There are a lot of posts out there that talks about the best VR headset we can buy now. However, have you ever questioned: What makes a great VR headset? The one which is very popular in the market now is really a great one? In order to have the answer, we should have a look at the factors of a VR headset.
Before starting this topic, let’s have a look back types of virtual reality headset we have at the moment, that I also mentioned in the last article.
- Mobile VR headset: We have VR headsets, and in order to experience virtual reality, we still need a smartphone with VR applications installed on its.
- Standalone VR headset (or also called all-in-one VR device): We no need any smartphone here, since it has a built-in system right on it. This type of VR headset is very convenient in use.
- Home VR headset (or PC-VR headset): With this type of headset, we will need a PC in order to experience virtual reality.
Ok, now we know which VR headset we should to choose for our use, then what next should we pay attention to before deciding to buy since now there are a lot of VR headsets in the market, from expensive to very cheap!
Lots of articles talk about the best VR headset, but we still don’t know why they are the best ones, but we still believe in them, because they are from tech giants or famous brands. It is sure that those tech giants can bring the best things, in a usual way, but there are still lots of other VR headsets in the market, but they are not from those giants or have big brands. Then they are not so good? If you think so, it is not fair at all!
Lenses of VR headset
I think that this should be the first thing we should care about when we concern about a VR headset. The lenses of a VR headset is special and different from others!
At first, why we need lenses on our VR headset? Our eyes have built-in lenses, but it becomes older when we grow up, and because of the eyes age, the lenses also become less able to band and alter the incoming light, then this is why teenagers can focus on things as close as 7 cm in front of their eyes, but older people cannot.
When wearing a virtual reality headset, the distance is kind of short (usually 3 to 7 cm in front of our eyes), and we humans have difficulty watching things inside the headset. That’s why we need lenses in a VR headset, which bend the light and make it easier for our eyes to see.
According to VR Lens Lab: If your eyes focus on something far away, they focus on infinity. That means the rays of light are parallel and the lenses of your eyes are relaxed. If an object like this little fly moves closer to your eyes and you want to keep it in focus your lens bends and breaks the light differently. To keep the fly in focus all the light from a single point on the insect needs to be focused on a single point in the back of your eyes. If the fly comes too close the lens cannot bend enough and you lose focus. This is why VR HMDs need special lenses, so the angle of the light from the lenses is corrected so that it can be used by our eyes again.
Usually, in order to make the headset thinner and lighter, some VR headsets are designed with Fresnel lenses. This type of lens is the same with curvature as regular lenses but they are segmented. When using Fresnel lenses, we can create lenses with many segments, which results in a sharper image, but we will lose light that gets scattered at the peaks that do not have the right curvature. Of course, we also can create Fresnel lenses that have fewer segments that can bring us a result with less scattered light and more contrast, but this also can bring us images that aren’t as sharp.
Another option for our VR headset is that Aspherical lenses, that are not segmented, but this is thicker, and also makes our VR headset bigger. We can use thicker lenses (with a shorter focal length for a stronger magnification) and move the display closer but those thicker lenses add new engineering challenges to keep geometric distortion and chromatic aberration under control. Due to the stronger magnification, a higher resolution display is needed as well to avoid or reduce the screendoor effect (in which we see individual pixels).
Field of View
Field of view, or the extent of the observable environment at any given time, is one of the more important aspects of virtual reality. The wider the field of view, the more present the user is likely to feel in the experience. Or we also can say that: The wider the FOV, the better VR experience we have.
The FOV is also decided by the type of lens we have with our VR headset.
What is refresh rate? The refresh rate (most commonly the "vertical refresh rate", "vertical scan rate" for cathode ray tubes) is the number of times for a second that a display hardware updates its buffer. This is distinct from the measure of frame rate in that the refresh rate includes the repeated drawing of identical frames, while frame rate measures how often a video source can feed an entire frame of new data to a display.
The higher refresh rate VR headset has, the better experience and the less VR sickness we get! At the moment, most of our VR headset can offer us a refresh rate at 60Hz, but few others have better one (90Hz or even 120Hz). If we can have a VR headset with a 120Hz refresh rate, this is super great for our virtual reality experience. I also hope that can have more higher refresh rate VR headsets in the near future.
Virtual reality require a very high definition so that we can have a better experience. Then, the screen of a VR headset usually have at least 1080p resolution. However, in order to have a really great experience with VR, we need an ultra-high-resolution screen! Then many companies are working on this to make it real! We also can see there is some 4K VR headsets in the market, and even PiMax is working on 8K VR headset. But most of them are still quite expensive. The company I am working for is also developing a 4K VR headset, an all-in-one VR device with dual 3D cameras in the front. We will launch this version very soon!
We have to wear the headset on to experience, then we will want it as light as possible! But that is still not enough!
To wear a VR headset for hours, we also have to consider about the materials of the headset, especially the part contacts our face. This part must be soft, flexible, and can deal with the oil skin problem. Besides, the headset should have straps to fix on our head, not something like Google Cardboard that we have to use our hands to hold it.
HTC Vive, Oculus Rift or PlayStation VR all are great, but they still have to connect with PCs with cables, then this can make us upset when limiting us moving around. The wires must fo away! At the moment we also have some tools that allow us to experience home VR without limited cables, but it seems that it is still not really enough for our use. Then we can come to standalone VR devices, maybe.
With VR, we want to have a fully immersive experience, not just only watch things inside the virtual world and just half-immerse into it. Then we still need some accessories to help us get that full immersion. Then, when we buy a VR headset, we should also know if that headset can connect with other devices, especially with wireless connection (such as Bluetooth).
The last but not least thing I want to mention here is the price of the VR headset.
The cheap thing won’t bring us the good things? This might be right for most of the cases, but it is not always right! At the moment, most of VR headsets have a quite high price, especially with home VR headset we have to invest a lot into it (such as a good PC). However, we still have a lot of great VR headsets with a very good price in the market. Don’t just think the most expensive can bring us the greatest experience!
Be aware of that we are just at the dawn time of VR technology, then there are more better things ahead.
There are many factors to make a great VR headsets, but in my opinion, the above are really what we should concern about when finding a VR headset. This is just my personal opinions, then I hope to hear more from you all!