum things. Lol. Yes it was directed to you. Thanks for you’re reply. Is it worth me contacting WimoVR? I’m now even more confused about the viewing distance for the Go. I just think my trip to the Opticians will be trial and error until we find the sweet spot. At least it’s a free eye test.

    No problem. As I mentioned, after explaining my eye issues WimoVR said the distance vision prescription was what they used. It certainly can't hurt to ask.

    At this point it seems like I'm left to trial and error to find out what works best. My next move is going to be ordering a pair of glasses online from Zenni Optical that are my single vision distance prescription. I can get them without any bells or whistles for about $17. This will give me another data point. If they give me good results then I will probably spring for the inserts because their positioning will probably allow them to give the best field of view. I will keep you posted.
    A voxel is a three dimensional pixel!
    Murray Foster
  • RavengerRavenger Posts: 33
    Brain Burst
    I find funnily enough that my VDU distance glasses (about 1m/3 feet focus) seem to work better than my distance glasses with the Go. It just seems less straining on my eyes, and I find the focus is sharp enough to actually make out the display pixels if I look for them. I have WidmoVR lenses for my Rift with a distance perscription and they are fine, good focus with no eye-strain. If I use my VDU glasses they are less clear. So it seems to me the Go's focus distance is closer than the Rift's (though of course I could be wrong). The Go's fixed IPD may also be a factor.
  • haydon.sheppardhaydon.sheppard Posts: 22
    NerveGear
    edited June 12
    Thanks Murray and Ravenger for your input. I will update this forum with my findings after the visit to the optician. If you don’t mind I have one final question? My viewing experience on the Go is a narrowish centre portion which is reasonably in focus with upper and lower parts of the screen blurry. Also if I glance left and right the image is also blurry. I am assuming this effect is a result of my variofocals. Can anyone else wearing variofocals confirm this? Thanks.
  • RavengerRavenger Posts: 33
    Brain Burst
    It's not a varifocal issue - it's a natural consequence of the way VR lenses work. There's always an in-focus 'sweet spot' in the middle and blurrier edges with chromatic aberration (However the Rift compensates for Chromatic aberration, the Go doesn't, due to the GPU power required).

    However wearing Varifocals will make the image even more blurry with a smaller sweet-spot, due to the graduated focus distance in the varifocal lens. You need to wear fixed focus glasses with the Go and the Rift. However what the actual focus distance actually is has not been revealed by Oculus officially. Most people find their distance prescription works just fine.

    One of the benefits with the fixed focus distance in VR is that people like me with age-related Presbyopia (long sight due to lens inflexibility) can read things up close without having to switch glasses or wear varifocals. B)
  • voxelmaniamvoxelmaniam Posts: 85
    Hiro Protagonist
    I've received some information about this in a private communication. I've asked for permission to post it to the forum but haven't heard back yet. However, based on the content of the message I think the distance vision prescription is the best choice for now. Ravenger, what does VDU stand for?
    A voxel is a three dimensional pixel!
    Murray Foster
  • voxelmaniamvoxelmaniam Posts: 85
    Hiro Protagonist
    edited June 14
    The targeted focal distance at the center of the frame for Oculus Go is 1.3 meters. The focal plane of the virtual image is not a flat surface but a curved surface, so the focal distance varies based on factors like eye rotation, the visual field and manufacturing tolerance.

    So this is the information we have been seeking. At 1.3 meters (~51 inches) I think we are getting into distance vision territory. I will be seeing my ophthalmologist on Monday and I will get him to advise based on this information.
    A voxel is a three dimensional pixel!
    Murray Foster
  • haydon.sheppardhaydon.sheppard Posts: 22
    NerveGear
    edited June 16
    I hope the following will be useful to those of you considering prescription single vision glasses for the Go.
    i visited my local Boots optician here in the UK yesterday and explained my requirements. This was the first time they had dealt with this sort of request so was not straightforward. I undertook the normal eye test for my variofocals but later explained it was specifically single vision for the Go I required. This presented a few challenges. Working with the 1.3m focal distance supplied by Oculus the optician did his best to work out a prescription but I was unable to use their device whereby you can slip lenses in and out of their device due to it being too big to fit inside the headset. This left us with no alternative but to measure the focal distance with a tape measure and use posters on the wall with different size type to establish roughly the prescription.
    Previously with my variofocals the centre portion has always been the best viewing experience so that’s what we settled for. Still a bit hit and miss but they did explain that there was a certain amount of tolerance behind and in front of the optimum viewing distance.
    So, where do I go from here? If I buy from Boots the minimum the glasses will cost is about £70 but I have the flexibility to be able to return to them if they prescription needs tweaking. I have to say the optician was brilliant.
    I have decided to order online with Glassesdirect which will cost me £35. They have a 7 day return policy so I’m prepared to take the chance. I did consider WidmoVR but it’s a lot to risk if the prescription is not accurate. 
    I hope this will be helpful to others and am happy to answer any questions I may not have covered. When I receive my online glasses I will post an update.
  • RavengerRavenger Posts: 33
    Brain Burst
    Ravenger, what does VDU stand for?
    Visual Display Unit, or more colloquially, a computer screen.
  • RavengerRavenger Posts: 33
    Brain Burst
    Thanks for the info that the focus distance is 1.3m, so that would explain why I find my computer glasses with a 1m focus distance more comfortable than my distance glasses.
  • voxelmaniamvoxelmaniam Posts: 85
    Hiro Protagonist
    Ravenger said:
    Ravenger, what does VDU stand for?
    Visual Display Unit, or more colloquially, a computer screen.
    Suspected that to be the meaning but I didn't want to assume. Could have been some esoteric device that I hadn't yet encountered.
    A voxel is a three dimensional pixel!
    Murray Foster
«1
Sign In or Register to comment.