Max. phone screen size
The largest diagonal of a smartphone compatible with the corresponding glasses (see "Intended use"). Note that this parameter can be specified both for universal models that do not have specialization for specific mobile phones, and for gadgets for specific devices (for more details, see "Compatible phone models"). The maximum diagonal is connected both with the features of the optics and with the physical dimensions of the "seat" for a mobile phone — a gadget that is too large simply does not fit there.
Note that even the smallest glasses for smartphones work quite correctly with devices with a diagonal of
5 – 5.5 ". So it makes sense to pay attention to this parameter if your device has a larger screen size. Nowadays, you can find glasses for gadgets
5.6 – 6 " and even
6" or more.
Field of view
The viewing angle provided by virtual reality glasses is the angular size of the space that falls into the user's field of view. Usually, the characteristics indicate the size of this space horizontally; however, if you need the most accurate information, this point needs to be specified separately.
The wider the viewing angle — the more the game space the user can see without turning his head, the more powerful the immersion effect and the less likely that the image will be subject to the "tunnel vision" effect. On the other hand, making the field of view too wide also does not make sense, given the characteristics of the human eye. In general, a
large viewing angle is considered to be an angle of 100° or more. On the other hand, there are models where this indicator is 30° or even less — these are, usually, specific devices (for example, drone piloting glasses and augmented reality glasses), where such characteristics are quite justified given the overall functionality.
Pupillary distance adjustment
The ability
to adjust the interpupillary distance of glasses — that is, the distance between the centers of two lenses. To do this, the lenses are mounted on movable mounts that allow them to be moved to the right / left. The meaning of this feature is that for normal viewing, the centers of the lenses must be opposite the user's pupils — and for different people, the distance between the pupils is also different. Accordingly, this setting will be useful anyway, but it is especially important for users of a large or petite physique, whose interpupillary distance is noticeably different from the average.
At the same time, there is a fairly significant number of glasses that do not have this function. They can be divided into three categories. The first is devices where the lack of adjustment for the interpupillary distance is compensated in one way or another (for example, by a special form of lenses that does not require adjustment). The second is models where this adjustment is not needed in principle (in particular, some augmented reality glasses). And the third — the simplest and cheapest solutions, where additional adjustments were abandoned to reduce the cost.
