IPD. It stands for “Inter-Pupillary Distance,” but I’m going to keep saying IPD. It’s just easier that way.
Maybe you’ve heard of it, maybe you haven’t. What everybody interested in VR should know is that it is a very big deal. The most valid concern you could have regarding IPD is whether or not your VR headset is going to have an IPD compatible with yours.
In this article, I will be providing a basic, as well as detailed, introduction to IPD. I’ll also be talking about why it’s important to know about, especially in a virtual reality context.
If you already know your IPD, head on over to the end of the article to see the IPD specifications for a variety of headsets.
IPD: THE BASICS
Simply put: IPD refers to the distance between the centers of the eyes.
“What does that have to do with VR?” It’s important for the lenses of your VR headset to be correctly aligned with your eyes. Matching your IPD to what your headset supports is necessary to maximize the experience!
Now let’s talk in fancy words for a bit.
IPD: A LITTLE MORE THAN BASICS
The average IPD for us (yes, humans) is 64mm. This figure can range anywhere from 54mm to 72mm, and you would still be considered pretty normal.
So what exactly does not caring about IPD do to you?
Suppose you’re wearing regular reading glasses. Each eye is looking through a separate lens. If your eyes are not in line with the optical center of the lens, then the light that enters your retina is going to be reflected wrong. This is what commonly causes headaches and eye strain.
Using a VR headset is not so different from this example. You depend on the lenses in your headset to show you the journey that VR promises!
With the science having been talked about, here are some general fun facts about IPD!
- The distance is very unlikely to be the same for any two people.
- IPD increases when you’re focusing on something that’s far away, and it reduces as you look at something closer (because your eyes come closer together).
So how exactly is your IPD going to impact your VR experience?
WHY IPD MATTERS IN VR
When you’re trying to trick your brain into thinking you’re in the VR world, you’re going to want to make sure that you show it the right things. You need to believe what the lenses in the headset are showing you. Using a headset that matches your IPD is what will make the experience worthwhile.
“What happens if there’s an IPD mismatch?” Well for starters, you won’t be seeing the game (or movie) right. A part of the “screen” would appear cut off to you. Think of how annoying it is watching TV or videos on your phone with those thick black lines around the screen. And it gets worse!
Not only will you be subjecting yourself to eye strain, but your perceptions of the VR experience are going to be off. More so than it looks off, something about what you’re seeing just won’t feel right to your mind.
Depth and distance perceptions are crucial to immersion. If your brain can’t believe what it sees, you’re missing out on using your VR setup to its full potential.
If you’re wondering how common IPD problems are, you don’t need to worry too much. Pretty much every headset fits well for users with average IPDs. The good news is that developers are increasingly recognizing the importance of designing headsets with manually-adjustable IPD settings!
But since I care about you, and the future of VR, I am going to want you to be confident that your configurations are exactly how you want them to be!
To learn how you can avoid an IPD mismatch with your VR setup, look no further than this article! It’s as simple as doing two steps:
HOW TO MEASURE IPD FOR VR
Before you start looking at the IPD’s different headsets are suited for, you’ll need to know your own, so that you know what number you’re looking for. Here are some ways to do this:
- Using a ruler and a mirror. Check out step-by-step instructions for this method.
- Consult an optician. If you’ve already been visiting one, there’s a good chance that your IPD is mentioned in one of your documents already!
- Visit any glasses or lenses shop. Most of them will have the necessary equipment, and (most likely) the expertise to measure your IPD.
- Download the free iOS app “EyeMeasure.” The app has been reported to give you an IPD measure with only a 0.5mm deviation. When using the app, go for the “far” IPD measurement for an ideal number to compare with your VR headset.
- Use online IPD measurement tools. You’ll be asked to upload a picture of yourself holding an item with a magnetic strip (usually ID cards or credit cards). The item you use becomes a scale for measurement.
- Figure it out on your own. This is by far the least accurate measure, and it only works if you’re using a VR headset that can be manually adjusted for IPD. It works by simply closing your non-dominant eye while wearing the headset. Then all you have to do is focus on an object, and adjust the headset until the sharpness of the object you’re seeing is at its best.
If there’s more than one person who uses the headset, it would be a good idea to have everybody know their IPDs. You can then change IPD settings as required on a player-by-player basis!
Now that you’ve got your personal IPD down, it’s time to find out what range is supported by your VR headset. Here’s step two!
POPULAR VR HEADSET IPD RANGES
Not all headsets come with the option to manually adjust their IPD. It’s quite a bummer when different people with varying IPDs are using the same headset.
However, you’ll notice that most headsets contain a software IPD adjustment feature. This handy little feature allows the headset to automatically change its settings to best match the IPD of the user.
Here’s some useful IPD information for various headsets. Headsets with software adjustments are marked with an asterisk (*):
|Headset||IPD Range (mm)||Ideal User IPD (mm)||Manual Adjustment Possibility|
|Oculus Rift||58 – 72||56 – 74||Yes|
|* Oculus Rift S||63.5||61.5 – 65.5||No|
|Oculus Go||63.5||61.5 – 65.5||No|
|Oculus Quest||58 – 72||56 – 74||Yes|
|Oculus Quest 2||58-68||56-70||Yes|
|Oculus Rift CV1||58 – 72||56 – 70||Yes|
|Samsung Odyssy+||60 – 72||58 – 74||Yes|
|HTC Vive||60 – 74||58 – 74||Yes|
|HTC Vive Pro||60.7 – 73.5||58.7 – 75.5||Yes|
|*PIMAX 4K||58 – 71||58 – 71||No|
|*PIMAX 5K+||60 – 73||55 – 75||No|
|*PIMAX 5K XR||60 – 70||50 – 80||Yes|
|*PIMAX 8K||60 -73||55 – 75||No|
|*PIMAX Artisan||60 – 72||55 – 75||No|
|*HP Reverb||63||55 – 71||No|
|HP Reverb G2||60 – 68||58 – 70||Yes|
|*ACER WMR||63||59 – 67||No|
|Lenovo WMR||63||62 – 64||Yes|
|Valve Index||58 – 70||60 – 68||Yes|
|*PSVR||57 – 71||– 68||No|
|*XTAL||56 – 76||58 – 72||No|
Changing IPD settings through built-in software is the go-to choice for some people. After all, letting a computer do all the work sounds easy enough. Others tend to find this method rather time-consuming.
When there’s many people using the same headset, a hardware option for changing IPD is recommended. It’s faster, easy to configure, and works just as well as having a software do it!
So what’s the best headset for your IPD?