Yesterday here in Silicon Valley I was amazed to discover a new product that may have solved one of the biggest problems of public VR demos. I was introduced to it by George Zhao, the CEO of VOY Glasses, who showed me his tunable prescription lenses.
The prescription lenses issue
Wearing your glasses inside VR headsets is never comfortable: it got better over the years (Meta Quest ships with a glass distancer to improve your comfort when you have glasses), but it has never become a pleasant experience. Luckily there are companies offering prescription lenses for the XR headsets: these products are inserts that you attach on top of the lenses of your headset and that feature a lens that is able to adjust the visuals for your eye parameters. They are usually quite good, but they have the problem that they are customized for your eye prescriptions. If you are buying them for a headset you just use by yourself, than they are amazing, but they are a bit more problematic for headsets that operate in shared settings.
If the VR headset is shared by all the people of a family, for instance, you have to keep swapping prescription inserts depending on who uses the device, which is a mess. In enterprise settings, you have the same problem if multiple people have to use the same headset for training. When you do public demos, “Can I keep my glasses?” is a typical question that you hear from people trying your experience at exhibitions. Carrying with you a suitcase full of prescription lenses and installing them (and sanitizing them…) for every person coming to your booth, is going to be very time-consuming. So usually during public demos, companies never use prescription lenses, and let people keep their glasses inside the headset, for a sub-optimal experience.
VOY Glasses tunable inserts
VOY Glasses is able to solve this problem with a prescription lens to rule them all: it is an insert that you put on the lens of your headset, exactly like all the other ones currently on the market, but with a slider that lets you select your prescription. This means that you have just to install two “tunable” prescription lenses, one per eye, and then every person using the headset has just to select what are its prescription values to use the device with maximum comfort.
The slider is mechanical and has a range of 6 prescription values. Mr. Zhao told me that currently there are two versions of the lenses: from 0 to -6 (for myopia only) and from -3 to +3 (to cover both myopia and presbyopia). He said that with the myopia range, the lenses can cover 80% of the population with this impairment. The slider through which you change the optical parameters offers continuous prescription values: so if you put it between -2 and -3, it will have -2.5 as the prescription value.
I was amazed by how this idea looked so simple but at the same time so useful. Thanks to this gadget, it is possible to make VR demos in a much more streamlined way: you just have to ask your visitor what are his eye parameters, set them on the fly with a slider, and then put the headset on his head. And for hygiene, you just have to clean the same prescription lens. It’s literally amazing.
How does it work?
Mr. Zhao has been able to create this device because he’s an optical expert with many years of experience. He realized that we have been using the same lens form factor for many years, and he wanted to innovate this.
He used an optical principle developed independently by Luis Alvarez and Adolph Lohmann which says that if you create two parallel lenses with a special form factor (the surface looks a bit like a sea wave), the compound of the two lenses will be like a lens with different parameters depending on the relative position of the lenses. That is: if you slide one of the two lenses, the “resulting lens” of the whole optical system will change its focal distance.
George told me that he started from this principle and innovated on top of it, creating a patented technology he uses in his lenses. But the basic principle is the same: there is one lens that is fixed inside the frame of the insert, and then there is another lens that moves while you move the slider. When the movable lens moves, it changes the focus of the optical system, going to correct different prescription values.
He also told me that creating such a system is not easy and it requires special machines with nanometric precision. Without this accuracy, the lens system is not going to have the quality that is needed to provide great vision quality to the user.
The present and the future
VOY Glasses inserts are currently available for a few headsets from Meta and Lenovo. The company is evaluating to create accessories also for other accessories, like the Apple Vision Pro.
Everyone can buy these gadgets, and the company is evaluating both the consumer and the enterprise use cases. Regarding the enterprise, VOY has the intention of collaborating with distributors that may take care of all the necessary services (e.g. customer assistance, fast replacement, etc…) that are usually provided in the B2B sector. VOY just wants to keep doing what it is good at doing (that is making optical systems) and leaving the rest to companies that are specialized in it.
Regarding some possible future projections, I think it would be cool if one day such a lens is connected to the eye-tracking system of the device. If eye tracking cameras are able to automatically detect what is more or less the eye prescription of the user, the headset may automatically set the IPD and the eye prescription values during the eye calibration procedure. I don’t know when something like this would be possible, but it could improve a lot the usability of XR headsets in public settings.
Cost and availability
VOY Glasses inserts are currently available on its website: the ones for Meta Quest 2 and Meta Quest 3 cost $59, while the set for the Lenovo ThindReality VRX is priced at $69.
Hands-on
I played a bit with VOY Glasses inserts and my Quest 3 and so I can express my first impressions about them.
The setup is rather easy, you just have to align the insert shape to the headset lens shape and then press the insert until it clicks. The first time I did it, I had some difficulties in understanding what was the right alignment, but after I did it the first time, I managed to do that other times without many issues. Once they are attached, they are rather stable: I tried to put my headset on and off for 10 times in a row, making also the inserts collide with my forehead, but they did not detach. This is good.
Detaching them on purpose is instead very easy: you have to pull the gadget while gently rotating it and it will detach without any problem.
The lenses seemed well-made, and the slider worked without issues. I’m anyway a bit concerned about what happens if you move the slider hundreds of times in a day, like during a typical expo day, because I’m afraid it could loosen up a bit. I moved it a few dozen times and it is still stiff, so it has some resistance, but to test its quality it should be tested in a real exhibition scenario.
The lenses are transparent and have some greenish reflections, so they also filter some blue radiation, I guess. I was thinking that depending on the position of my eye relative to the lens, the optical parameters would change, but this is not the case. Once the two lenses are in a certain position, they create an optical system that is like a single lens, it is not that depending on where you put the eye you have a different focal distance. I have no eye impairments, so I can not judge the optical parameters correction, but I can still evaluate how they work at the position “0”.
Installing them on my Quest, I saw that more or less the optical parameters seem unchanged at first sight: the FOV and the clarity of the display look the same with or without the insert. But at a deeper analysis, I noticed two little issues: first of all, they create a slight warping in the periphery of the vision, so when you rotate your head, you slightly notice that something is getting deformed. It is not a big effect and does not ruin the overall experience, but it is noticeable. Second, the clarity at the periphery of the vision is slightly degraded as well: I tried to read some text at my far right with and without lenses, and with the prescription, it was a bit more blurred. Again, this is not a major issue, but it is worth reporting.
There is also a little problem with comfort. These lens systems are a bit thick and when you wear them, you feel their border close to your eye and forehead bones. George told me that to avoid this you must wear the glasses spacer of the headset (it is even written in the installation instructions), but I don’t have it with me so I can not test this. This is a problem with other VR prescription lenses, but these ones are slightly thicker because they have to host two lenses, so the comfort is slightly worse than the others that I’ve tried.
Final impressions
I’ve been pleasantly surprised by VOY Glasses prescription lenses: they are able to provide a very handy solution for guaranteeing a better experience to VR users in settings where multiple people use the same headset, like inside company training programs or VR exhibitions. The product is useful, solid, and has an affordable price. There are some little issues but to me, they don’t ruin the overall VR experience, especially if we are considering the short time of a demo in an event. I think this device is something that adds value to our ecosystem.
If you will be at AWE, you should know that VOY will have a booth there, so you will be able to try this product with your own eyes. I suggest you give it a try because it’s a very interesting gadget.